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THE FREE MULTIMEDIA MAGAZINE THAT KEEPS YOU UPDATED ON WHAT IS HAPPENING IN SPACE

Bi-monthly magazine of scientific and technical information ✶ May-June 2021 IInnggeennuuiittyy’’ss ffiirrsstt fflliigghhtt

Magnetic fields at the edge of M87’s black hole imaged

Solar System’s most distant known object confirmed

• The earliest supermassive black hole and quasar in the Universe • New atmosphere forming on a rocky exoplanet • Shining a new light on dark energy • How to measure the relativistic jet of M87 • Six-exoplanet system challenges theories of how planets form

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Science in School aims to promote inspir- ing science teaching by encouraging communica- tion between teachers, scientists, and everyone else involved in European sci- ence education. Science in School is published by EIROforum, a collaboration between eight European intergovernmen- tal scientific research organisations, of which ESO is a member. The journal addresses science teaching both across Europe and across disciplines: highlighting the best in teaching and cutting-edge research. Read more about Science in School at: http://www.scienceinschool.org/ colophon EN_l'astrofilo 28/04/2021 16:53 Page 3

Ingenuity’s first flight BI-MONTHLY MAGAZINE OF SCIENTIFIC 4 AND TECHNICAL INFORMATION FREELY AVAILABLE THROUGH THE INTERNET Magnetic fields at the edge of M87’s black May-June 2021 12 hole imaged

The earliest supermassive black hole and quasar 16 in the Universe

New atmosphere forming on a rocky 20 exoplanet

A distant galaxy dies as astronomers 24 watch

English edition of the magazine lA’ STROFILO Shining a new light on dark 26 energy Editor in chief Michele Ferrara

Scientific advisor Prof. Enrico Maria Corsini How to measure the relativistic jet Publisher 30 of M87 Astro Publishing di Pirlo L. Via Bonomelli, 106 25049 Iseo - BS - ITALY email [email protected]

Internet Service Provider Most distant quasar with powerful radio Aruba S.p.A. jets discovered Via San Clemente, 53 36 24036 Ponte San Pietro - BG - ITALY

Copyright All material in this magazine is, unless otherwise stated, property of Astro Hubble pinpoints supernova Publishing di Pirlo L. or included with permission of its author. Reproduction 38 blast or retransmission of the materials, in whole or in part, in any manner, with- out the prior written consent of the copyright holder, is a violation of copy- right law. A single copy of the materi- Six-exoplanet system challenges theories als available through this course may be made, solely for personal, noncom- 42 of how planets form mercial use. Users may not distribute such copies to others, whether or not in electronic form, whether or not for a charge or other consideration, with- out prior written consent of the copy- Doubling the number of known right holder of the materials. The publisher makes available itself with 46 gravitational lenses having rights for possible not charac- terized iconographic sources.

Advertising - Administration Astro Publishing di Pirlo L. Solar System’s most distant known object Via Bonomelli, 106 25049 Iseo - BS - ITALY 50 confirmed email [email protected] magazine EN_Free Astronomy Magazine 28/04/2021 16:51 Page 4

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Ingenuity’s first flight

by Damian G. Allis NASA Solar System Ambassador

or 39 seconds this past April Flight by humans has a long history n the background, a frame of the th 19 , the Mars 2020 mission’s In- here on Earth. A cave painting on I first video of NASA’s Ingenuity Fgenuity helicopter performed Muna Island in Indonesia that dates Mars helicopter in flight. [NASA/JPL- the first demonstration of con- back to at least 9,000 B.C. depicts a Caltech/ASU/MSSS] trolled, powered flight on another kaghati, a kite whose design is still planet, including a 30-second hover in use today by the island commu- simple flight to controlled, powered three meters above where the Per- nities. Human flight also has a long, flight began on December 17, 1903 severance rover had deployed it on if sporadic, history, with recorded outside of Kitty Hawk, North Car- April 3rd. This first demonstration, human flight by attachment to a olina, with the 12-second flight of recorded by both Ingenuity and Per- kite dating back nearly two millen- the Wright Flyer by Orville Wright. severance, is the first step in dra- nia in China, and a first human lift With this first demonstration, and matically changing how we explore by hot air balloon recorded on Octo- additional flights by both Orville the red planet and beyond. ber 19th, 1783 in Paris. The leap from and Wilbur Wright, the force of

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his animation shows T each step of the Inge- nuity helicopter deploy- ing from the belly of NASA’s Perseverance Mars rover from March 26 to April 3, 2021. The final image shows the helicopter on the ground after the rover drove about 13 feet (4 meters) away. [NASA/JPL-Caltech]

he Ingenuity Mars T Helicopter’s carbon fiber blades can be seen in this video taken by the Mastcam- Z instrument aboard NASA’s Perseverance Mars rover on April 8, 2021, the 48th Martian day, or sol, of the mis- sion. The four blades are arranged into two 4-foot-long (1.2-meter- long) counter-rotating rotors that can spin at roughly 2,400 rpm. The video shows the blades performing a wiggle test before the actual spin-up to ensure they were working properly. [NASA/JPL-Caltech/ASU]

ASA’s Ingenuity helicopter does a slow spin test of its blades on N April 8, 2021, the 48th Martian day, or sol, of the mission. This image was captured by the Mastcam-Z on NASA’s Perseverance Mars rover. [NASA/JPL-Caltech/ASU]

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of supporting 30 minutes or more of with a sufficiently thick atmosphere. embers of NASA’s Ingenuity M helicopter team in the Space flight are both affordable and com- For Ingenuity, successful operation Flight Operations Facility at NASA’s monplace. The Ingenuity helicopter requires a delicate balance of weight, Jet Propulsion Laboratory prepare to extends drone capabilities on Earth battery size, internal heating, and receive the data downlink showing to Mars and to any other planets propeller design to work at a surface whether the helicopter completed its first flight on April 19, 2021. [NASA/JPL-Caltech]

wind – or the lack thereof – was no longer the factor determining where a vehicle could go. Fast-forward to 2021, and remote- controlled drones with built-in hi- def cameras and batteries capable

n this video captured by NASA’s I Perseverance rover, the agency's Ingenuity Mars Helicopter took the first powered, controlled flight on another planet on April 19, 2021. [NASA/JPL-Caltech/ASU/MSSS]

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ASA’s Ingenuity N Mars Helicopter achieves powered, con- trolled flight for the first time on another planet, hovering for several sec- onds before touching back down on April 19, 2021. The image was taken by the left Naviga- tion Camera, or Navcam, aboard the agency’s Per- severance Mars rover from a distance of 210 feet (64 meters). [NASA/JPL-Caltech]

atmospheric pressure less than 1% that on Earth and to survive temperatures as low as -130°F (-90°C). The Perseverance landing and the Mars 2020 Mis- sion were covered in de- tail in the March-April issue of this on Mars as has been implemented next set of driving coordinates, or by magazine. We mentioned then that here on Earth for centuries. the rovers having the ability to ana- an aerial vehicle on Mars was a solu- The planning of Martian rover jour- lyze and adjust headings and dis- tion to many issues that have com- neys has occurred either by humans tances near-autonomously. In both plicated our exploration of the red receiving data about the local envi- cases, this planning can only be in- planet, providing the same solution ronment and programming in the formed by as far as the onboard cam-

embers of NASA’s M Ingenuity helicopter team in the Space Flight Operations Facility at NASA’s Jet Propulsion Laboratory react to data showing that the helicop- ter completed its first flight on April 19, 2021. [NASA/JPL-Caltech]

eras could see. The combi- nation of slow speed, need for planning the path for- ward from a limited visual range, and the wealth of measurement and collec- tion being performed all were contributing reasons why the Opportunity rover, over 14 years of operation, only traveled 28 miles (45 km) from its landing site.

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ASA’s Ingenuity helicopter can be N seen here taking off, hovering and then landing on the Martian sur- face on April 19, 2021. The Mastcam-Z imager aboard NASA’s Perseverance Mars rover shot video of the heli- copter’s flight. The video is presented here in side-by-side formats that have both been enhanced to show a dust plume swirling during takeoff and again on landing. The view on the left uses motion filtering to show where dust was detected during liftoff and landing and the view on the right is enhanced with the motion filtering. Scientists use this image processing to detect dust devils as they pass by Mars rovers. An additional version of the video includes a timer that counts Opportunity journey and return to naissance Orbiter can be filled in by down until liftoff and then counts up the rover’s starting position in under drone, greatly improving both the until landing. A ghostly “cut-out” of three hours would be limited only internal path selection algorithms by the helicopter is visible in each side- by the onboard power to complete by-side format; that’s an artifact re- his altimeter chart shows data lated to the digital processing. the journey in a single flight. A con- siderable range of visual informa- T from the first flight of NASA’s [NASA/JPL-Caltech/ASU/MSSS/SSI] Ingenuity Mars Helicopter, which tion between the short-range views occurred on April 19, 2021. At a maximum speed of 10 m/s, In- of the rover cameras and the planet- [NASA/JPL-Caltech] genuity’s ability to image the entire scanning studies of the Mars Recon-

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ment on April 8th was successful, but a high-spin test on April 9th was cut short by a fault-detecting watchdog timer. With a software update sub- mitted on April 12th, a high-spin test on the 17th paved the way for the historic take-off on the 19th. The care and concern in testing prior to first flight are for obvious reasons – any unsuccessful take-off or rough land- ing on Mars would require either delicate reorienting movements by a rover ill-equipped for such fine- motor control, or human interven- tion in the form of the most expen- sive drone recovery in history. To paraphrase from another famous first, the first flight for Ingenuity was “one small flight for (a) helicop- ter, one giant flight for Martian air travel.” And, for the second time during the Mars 2020 mission, the

ASA’s Ingenuity Mars Helicopter N took this shot while hovering over the Martian surface on April 19, 2021, during the first instance of powered, controlled flight on an- other planet. It used its navigation camera, which autonomously tracks the ground during flight. On the side, an enlargement that highlights details of the Martian soil under- neath the shade. [NASA/JPL-Caltech]

autonomous rovers and the ability of those rovers to do much more meaningful discovery and analysis much more efficiently. The next few rover missions them- selves may benefit greatly from as- sociated drones beyond just better imagery and path planning. Drones provide a means to quickly return- ing sample collections to a common location for analysis or eventual re- turn to Earth for study. Designs ca- cliffs, the walls of any ancient im- contingency speech written for mis- pable of supporting more weight pact craters, or water-carved cer- sion failure was ripped up during can also host spectroscopic equip- vices that might hide the remnants the live video feed. This time, it was ment to pre-study areas prior to of ancient ecosystems. JPL Project Manager MiMi Aung, rover arrival. Drones also provide Like so many flights, this first demon- exclaiming “We can now say that access to places rovers simply cannot stration was not without some delay. human beings have flown a rotor- yet go – sedimentary layers in tall An initial slow-spin test after deploy- craft on another planet!” !

