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Kepler-452B Is Not a New Earth a Twin of the Sun-Jupiter System

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Kepler-452B Is Not a New Earth a Twin of the Sun-Jupiter System cover EN:l'astrofilo 28/08/15 10:12 Page 1 THE FREE MULTIMEDIA MAGAZINE THAT KEEPS YOU UPDATED ON WHAT IS HAPPENING IN SPACE Bi-monthly magazine of scientific and technical information ✶ September-October 2015 issue astonishing PLUTO Kepler-452b is not a new Earth A twinofthe Sun-Jupiter system www.astropublishing.com ✶ ita.astropublishing.com ✶ [email protected] colophon EN:l'astrofilo 28/08/15 10:17 Page 3 SUMMARY BI-MONTHLY MAGAZINE OF SCIENTIFIC AND TECHNICAL INFORMATION Astonishing Pluto FREELY AVAILABLE THROUGH A faultless mission, that of New Horizons: after a journey of nine and a half years it finally made its THE INTERNET rendezvous with Pluto one minute earlier than predicted and performed its task in the best of ways, 4 revealing a world remarkably more lively and varied than we could have imagined. In these pages... September-October 2015 Kepler-452b is not a new Earth Discovering a planet very similar to ours, at just the right distance from a star identical to the Sun, would be an important step forward in the search for extraterrestrial life. The rush to reach this goal 18 could, however, make us overly optimistic and lead us to define the same as Earth a planet that in... First detection of lithium from an exploding star The light chemical element lithium is one of the few elements that is predicted to have been created by the Big Bang, 13.8 billion years ago. But understanding the amounts of lithium observed in stars around 26 us today in the Universe has given astronomers headaches. Older stars have less lithium than expected... The ghost of a dying star Nicknamed the Southern Owl Nebula, this shimmering orb is a planetary nebula with a diameter of almost four light-years. Its informal name relates to its visual cousin in the northern hemisphere, the Owl Nebula. 30 ESO 378-1, which is also catalogued as PN K 1-22 and PN G283.6+25.3, is located in the constellation of... English edition of the magazine l’ASTROFILO Early black hole could upend evolutionary theory An international team of astrophysicists led by Benny Trakhtenbrot, a researcher at ETH Zurich’s Insti- Editor in chief tute for Astronomy, discovered a gigantic black hole in an otherwise normal galaxy, using W. M. Keck Michele Ferrara 32 Observatory’s 10-meter, Keck I telescope in Hawaii. The team, conducting a fairly routine hunt for... Scientific advisor Prof. Enrico Maria Corsini A twin of the Sun-Jupiter system Publisher Astro Publishing di Pirlo L. With its mass and orbital position, Jupiter has always had a decisive role in the evolution of the planetary Via Bonomelli, 106 system architecture. Not only has it fostered the birth of a planet such as Earth, but it also appears to 25049 Iseo - BS - ITALY have indirectly contributed to making it liveable. Now astronomers have discovered an almost identical... email [email protected] 38 Internet Service Provider Aruba S.p.A. Best evidence of first generation stars in the universe Loc. Palazzetto, 4 52011 Bibbiena - AR - ITALY Astronomers have long theorised the existence of a first generation of stars — known as Population III stars — that were born out of the primordial material from the Big Bang. The name Population III Copyright arose because astronomers had already classed the stars of the Milky Way as Population I (stars like... All material in this magazine is, unless 44 otherwise stated, property of Astro Publishing di Pirlo L. or included with permission of its author. Reproduction Atmosphere stripped from Neptune-sized exoplanet or retransmission of the materials, in whole or in part, in any manner, with- Astronomers using the NASA/ESA Hubble Space Telescope have discovered an immense cloud of hy- out the prior written consent of the drogen dispersing from a warm, Neptune-sized planet orbiting a nearby star. The enormous gaseous copyright holder, is a violation of tail of the planet is about 50 times the size of the parent star. A phenomenon this large has never... copyright law. A single copy of the 46 materials available through this course may be made, solely for personal, non- commercial use. Users may not distrib- ute such copies to others, whether or Fossil star clusters reveal their age not in electronic form, whether or not Using a new age-dating method and the W. M. Keck Observatory on Maunakea, an international team for a charge or other consideration, of astronomers have determined that ancient star clusters formed in two distinct epochs – the first 12.5 without prior written consent of the billion years ago and the second 11.5 billion years ago. Although the clusters are almost as old as the... copyright holder of the materials. 