Sommaire pour No. 90 de All About Space

Welcome If you hadn't noticed already, All About Space is an impressive 90 issues old – to celebrate the occasion we've teamed up with HarperCollins to give you a free copy of the 2019 Guide to the Night Sky, packed with tips, tricks and advice on what to observe and when throughout the following months of the year. Written and illustrated by astronomers Storm Dunlop and Wil Tirion, it's the perfect guide for all levels of astronomer – from those just making their first tentative steps into exploring the heavens to those who are veterans of sky-watching and just need that quick reference. Our space myths busted series continues this month as astronomers reveal what likely caused a sonic boom, tipped to be some six-times 'louder' than expected, to tear…

‘The Banded Marble’ © NASA/JPL-Caltech Many have described Earth as ‘The Blue Marble’ since the famous Apollo 17 image, but perhaps it’s time to call Jupiter ‘The Banded Marble’, as this Juno image seems to suggest. Taken during a flyby on the 12 February 2019, the shot was edited by citizen scientist Kevin M. Gill. The images taken by Juno’s JunoCam have been emphasised to bring out the finer details of Jupiter, in particular the bands of storms and winds that are crashing into each other over the face of the gas giant. The Great Red Spot also makes an appearance in the top-right section of the image.…

The Sun’s equinox © ESA/NASA/SOHO 20 March marked the annual spring equinox, marking the beginning of warmer seasons in the Northern Hemisphere. The recent change in events also saw the ESA/NASA Solar and Heliospheric Observatory (SOHO) capture the Sun in different wavebands. From left to right, SOHO observed the Sun in 171 angstroms, 195 angstroms, 284 angstroms and 304 angstroms wavelengths respectively, which all correspond to different parts of the ultraviolet section of the electromagnetic spectrum.…

Bennu’s rockier than expected NASA’s Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) spacecraft has now been at the asteroid Bennu for months, trying to learn its secrets. One of the things learned was just how bumpy the surface actually is. The mission team were expecting a rugged surface, but Bennu shows a flurry of boulders and rocks all over, as revealed in the asteroid’s southern hemisphere. This has caused the team to re-evaluate the area in which they will collect an asteroid sample.…

Ready for the Red Planet: NASA's Mars Helicopter aces key flight tests © NASA/JPL-Caltech ; Gabriel Perez Diaz/Instituto de Astrofisica de Canarias; NASA's Mars Helicopter has proven its off-world mettle. The technology demonstrator, which will launch with NASA's next Mars rover in July 2020, aced its first-ever test flight under Red Planet conditions, agency officials have announced. "Gearing up for that first flight on Mars, we have logged over 75 minutes of flying time with an engineering model, which was a close approximation of our helicopter," Mars Helicopter project manager MiMi Aung of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, said in a statement. "But this recent test of the flight model was the real deal," she added. "This is our helicopter bound for Mars. We needed to see…

Sound comparisons in the universe Listen up: space could be a noisy place if it was full of air Space roar Six-times intensity of any source measured The space roar has been found to be much louder than most parts of the universe. The Sun 290 decibels If we could hear the Sun, we'd all be wearing earmuffs. Even from Earth the Sun would be 125 decibels. Saturn V rocket 204 decibels If you were standing too close when a rocket launched, the constant sound would seriously hurt your ears. A big caldera 172 decibels Krakatau made an incredible sound when it erupted on 27 August 1883; it was heard 100 miles away. ISS 78 decibels ISS astronauts used to wear earplugs all day, but NASA worked on lowering noise…

What it’s thought to be Numerous theories about the space roar have been raised The earliest stars ARCADE was designed to detect the faintest signs of heat from the first generation of stars, so do these account for the noise? It's unlikely since it was six-times louder than expected – far greater than what those stars should be emitting. A bubble around the Sun It’s possible that there is a small bubble around the Sun. As scientist Dale J. Fixsen tells us, it wouldn't have to be very bright since it is so close to us, thereby appearing normal. Dim radio galaxies packed together There is one major problem with the theory that the source is radio galaxies very close together: those galaxies would have to be so packed that…

Key to life Water and organics: exoplanet families The simple chemistry of H2O and organic molecules makes them ubiquitous in gas, liquid and ice across the Solar System and cosmos Water WASP-39b This ‘hot Saturn’ contains large quantities of water in its atmosphere, possibly from its formation further out. Europa Jupiter’s moon has a water-ice surface. However, it is the deep ocean we think lies beneath that excites astrobiologists most. Triton Recent modelling suggests that tidal heating from Neptune could help maintain a subsurface ‘liquid layer’ under its water-ice crust. Gliese 1214 b Discovered in 2009, this super-Earth has been dubbed ‘the waterworld’ and is the most likely ocean exoplanet candidate. HD 21749b A sub-Neptune exoplanet too dense to be a gas giant, but not dense enough to be rocky.…

