Sommaire pour No. 101 de All About Space

Welcome © Getty The star of the month this issue – and let's be honest, it has been for the past few weeks – is red supergiant Betelgeuse. If you've been following the latest on the swollen member of the constellation Orion or have even observed it yourself, then you'll know that its weird dimming and brightening over a long period of time has got astronomers talking. So why the fuss? It's taken over 150 years of observations for something notable to happen, earmarking it as the next supernova candidate. Understandably, astronomers – whether they're professional or amateur – are waiting for the inevitable to happen, and while they're hoping for the sky to be lit up by the equivalent of 10,000 Suns, they reveal to All About Space the…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE Photons could uncover ‘massive gravity’, brand new theory suggests Words by Rafi Letzter © Getty Gravitational waves, ripples in space-time, slip through Earth all the time, carrying secrets about the universe. Until a few years ago we couldn’t detect these at all, and even now we have only a basic ability to detect the stretching and squeezing of the cosmos. A proposed new gravitational-wave hunter, which would measure how particles of light and gravity interact, could change that. In the process it could answer big questions about dark energy and the universe’s expansion. The detectors on Earth today, called the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo, operate according to the same principle: as a gravitational wave moves through the Earth, it…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE NASA’s solar probe spots ‘stealth’ outburst on the Sun ©NASA Coronal mass ejections (CMEs) aren’t known for being subtle: each event can fling huge amounts of the soup of charged particles called plasma off the Sun and out into the Solar System. In November 2018, as seen from Earth and certain spacecraft, the Sun seemed to be calm… but it wasn’t. It was experiencing what scientists call a ‘stealth’ coronal mass ejection. Conveniently, NASA’s Parker Solar Probe was completing its first close pass behind the Sun at the time, putting its instruments in a perfect position to see what was happening on 11 and 12 November during this usually cryptic event. “If you’ve ever seen a CME image, you normally see a…

THE NEXT SUPERNOVA? We’re overdue a spectacular display of stellar fireworks, so where will it come from? Reported by James Romero In the near future, the full Moon will have a luminous rival as a cataclysmic event 650 light years away will momentarily shine with the brightness of 10 billion Suns. The aftereffects will hang in our sky for many months, and permanently alter our night sky in a way not witnessed in recent human history. Betelgeuse is one of our most recognisable stars. Forming part of the Orion constellation, its bright-red appearance, due to its vast size, has been noted by stargazers since antiquity. Place Betelgeuse in the exact location of our Sun and the star’s equator would extend out to the orbit of Jupiter, with all the inner…

HOW BETELGEUSE’S SUPERNOVA WILL LOOK FROM EARTH Getting brighter Between now and 100,000 years’ time Astronomers will know Betelgeuse has exploded before we see it. The light of the explosion will be slowed down as it passes through gas surrounding the dying star. Ghostly particles called neutrinos will pass straight through and beat the light here. At its brightest First week of brightening Betelgeuse will take time to ramp up to maximum brightness – this usually takes about a week or two. Astronomers can estimate this by looking at how the light from other similar supernovae varies in the days and weeks after denotation. Fading away A few months after peak brightness The light curves from other Type II supernovae show that the fading process happens in two stages. First…

The four sampling sites on Bennu These sites, named after birds native to Egypt, were the four candidates singled out to be visited by OSIRIS-REx. But there can only be one… © NASA Sandpiper Latitude: -47 degrees Longitude: 322 degrees The southernmost site is a flat piece of land on the wall of a large crater, but appears to have hydrated minerals. This could have revealed promising details about unmodified water-rich materials. Nightingale Latitude: 56 degrees Longitude: 43 degrees This was chosen as the site that will be kissed by OSIRIS-REx’s TAGSAM arm in July 2020. The fact it is near the north pole means this region has stayed cool for millions of years. Osprey Latitude: 11 degrees Longitude: 88 degrees The other site near the equator was also considered…

G objects MYSTERIES OF THE UNIVERSE WHAT’S ORBITING OUR GALAXY’S BLACK HOLE? Six strange objects have been found in the vicinity of Sagittarius A* – and there may be more Reported by David Crookes © Tobias Roetsch At the heart of the Milky Way is a supermassive black hole called Sagittarius A*. We know it is 26,000 light years from Earth and that it has 4 million times the mass of the Sun. We also found out last year that it is surrounded by a cool gas halo and is perhaps quieter than its counterparts in other galaxies because of magnetic fields. What we’re less certain about, however, is the make-up of six strange objects that have been discovered relatively close by. Found to orbit Sagittarius A*, or Sgr A*…

