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Free Astronomy Magazine March-April 2018 cover EN.qxp_l'astrofilo 27/02/2018 17:01 Page 1 THE FREE MULTIMEDIA MAGAZINE THAT KEEPS YOU UPDATED ON WHAT IS HAPPENING IN SPACE Bi-monthly magazine of scientific and technical information ✶ March-April 2018 issue News from the TRAPPIST-1 system ExTrA goes into action • ESO’s VLT working as 16-metre telescope for first time • Keck Observatory achieves first light with NIRES • Giant bubbles on red giant star’s surface • First ELT main mirror segments successfully cast • SMBHs−host galaxies co-evolution deepened by ALMA AWR star at the origin of the Solar System www.astropublishing.com ✶ www.astropublishing.org ✶ [email protected] colophon EN_l'astrofilo 27/02/2018 17:03 Page 2 Ritchey-Chrétien 250 mm f/8.5 Suprax OPTICS FROM Schott CARBON STRUCTURE NortheK CELL StabilobloK 25 FOCUSER Feather Touch FTF 2000 2" WEIGHT 15 kg. www.northek.it - www.facebook.com/northek.it - [email protected] - phone +39 01599521 colophon EN_l'astrofilo 27/02/2018 17:03 Page 3 S U M M A R Y BI-MONTHLY MAGAZINE OF SCIENTIFIC AND TECHNICAL INFORMATION News from the TRAPPIST-1 system FREELY AVAILABLE THROUGH In the last year, many studies dedicated to the extraordinary TRAPPIST-1's planetary system have been THE INTERNET realised and published. Sometimes, works published a short distance from each other have described antithetical scenarios, but as a whole, the efforts made by researchers portrayed that system even... March-April 2018 4 ESO’s VLT working as 16-metre telescope for first time One of the original design goals of ESO’s Very Large Telescope (VLT) was for its four Unit Telescopes (UTs) to work together to create a single giant telescope. With the first light of the ESPRESSO spectrograph 14 using the four-Unit-Telescope mode of the VLT, this milestone has now been reached. After extensive... Keck Observatory achieves first light with NIRES Astronomers at W. M. Keck Observatory have successfully met a major milestone after capturing the very first science data from Keck Observatory’s newest instrument, the Caltech-built Near-Infrared Echel- 20 lette Spectrometer (NIRES). The Keck Observatory-Caltech NIRES team just completed the instrument’s... A Wolf-Rayet star at the origin of the Solar System We know the way many structures in the universe evolved following their origin, but in many cases we have not yet understood which phenomenon produced the origin itself. This is the case with our Solar 22 System, for which the dominant thinking is that it was born because of a shock wave from a supernova... English edition of the magazine lA’ STROFILO Researchers catch supermassive black hole burping−twice Astronomers have caught a supermassive black hole in a distant galaxy snacking on gas and then “burp- Editor in chief ing” — not once, but twice. The galaxy under study, called SDSS J1354+1327 (J1354 for short), is about Michele Ferrara 32 800 million light-years from Earth. The team used observations from NASA’s Hubble Space Telescope... Scientific advisor Prof. Enrico Maria Corsini Giant bubbles on red giant star’s surface Publisher Astro Publishing di Pirlo L. Located 530 light-years from Earth in the constellation of Grus (The Crane), π1 Gruis is a cool red giant. Via Bonomelli, 106 It has about the same mass as our Sun, but is 350 times larger and several thousand times as bright. 25049 Iseo - BS - ITALY Our Sun will swell to become a similar red giant star in about five billion years. An international team... email [email protected] 34 Internet Service Provider Aruba S.p.A. ExTrA goes into action Via San Clemente, 53 24036 Ponte San Pietro - BG - ITALY A strategic instrument has become operative in the search for Earth-like planets orbiting red dwarf stars located at relatively short distances from us. Its name is ExTrA. From the ground, it will be able to dis- Copyright cover planets as small as other telescopes can detect from space, and it will help to compile a list of... All material in this magazine is, unless 38 otherwise stated, property of Astro Publishing di Pirlo L. or included with permission of its author. Reproduction or retransmission of the materials, in The archaeology of our Milky Way’s ancient hub probed by Hubble whole or in part, in any manner, with- For many years, astronomers had a simple view of our Milky Way’s central hub, or bulge, as a quiescent out the prior written consent of the place composed of old stars, the earliest homesteaders of our galaxy. However, because the inner Milky copyright holder, is a violation of copy- Way is such a crowded environment, it has always been a challenge to disentangle stellar motions... right law. A single copy of the materi- 46 als available through this course may be made, solely for personal, noncom- mercial use. Users may not distribute