All About Space No. 104의 목차

Welcome © Getty This month All About Space investigates when we're likely to see first light at the European Southern Observatory's (ESO) Extremely Large Telescope, or ELT, currently under construction in the dry, arid Atacama Desert in northern Chile. To get the best views possible the ELT will sit atop the Cerro Armazones mountain. Currently ESO astronomers have revealed we're likely to see some kind of operational movement in 2025 where, as you'll discover this issue, the megastructure – which consists of a 39.3-metre (130-foot) diameter segmented primary mirror and a 4.2-metre (14-foot) diameter secondary mirror – will advance our astrophysical knowledge. I'm of course talking about furthering our studies of planets around other stars, looking back to the very first galaxies in the cosmos, getting a better handle on…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE Strange ingredient in interstellar comet Borisov offers a clue to its origins Words by Chelsea Gohd ©ALMA Astronomers have revealed the unusual chemical composition inside 2I/ Borisov, the interstellar comet that visited our Solar System last year. A strange ingredient has provided new clues about where this travelling space rock originated from. 2I/Borisov was discovered on 30 August 2019 by amateur astronomer Gennady Borisov. Following the appearance of interstellar object ‘Oumuamua in 2017, this was the second object from another solar system ever discovered wandering through our cosmic neighbourhood. In December 2019 astronomers took a closer look at 2I/Borisov using the Atacama Large Millimeter/submillimeter Array (ALMA), a giant radio telescope in Chile. In the new study an international team of researchers, led…

Black hole keeps snacking on white dwarf locked in its orbit © NASA An astronomer thinks he’s spotted a stellar corpse – known as a white dwarf – sending out blazes of light: mayday signals from its uncomfortably close orbit of a black hole. And while such a white dwarf is usually the result of a star naturally running out of fuel and exploding, it’s thought the black hole itself snatched all of a red giant’s free gas away, triggering the premature death. Such is the peril of treading too close to a black hole, even if it can’t gobble you up. “In my interpretation of the X-ray data, the white dwarf survived, but it did not escape,” Andrew King, an astrophysicist at the University of Leicester in the UK,…

Rise of the super telescope RISE OF THE SUPER TEIESCIOPE As work continues on its design and construction, we take you inside the Extremely Large Telescope as it prepares for first light Reported by Dominic Reseigh-Lincoln © ESO; Getty Looking further and deeper than ever before… that’s the central goal that’s driven astronomy since its inception. Studying the night sky and the universe that frames our world in ever-increasing detail, dissecting the light that’s reaching our little world and discerning the grand legacy of the cosmos. For centuries humans have been building more and more powerful terrestrial telescopes that can see further into the void of space, each one expanding in size and breadth of vision. That ever-increasing scale and desire to know more has brought us to the Extremely…

The biggest eye on the sky Based in the Chilean Atacama Desert, the ELT will be the largest and most impressive telescope ever constructed by humans © ESO Creating the world’s largest telescope is no mean feat – it is one that requires a viable site as well as primary and secondary mirrors big enough to see further into space than we’ve ever seen from an Earthly lens. That’s why the ELT has been a global initiative, with a huge roster of countries providing materials, research and consultation on its design and construction. Since the ELT will form part of the European Southern Observatory network, a site in Chile was chosen for the new super telescope. The ESO already has a considerable presence in the South American nation, so the…

Professor Lisa Harvey-Smith THE WONDERS OF RADIO ASTRONOMY Radio can unmask many hidden properties about the universe, including merging galaxies and Fast Radio Bursts. Professor Lisa Harvey-Smith speaks to All About Space about the mysterious majesty of the field Reported by Lee Cavendish What can be learnt from radio astronomy that isn’t revealed in other spectrums of light? Until about 400 years ago, we were, as human beings, completely blinkered. We didn’t have telescopes. We just had our own eyes and we just had the eyes that have evolved over millions of years of animal evolution on planet Earth. For that reason we can only see a tiny, narrow part of the spectrum. It was only much more recently that we started taking off the blinkers, certainly in the early…

Timeline of our planet’s fate Predictions are never easy, but what is the likely route to Earth’s demise? Present day An oasis for life Earth is the most fertile spot in the known universe, with a protective atmosphere and liquid water in abundance. Around 300,000 years Wolf-Rayet star WR 104 would have exploded, killing life on Earth Part of a binary star system 7,800 light years from Earth, WR 104 and its companion are expected to turn supernova within the next few hundred thousand years. Depending on WR 104’s axis of rotation, any resulting gamma ray burst could be aimed at Earth. 500,000 years Earth will be hit by an asteroid one kilometre (0.62 miles) wide Earth is hit by a large asteroid roughly once every 500,000 years, leading to…