Focus on 'WEIGHING' THE MILKY WAY Astronomers have managed to measure the mass of our home galaxy in unprecedented detail, potentially solving some cosmological riddles Reported by Lee Cavendish © ESA/Gaia The Milky Way is comprised of gas, dust, planets, stars, black holes and, of course, the ever-elusive dark matter. For decades astronomers have been trying to pin down the mass of our home galaxy to a good degree of accuracy, with past results varying from 500 billion-times the mass of our Sun – also known as a solar mass – to 3 trillion solar masses. This variation comes down to the difficulty in measuring the amount of dark matter that resides in our galactic home. Recently, two heavyweights in the space observatory industry teamed up to take on the…

Instant Expert Retrograde motion explained Our expert explains why some celestial objects appear to take the unusual route of travelling backwards in the night sky 1. Before the backwards motion As Mars travels on its orbit, wider compared to Earth’s, it moves from east to west in the night sky, similarly to the rest of the stars. 2. Earth begins to undertake Mars When Earth begins to undertake Mars in its closer orbit after a few months, its movement in the night sky begins to reverse relative to the other stars. This is the start of its ‘retrograde motion’ and can only be seen by observing planets in the Solar System. 3. After months of Mars moving slower After a couple more months Mars has undoubtedly gone back on itself…

STARGAZER This month’s planets The God of War rules the night this May, while the King of the Solar System has a long reign in the sky Planet of the month Constellation: Taurus Magnitude: 1.6 AM/PM: PM Mars might not be the brightest planet in the sky this month – shining at magnitude 1.6 it will only be as bright as Castor in Gemini, which itself is only the 20th-brightest star in the whole sky – but there is so much going on around it. Between late-April and late-May Mars will be a modestly bright ‘Evening Star’ low in the western sky after sunset, looking like an extra orange ‘star’ between the horns of Taurus, The Bull, to the upper left of the Hyades and Pleiades star clusters. That’s quite…

STARGAZER How to… Photograph the Moon in May May will be a great month for anyone who wants to get started in astrophotography - because our natural satellite will be a very tempting target on several evenings… © Dietmar Rabich You’ll need: ✓ DSLR (Digital Single Lens Reflex) camera ✓ Sturdy tripod ✓ Cable release ✓ Wide-angle lens (35mm focal length or shorter) ✓ Zoom or telephoto lens (200mm or longer) ✓ Computer ✓ Image-processing software Open up any copy of All About Space and you’ll see lots of beautiful images of the night sky – astrophotographs, pictures of astronomical events and celestial objects taken by amateur astronomers. Many are the result of many hours of hard work processing images taken with very sophisticated – and very expensive –…

Astronomers spot a space butterfly © NASA/JPL-Caltech Butterflies are seen flittering all around the world in their majesty, but it’s rare to find one in the cosmos. NASA’s Spitzer Space Telescope recently used its infrared capabilities to spot a ‘space butterfly’ in the wilds of the night sky. Officially labelled as Westerhout 40 (W40), this is obviously a nebula – a cloud of gas and dust that is illuminated red by the new stars that are being born within. The ‘wings’ in this image are hot, interstellar gas blown away by the radiation of the most massive stellar objects within the active region.…

The mystery of the brain terrain ©NASA/JPL-Caltech/University of Arizona NASA’s Mars Reconnaissance Orbiter (MRO) has done a phenomenal job of photographing Mars’ surface. Here it captured the ‘brain terrain’ in the Protonilus Mensae. This terrain is a mystery for astronomers as they can’t seem to explain how it came about. It’s thought that beneath the rugged surface lies water ice, and when it sublimates – converts from solid to gas – it creates frozen troughs. This could be an ongoing active process, but MRO’s HiRISE camera has yet to observe any changes to the environment.…

FUTURE TECH ORBEX’S PRIME ROCKET Satellites will soon launch from Scotland, as revealed by a UK-based company with an exciting new prototype Reported by Lee Cavendish © Orbex Orbex, a UK-based spaceflight company, is making amazing headway in bringing satellite launches to the Scottish Highlands with the unveiling of its exciting two-stage rocket. At a private event on 7 February 2019, Orbex flaunted a prototype of the Stage 2 Prime rocket for the first time, announcing that it will be lighter, more efficient, better for the environment and will include the world’s first 3D-printed rocket engine. Orbex has only come into the public eye relatively recently; in July 2018 the UK Space Agency chose Orbex to launch from its spaceport in Sutherland, Scotland. From there it has gained amazing support…