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The NortheK Rapido 450 is designed to be disassembled into essential parts for transport in a small car. Each component is equipped with its own case, facilitating transport and assembly. The main element weighs 27 kg. Incorporated mechanical devices and the precise execution of each component allows for the collimation of the optics with extreme ease, maintaining collimation throughout an observation session while eliminating twisting and bending, regardless of the weight of the accessories used. The very thin primary optic allows for rapid acclimatization and ensures thermal stability throughout the night. Two bars equipped with sliding weights allow for the perfect balance of the telescope and accessories. On demand, it is also possible to modify the support to mount the telescope on an equatorial platform. This instrument is composed of aluminum, carbon and steel, each perfectly selected according to strict mechanical standards. It is undoubtedly the best altazimuth Newtonian on the market. magazine EN_Free Astronomy Magazine 28/04/2021 16:51 Page 11

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images by Massimo Vesnaver magazine EN_Free Astronomy Magazine 28/04/2021 16:51 Page 12

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Magnetic fields at the edge of M87’s black hole imaged

by ESO - Bárbara Ferreira

he Event Horizon Telescope the first time astronomers have been his image shows the polarised (EHT) collaboration, who pro- able to measure polarisation, a sig- view of the black hole in M87. duced the first ever image of a nature of magnetic fields, this close T T The lines mark the orientation of po- black hole, revealed a new view of to the edge of a black hole. The ob- larisation, which is related to the the massive object at the centre of servations are key to explaining how magnetic field around the shadow of the Messier 87 (M87) galaxy: how the M87 galaxy, located 55 million the black hole. [EHT Collaboration] it looks in polarised light. This is light-years away, is able to launch

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energetic jets from its core. “We are essier 87 (M87) is an enormous now seeing the next crucial piece of M elliptical galaxy located about evidence to understand how mag- 55 million light years from Earth, vis- netic fields behave around black ible in the constellation Virgo. At holes, and how activity in this very double the mass of our own galaxy, compact region of space can drive the Milky Way, and containing as powerful jets that extend far be- many as ten times more stars, it is yond the galaxy,” says Monika Mo ś? amongst the largest galaxies in the cibrodzka, Coordinator of the EHT local universe. [ESO] Polarimetry Working Group and As- sistant Professor at Radboud Univer- cant fraction of the light around the sity in the Netherlands. M87 black hole is polarised. On 10 April 2019, scientists released “This work is a major milestone: the the first ever image of a black hole, polarisation of light carries informa- revealing a bright ring-like structure tion that allows us to better under- with a dark central region — the stand the physics behind the image black hole’s shadow. we saw in April 2019, which was Since then, the EHT collaboration not possible before,” explains Iván has delved deeper into the data on Martí-Vidal, also Coordinator of the the supermassive object at the heart EHT Polarimetry Working Group and of the M87 galaxy collected in 2017. GenT Distinguished Researcher at They have discovered that a signifi- the University of Valencia, Spain.

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his composite image shows three views of the central region of the Messier 87 (M87) galaxy in polarised light. The galaxy T has a supermassive black hole at its centre and is famous for its jets, that extend far beyond the galaxy. One of the po- larised-light images, obtained with the Chile-based Atacama Large Millimeter/submillimeter Array (ALMA), in which ESO is a partner, shows part of the jet in polarised light. This image captures the part of the jet, with a size of 6000 light years, closer to the centre of the galaxy. The other polarised light images zoom in closer to the supermassive black hole: the middle view cov- ers a region about one light year in size and was obtained with the National Radio Astronomy Observatory’s Very Long Base- line Array (VLBA) in the US. The most zoomed-in view was obtained by linking eight telescopes around the world to create a virtual Earth-sized telescope, the Event Horizon Telescope or EHT. This allows astronomers to see very close to the supermas- sive black hole, into the region where the jets are launched. The lines mark the orientation of polarisation, which is related to the magnetic field in the regions imaged.The ALMA data provides a description of the magnetic field structure along the jet. Therefore the combined information from the EHT and ALMA allows astronomers to investigate the role of magnetic fields from the vicinity of the event horizon (as probed with the EHT on light-day scales) to far beyond the M87 galaxy along its powerful jets (as probed with ALMA on scales of thousand of light-years). The values in GHz refer to the frequencies of light at which the different observations were made. The horizontal lines show the scale (in light years) of each of the individual im- ages. [EHT Collaboration; ALMA (ESO/NAOJ/NRAO), Goddi et al.; VLBA (NRAO), Kravchenko et al.; J. C. Algaba, I. Martí-Vidal]

He adds that “unveiling this new po- like the lenses of polarised sun- glare from bright surfaces, as- larised-light image required years of glasses, or when it is emitted in hot tronomers can sharpen their view of work due to the complex techniques regions of space where magnetic the region around the black hole by involved in obtaining and analysing fields are present. In the same way looking at how the light originating the data.” Light becomes polarised that polarised sunglasses help us see from it is polarised. Specifically, po- when it goes through certain filters, better by reducing reflections and larisation allows astronomers to map

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the magnetic field lines search,” says Ciska Kem- present at the inner per, European ALMA edge of the black hole. Programme Scientist at “The newly published ESO. “With its 66 anten- polarised images are key nas, ALMA dominates to understanding how the overall signal collec- the magnetic field al- tion in polarised light, lows the black hole to while APEX has been es- 'eat' matter and launch sential for the calibra- powerful jets,” says EHT tion of the image.” collaboration member “ALMA data were also Andrew Chael, a NASA crucial to calibrate, im- Hubble Fellow at the age and interpret the Princeton Center for EHT observations, pro- Theoretical Science and viding tight constraints the Princeton Gravity on the theoretical mod- Initiative in the US. his video summarises the discovery made by the Event Horizon els that explain how The bright jets of en- T Telescope (EHT) collaboration. [ESO] matter behaves near the ergy and matter that black hole event hori- emerge from M87’s core and extend what they are seeing at the event zon,” adds Ciriaco Goddi, a scientist at least 5000 light-years from its horizon. “The observations suggest at Radboud University and Leiden centre are one of the galaxy’s most that the magnetic fields at the black Observatory, the Netherlands, who mysterious and energetic features. hole’s edge are strong enough to led an accompanying study that re- Most matter lying close to the edge push back on the hot gas and help lied only on ALMA observations. of a black hole falls in. However, it resist gravity’s pull. Only the gas The EHT setup allowed the team some of the surrounding particles that slips through the field can spi- to directly observe the black hole escape moments before capture ral inwards to the event horizon,” shadow and the ring of light and are blown far out into space in explains Jason Dexter, Assistant Pro- around it, with the new polarised- the form of jets. fessor at the University of Colorado light image clearly showing that the Astronomers have relied on differ- Boulder, US, and Coordinator of the ring is magnetised. ent models of how matter behaves EHT Theory Working Group. The results have been published in near the black hole to better under- To observe the heart of the M87 two separate papers in The Astro- stand this process. But they still galaxy, the collaboration linked physical Journal Letters by the EHT don’t know exactly how jets larger eight telescopes around the world collaboration. The research involved than the galaxy are launched from — including the northern Chile- over 300 researchers from multiple its central region, which is compara- based Atacama Large Millimeter/ organisations and universities world- ble in size to the Solar System, nor submillimeter Array (ALMA) and wide. how exactly matter falls into the the Atacama Pathfinder EXperiment “The EHT is making rapid advance- black hole. With the new EHT image (APEX), in which the European ments, with technological upgrades of the black hole and its shadow in Southern Observatory (ESO) is a being done to the network and polarised light, astronomers man- partner — to create a virtual Earth- new observatories being added. We aged for the first time to look into sized telescope, the EHT. The im- expect future EHT observations to the region just outside the black pressive resolution obtained with reveal more accurately the mag- hole where this interplay between the EHT is equivalent to that needed netic field structure around the matter flowing in and being ejected to measure the length of a credit black hole and to tell us more about out is happening. card on the surface of the Moon. the physics of the hot gas in this re- The observations provide new infor- “With ALMA and APEX, which gion,” concludes EHT collaboration mation about the structure of the through their southern location en- member Jongho Park, an East Asian magnetic fields just outside the hance the image quality by adding Core Observatories Association Fel- black hole. The team found that geographical spread to the EHT net- low at the Academia Sinica Institute only theoretical models featuring work, European scientists were able of Astronomy and Astrophysics in strongly magnetised gas can explain to play a central role in the re- Taipei. !