The potential production and distribution of methane on Mars © T obias Roetsch Methane-stuffed crust Pockets of frozen methane could still exist from the planet’s formation and ancient evolution. As the unfiltered solar rays crack the surface, these pockets could release spikes of methane. Subsurface vents If Mars’ interior includes a liquid layer underneath the surface crust, then hydrothermal vents on the liquid layer’s floor could be spraying out methane. Miraculous microbes This could be key in finding alien life. As we know, life produces methane, and the only life that could exist on Mars is in the form of subsurface microbial life. Spraying from volcanoes If methane is produced under the surface, volcanoes could be the culprit behind its distribution. However, this is unlikely due to the planet’s current…

2 The Zooniverse Citizen science is a popular way to contribute to real science projects from the comfort of your own home. All you need is a laptop or computer with an internet connection and you can do some ‘real science’. The Zooniverse, found at zooniverse.org, is a world-famous organisation that contributes to hundreds of scientific projects and thrives on citizen science. If you want to help contribute by finding asteroids, exoplanets or even penguins, the Zooniverse is the place to be. © NASA/JPL-Caltech…

SENTINEL FAMILY © ESA; Getty The ESA’s Sentinels are designated to Earth observation, but each offers a unique function Sentinel-1 25 April 2016 Radar imager for land and ocean services. Sentinel-2 7 March 2017 Monitors vegetation, soil and water cover, inland waterways and coastal areas. Sentinel-3 16 February 2016 It measures sea-surface topography as well as surface temperature and colour. Sentinel-4 2023 Dedicated to monitoring atmospheric composition. Sentinel-5 2021 Also designed to measure atmospheric composition, but from a polar orbit. Sentinel-5P 13 October 2017 Measures the concentrations of trace gases, such as nitrogen dioxide, and aerosols in Earth’s atmosphere. Sentinel-6 2026 Intended to measure global sea-surface height using its radar altimeter for oceanography and climate studies.…

STARGAZER What’s in the sky? ESSENTIAL GUIDES AND ADVICE FOR AMATEUR ASTRONOMERS Jargon buster Conjunction A conjunction is an alignment of objects at the same celestial longitude. The conjunction of the Moon and the planets is determined with reference to the Sun. A planet is in conjunction with the Sun when it and Earth are aligned on opposite sides of the Sun. Right Ascension (RA) Right Ascension is to the sky what longitude is to the surface of the Earth, corresponding to east and west directions. It is measured in hours, minutes and seconds since, as the Earth rotates on its axis, we see different parts of the sky throughout the night. Declination (Dec) This tells you how high an object will rise in the sky. Like Earth’s latitude, Dec…

Solved: mystery of Venusian atmosphere’s weird rotation Words by Charles Q. Choi ©ISAS/JAXA The mystery behind why the atmosphere of Venus spins much faster than the planet’s surface may finally be solved. The finding might help shed light on how habitable distant exoplanets, worlds beyond our Solar System, may actually be. Compared to Earth’s 24-hour spin, Venus twirls at a leisurely pace on its axis, with its surface taking 243 Earth days to complete one rotation. However, the hot, deadly carbon-dioxide atmosphere of Venus spins nearly 60-times faster than its surface, whirling around the planet once every 96 hours in an effect known as super-rotation. Previous research suggests that in order for this super-rotation to occur the atmosphere of Venus has to possess enough angular momentum – the amount of…

Hubble image shows remains of ATLAS Words by Meghan Bartels Source: Wikipedia Commons © Martin Gembec Sky-watchers had high hopes that a comet called ATLAS would light up the night sky this spring, with forecasts suggesting it could become bright enough to see with the unaided eye. Instead the icy object crumbled to pieces – but it’s still putting on a spectacular show for scientists. Ye Quanzhi, an astronomer at the University of Maryland, snagged some time with NASA’s Hubble Space Telescope to take a look at Comet ATLAS on 20 April and caught a stunning image of its fragments that he shared on Twitter as a preview of his research. “We have been following the break-up of ATLAS since it was first detected in early April, but with ground-based…

Who’s involved in the ELT? United Kingdom The University of Oxford and the UK Astronomy Technology Centre are contributing to the HARMONI spectrograph. France France is involved in the design of the HARMONI, MAORY and METIS instruments. Spain Spain has made a number of contributions to the ELT, including the HARMONI spectrograph. Italy The Istituto Nazionale di Astrofisica is involved in the creation of the MAORY and MICADO instruments. Germany Germany’s contributions to the ELT include the MICADO and METIS instruments. The Netherlands Nederlandse Onderzoekschool Voor Astronomie has been involved in the creation of the METIS and MICADO elements of the ground-based telescope. Belgium Belgium’s Katholieke Universiteit Leuven has been working on the METIS spectrograph instrument. Switzerland ETH Zürich has worked on the ELT’s METIS instrument. Austria The ELT’s MICADO…