49 The publisher makes available itself with having rights for possible not characterized iconographic sources. Uranus-sized planet discovered through microlensing Advertising - Administration NASA's Hubble Space Telescope and the W. M. Keck Observatory in Hawaii have made independent Astro Publishing di Pirlo L. confirmations of an exoplanet orbiting far from its central star. The planet was discovered through a Via Bonomelli, 106 technique called gravitational microlensing. This finding opens a new piece of discovery space in the... 25049 Iseo - BS - ITALY 52 email [email protected] plutone EN:l'Astrofilo 28/08/15 10:18 Page 4 4 PLANETOLOGY AstonishingAstonishing PlutoPluto by Michele Ferrara A faultless mission, that of New Horizons: nly Pluto was still missing for complet- after a journey of nine and a half years it O ing the initial recon- naissance of the solar sys- finally made its rendezvous with Pluto one tem, and the primary goal minute earlier than predicted and perform- of NASA's New Horizons mission was precisely to fill ed its task in the best of ways, revealing a this gap. Compared to earlier world remarkably more lively and varied achievements by other space- crafts, this seemed a far minor objec- than we could have imagined. In these tive, so much so that hardly anyone ex- pages, we offer our readers a preview of the pected to see anything more than a dark globe crystallized by some billions of new face of Pluto and some of its satellites. years, at most marked by impacts of small SEPTEMBER-OCTOBER 2015 plutone EN:l'Astrofilo 28/08/15 10:19 Page 5 PLANETOLOGY 5 inging PlutoPluto July 2015, New Horizons 14 encounters Pluto and its satellites’ system. [JHUAPL/SwRI] SEPTEMBER-OCTOBER 2015 plutone EN:l'Astrofilo 28/08/15 10:19 Page 6 6 PLANETOLOGY bodies, definitely not common in that desolate part of our sys- tem. Pluto has instead turned out to be a remarkably diversified (dwarf) the planet, after having already travelled July, the sur- planet, with an atmosphere more similar more than 5 billion km in 9 and a half 11 faces of Plu- to that of Earth’s in terms of nitrogen con- years. With a resolution of 27 km/pixel, to (above) and tent percentage, but, above all, to be geo- this image allows to observe details barely Charon (below) logically active. hinted in the previous days’ recordings: clearly reveal the presence of cra- Evidence of this unexpected fact first the surface appears very varied, with large ters, chasms and emerged from a picture of Pluto taken on areas of different albedo and diverse cra- troughs. [NASA/ 9 July by the Long Range Reconnaissance tering levels. The surface structure more Johns Hopkins Imager (LORRI) of New Horizons, when University Ap- the spacecraft was still 5.4 million km from plied Physics Lab- oratory/South- west Research Institute] SEPTEMBER-OCTOBER 2015 plutone EN:l'Astrofilo 28/08/15 10:19 Page 7 PLANETOLOGY 7 July, New Ho- markedly visible in this image is 11 rizons cap- a long dark region lying on tures, from a dis- the equator, provisionally tance of 4 million called “whale” due to its km, the best ever odd shape. Of partic- image of the op- ular scientific inter- posite hemisphere to that of the fly- est immediately ap- by. [NASA/Johns peared the tran- Hopkins Univer- sition territories sity Applied Phys- between the ics Laboratory/ “whale’s tail” and Southwest Re- the planet’s search Institute] western edge, where for the first time were noticed some unusual polygo- nal formations, that in the next 14 July flyby would not be possible to observe in detail, since located in the opposite hemi- sphere to that framed by the spacecraft’s instruments. On 11 July, at a distance of 4 mil- lion km from Pluto, LORRI photographs the hemisphere constantly facing Charon 500 km each, all arranged along the equa- (the one not visible during the flyby) and tor and adjacent to the “whale”. Already acquires the best ever picture of 4 large glimpsed during previous recordings, they areas, apparently circular and wide nearly now show a complex structure that leaves us uncertain as to their nature. That image will remain for decades the best ever image of the hemisphere not covered by the New Horizons’ flyby. July, Pluto and Charon 13 photographed in colour, later enhanced to highlight terrains of varying composition. The distance between the two objects has been reduced. [NASA/Johns Hopkins University Applied Physics Laboratory/ Southwest Research Institute] SEPTEMBER-OCTOBER 2015 plutone EN:l'Astrofilo 28/08/15 10:19 Page 8 8 PLANETOLOGY Always on 11 July, the spacecraft turns its a hundred kilometres across and its bright July, the instruments also on Charon, showing a ejecta suggest that it must have formed 13 LORRI in- surface pockmarked with chasms and cra- over the last billion years.
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