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The earliest supermassive black hole and quasar in the Universe

by NOIRLab - Amanda Kocz

uasars, which are powered by the feeding frenzies of colossal supermassive black holes, are the Qmost energetic objects in the Universe. They occur when gas in the superheated ac- cretion disk around a supermassive black hole is inexorably drawn in- wards, shedding energy across the electromagnetic spec- trum. The amount of electromagnetic r a d i a t i o n

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n artist’s impression of quasar J0313-1806 showing the supermassive black A hole and the extremely high velocity wind. The quasar, seen just 670 million years after the Big Bang, is 1000 times more luminous than the Milky Way, and is powered by the earliest known supermassive black hole, which weighs in at more than 1.6 billion times the mass of the Sun. [NOIRLab/NSF/AURA/J. da Silva]

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emitted by quasars is enormous, with the most massive examples eas- ily outshining entire galaxies. An in- ternational team of astronomers has announced the discovery of J0313- 1806, the most distant quasar known to date. “The most distant quasars are crucial for understanding how the earliest black holes formed and for understanding cosmic reioniza- tion — the last major phase transi- tion of our Universe,” said Xiaohui Fan, study co-author and Regents Professor of Astronomy at the Uni- versity of Arizona. J0313-1806 is seen more than 13 bil- lion years ago. As the most distant his is CosmoView Episode 17 for press release noirlab2102: The earliest su- quasar known, it is also the earliest, T permassive black hole and quasar in the Universe. [Images and Videos: being fully formed only about 670 NOIRLab/NSF/AURA/J. da Silva, ESO/M.Kornmesser, CTIO/D. Munizaga, Interna- million years after the Big Bang. The tional Gemini Observatory/Kwon O Chul. Music: Stellardrone - Comet Halley] new quasar is more than ten trillion times as luminous as our Sun — the DESI Legacy Imaging Surveys, large enough to impact the star for- meaning that it pours out one thou- which are served to the astronomi- mation in the entire quasar host sand times more energy than the cal community via the Astro Data galaxy,” said Jinyi Yang, Peter A. entire Milky Way Galaxy. The source Lab at NOIRLab’s Community Sci- Strittmatter postdoctoral fellow of of this quasar’s power is a supermas- ence and Data Center (CSDC), Steward Observatory at the Univer- sive black hole 1.6 billion times as helped to first identify J0313-1806, sity of Arizona. This is the earliest massive as the Sun — the earliest while Gemini South observations known example of a quasar sculpt- black hole currently known to exist were used to confirm its identity as ing the growth of its host galaxy, in the Universe. a quasar. High-quality spectra from making J0313-1806 a promising tar- The presence of such a massive black two Maunakea observatories in get for future observations. hole so early in the Universe’s history Hawai‘i — Gemini North and W. M. The galaxy hosting J0313-1806 is un- challenges theories of black hole Keck Observatory — were used to dergoing a spurt of star formation, formation as astronomers need to measure the mass of the central su- producing new stars 200 times faster explain how it came into existence permassive black hole. than the Milky Way. The combina- when it barely had the time to do “The most distant quasars and earli- tion of this intense star formation, so. Feige Wang, NASA Hubble fel- est black holes are important mark- the luminous quasar, and the high- low at the University of Arizona and ers in the history of the Universe,” velocity outflow make J0313-1806 lead author of the research paper, said Program Director Martin Still of and its host galaxy a promising nat- explains: “Black holes created by the the National Science Foundation. ural laboratory for understanding very first massive stars could not “The researchers combined several the growth of supermassive black have grown this large in only a few of NSF’s NOIRLab facilities to make holes and their host galaxies in the hundred million years.” this discovery.” early Universe. The observations that led to this dis- As well as weighing the monster “This would be a great target to in- covery were made using a variety of black hole, the Gemini North and vestigate the formation of the ear- telescopes, including three National Keck Observatory observations un- liest supermassive black holes,” con- Science Foundation NOIRLab facili- covered an extremely fast outflow cluded Feige Wang. “We also hope ties — the Víctor M. Blanco 4-meter emanating from the quasar in the to learn more about the effect of Telescope at Cerro Tololo Inter- form of a high-velocity wind, which quasar outflows on their host galaxy American Observatory, Gemini South, is traveling at 20% of the speed of — as well as to learn how the most and Gemini North. Data from the light. “The energy released by such massive galaxies formed in the early Blanco Telescope, taken as part of an extreme high-velocity outflow is Universe.” !

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New atmosphere forming on a rocky exoplanet

by NASA/ESA - Bethany Downer

or the first time, scientists using star. In a short period of time, it was the NASA/ESA Hubble Space reduced to a bare core about the FTelescope have found evidence size of Earth. of volcanic activity reforming the at- To the surprise of astronomers, new mosphere on a rocky planet around observations from Hubble have un- a distant star. The planet, GJ 1132 b, covered a secondary atmosphere has a similar density, size, and age that has replaced the planet’s first to those of Earth. atmosphere. It is rich in hydrogen, The planet GJ 1132 b appears to hydrogen cyanide, methane and have begun life as a gaseous world ammonia, and also has a hydrocar- with a thick blanket of atmosphere. bon haze. Astronomers theorise that Starting out at several times the ra- hydrogen from the original atmos- dius of Earth, this so-called “sub- phere was absorbed into the Neptune” quickly lost its primordial planet’s molten magma mantle and hydrogen and helium atmosphere, is now being slowly released by vol- which was stripped away by the in- canism to form a new atmosphere. tense radiation from its hot, young This second atmosphere, which con-

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his image is an artist’s impression T of the exoplanet GJ 1132 b. [NASA, ESA, and R. Hurt (IPAC/Caltech)]

tinues to leak away into space, is they lost their atmospheres,” said continually being replenished from team member Raissa Estrela of the the reservoir of hydrogen in the Jet Propulsion Laboratory at the Cal- mantle’s magma. ifornia Institute of Technology in “This second atmosphere comes Pasadena, California, USA. “But we from the surface and interior of the looked at existing observations of planet, and so it is a window onto this planet with Hubble and realised the geology of another world,” ex- that there is an atmosphere there.” plained team member Paul Rimmer “How many terrestrial planets don’t of the University of Cambridge, UK. begin as terrestrials? Some may start “A lot more work needs to be done as sub-Neptunes, and they become to properly look through it, but the terrestrials through a mechanism discovery of this window is of great whereby light evaporates the pri- importance.” mordial atmosphere. This process “We first thought that these highly works early in a planet’s life, when radiated planets would be pretty the star is hotter,” said team leader boring because we believed that Mark Swain of the Jet Propulsion

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tance from our yellow dwarf Sun. GJ the same face to its star at all times ictured here is the region around P the host star of the exoplanet GJ 1132 b is so close to its host red — just as our moon keeps one hemi- 1132 b. [ESA/Hubble, Digitized Sky dwarf star that it completes an orbit sphere permanently facing Earth. Survey 2. Ack: Davide De Martin] the star once every day and a half. “The question is, what is keeping This extremely close proximity keeps the mantle hot enough to remain Laboratory. “Then the star cools GJ 1132 b tidally locked, showing liquid and power volcanism?” asked down and the planet’s just sitting there. So you’ve got this mechanism that can cook off the atmosphere in the first 100 million years, and then things settle down. And if you can regenerate the atmosphere, maybe you can keep it.” In some ways, GJ 1132 b has various parallels to Earth, but in some ways it is also very different. Both have similar densities, similar sizes, and similar ages, being about 4.5 billion years old. Both started with a hydro- gen-dominated atmosphere, and both were hot before they cooled down. The team’s work even sug- gests that GJ 1132 b and Earth have similar atmospheric pressure at the surface. n this Space Sparks episode, ESA/Hubble summarises an exciting new discovery However, the planets’ formation his- Ifrom the NASA/ESA Hubble Space Telescope. [Directed by: Bethany Downer tories are profoundly different. and Nico Bartmann. Editing: Nico Bartmann. Web and technical support: Enciso Systems. Written by: Bethany Downer. Music: STAN DART – Organic Life (Music Earth is not believed to be the sur- written and performed by STAN DART). Footage and photos: ESA/Hubble & viving core of a sub-Neptune. And NASA, R. Hurt (IPAC/Caltech)] Earth orbits at a comfortable dis-

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his plot shows the spectrum of the atmosphere of an Earth sized rocky exoplanet, GJ 1132 b, which is overlaid on an artist’s T impression of the planet. The orange line represents the model spectrum. In comparison, the observed spectrum is shown as blue dots representing averaged data points, along with their error bars. This analysis is consistent with GJ 1132 b being predominantly a hydrogen atmosphere with a mix of methane and hydrogen cyanide. The planet also has aerosols which cause scattering of light. This is the first time a so-called “secondary atmosphere,” which was replenished after the planet lost its primordial atmosphere, has been detected on a world outside of our solar system. [NASA, ESA, and P. Jeffries (STScI)]

Swain. “This system is special be- as a result of a tidal tug-of-war be- trum of the atmosphere, but rather cause it has the opportunity for tween Jupiter and the neighbouring the spectrum of the surface,” ex- quite a lot of tidal heating.” Jovian moons. plained Swain. “And if there are The phenomenon of tidal heating The team believes the crust of GJ magma pools or volcanism going on, occurs through friction, when en- 1132 b is extremely thin, perhaps those areas will be hotter. That will ergy from a planet’s orbit and rota- only hundreds of feet thick. That’s generate more emission, and so tion is dispersed as heat inside the much too feeble to support any- they’ll potentially be looking at the planet. GJ 1132 b is in an elliptical thing resembling volcanic moun- actual geological activity — which is orbit, and the tidal forces acting on tains. Its flat terrain may also be exciting!” it are strongest when it is closest to cracked like an eggshell by tidal flex- “This result is significant because it or farthest from its host star. ing. Hydrogen and other gases could gives exoplanet scientists a way to At least one other planet in the host be released through such cracks. figure out something about a star’s system also exerts a gravita- “This atmosphere, if it’s thin — planet’s geology from its atmos- tional pull on the planet. The conse- meaning if it has a surface pressure phere,” added Rimmer. “It is also im- quences are that the planet is similar to Earth — probably means portant for understanding where squeezed or stretched by this gravi- you can see right down to the the rocky planets in our own Solar tational “pumping.” That tidal heat- ground at infrared wavelengths. System — Mercury, Venus, Earth and ing keeps the mantle liquid for a That means that if astronomers use Mars, fit into the bigger picture of long time. A nearby example in our the James Webb Space Telescope to comparative planetology, in terms own Solar System is the Jovian moon, observe this planet, there’s a possi- of the availability of hydrogen ver- Io, which has continuous volcanism bility that they will see not the spec- sus oxygen in the atmosphere.” !