How can we… …avoid an asteroid impact The Minor Planet Center in Cambridge, Massachusetts, has been cataloguing asteroid and comet orbits for over 70 years. Proposed strategies involve breaking up asteroids so they burn up harmlessly in the atmosphere or delaying arrival times so they miss Earth. …escape an expanding red giant Sun If we could push Earth just a little bit further out from the Sun – say, an additional 15 per cent – it’s been suggested that it would definitely survive the furthest reach of the Sun’s expansion into a red giant, although it still wouldn’t be a viable place on which to grow crops. …avoid a runaway greenhouse effect In the long term, this looks unavoidable. Once the Sun’s luminosity overtakes Earth’s ability to dissipate absorbed radiation…

Where does it all end? Cosmologists have put forward several different scenarios for where our universe ends The universe goes on forever The universe could be infinite in extent, endlessly continuing in all directions, on and on beyond our cosmic horizon with no edges or boundaries. If this picture is accurate then the universe has no edge, and it gives rise to the idea that eventually the same configuration of atoms would repeat in the universe. This means that there is another Earth and another you out there somewhere in the universe right now. Other universes If cosmic inflation really happened – the super-rapid expansion of our universe in its earliest moments – then it may have happened more than once, giving rise to neighbouring universes. According to Albanian-American cosmologist…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE Hubble’s 30th birthday photo To celebrate three decades of top-class cosmic observations, the NASA/ESA’s Hubble Space Telescope has once again delivered with a spectacular sight of the universe: the energetic bursts of star formation within the Milky Way’s neighbouring dwarf galaxy, the Large Magellanic Cloud. The larger magnificent centrepiece of this snap is known as NGC 2014 and is lit up by young stars ionising the hydrogen in the surrounding gas, giving it an orange-red hue. The nebula’s smaller companion is NGC 2020, coloured blue due to energised oxygen atoms. It’s not too difficult to see why the pairing has been given the nickname of the ‘Cosmic Reef’. © NASA/ESA Painting or photograph? The vibrant blend and flow of colours on display…

Our Solar System stole asteroids from interstellar space A cache of interstellar asteroids may have been hiding under scientists’ noses for billions of years according to new research focused on a handful of strange space rocks known as Centaurs, which orbit the Sun in the neighbourhood of Jupiter and Saturn. Centaurs’ orbits are very unpredictable, with simulations suggesting that they should bang into things or fly out of the Solar System. The new research suggests that’s because they were stolen by our Solar System when it was very young. With so much less expansion under the universe’s belt, stars were closer. “The close proximity of the stars meant that they felt each others’ gravity much more strongly in those early days than they do today,” said Fathi Namouni, an astronomer…

Rise of the super telescope Building a towering telescope From its giant mirrors to its state-of-the-art instruments, the ELT is set to be a marvel of modern engineering 1 Primary mirror The 39.3-metre (128.9-foot) primary mirror is made up of individual hexagonal segments and collects light from the sky. It reflects all of that light back towards the secondary mirror. 2 Secondary mirror At 4.2 metres (13.8 feet), the secondary mirror is designed to support the light-gathering power of the main mirror. It will reflect light towards the third mirror in the process. 3 Third mirror The third mirror in the five-mirror ELT set-up collects the light bounced from the primary and secondary mirrors and delivers it towards an adaptive flat mirror positioned above it. 4…

Jupiter THERE’S MORE WATER ON JUPITER THAN FIRST THOUGHT Observations from the Jovian king’s companion spacecraft have turned up an astounding result Reported by Elizabeth Howell © NASA/JPL-Caltech Newly released data from NASA’s Juno probe shows that water may make up about 0.25 per cent of the molecules in the atmosphere over Jupiter’s equator. While that doesn’t sound like much, the calculation is based on a prevalence of water’s components, hydrogen and oxygen, three times more than at the Sun. The new measurements Juno obtained are much higher than a previous mission suggested. The surprise result has scientists delving deep into results from NASA’s Galileo mission to Jupiter, which obtained drier results in 1995 when engineers deliberately threw the spacecraft into Jupiter’s atmosphere. Galileo was low on fuel and NASA…