Mercury WHAT’S NEW AT MERCURY? Scientists are still busy analysing data from the MESSENGER mission – and it has plenty of surprises Reported by Andrew May © Getty © NASA Which planet is Earth’s nearest neighbour in the Solar System? The obvious answer is Venus, which makes the closest approach to us – but it spends half its orbit on the other side of the Sun, when it’s further away from us than Mercury. It was only last year that Tom Stockman, a graduate research assistant at Los Alamos National Laboratory, New Mexico, and colleagues crunched the numbers to work out which planet is actually closest on average – and they were as surprised as anyone by the answer: “When averaged over time, Earth’s nearest neighbour is in fact Mercury,”…

THE CHANGING CLIMATE OF VENUS According to research, our neighbour’s environment has changed dramatically © NASA STEP 1 Magma ocean Just like the primitive Earth, early Venus was still largely molten as a result of the high-energy impacts that formed the planet in the first place. This led to a widespread ocean of magma (molten rock) across the planet, leading to very high temperatures. STEP 2 Gas and steam Impacts added additional material to Venus, including a significant amount of water. Coupled with the heat from the magma ocean and Venus’ proximity to the Sun, an early atmosphere began to form around the planet, largely made of carbon dioxide and steam. STEP 3 Cooling and condensing Over time the number of impacts began to die away; the unbattered planet began…

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…

MISSION PROFILE OSIRIS-REx NASA’s asteroid explorer has been at Bennu for over a year now, but the best part is yet to come Mission type Sample return Operator NASA Launch date 8 September 2016 Target 101955 Bennu Arrival at target 3 December 2018 Primary objective Survey and collect a sample from a carbon-rich near-Earth asteroid Status Operational OSIRIS-REx is the third part of NASA’s New Frontiers Program, succeeding the likes of New Horizons and Juno. All three are completely reshaping our understanding of the Solar System, and OSIRIS-REx is doing so at the asteroid 101955 Bennu. The Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRISREx) spacecraft was launched with a game plan to break records and do something that hasn’t been done since the Apollo era. “It’s a mission…

Animal milestones Number of notable creatures launched into space Figures are calculated based on best available information Fruit Flies 20 February 1947 The first animals in space were fruit flies launched on a captured Nazi V-2 rocket to a height of 109 kilometres (68 miles). Ham 31 January 1961 Ham the chimp was the first hominid to be sent into space. He proved organisms could operate successfully in microgravity. Chickens 13 March 1989 On STS-29, 32 chicken embryos were taken to space, with a handful managing to hatch successfully. Albert II 14 June 1949 The first monkey in space was the American Albert II, launching to a height of 134 kilometres (83 miles). Arabella and Anita 28 July 1973 These two spiders demonstrated that they could spin webs even in…

ASK Space Our experts answer your questions SOLAR SYSTEM How does organic material on Enceladus compare to that found on Mars? © Tobias Roetsch The most intriguing difference is how easily one finds complex organics on Saturn’s moon Enceladus compared to Mars. If you consider the enormous efforts put into the search for organics on Mars since the 1970s without success, it is just amazing how easily we found complex and diverse organic chemistry on Enceladus just with a spacecraft flying by. However, it is a huge success that NASA’s Curiosity finally found organics on Mars. From what I read the organics on Mars – like the Enceladean ones – could be large molecules that contain aromatic and aliphatic structures. Whereas we find oxygen and probably nitrogen in both organic…

Deep sky challenge Intriguing galaxies and sparkling clusters Spring is finally here, so now’s the time to go hunting in Coma Berenices and Canes Venatici © NASA;ESA As winter turns to spring the very nature of the night sky changes. Gone are winter’s bright stars, bold constellations and obvious deep-sky delights such as the Orion Nebula, the Pleiades and open cluster M35. Replacing them are subtler constellations drawn with dimmer, less-obvious stars, and a host of deep-sky objects that are as distant as they are faint. Apart from the beautiful globular cluster M53, which is always worth a look on a clear night, this month’s challenges are galaxies dozens of light years from Earth. They lie in two of the most overlooked constellations – Canes Venatici and Coma Berenices. All…