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A distant galaxy dies as astronomers watch

by ESO - Bárbara Ferreira

alaxies begin to “die” when ID2299. Because the galaxy is also they stop forming stars, but forming stars very rapidly, hundreds Guntil now astronomers had of times faster than our Milky Way, never clearly glimpsed the start of the remaining gas will be quickly this process in a far-away galaxy. consumed, shutting down ID2299 in Using the Atacama Large Millime- just a few tens of million years. ter/submillimeter Array (ALMA), The event responsible for the spec- in which the European Southern tacular gas loss, the team believes, is Observatory (ESO) is a partner, as- a collision between two galaxies, tronomers have seen a galaxy eject- which eventually merged to form ing nearly half of its star-forming ID2299. gas. “This is the first time we have The elusive clue that pointed the sci- observed a typical massive star-form- entists towards this scenario was the ing galaxy in the distant Universe association of the ejected gas with a about to ‘die’ because of a massive “tidal tail”. Tidal tails are elongated cold gas ejection,” says Annagrazia streams of stars and gas extending Puglisi, lead researcher on the new into interstellar space that result study, from the Durham University, when two galaxies merge, and they UK, and the Saclay Nuclear Research are usually too faint to see in distant Centre (CEA-Saclay), France. galaxies. However, the team man- The galaxy, ID2299, is distant aged to observe the relatively bright enough that its light takes some 9 feature just as it was launching into billion years to reach us; we see it space, and were able to identify it as when the Universe was just 4.5 bil- a tidal tail. Most astronomers be- lion years old. lieve that winds caused by star The gas ejection is happening at a formation and the activity of black rate equivalent to 10,000 Suns per holes at the centres of massive gal- year, and is removing an astonishing axies are responsible for launching 46% of the total cold gas from star-forming material into space,

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his artist’s impression of ID2299 shows the galaxy, the product of a galactic T collision, and some of its gas being ejected by a “tidal tail” as a result of the merger. New observations made with ALMA, in which ESO is a partner, have captured the earliest stages of this ejection, before the gas reached the very large scales depicted in this artist’s impression. [ESO/M. Kornmesser]

thus ending galaxies’ ability to make with ALMA, designed to study the new stars. However, the new study properties of cold gas in more than published in Nature Astronomy sug- 100 far-away galaxies. ID2299 had gests that galactic mergers can also been observed by ALMA for only a be responsible for ejecting star- few minutes, but the powerful ob- forming fuel into space. servatory, located in northern Chile, “Our study suggests that gas ejec- allowed the team to collect enough tions can be produced by mergers data to detect the galaxy and its and that winds and tidal tails can ap- ejection tail. “ALMA has shed new pear very similar,” says study co-au- light on the mechanisms that can thor Emanuele Daddi of CEA-Saclay. halt the formation of stars in distant Because of this, some of the teams galaxies. Witnessing such a massive that previously identified winds disruption event adds an important from distant galaxies could in fact piece to the complex puzzle of have been observing tidal tails eject- galaxy evolution,” says Chiara Cir- ing gas from them. “This might lead costa, a researcher at the University us to revise our understanding of College London, UK, who also con- how galaxies ‘die’,” Daddi adds. tributed to the research. Puglisi agrees about the significance In the future, the team could use of the team’s finding, saying: “I was ALMA to make higher-resolution thrilled to discover such an excep- and deeper observations of this tional galaxy! I was eager to learn galaxy, enabling them to better un- more about this weird object be- derstand the dynamics of the cause I was convinced that there was ejected gas. Observations with the some important lesson to be learned future ESO’s Extremely Large Tele- about how distant galaxies evolve.” scope could allow the team to ex- This surprising discovery was made plore the connections between the by chance, while the team were in- stars and gas in ID2299, shedding specting a survey of galaxies made new light on how galaxies evolve. !

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Shining a new light on dark energy

by NOIRLab - Amanda Kocz

R2 is the second release of im- data release (DR1), and also im- ages and object catalogs from proves on it by refining calibration Dthe Dark Energy Survey (DES). techniques, which, with the deeper It is the culmination of over half a combined images from DR2, leads decade of astronomical data collec- to improved estimates of the tion and analysis, with the ultimate amount and distribution of matter goal of understanding the acceler- in the Universe. It is one of the ating expansion rate of the Universe largest astronomical catalogs re- and the phenomenon of dark en- leased to date. ergy that is thought to be responsi- Astronomical researchers around ble for the expansion. The Dark the world can access these unprece- Energy Survey is a global collabora- dented data and mine them to tion that includes the Department make new discoveries about the of Energy’s (DOE) Fermi National Universe, complementary to the Accelerator Laboratory (Fermilab), studies being carried out by the the National Center for Supercom- Dark Energy Survey collaboration. puting Applications (NCSA), and One early result relates to the con- NSF’s NOIRLab. struction of a catalog of RR Lyrae Including a catalog of nearly 700 pulsating stars, which tell scientists million astronomical objects, DR2 about the region of space beyond builds on the 400 million objects the edge of our Milky Way. In this cataloged with the Survey’s previous area nearly devoid of stars, the mo-

his image shows unusual structures around NGC 474 characterized as tidal T tails and shell-like structures made up of hundreds of millions of stars. These features are due to recent mergers (within the last billion years) or close interac- tions with smaller infalling dwarf galaxies. This image is an excerpt from the Dark Energy Survey, which has released a massive, public collection of astro- nomical data and calibrated images from six years of work. [DES/DOE/Fermilab/ NCSA & CTIO/NOIRLab/NSF/AURA - Ack: Image processing: DES, Jen Miller (Gem- ini Observatory/NSF's NOIRLab), Travis Rector (University of Alaska Anchorage), Mahdi Zamani & Davide de Martin] magazine EN_Free Astronomy Magazine 28/04/2021 16:51 Page 27 magazine EN_Free Astronomy Magazine 28/04/2021 16:51 Page 28

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The detailed precision cos- mology constraints based on the full six-year DES dataset will come out over the next two years. DES was conceived to map hundreds of millions of galaxies and to chart the size of the expanding Uni- verse as it accelerates under the influence of dark en- ergy. DES has produced the largest and most accurate dark matter map from gal- axy weak lensing to date. Covering 5,000 square de- grees of the southern sky, the survey data enable many other investigations in addition to those targeting dark energy, covering a vast range of cosmic distances — from discovering new nearby Solar System objects to investigating the nature of the first star-forming gal- axies in the early Universe. “This is a momentous mile- stone. For six years, the Dark Energy Survey collaboration took pictures of distant ce- lestial objects in the night sky. Now, after carefully checking the quality and calibration of the images he irregular dwarf galaxy IC 1613 contains some 100 million stars and is a member of captured by the Dark En- T our Local Group of galaxies, which also includes our Milky Way, the Andromeda spiral galaxy, and the Magellanic Clouds. Also this image is an excerpt from the Dark Energy ergy Camera, we are releas- Survey. [DES/DOE/Fermilab/NCSA & CTIO/NOIRLab/NSF/AURA - Ack: Image processing: ing this second batch of DES, Jen Miller (Gemini Observatory/NSF’s NOIRLab), Travis Rector (University of Alaska data to the public,” said DES Anchorage), Mahdi Zamani & Davide de Martin] Director Rich Kron of Fermi- lab and the University of tion of the RR Lyrae stars hints at the of other techniques, infer the value Chicago. “We invite professional presence of an enormous “halo” of of the Hubble constant, a key cos- and amateur scientists alike to dig invisible dark matter, which may mological parameter. into what we consider a rich mine of provide clues to how our galaxy was Combining their data with other gems waiting to be discovered.” assembled over the last 12 billion surveys, DES scientists have also The primary tool used to collect years. In another result, DES scien- been able to generate a detailed these images, the Dark Energy Cam- tists used the extensive DR2 galaxy map of the Milky Way’s dwarf satel- era (DECam), fabricated by DOE, is catalog, along with data from the lites, giving researchers insight into mounted on the National Science LIGO gravitational wave experi- how our own galaxy was assembled Foundation-funded Víctor M. Blanco ment, to estimate the location of a and how it compares with cosmolo- 4-meter Telescope, part of the Cerro black hole merger and, independent gists’ predictions. Tololo Inter-American Observatory