Apollo 7: the mutiny The crew didn't want to follow certain orders from NASA Walter M. Schirra Walter M. Schirra was the commander of Apollo 7: the first of the Apollo missions to carry a human crew into space. About 15 hours into the flight he got a cold, felt bad and asked that a live TV broadcast be delayed to allow mission tests to be completed. “We do not have the equipment out; we have not had an opportunity to follow setting; we have not eaten at this point,” he snapped at Mission Control, thereby disobeying the request for a camera to be turned on. What was the penalty? Unknown, but Schirra was already set to retire from NASA and had announced his intention. Donn F. Eisele Schirra's irritability…

Apollo 10 APOLLO 10 Preparing for history Apollo 10 headed for the Moon with arguably more risk, but did not make the cut for a lunar touchdown Reported by Lee Cavendish © NASA; SpoonGraphics Issue 88 of All About Space told the story of Apollo 9 as it saw its 50th anniversary. Just a few months after the Apollo 9 mission, on 18 May 1969, was the launch of Apollo 10. This mission saw three of NASA’s finest perform the ‘rehearsal’ for the Apollo 11 mission – they left Earth, went to the Moon and made a Lunar Module descent, but didn't actually make the historic touchdown. The Apollo 10 mission put everything into place so that Apollo 11 could live on in history books. The trio of cosmic adventurers…

Moon tour Kepler Take a look at one of the most striking small craters on the lunar surface © NASA Look at the full Moon through your binoculars or small telescope and once your dazzled eyes have stopped watering you will see a triangle of small, bright dots on the left-hand side of the almost blindingly bright disc, just above its centre, looking for all the world like the bright mark a trio of stones made when smashed into the ice covering a frozen pond or lake. These bright spots are craters: three of the most famous and widely observed craters on the whole of the Moon. The one in the centre is called Kepler, and it’s our destination for this month’s tour… Kepler is a reasonably small crater. It…

Photograph the Moon in May Getting the perfect shot Keep adjusting settings until you are happy with your images When you take your photographs, bracket the exposures – take exposures of long and short duration – until you find one which works, then stick with that. Try combinations of different exposures, apertures and ISOs until you have taken an image you like, then stick with that combination and take more. The main thing is to simply experiment – and have fun! 1 Get the timing right On 7 May a very thin crescent Moon will be close to Mars. Use both your lenses to capture lovely views of the pair shining close together in the dusk. 2 Wait for Earthshine On 8 May use your long lens to capture the…

Deep sky challenge Hunting for faint fuzzies around the Great Bear With the Big Dipper hanging overhead, spring nights are perfect for exploring the hidden treasures of Ursa Major Think of Ursa Major and you probably think of the seven bright naked-eye stars that make up the famous asterism ‘The Big Dipper’, including the best known double star in the sky – Mizar – and the twin ‘Pointers’ that point the way to Polaris, The Pole Star, in neighbouring Ursa Minor. But this northern constellation – high overhead as darkness falls on these spring nights – has a lot more to offer. Lurking inside the boundaries of Ursa Major are many deep-sky objects unfamiliar to and unobserved by many telescope owners. There are plenty of galaxies for observers who like…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE The rains down in Africa © Copernicus Sentinel data (2019)/ESA Millions of people residing in Mozambique, Malawi and Zimbabwe experienced what was tipped to be the worst storm the Southern Hemisphere has seen so far this year: Cyclone Idai. Copernicus Sentinel-1 captured the flooding – shown in red – in the port town of Beira in Mozambique. This imagery will assist aid relief efforts by showing the areas most affected by the storm.…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE Oil spill seen from space © Copernicus Sentinel data (2019)/ESA/ It’s sad to see the Earth suffer the consequences of human negligence. Here, the ESA’s Copernicus Sentinel-1 satellite spys a 2,200-tonne oil spill from the Grande America vessel. On 12 March 2019, the Italian container ship was just 300 kilometres (190 miles) off the French coast when the vessel caught fire and sank in the Atlantic Ocean. The Copernicus Sentinel-1 satellite has captured images of the huge, black stretch of oil spread out over 50 kilometres (30 miles).…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE Starquakes rock alien sun, revealing details of a 'hot Saturn' Words by Rafi Letzter NASA space observatory TESS has, for the first time, detected a planet orbiting a star with visible' starquakes. TESS, launched in April 2018, is just beginning to show scientists what it can do. Like its predecessor, the Kepler space telescope, the orbiting TESS detects planets by watching the brightness of their host stars dip as the planets pass between the stars and the telescope. Unlike Kepler, the TESS satellite focuses on a group of bright stars relatively close to Earth and spread across a wide span of the sky. TESS can also detect starquakes – seismic waves that pass through stars like earthquakes travel through Earth – by…