Astroshots of the month Send your astrophotography images to space@spaceanswers.com for a chance to see them featured in All About Space Jeff Johnson Las Cruces, New Mexico Telescope: Takahashi TOA-130F refractor “I have a long love of astronomy and have observed the night sky for many years with binoculars and a telescope from the age of ten. I did my first ‘real’ astrophotography in 1996 when I used a 35mm SLR camera to take photos of Comet Hyakutake. I took a tripod out into the desert here in Las Cruces and just experimented with exposures. Later I bought a 10” Dobsonian for viewing, and within a week was taking pictures through the eyepiece for fun. Within a few more weeks, I knew I wanted to get serious with astroimaging.” Patrick…

STARGAZER Olivon T800 With its sturdy outer armour combined with nitrogen gas-filled optics, this spotting scope is ideal for observing while staying protected from dew The spotting scope is an instrument that’s not very well associated with stargazing – it is most commonly used by the avid nature watcher who takes great delight in observing birds and other forms of wildlife. Given our experience with the T800 though, we found it to be an ideal companion for observing the night sky, in particular the Moon and notable star clusters, including the fine globular cluster Messier 7 in the constellation of Scorpius, close to the ‘stinger’ of the Scorpion. Taking the spotting scope out of its box, we admired the care that had been put into packaging it: the box is…

In the shops The latest books, apps, software, tech and accessories for space and astronomy fans alike Book 50 Things to See in the Sky Cost: £9.99 (approx. $12.97) From: Penguin Random House A beautifully presented, practical guide to 50 sights in the skies above us complete with a glow-in-the dark front cover. Explained with fascinating, easy-to-understand commentary from astrophysicist and science communicator Sarah Barker and illustrated throughout with captivating drawings by Maria Nilsson, each guide helps you locate an incredible sight. The book is divided into three main sections, and whether you use the naked eye, a telescope or fall into a black hole of online research, you’ll discover the limitless wonder of the skies, from otherworldly phenomena on Earth like Sun dogs to planets, moons, stars, lunar…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE Our Sun, as you’ve never seen it before © NSO/AURA/NSF The world’s largest solar telescope is still in the process of having its full instrumental suite assembled, but the first piece of aparatus that was set up has shown the world a glimpse of its incredible power. The National Solar Observatory’s four-metre (13-foot) Daniel K. Inouye Solar Telescope has revealed to the world the most detailed image of the Sun’s surface to date. This telescope, which sits on the summit of Haleakalā, Hawaii, as part of Haleakalā Observatory, will continue to revolutionise the investigation of our nearest star, and this is just the start of what they hope will be a 50-year investigation. To put this image into perspective, each cell-like structure…

A single grain of Apollo Moon dust opens up a world of lunar science A team of scientists set out to find a way to analyse Moon dust based on only a single grain of the material. The researchers reported their results in a new study that analyses a single grain of Moon dust gathered in 1972 by astronauts on the Apollo 17 mission. “We’re analysing rocks from space, atom by atom,” revealed Jennika Greer, a doctoral student in geophysical sciences at the University of Chicago. “It’s the first time a lunar sample has been studied like this. We’re using a technique many geologists haven’t even heard of.” “We can apply this technique to samples no one has studied,” Philipp Heck, a curator at the Field Museum, said. “You’re almost…

The next supernova THE VERA RUBIN OBSERVATORY Source: Wikipedia © LSST Project/J. Andrew © LSST Project Under construction atop Chile’s Cerro Pachón, the Vera C. Rubin Observatory, formerly the Large Synoptic Survey Telescope, will survey a huge area of the Southern Hemisphere sky, providing data for a wide range of scientific objectives. For supernova scientists the value of the VRO comes down to its ability to image the entire sky repeatedly every few nights, and to great depth. This means it could spot hundreds of thousands of new events. Within a minute of each change in the sky, the VRO will alert the community to respond, catching supernovae events before they fade forever. 1 Panning a large mirror The VRO’s reflecting telescope contains an 8.4-metre (28-foot) primary mirror that…