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he Dark Energy Camera (DECam) T focal plane consists of a science array of sixty-two 2048 x 4096 CCDs. Additionally, there are four 2048 x 2048 guider CCDs and eight 2048 x 2048 focus and alignment CCDs. The quantum efficiency of these LBNL- designed CCDs with their anti-re- flective coating is red optimized to be more than 90% at 900 nm and more than 60% over the range of 400-1000 nm. The Dark Energy Sur- vey CCDs were fabricated by Dalsa with further processing done by Lawrence Berkeley National Labora- tory (Berkeley Lab). They were then packaged and tested by the Depart- ment of Energy's (DOE) Fermilab. DECam was fabricated by the DOE. [DES/DOE/LBNL/CTIO/NOIRLab/NSF/A URA/R. Hahn]

(CTIO) in the Chilean Andes, a Pro- gram of NSF’s NOIRLab. Each week from 2013 to 2019, DECam collected thousands of images of the southern sky, unlocking a trove of potential cosmological insights. Once captured, these images (and the large amount of data surround- ing them) were transferred to NCSA for processing via the DES Data Management (DESDM) project. Using the Blue Waters supercom- puter at NCSA, the Illinois Campus Cluster, and compu- tems, user services, and develop- tational systems at ment initiatives to connect and sup- Fermilab, NCSA pre- port the scientific missions of NOIR- pares calibrated data Lab’s telescopes, including the Blan- products for research co Telescope at CTIO. and public consump- “Because astronomical datasets to- tion. It took approxi- day are so vast, the cost of handling mately four months them is prohibitive for individual re- to process one year’s searchers or most organizations,” worth of data into a said Robert Nikutta, Project Scientist searchable, usable for Astro Data Lab at CSDC. “CSDC catalog. The DES DR2 provides open access to big astro- is hosted at the Com- nomical datasets like DES DR2, and he Dark Energy Camera (DECam) focal plane com- munity Science and the necessary tools to explore and T pared with the size of a person. DECam was fabri- Data Center (CSDC), exploit them — then all it takes is cated by the Department of Energy (DOE). [DES/DOE/ a Program of NSF’s someone from the community with LBNL/CTIO/NOIRLab/NSF/AURA/R. Hahn] NOIRLab. CSDC pro- a clever idea to discover new and vides software sys- exciting science.” !

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How to measure the relativistic jet of M87

by Aniceto Porcel & Miguel Sánchez revised by Damian G. Allis NASA Solar System Ambassador

his work describes spatial measurements made of the plasma jet emanating from the T nucleus of the galaxy M87 and based on ob- servations performed at the La Laguna Astronomical Observatory (OLA, Granada, Spain). With this work, apart from our interest in the study itself, we want to demonstrate that it is possible to undertake “ap- parently inaccessible” astronomical investigations and calculations with the aid of typical amateur in- struments, with both telescope diameters and focal lengths far below those we find in professional ob- servatories, but which nevertheless give good re- sults when we are able to exploit the potential of our team for collecting and processing data. The calculations we carried out to obtain the dimen- sions of the M87 jet are not complex; the main dif- ficulty in this study was the isolation of the jet from the great brightness of the galaxy’s core. Given the resolving power of the instruments used, there is a higher degree of uncertainty in the values we have obtained compared to result one might obtain by using higher-resolution equipment and more elab- orate calculation techniques. However, as we shall see, our results are consistent with those considered to be the “established values” from observations with professional telescopes, including the Hubble Space Telescope (HST).

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In March 2019 at the La Laguna As- mage of the M87 field taken from tronomical Observatory, we took a I OLA on 9 March 2019. [M. Sánchez sequence of images of M87 to (SAG), A. Porcel (SAG/OLA)] record the jet of matter that em- anates outwards from its center. This later, the media announced with plasma jet, or relativistic jet, was first considerable fanfare that the Event identified in 1918 by astronomer Horizon Telescope (EHT) team had Heber Curtis (Lick Observatory), but captured the first image of a black it was many years later before the hole. Quite fortuitously, the imaged details of the expulsion of matter black hole was the one at the center were finally revealed. of M87, and the jet we were trying These galactic jet-shaped structures to observe in our images has long are not unusual. The idea of captur- been the clearest evidence of what ing this one from OLA started as a that galaxy hosts at its core. The co- challenge when we saw that our incidence was exciting: while we first images showed a small promi- were trying to capture and measure nence indicating its presence, and the jet of highly-collimated matter n the background, the black hole- we wondered if it was possible to emerging from the core of M87, an I powered jet of electrons and sub- improve on that result. international team of astronomers atomic particles that streams from The first images recorded on March was concretizing the first visual evi- the center of M87. [NASA and The Hubble Heritage Team (STScI/AURA)] 9, 2019 were archived for further dence of the very black hole that processing. On April 10, just a month caused it. In truth, it has long been

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thought that the M87 jet was the result of a black hole, even though it nor any other black hole had been seen directly. For decades, black holes had only been a theory supported by indi- rect observational evidence, such as through their gravi- tational influence and by the jets of matter ejected at very high speeds from galac- tic nuclei. It is not easy to record this structure using the equipment available at OLA, not so much for the weakness and thinness of the jet, but mainly due to the great brightness of the M87 core, which saturates the pixels imaging the cen- ter of the galaxy, hiding the fine details in that region. In the images and in the first treatments, the plasma jet appears only as a small swelling or spike that only indicated its faint presence or, perhaps, showed it to be just a bit more prominent. The integration times had to be calculated carefully. Likewise, the choice of fil- ters to be used and their characteristics were impor- tant − we were trying to he jet of M87. Forced processing to isolate the plasma jet from the galaxy core makes record true color using the T the field stars appear with strange edges and halos. 10” f/3.9 Newtonian telescope, SBIG LRGB color palette. Subse- ST-8300M CCD camera, 8.3 megapixel KAF-8300 sensor, 5.4x5.4 (3326x2504 pixels), Ger- µ quently, we verified that the man equatorial mount EQ-8. [M. Sánchez (SAG), A. Porcel (SAG/OLA)] jet, being bluish, would have required an increase in the in- The images were acquired with the minance (L) in the red (R+L) channel tegrations of the blue filter (B), but help of the software programs and independent green (G) and blue ignorance of this made us assign Maxim DL, Astrotortilla, EQMOD (B) channels. The color (RGB) mon- identical exposure times to each fil- and Cartes du Ciel. Each of the pro- tage was done with Photoshop, ter. We also did exposures in H , duced FITS (Flexible Image Trans- where it was reworked to recali- α knowing (or almost knowing) that port System) files was initially brate color, brightness and contrast. they would not provide any extra processed with Avis FITS Viewer The IRIS program was used for the information. As they would likely (AvisFV) to reduce the brightness of spatial measurements of the jet. worsen our signal-to-noise ratio, the galaxy’s core until the plasma The final image of the M87 field is which became evident in the pro- jet was exposed. an LRGB stacking in the following cessing, we ultimately discarded the Image stacking was performed with proportions: L 3×300", R 3×300", G H data. DeepSkyStacker (DSS), including lu- 3×300", B 3×300"; 12 shots of 300 α

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seconds; total exposure of 3,600 sec- Now we just had to measure how we get the value: onds (1 hour). many pixels the jet occupied in our After enjoying the jet as seen in image, from the center of the gal- 855.6 ± 285 light-years these images, we asked ourselves: axy to the edge of the jet, using the (262.3 ± 87.4 pcs) “What if we used them to measure “Slice” tool of the IRIS program. wide. the size of the jet? Would we get This gave us 16 ± 1 pixels. The accepted value for the jet is measurements similar to the ac- cepted ones?” Taking as known the distance to M87 (53 million light-years) and by being able to calculate the apparent size of the jet in arcseconds from our exposures, we calculated the jet size by applying basic trigonometry. We know that, using the tangent formula, we can relate the angle and the two catheti, which is just what we needed in our case:

By multiplying our R by 16, we get about 5,000 light-years, or about 20 about 17.8 arcseconds, which we arcseconds, placing our calculation Because the angle is so small, the then substitute in the formula dis- within reasonable margins. tangent can be approximated as the cussed above to get d: angle itself: Conclusions Jets are structures that exhibit very . interesting properties and exist in amazing conditions due to their ex- And by transforming the angle from treme nature and properties. radians to arcseconds we get: which is: Knowing more about them yields a greater understanding about quasars, radio galaxies, active galax- arcseconds 4,542 ± 285 light-years (1,392.6 ± 87.4 pcs) ies and black holes. In the case of of length. the M87 jet, whose spatial dimen- With D known − 5×1023 m (53 mil- sions we have studied, we believe lion light-years converted into me- we have obtained results compara- ters) − we simply had to calculate Even taking 3 ± 1 pixels for the width ble with official data using far more how many arcseconds the jet occu- of the jet: modest equipment. pies in the sky. Our calculations show To do this, we first needed to know a plasma jet length of the resolution of our camera/tele- approximately 4,542 scope set, which is given by the fol- light-years, compared lowing formula: to the approximately 5,000 light-years calcu- R (arcseconds per pixel) lated by observatories 206 × size of the pixel (µ) with greater resolving focal length (mm) power or located out- side of the Earth’s at- In our case: mosphere. Similarly, we obtained the value . of 855.6 light-years for . the width of the jet,

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which is a combination of the highly collimated central rela- tivistic jet (much smaller in width) and the envelope of non-relativistic material sur- rounding it. We measured the size of an object located 53 million light- years from Earth, with an error of less than 500 light-years. The difference between our values and the official ones may be due to the fact that we likely were not capturing the

he jet of M87. OLA, 9 T March 2019. [M. Sánchez (SAG), A. Porcel (SAG/OLA)]

he La Laguna Astronomical Ob- T servatory is a structure dedi- cated to astronomical observation, research and dissemination in col- laboration with the Sociedad As- tronómica Granadina.

very end of the jet in our images, a region that is perhaps more nebu- lous than the rest. It is evident that it is possible to ob- tain measurements that correspond to professionally-obtained values with amateur instruments. This has opened our minds in two re- spects: firstly, and contrary to what one might think, it is relatively easy to find examples of mathematics ap- plied to astronomical observations made by amateurs, which can be ex- trapolated to educational centers or astronomical associations in the form of a laboratory exercise, where stu- dents or participants can experience firsthand how to gather evidence (images), extract data and apply the- ory to see how what sometimes ap- pears to us as something unattain- able can actually be reproducible and verifiable by ourselves. Secondly, it shows us that if these kinds of ob- servations are done rigorously, any- one can do good science, which is extremely motivating. !