The last days of Earth THE LAST DAYS OF EARTH In the grand cosmic scale of the universe, our planet is doomed. All About Space explores what will occur during Earth’s final moments Reported by Paul Cockburn © Tobias Roetsch Apollo 17 may have been the 20th century’s final crewed mission beyond Earth orbit, but its crew left us with one very public legacy – the iconic ‘Blue Marble’ image of planet Earth, which during the last 48 years has become one of the most reproduced images in human history. Admittedly that’s barely a pinprick when compared to the history of life on Earth as a whole: when you consider that the first ‘living’ molecules appeared some 3.8 billion years ago – and that by current estimates the last are…

Future tech Floating colonies on Venus FLOATING COLONIES ON VENUS High above the carbon-dioxide-laden clouds, this planet could turn from hostile to relatively hospitable for future astronauts © Adrian Mann It’s incredibly hot, with a searing average temperature of over 460 degrees Celsius (860 degrees Fahrenheit). Its atmosphere is thick with choking carbon dioxide, laced with poisonous sulphuric-acid clouds that hang above a parched desert-like landscape, renewed by the angry eruptions of volcanoes. Without a doubt Venus – with its additional high-pressure environment that has a crushing power almost 100 times that of Earth’s – is unfriendly for life. Sending astronauts to a world that can cook, crush and choke in just a few seconds and hoping they survive is ambitious to say the least. However, according to some –…

The size of the universe The observable cosmos is not the whole story when astronomers consider how big the universe really is © Nicholas Forder The cosmic microwave background (CMB) is the furthest that astronomers are able to see from Earth. This ancient light was released when the universe was approximately 380,000 years old, and has been travelling across the cosmos ever since. The furthest galaxies we can see are almost as far away as the CMB – some 13.8 billion light years away. At least that is where they were when the light originally set off. While their light has been making its way to Earth, the universe has carried that part of space ever further from us. That point is now around 45 billion light years away, in…

What happened to Schiaparelli? Schiaparelli separates 16 October 2016 / 14:42:00 After a seven-month voyage through the Solar System the first instalment of the ExoMars package arrived at Mars. This started the separation of the orbiter and Schiaparelli. © ESA Wake from hibernation 19 October 2016 / 13:29:48 Spacecraft tend to hibernate during their voyage in order to save power and maintain software. The ExoMars team awoke Schiaparelli after a further three-day journey. © ESA Feel of the atmosphere 19 October 2016 / 14:42:22 The entry, descent and landing demonstrator module’s accelerometers first felt the touch of Mars’ atmosphere just over an hour after waking up from hibernation. © ESA Data glitch 19 October 2016 / 14:45:23 Much of the time spent trying to slow the lander down went relatively…

Impact of COVID-19 SPACE, SATELLITES AND SELF-ISOLATION THE ASTRONOMICAL IMPACT OF COVID-19 Coronavirus has had seismic effects on all aspects of life globally, but what has the space industry been able to tell us, and what can it do to help? Reported by Lee Cavendish © Getty © NASA The world is in the midst of an unprecedented pandemic, and it is having a profound effect on individuals, businesses and industries across the globe. Since COVID-19 – also known as ‘coronavirus’ – gained global attention at the beginning of 2020, it has had a knock-on effect that can even be seen from space. In response to battling the virus, almost all the world’s governments have issued strict lockdown policies stating that people can only leave their homes for essential shopping…

ASK Space Our experts answer your questions EXOPLANETS © NASA/JPL-Caltech Headshot © Seth Shostak/SETI Institute What do we know about Kepler-452b’s surface? We know very little about what the planet is like. We know that the star is essentially the same temperature as the Sun, about 5,500 degrees Celsius (9,900 degrees Fahrenheit), and is just a little bit bigger than the Sun. Its estimated age is 6 billion years old, so it’s about 2 billion years older than our own star. We know that this planet is about five per cent farther from its star than our planet is from the Sun. That’s what makes it very interesting: it’s the closest analogue we have to the Sun-Earth system outside our own Solar System. In terms of the surface of the…

Moon tour Tycho Find one of the most famous craters on the lunar surface; the star of one of the most famous science-fiction films ever made © NASA Like the craters Copernicus and Plato, and other features such as the Apennine Mountains and Sinus Iridum, Tycho is a true lunar celebrity. Named after the famous Danish astronomer Tycho Brahe, a larger-than-life character best known for wearing a gold nose after his own was cut off in a duel, it has an even greater claim to fame: it featured in the classic 1960s sci-fi film 2001: A Space Odyssey. Unlike some lunar features, finding Tycho is almost embarrassingly easy. If you look down towards the bottom of the lunar disc when the Moon is full, around 4 June, rising mid-evening in…