such copies to others, whether or not First ELT main mirror segments successfully cast in electronic form, whether or not for The 39-metre-diameter primary mirror of ESO’s Extremely Large Telescope will be by far the largest ever a charge or other consideration, with- made for an optical-infrared telescope. Such a giant is much too large to be made from a single piece out prior written consent of the copy- of glass, so it will consist of 798 individual hexagonal segments, each measuring 1.4 metres across and... right holder of the materials. The 48 publisher makes available itself with having rights for possible not charac- terized iconographic sources. SMBHs−host galaxies co-evolution deepened by ALMA Advertising - Administration Using the Atacama Large Millimeter/submillimeter Array (ALMA) to observe an active galaxy with a strong Astro Publishing di Pirlo L. ionized gas outflow from the galactic center, astronomers have obtained a result making themselves Via Bonomelli, 106 even more puzzled: an unambiguous detection of carbon monoxide (CO) gas associated with the... 25049 Iseo - BS - ITALY 50 email [email protected] trappist1 EN_l'Astrofilo 27/02/2018 16:58 Page 4 4 EXOPLANETS News from the system by Michele Ferrara In the last year, many studies dedicated to the extraordinary TRAPPIST-1's planetary system have been realised and published. Sometimes, works published a short distance from one another have described antithetical scenarios, but as a whole, the efforts made by researchers portrayed the system as even more interesting. MARCH-APRIL 2018 trappist1 EN_l'Astrofilo 27/02/2018 16:58 Page 5 EXOPLANETS 5 TRAPPIST-1 TRAPPIST-1 his artist’s impression compares the seven planets orbiting the rom time to time it is unavoidable to go T ultra-cool red dwarf star TRAPPIST-1 to the Earth at the same back to talking about TRAPPIST-1, a decid- scale. New observations, when combined with very sophisticated F edly dwarf and relatively cold star, around analysis, have now yielded good estimates of the densities of all which there are as many as seven planets of a seven of the Earth-sized planets and suggest that they are rich in size comparable to that of Earth’s. We had al- volatile materials, probably water. They are shown to the same ready talked about this system a couple of years scale but not in the correct relative positions. [ESO/M. Kornmesser] ago (2016; 4), on the occasion of the discovery MARCH-APRIL 2018 trappist1 EN_l'Astrofilo 27/02/2018 16:58 Page 6 of the first three planets. Then again a to give an update on the leading news his infographic year ago (2017; 2), when we reported the concerning the system in the last year, in- T compares the discovery of the other four, and the possi- cluding the most recent and exciting stud- TRAPPIST-1 plane- bility that above some water may exist and ies published in specialised magazines. tary system with therefore an environment perhaps favour- We were left with uncertainties regarding the inner Solar Sys- tem and the four able to life as we know it. Now, we want the distance from the star of the outermost Galilean moons of the planet Jupiter. Left, this diagram compares the masses and energy input of the seven TRAPPIST-1 plan- ets, along with the properties of the four innermost Solar System plan- ets. [NASA/JPL- Caltech] MARCH-APRIL 2018 trappist1 EN_l'Astrofilo 27/02/2018 16:58 Page 7 his diagram planet, TRAPPIST-1h, a fundamental para- TRAPPIST-1h was found to be 18.76 days, T compares the meter to understand whether liquid water which corresponds to an average distance sizes, masses and can exist in that world (admitted and not from the star of 9.27 million km, too exces- estimated tem- granted that there is water). A team of re- sive to suppose that liquid water can exist peratures of the searchers, led by Rodrigo Luger of the Uni- on that planet. Thus, the Luger team ex- TRAPPIST-1 plan- ets with Solar versity of Washington, intervened to solve cluded the farthest planet from the TRAP- System planets. the problem. In an article published in Na- PIST-1’s habitable zone, after the two The colours indi- ture Astronomy last May, the team reports closest ones, TRAPPIST-1b and TRAPPIST-1c, cate temperatures the results of processing the photometric had already been considered uninhabit- and the black line data of TRAPPIST-1 collected by the Kepler able, not only for the maximum surface matches the den- space telescope between December 2016 temperatures (higher than 100°C), but also sities and compo- and March 2017. because their rotation periods are surely sition of the ter- In this period, known as K2 Campaign 12, synchronized with their revolution peri- restrial planets in Kepler monitored the small star for 74 ods, which leads them to always expose the Solar System.
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