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www.newmoontelescopes.com [email protected] magazine EN_Free Astronomy Magazine 28/04/2021 16:51 Page 36

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Most distant quasar with powerful radio jets discovered

by ESO - Bárbara Ferreira

ith the help of the Euro- around 780 million years old. While pean Southern Observa- more distant quasars have been dis- W tory’s Very Large Tele- covered, this is the first time as- scope (ESO’s VLT), astronomers have tronomers have been able to identify discovered and studied in detail the the telltale signatures of radio jets in most distant source of radio emis- a quasar this early on in the history sion known to date. The source is a of the Universe. Only about 10% of “radio-loud” quasar — a bright ob- quasars — which astronomers classify ject with powerful jets emitting at as “radio-loud” — have jets, which radio wavelengths — that is so far shine brightly at radio frequencies. away its light has taken 13 billion P172+18 is powered by a black hole years to reach us. about 300 million times more mas- The discovery could provide impor- sive than our Sun that is consuming tant clues to help astronomers un- gas at a stunning rate. “The black derstand the early Universe. hole is eating up matter very rapidly, Quasars are very bright objects that growing in mass at one of the high- lie at the centre of some galaxies est rates ever observed,” explains as- and are powered by supermassive tronomer Chiara Mazzucchelli, Fel- black holes. As the black hole con- low at ESO in Chile, who led the dis- sumes the surrounding gas, energy covery together with Eduardo Baña- is released, allowing astronomers to dos of the Max Planck Institute for spot them even when they are very Astronomy in Germany. far away. The astronomers think that there’s a The newly discovered quasar, nick- link between the rapid growth of su- named P172+18, is so distant that permassive black holes and the pow- light from it has travelled for about erful radio jets spotted in quasars like 13 billion years to reach us: we see it P172+18. The jets are thought to be as it was when the Universe was just capable of disturbing the gas around

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his artist’s impression shows T how the distant quasar P172+18 and its radio jets may have looked. To date (early 2021), this is the most distant quasar with radio jets ever found and it was studied with the help of ESO’s Very Large Telescope. It is so distant that light from it has travelled for about 13 billion years to reach us: we see it as it was when the Universe was only about 780 mil- lion years old. [ESO/M. Kornmesser]

the black hole, increasing the rate at other telescopes followed, including which gas falls in. Therefore, study- with the X-shooter instrument on ing radio-loud quasars can provide ESO’s VLT, which allowed them to important insights into how black dig deeper into the characteristics of holes in the early Universe grew to this quasar, including determining their supermassive sizes so quickly key properties such as the mass of after the Big Bang. “I find it very ex- the black hole and how fast it’s eat- citing to discover ‘new’ black holes ing up matter from its surroundings. for the first time, and to provide one Other telescopes that contributed to more building block to understand the study include the National Radio the primordial Universe, where we Astronomy Observatory’s Very Large come from, and ultimately our- Array and the Keck Telescope in the selves,” says Mazzucchelli. US. While the team are excited about P172+18 was first recognised as a far- their discovery, appeared in The As- away quasar, after having been pre- trophysical Journal, they believe this viously identified as a radio source, radio-loud quasar could be the first at the Magellan Telescope at Las of many to be found, perhaps at Campanas Observatory in Chile by even larger cosmological distances. Bañados and Mazzucchelli. “As soon “This discovery makes me optimistic as we got the data, we inspected it and I believe — and hope — that the by eye, and we knew immediately distance record will be broken that we had discovered the most dis- soon,” says Bañados. tant radio-loud quasar known so Observations with facilities such as far,” says Bañados. ALMA, in which ESO is a partner, and However, owing to a short observa- with ESO’s upcoming Extremely tion time, the team did not have Large Telescope (ELT) could help un- enough data to study the object in cover and study more of these early- detail. A flurry of observations with Universe objects in detail. !

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Hubble pinpoints supernova blast

by NASA/ESA Bethany Downer

he NASA/ESA Hubble Space Telescope has observed the su- T pernova remnant named 1E 0102.2-7219. Researchers are using Hubble’s imagery of the remnant ob- ject to wind back the clock on the ex- panding remains of this exploded star in the hope of understanding the supernova event that caused it 1700 years ago. The featured star that ex- ploded long ago belongs to the Small Magellanic Cloud, a satellite galaxy of our Milky Way located roughly 200,000 light-years away. The doomed star left behind an expand- ing, gaseous corpse — a supernova remnant — known as 1E 0102.2-7219.

Because the gaseous knots in this su- pernova remnant are moving at dif- ferent speeds and directions from the supernova explosion, those mov- ing toward Earth are colored blue in this composition and the ones mov- ing away are shown in red. This new Hubble image shows these ribbons of gas speeding away from

eft: pictured here is the region of L sky around the supernova rem- nant 1E 0102.2-7219. [ESA/Hubble, Digitized Sky Survey 2. Acknowl- edgement: Davide De Martin] Top: Hubble’s Distant View of the Supernova Remnant 1E 0102.2-7219 in 2006. [NASA, ESA and the Hubble Heritage Team (STScI/AURA)]

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eatured in this Hubble image is F an expanding, gaseous corpse — a supernova remnant — known as 1E 0102.2-7219. It is the remnant of a star that exploded long ago in the Small Magellanic Cloud, a satellite galaxy of our Milky Way located roughly 200,000 light-years away. [NASA, ESA, and J. Banovetz and D. Milisavljevic (Purdue University)]

the explosion site at an average speed of 3.2 million kilometers per hour. At that speed, you could travel to the Moon and back in 15 minutes. Researchers have studied the Hub- ble archive looking for visible-light images of the supernova remnant and they have analysed the data to calculate a more accurate estimate of the age and centre of the super- nova blast. According to their new estimates, light from this blast arrived at Earth 1700 years ago, during the decline of the Roman Empire. This super- nova would only have been visible to inhabitants of Earth’s southern hemisphere. Unfortunately, there are no known records of this titanic event. Earlier studies proposed ex- plosion dates of 2,000 and 1,000 years ago, but this new analysis is believed to be more robust. To pinpoint when the explosion oc- curred, researchers studied the tad- pole-shaped, oxygen-rich clumps of ejecta flung out by this supernova blast. Ionised oxygen is an excellent tracer because it glows brightest in visible light. By using Hubble’s pow- erful resolution to identify the 22 fastest moving ejecta clumps, or knots, the researchers determined long it took the speedy knots to million kilometres per hour from that these targets were the least travel from the explosion centre to the centre of the explosion to have likely to have been slowed down by their current location. arrived at its current position. The passage through interstellar mate- Hubble also measured the speed of suspected neutron star was identi- rial. They then traced the knots’ mo- a suspected neutron star — the fied in observations with the Euro- tion backward until the ejecta co- crushed core of the doomed star — pean Southern Observatory’s Very alesced at one point, identifying that was ejected from the blast. Large Telescope in Chile, in combi- the explosion site. Once that was Based on the researchers’ estimates, nation with data from NASA’s Chan- known, they could calculate how itmust be moving at more than 3 dra X-ray Observatory. !

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Deep dive into a galaxy cluster

by NOIRLab - Amanda Kocz

stronomers refer to observa- stunning long-exposure obser- tions as “deep” when they A vation lasting 70 minutes from A are taken with very long ex- the Nicholas U. Mayall 4-meter Tele- posure times. Just as with photogra- scope at Kitt Peak National Observa- phy, this gathers more light, reveal- tory, a Program of NSF’s NOIRLab, ing distant, fainter objects. reveals the spiral galaxy NGC 1003 in Deeper exposures let astronomers glorious detail. NGC 1003 resides in look deeper into the Universe — front of a galaxy cluster — a vast col- hence the name. This particular deep lection of galaxies bound together by image (right) was taken with a 70- gravity. The long exposure time of minute exposure with the Nicholas this deep observation allowed these U. Mayall 4-meter Telescope at Kitt usually overlooked red background Peak National Observatory, a Pro- cluster galaxies to be captured. gram of NSF’s NOIRLab, and captures [KPNO/NOIRLab/NSF/AURA - Ack: M.T. Patterson (New Mexico State Univer- the spiral galaxy NGC 1003. sity) - Image processing: Travis Rector NGC 1003 lies over 30 million light- (University of Alaska Anchorage), years from Earth in the direction of Mahdi Zamani & Davide de Martin] the constellation Perseus. While it

makes for a spectacular sight, it is only one of many galaxies captured in this image. Upon closer inspec- tion, other galaxies can also be seen strewn throughout the image, with everything from delicate spiral gal- axies to hundreds of fuzzy, red ellip-

ooming on NGC 1003 for press Z release noirlab2101: Deep Dive into a Galaxy Cluster. [KPNO/NOIR- Lab/NSF/AURA, S. Brunier/Digitized Sky Survey 2, E. Slawik. Image Pro- cessing: Travis Rector (University of Alaska Anchorage), Mahdi Zamani & Davide de Martin]