Key to life WHY WATER ISN’T KEY TO LIFE A new picture of our galaxy filled with exotic oceans and alien seas has raised questions about our focus on H2O in the search for life Reported by James Romero If there is magic on this planet it is contained in water,” observed Loren Eiseley, the great natural science writer, as he watched a beetle from his window bathing inside an algae-filled rooftop puddle. Where there is water, invariably there is life – on Earth at least. But what about other worlds? How far does this reliance on water extend out into the cosmos? These questions come into focus with new evidence that Earth’s water oceans might be relatively rare on galactic scales, where a wide variety of exotic and alien…

Cosmic storm A STORM IN A COSMIC TEACUP NASA's Chandra Space Telescope captures a tempest in the universe Reported by Samantha Mathewson © ESO A quasar has caused a raging storm in a distant cosmic structure known as ‘the Teacup’. The quasar, which is powered by a supermassive black hole, is located at the centre of a distant galaxy about 1.1 billion light years from Earth. The galaxy, formally known as SDSS 1430+1339, hosts a teacup-shaped structure, in which the quasar is brewing. Quasars are among some of the brightest and most distant objects known in the universe. They are found only in galaxies with supermassive black holes, which gobble up matter near the galactic core and emit extreme amounts of radiation, according to a statement from NASA. The signature…

Rocket science Bluffer’s guide to ROCKET SCIENCE Rockets of all kinds are still our only way of reaching space – but just how do they work? Written by Giles Sparrow © Belterz 1 How rockets lift off Rockets burn through most of their fuel in the first few minutes of their flight as they battle against Earth’s gravity © NASA; SpaceX; Adrian Mann 1 Gravity The force of gravity pulls everything towards the centre of the Earth, exerting a downward force of 9.8 newtons per kilogram on every part of the rocket. 2 Drag Earth’s air might be thin, but it can exert a strong resistance called drag against an object moving at high speed. Fortunately it reduces as the air becomes thin at higher altitudes. 3 Thrust The rocket…

STARGAZER Beat light pollution 10 TIPS TO BEAT LIGHT POLLUTION It's every astronomer’s enemy: here’s how to cheat your way to better views of the night sky – even from urban areas 1 Make use of shadow If you have streetlights shining into your garden, do your best to find a spot that’s not illuminated by these which can give you a good view of the sky. Getting into the shadow of a brick wall or a tree can help here. The side of a building can help too, but this can block your view of a large part of the sky, so you may need to hunt around for the best spot in your yard. 2 Wait for the right conditions Artificial light is shone into the sky and…

STARGAZER The Northern Hemisphere The warmer months have arrived - and an impressive array of targets are to be had Summer has returned, bringing with it warmer nights. While the cold evenings of winter provide dark skies and longer observing sessions, May still has a lot to offer in the way of vibrant nebulae, star clusters and galaxies. By mid-May at 10pm (BST), the constellations of Canes Venatici (The Hunting Dogs), Virgo (The Virgin), Coma Berenices (Berenice’s Hair) and parts of Centaurus (The Centaur) are in prime positions for viewing, offering a splendour of targets. Globular cluster Omega Centauri glows at magnitude 3.9 and makes its appearance from the east to set in the west. NGC 5128, or Centaurus A, contains multiple layers of dust and is one of the…

STARGAZER Sky-Watcher Startravel-102 (AZ-GTe) Designed to be controlled wirelessly with your smartphone, this highly portable refractor provides good Solar System views There are all kinds of factors that mean we live rushed observing lives, from the constant threat of encroaching clouds to the demands on our time from general life and work. Often when we go out under the stars, we want a 'scope that’s portable and quick to set up. Sky-Watcher’s Startravel-102, which comes on an AZ-GTe Go-To alt-az mount and an adjustable steel tripod, is the perfect ‘grab-and-go’ scope for beginners or casual observers. Weighing just 6.7 kilograms, it’s easy to carry outside – though if possible, and not too rushed, allow half an hour for it to acclimatise to the ambient temperature outside to avoid heat currents…

STARGAZER In the shops The latest books, apps, software, tech and accessories for space and astronomy fans alike Book Brief Answers to the Big Questions Cost: £14.99 (approx. $19.60) From: John Murray The world-famous cosmologist and number one bestselling author of A Brief History of Time leaves us with his final thoughts on the universe's biggest questions in this brilliant posthumous work. Is there a God? How did it all begin? Can we predict the future? What is inside a black hole? Is there other intelligent life in the universe? Will AI outsmart us? How do we shape the future? Will we survive on Earth? Should we colonise space? Is time travel possible? Throughout his extraordinary career, Stephen Hawking expanded our understanding of the universe and unravelled some of…