BETELGEUSE VS THE SOLAR SYSTEM © Getty Betelgeuse is expected to have an absolute magnitude of -16 or -17 when it blows up. When you calculate how far away it is, this would make it as bright as the full Moon. In its current red supergiant phase Betelgeuse has a diameter of just over a billion kilometres, which is 900 times that of our Sun. Betelgeuse is so large that if we place it in the Sun’s exact spot in our Solar System, all the rocky inner planets – and perhaps even Jupiter – would be orbiting inside its atmosphere.…

HOW ARE THE G OBJECTS BEHAVING? The G objects are understood to be in class of their own © Tobias Roetsch © JAnna Ciurlo, Tuan Do/UCLA Galactic Center Group Different orbits The objects G1 and G2 follow a similar orbit around the black hole, but G3 to G6 take very different paths that can take anywhere between 170 and 1,600 years to complete. Central star Given that the G objects are not destroyed when they get close to the black hole, a recent study has suggested a stellar-sized mass is at the centre of each one. Distance from the black hole Each of the G objects are within 0.04 parsecs of the black hole, which means they are close, but still far from the event horizon. Gas and dust Under…

Future tech Clear Space-1 CLEARSPACE-1 THE KAMIKAZE SPACE CLEANER This European mission will be purging low-Earth orbit with a space-debris removal plan for 2025 © Adrian Mann Constant threat of space debris With over 3,000 obsolete satellites, there are risks of collisions that will cause even more space debris to fire off in every direction at high speeds. Perish in the atmosphere By dragging the space debris into the atmosphere, the temperatures created by reentry will disintegrate it, thus removing the problem. The chaser The ‘chaser’ is ClearSpace-1’s four-armed robot that is tasked with catching space debris and dragging it back to Earth. The key is reusability ClearSpace CEO Luc Piguet has stated that it wants to create a product that can be replicated and reused. Vespa This particular piece…

INTERVIEW BIO Professor David Rothery Rothery became a professor of planetary sciences at the Open University, Milton Keynes, UK, in November 2013. He specialises in general geology, planetary sciences and volcanism. In 2006 he was named the UK principal investigator for the Mercury Imaging X-ray Spectrometer (MIXS) instrument aboard the European Space Agency (ESA)/Japan Aerospace Exploration Agency (JAXA) BepiColombo mission to Mercury. He also chairs the ESA’s Mercury Surface and Composition Working Group.…

Gravitational waves GRAVITATIONAL WAVES HIT EARTH ...and astronomers don’t have a clue on where in the universe it came from Reported by Yasemin Saplakoglu © Mark Garlick/Science Photo Library A mysterious cosmic event might have ever so slightly stretched and squeezed our planet. On 14 January astronomers detected a split-second burst of gravitational waves, distortions in space-time – but researchers don’t know where this burst came from. The signal, picked up by the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometer, lasted only 14 milliseconds, and astronomers haven’t yet been able to pinpoint the burst’s cause or determine whether it was just a blip in the detectors. Gravitational waves can be caused by the collision of massive objects, such as two black holes or two neutron stars. Astronomers detected…

Starlink SPACEX’S STARLINK CATCH ASTRONOMERS OFF GUARD The satellites launched so far are much more visible than expected © Getty © SpaceX; Getty SpaceX founder and CEO Elon Musk announced the Starlink concept back in January 2015, explaining the company intended to launch about 4,000 broadband satellites into low-Earth orbit to provide low-cost internet to people around the world. The envisioned numbers have grown since then. SpaceX now has permission from the US Federal Communications Commission to loft about 12,000 Starlink craft, and the company has applied to an international radio-frequency regulator for approval of up to 30,000 additional satellites. For perspective, there are only about 2,000 operational satellites in orbit today, and humanity has launched only around 9,000 craft into space in all of history. Shortly after deployment, the…

Moon tour Herschel Explore a crater near the Moon’s centre, named after an important astronomer © NASA The Herschels probably discovered, observed and recorded more planets, moons, comets and other objects than any other family, and today their achievements are rightly honoured on worlds and satellites across the Solar System, with craters that bear their family or individual name. Our Moon Tour destination this month is one of those craters – a small crater named after William Herschel, brother of Caroline and father of John. When seasoned lunar observers try to help newcomers locate a feature on the Moon, they usually describe it in relation to its position either within a circle or around a clock face. Mare Crisium is well known as the ’dark patch to the top right…