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tical galaxies lurking in the back- distinct galaxies, showing that our catching is the bright heart of the ground. The long exposure time of Universe is a surprisingly crowded galaxy, which is surrounded by this deep observation — arguably place. clouds of dense dust. the deepest image of NGC 1003 ever While the Hubble team deliberately NGC 1003 resides in front of a galaxy captured — allowed these usually avoided bright galaxies for their ob- cluster — a vast collection of galax- overlooked background cluster gal- servation, this ground-based obser- ies bound together by gravity. These axies to be captured in breathtaking vation is littered with galaxies of all structures are among the most mas- detail. shapes and sizes — a spectacular sive in the known Universe, and out- Deep images such as this one have backdrop for this portrait of NGC weigh the Sun by a factor of a thou- had an important role in shaping 1003. As well as revealing the host sand trillion. our understanding of the Universe. of background galaxies, the long Just as stars can be grouped into In 1995, the Hubble Space Telescope exposure time of this observation clusters, and these star clusters into famously observed a tiny, nonde- allowed the researchers to capture galaxies, galaxies themselves form script patch of sky for 10 days to cre- the faint outer reaches of NGC 1003, clusters and even superclusters — ate the Hubble Deep Field. The ob- which are threaded through with building up the large-scale structure servations revealed thousands of bright tendrils of stars. Equally eye- of our Universe. !

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42 ASTRO PUBLISHING

Six-exoplanet system challenges theories of how planets form

by ESO - Bárbara Ferreira

he first time an ESO team ob- words, they are in resonance. This served TOI-178, a star some means that there are patterns that T 200 light-years away in the repeat themselves as the planets go constellation of Sculptor, they around the star, with some planets thought they had spotted two plan- aligning every few orbits. A similar ets going around it in the same or- resonance is observed in the orbits bit. However, a closer look revealed of three of Jupiter’s moons: Io, Eu- something entirely different. ropa and Ganymede. Io, the closest “Through further observations we of the three to Jupiter, completes realised that there were not two four full orbits around Jupiter for planets orbiting the star at roughly every orbit that Ganymede, the fur- the same distance from it, but rather thest away, makes, and two full or- multiple planets in a very special con- bits for every orbit Europa makes. figuration,” says Adrien Leleu from The five outer exoplanets of the the Université de Genève and the TOI-178 system follow a much more University of Bern, Switzerland, who complex chain of resonance, one of led a new study of the system pub- the longest yet discovered in a sys- lished in Astronomy & Astrophysics. tem of planets. While the three The new research has revealed that Jupiter moons are in a 4:2:1 reso- the system boasts six exoplanets and nance, the five outer planets in the that all but the one closest to the TOI-178 system follow a 18:9:6:4:3 star are locked in a rhythmic dance chain: while the second planet from as they move in their orbits. In other the star (the first in the resonance

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chain) completes 18 orbits, the third his artist’s impression shows the T view from the planet in the TOI- planet from the star (second in the 178 system found orbiting furthest chain) completes 9 orbits, and so on. from the star. New research by In fact, the scientists initially only Adrien Leleu and his colleagues with found five planets in the system, but several telescopes, including ESO’s by following this resonant rhythm Very Large Telescope, has revealed they calculated where in its orbit an that the system boasts six exoplan- additional planet would be when ets and that all but the one closest they next had a window to observe to the star are locked in a rare the system. rhythm as they move in their orbits. More than just an orbital curiosity, But while the orbital motion in this system is in harmony, the physical this dance of resonant planets pro- properties of the planets are more vides clues about the system’s past. disorderly, with significant varia- “The orbits in this system are very tions in density from planet to well ordered, which tells us that this planet. This contrast challenges as- system has evolved quite gently tronomers’ understanding of how since its birth,” explains co-author planets form and evolve. This artist’s Yann Alibert from the University of impression is based on the known Bern. If the system had been signif- physical parameters for the planets icantly disturbed earlier in its life, and the star seen, and uses a vast for example by a giant impact, database of objects in the Universe. [ESO/L. Calçada/spaceengine.org] this fragile configuration of orbits would not have survived.

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planet as dense as the Earth right mony of the orbital motion and the rtist’s representation of the or- A bits of the planets in the TOI- next to a very fluffy planet with half disorderly densities certainly chal- 178 system. [ESO/L. Calçada] the density of Neptune, followed by lenges our understanding of the for- a planet with the density of Nep- mation and evolution of planetary But even if the arrangement of the tune. It is not what we are used to.” systems,” says Leleu. orbits is neat and well-ordered, the In our Solar System, for example, the To investigate the system’s unusual densities of the planets “are much planets are neatly arranged, with architecture, the team used data more disorderly,” says Nathan Hara the rocky, denser planets closer to from the European Space Agency’s from the Université de Genève, the central star and the fluffy, low- CHEOPS satellite, alongside the Switzerland, who was also involved density gas planets farther out. “This ground-based ESPRESSO instrument in the study. “It appears there is a contrast between the rhythmic har- on ESO’s VLT and the NGTS and

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45

his animation shows a representation of the orbits and movements of the T planets in the TOI-178 system. New research by Adrien Leleu and his col- leagues with several telescopes, including ESO’s Very Large Telescope, has re- vealed that the system boasts six exoplanets and that all but the one closest to the star are locked in a rare rhythm as they move in their orbits (represented in orange). In other words, they are in resonance. This means that there are pat- terns that repeat themselves rhythmically as the planets go around the star, with some planets aligning every few orbits. In this artist’s animation, the rhythmic movement of the planets around the central star is represented through a musical harmony, created by attributing a note (in the pentatonic scale) to each of the planets in the resonance chain. This note plays when a planet completes either one full orbit or one half orbit; when planets align at these points in their orbits, they ring in resonance. [ESO/L. Calçada]

and radial velocities — observing Some of the planets are rocky, but the star’s light spectrum for small larger than Earth — these planets signs of wobbles which happen as are known as Super-Earths. Others the exoplanets move in their orbits. are gas planets, like the outer plan- The team used both methods to ets in our Solar System, but they are observe the system: CHEOPS, NGTS much smaller — these are nick- and SPECULOOS for transits and named Mini-Neptunes. ESPRESSO for radial velocities. Although none of the six exoplanets By combining the two techniques, found lies in the star’s habitable astronomers were able to gather zone, the researchers suggest that, key information about the system by continuing the resonance chain, SPECULOOS, both sited at ESO’s and its planets, which orbit their they might find additional planets Paranal Observatory in Chile. Since central star much closer and much that could exist in or very close to exoplanets are extremely tricky to faster than the Earth orbits the Sun. this zone. ESO’s Extremely Large Tel- spot directly with telescopes, as- The fastest (the innermost planet) escope (ELT), which is set to begin tronomers must instead rely on completes an orbit in just a couple operating this decade, will be able other techniques to detect them. of days, while the slowest takes to directly image rocky exoplanets in The main methods used are imaging about ten times longer. The six plan- a star’s habitable zone and even transits — observing the light emit- ets have sizes ranging from about characterise their atmospheres, pre- ted by the central star, which dims as one to about three times the size of senting an opportunity to get to an exoplanet passes in front of it Earth, while their masses are 1.5 to know systems like TOI-178 in even when observed from the Earth — 8 times the mass of Earth. greater detail. !

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Doubling the number of known gravitational lenses

by NOIRLab-Amanda Kocz dicted that this warping of space- notice this effect. Only when a gal- time might be observable, as a axy is hidden directly behind a giant stronomers hunting for stretching and distortion of the light galaxy is a lens possible to see,” gravitational lenses utilized from a background galaxy by a fore- notes the lead author of the study, A machine learning to inspect ground cluster of galaxies. Xiaosheng Huang from the Univer- the vast dataset known as the DESI The lenses typically appear in images sity of San Francisco. “When we Legacy Imaging Surveys, uncovering as arcs and streaks around fore- started this project in 2018, there 1,210 new lenses. The data were col- ground galaxies and galaxy clusters. were only about 300 confirmed lected at Cerro Tololo Inter-Ameri- Only 1 in 10,000 massive galaxies are strong lenses.” can Observatory (CTIO) and Kitt expected to show evidence of strong “As a co-leader in the DESI Legacy Peak National Observatory (KPNO), gravitational lensing, and locating Surveys, I realized this would be the both Programs of the National Sci- them is not easy. Gravitational lenses perfect dataset to search for gravi- ence Foundation’s NOIRLab. The allow astronomers to explore the tational lenses,” explains study co- ambitious DESI Legacy Imaging Sur- most profound questions of our Uni- author David Schlegel of Lawrence veys just had its ninth and final data verse, including the nature of dark Berkeley National Laboratory (LBNL). release. matter and the value of the Hubble “My colleague Huang had just fin- Discussed in scientific journals since constant, which defines the expan- ished teaching an undergraduate the 1930s, gravitational lenses are sion of the Universe. A major limita- class on machine learning at the products of Einstein’s General The- tion of the use of gravitational University of San Francisco, and to- ory of Relativity. The theory says that lenses until now has been the small gether we realized this was a per- a massive object, such as a cluster of number of them known. fect opportunity to apply those galaxies, can warp spacetime. Some “A massive galaxy warps the space- techniques to a search for gravita- scientists, including Einstein, pre- time around it, but usually you don’t tional lenses.”

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ready yielded more than a thousand brain and are used for solving arti- xamples of gravitational lenses E found in the DESI Legacy Survey new gravitational lenses, and there ficial intelligence problems. Deep data. [DESI Legacy Imaging Surveys/ are undoubtedly many more await- neural nets have many layers that LBNL/DOE & KPNO/CTIO/NOIRLab/ ing discovery.” collectively can decide whether a NSF/AURA] The DESI Legacy Imaging Surveys candidate object belongs to a par- data are served to the astronomical ticular group. In order to be able to The lensing study was possible be- community via the Astro Data Lab do this, however, the neural nets cause of the availability of science- at NOIRLab’s Community Science have to be trained to recognize the ready data from the DESI Legacy and Data Center (CSDC). objects in question. Imaging Surveys, which were con- “Providing science-ready datasets With the large number of lens can- ducted to identify targets for DESI’s for discovery and exploration is core didates now on hand, researchers operations, and from which the to our mission,” said CSDC Director can make new measurements of ninth and final dataset has just been Adam Bolton. “The DESI Legacy Im- cosmological parameters such as the released. These surveys comprise a aging Surveys is a key resource that Hubble constant. The key will be to unique blend of three projects that can be used for years to come by the detect a supernova in the back- have observed a third of the night astronomy community for investiga- ground galaxy, which, when lensed sky: the Dark Energy Camera Legacy tions like these.” by a foreground galaxy, will appear Survey (DECaLS), observed by the To analyze the data, Huang and as multiple points of light. Now that DOE-built Dark Energy Camera team used the National Energy Re- astronomers know which galaxies (DECam) on the Víctor M. Blanco 4- search Scientific Computer Center’s show evidence for strong lensing, meter Telescope at CTIO in Chile; (NERSC) supercomputer at Berkeley they know where to search. the Mayall z-band Legacy Survey Lab. “The DESI Legacy Imaging Sur- New facilities such as the Vera C. (MzLS), by the Mosaic3 camera on veys were absolutely crucial to this Rubin Observatory (currently under the Nicholas U. Mayall 4-meter Tel- study; not just the telescopes, in- construction in Chile and operated escope at KPNO; and the Beijing- struments, and facilities but also by NOIRLab) will monitor objects Arizona Sky Survey (BASS) by the data reduction and source extrac- like these as part of its mission, al- 90Prime camera on the Bok 2.3- tion,” explains Huang. “The combi- lowing any supernova to be meas- meter Telescope, which is owned nation of the breadth and depth of ured rapidly by other telescopes. and operated by the University of the observations is unparalleled.” Undergraduate students played a Arizona and located at KPNO. With the huge amount of science- significant role in the project from “We designed the Legacy Surveys ready data to work through, the its beginning. University of Califor- imaging project from the ground up researchers turned to a kind of ma- nia student Andi Gu said, “My role as a public enterprise, so that it chine learning known as a deep on the project has helped me de- could be used by any scientist,” said residual neural net. Neural nets are velop several skills which I believe study co-author Arjun Dey, from computing algorithms that are to be key for my future academic NSF’s NOIRLab. “Our survey has al- somewhat comparable to a human career.” !

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48 ASTRO PUBLISHING

Hubble showcases six galaxy mergers

by NASA/ESA Bethany Downer NGC 3256 NGC 1614

o celebrate a new year, the NASA/ESA Hubble Space Tele- T scope has published a mon- tage of six beautiful galaxy mergers. Each of these merging systems was studied as part of the recent HiPEEC survey to investigate the rate of new star formation within such systems. These interactions are a key aspect of galaxy evolution and are among the most spectacular events in the NGC 3690 NGC 6052 lifetime of a galaxy. It is during rare merging events that galaxies undergo dramatic changes in their appearance and in their stel- lar content. These systems are excel- lent laboratories to trace the forma- tion of star clusters under extreme physical conditions. The Milky Way typically forms star clusters with masses that are 10 thousand times the mass of our Sun. This doesn’t compare to the masses of the star clusters forming in collid- ing galaxies, which can reach mil- lions of times the mass of our Sun. These dense stellar systems are also very luminous. Even after the colli- sion, when the resulting galactic system begins to fade into a more quiescent phase, these very massive

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star clusters will shine throughout that drastically increase the rate at masses, and extinctions and to an- their host galaxy, as long-lasting wit- which new stars are formed in these alyse the star formation rate within nesses of past merging events. galaxies. Hubble’s capabilities have these six merging galaxies. By studying the six galaxy mergers made it possible to resolve large The HiPEEC study reveals that the shown here, the Hubble imaging star-forming “knots” into numerous star cluster populations undergo Probe of Extreme Environments and compact young star clusters. Hub- large and rapid variations in their Clusters (HiPEEC) survey has investi- ble’s ultraviolet and near-infrared properties, with the most massive gated how star clusters are affected observations of these systems have clusters formed towards the end of during collisions by the rapid changes been used to derive star cluster ages, the merger phase. !

NGC 4194

NGC 34

[NASA & ESA]

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Solar System’s most distant known object confirmed

by NOIRLab - Amanda Kocz

ith the help of the inter- NOIRLab, and other ground-based in 2018 and nicknamed “Farfarout” national Gemini Observa- telescopes, astronomers have con- is indeed the most distant object yet W tory, a Program of NSF’s firmed that a faint object discovered found in our Solar System. magazine EN_Free Astronomy Magazine 28/04/2021 16:51 Page 51

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It was first spotted in January 2018 coverer Scott Sheppard of the his illustration depicts the most by the Subaru Telescope, located on Carnegie Institution for Science. “All T distant object yet found in our Maunakea in Hawai’i. Its discoverers we knew was that the object ap- Solar System, nicknamed “Farfar- could tell it was very far away, but peared to be very distant at the out,” in the lower right. In the they weren’t sure exactly how far. time of discovery.” lower left, a graph shows the dis- They needed more observations. Sheppard and his colleagues, David tances of the planets, dwarf plan- “At that time we did not know the Tholen of the University of Hawai’i ets, candidate dwarf planets, and object’s orbit as we only had the and Chad Trujillo of Northern Ari- Farfarout from the Sun in astro- Subaru discovery observations over zona University, spent the next few nomical units (au). One au is equal to Earth’s average distance from the 24 hours, but it takes years of obser- years tracking the object with the Sun. Farfarout is 132 au from the vations to get an object’s orbit Gemini North telescope (also on Sun. [NOIRLab/NSF/AURA/J. da Silva] around the Sun,” explained co-dis- Maunakea in Hawai’i) and the magazine EN_Free Astronomy Magazine 28/04/2021 16:51 Page 52

52 ASTRO PUBLISHING

hese discovery images of Farfarout (2018 AG37) were taken with the Subaru Telescope on the nights of 15 and 16 Janu- T ary 2018 Universal Time (UT). By comparing the images with each other, it is possible to see that Farfarout (marked by blue horizontal lines) moves while the background stars and galaxies do not. [S. Sheppard]

Carnegie Institution for Science’s too close to Neptune in the distant eral years of observations to pre- Magellan Telescopes in Chile to de- past,” said Trujillo. “Farfarout will cisely determine its trajectory.” termine its orbit. They have now likely interact with Neptune again in Farfarout’s discoverers are confident confirmed that Farfarout currently the future since their orbits still in- that even more distant objects re- lies 132 astronomical units (au) from tersect.” main to be discovered on the out- the Sun, which is 132 times farther Farfarout is very faint. Based on its skirts of the Solar System, and that from the Sun than Earth is. (For com- brightness and distance from the its distance record might not stand parison, Pluto is 39 au from the Sun, Sun, the team estimates it to be for long. on average.) about 400 kilometers (250 miles) “The discovery of Farfarout shows Farfarout is even more remote than across, putting it at the low end of our increasing ability to map the the previous Solar System distance possibly being designated a dwarf outer Solar System and observe far- record-holder, which was discovered planet by the International Astro- ther and farther towards the by the same team and nicknamed nomical Union (IAU). fringes of our Solar System,” said “Farout.” Provisionally designated The IAU’s Minor Planet Center in Sheppard. “Only with the advance-

2018 VG18, Farout is 124 au from the Massachusetts announced that it has ments in the last few years of large Sun. However, the orbit of Farfarout given Farfarout the provisional des- digital cameras on very large tele-

is quite elongated, taking it 175 au ignation 2018 AG37. The Solar Sys- scopes has it been possible to effi- from the Sun at its farthest point tem’s most distant known member ciently discover very distant objects and around 27 au at its closest, will receive an official name after like Farfarout. Even though some which is inside the orbit of Neptune. more observations are gathered and of these distant objects are quite Because its orbit crosses Nep- tune’s, its orbit becomes even more refined large — the size of dwarf planets — Farfarout could provide insights in the coming years. they are very faint because of their into the history of the outer Solar “Farfarout takes a millennium to go extreme distances from the Sun. System. around the Sun once,” said Tholen. Farfarout is just the tip of the ice- “Farfarout was likely thrown into “Because of this, it moves very berg of objects in the very distant the outer Solar System by getting slowly across the sky, requiring sev- Solar System.” !

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Monte Bianco Cableways: the dream of bringing man closer to the mountains and the sky.

A structure challenging the laws of nature, where the view from above seems to go on forever. An idea making it possible to broaden horizons and overcome borders. All of this is Skyway Monte Bianco.

www.montebianco.com/en cover EN.qxp_l'astrofilo 28/04/2021 16:52 Page 54

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