All About SpaceNo. 86的目錄

Welcome @ NASA; Noppawat Tom Charoensinphon Some weeks ago I was sitting with the All About Space team, talking about a new theory that seems to have been rattling around the scientific community for quite a few years: the rumour among astrophysicists is that our universe – and any other universes that surround us – could be inside a gravastar. Eyebrows were raised. How could we actually prove it? What made astrophysicists think that this could be a possibility? What actually is a gravastar? This issue All About Space finds out – turn to page 50 for everything you need to know as we unlock the evidence that's left cosmologists questioning what's at the very edge of the cosmos as we know it. The hunt for another world within our…

Approach to Bennu © NASA NASA’s long-awaited Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRISREx) has completed its 2 billion-kilometre (1.2 billion-mile) journey through the Solar System to the asteroid Bennu. After this image was taken on its approach at 80 kilometres (50 miles), OSIRIS-REx executed a manoeuvre that took it into a close orbit around the asteroid in order to investigate what these primordial time-capsules can tell us about our early Solar System.…

The solar north pole © ESA A number of missions have been created with one of the hardest objectives: to understand the true nature of the Sun. This sphere of intensely burning gas makes it hard for any mission to get close to it. ESA’s Project for Onboard Autonomy 2 (PROBA-2) has provided important low-latitude observations of the Sun that have led to an artificial view of the star’s north pole. Scientists are interested in how the star’s poles act in comparison to its equator, which scientists regularly observe.…

Interview Avi Loeb ’OUMUAMUA IS IT AN ALIEN LIGHT SAIL? Professor Avi Loeb discusses the controversy of ruling out every possible scenario in uncovering the origin of an extraterrestrial object that was spotted in our Solar System in 2017 - even the chance it could be a message in a bottle from an alien civilisation © ESO; LSST Corporation “It’s nothing that we have seen before in the sense that its shape is very extreme” For our readers, please could you provide a bit of background on ‘Oumuamua? It was discovered just a year ago, 19 October 2017, when it passed close to the Earth. It’s a relatively small object, tens to hundreds of metres. We don’t exactly know the dimensions because we don’t have any images of it. It…

Northern lights CHASING THE NORTHERN LIGHTS All About Space heads north to seek out nature’s greatest light show © ISSI; Peerasit Chockmaneenuch; Bokasana If there’s one thing on the bucket list for most, it’s seeing the northern lights. Also referred to as the aurora borealis, it instills a sense of wonder in the minds of many. Its characteristic and stunning green glow as it weaves its way through a sky above snow-capped mountains is a scene that many have admired in a photograph. Not many can say that they have had front-row seats to nature’s very own light show though. This is because you have to be in the right time and in the right place to see it awaken the sky with its shimmering dance. Keen aurora hunters often…

ASK Our experts answer your questions SPACE EXPLORATION How much has space exploration progressed since the Apollo missions? “It’s going to be a few years before they get the long-range exploration going” Well, it’s hard to tell. I think right now they’re focusing on getting commercial spacecraft to fly people to the space station, but in the background there is a long-range programme with [the Space Launch System rocket] and [the Orion spacecraft] that will eventually allow us to go beyond Earth orbit, like going to Mars. But right now it’s not an active part of launching because we’re between programmes I guess, and so it’s going to be a few years before they get the long-range exploration going with the new spacecraft. I would expect it’s going to be…

What is a gravastar? At the turn of the millennium an equally invisible, but potentially distinguishable alterative to black holes was proposed © NASA; JPL-Valtech; LIGO; Rastan; PaladinDeGigantas A surface you would notice While you would fall into a black hole, a gravastar’s vacuum interior is wrapped inside a shell of quantum matter which you would definitely feel upon impact. A black star The strength of a gravastar’s gravitational field means no light coming from them would ever reach us. Freed from the singularity Unlike classical black holes gravastars don’t contain a singularity, a point of infinite density that breaks our current laws of physics. Making waves Supporters of the theory believe the merger of two gravastars could also have produced the gravitational waves recorded by LIGO. A prediction 100…

How to… Get into Martian orbit Brace for arrival Mangalyaan had journeyed for over ten months, travelling 667 million kilometres (414 million miles) across the Solar System. Reorienting Mangalyaan Upon approach the craft needs to readjust its position so that the thrust vector can be made effective before the engines fire. Reducing the speed For 24 minutes the liquid engine and eight thrusters are fired to slow down the spacecraft, and ends with the craft placed into an orbit roughly 970 kilometres (600 miles) above Mars. Blackout in communication For 20 minutes during this engine burn Mars is stopping communications between the spacecraft and Earth. However, the scientists have prepared the spacecraft for this blackout in order to continue operations. Fixing into position After the burn the spacecraft is reorientated…

How to… Photograph dawn’s Moon and planets At the end of the month there will be a meeting between three bodies in our Solar System before sunrise. Here’s how to capture the stunning celestial close encounter © ESO Cross your fingers for clear skies on the last two mornings of January; if the weather cooperates we’ll be able to see something very pretty – a gathering of two bright planets and the Moon low in the southeast before sunrise. You’ll need no special equipment to see this cosmic collection because all three objects are easily visible to the naked eye, but if you want to photograph it you will need a good camera on a tripod, and a suitable observing site too. Seeing the Moon and planets will mean a…

STARGAZER Astroshots of the month Anvar Ghadery Western Azerbaijan, Iran “I’m an astrophotographer and enjoy shooting nightscapes, in particular the Milky Way and Iridium flares, framed by the stunning landscape of western Azerbaijan. My image reveals a place where borders no longer have meaning – a river on the Iranian border with Iraq. A river that simply crosses the borders of two countries, our galaxy hangs beyond.” Jamie Cooper Northamptonshire, UK “I first became interested in astronomy as a boy when my father, who was a keen amateur astronomer, first showed me the amazing views that could be seen through a backyard telescope. There was something magical for a small boy seeing mountains and craters in fine detail on the Moon. The first views of Saturn with its rings and…

STARGAZER Takahashi FS-60C Exuding quality, this apochromatic refractor is of exceptional optical and mechanical performance – perfect for the intermediate astronomer From the moment we unpackaged the Takahashi FS-60C we were in awe of its superb quality; with its pearly white finish, complete with the classic green accents on the lens cover and focuser that manufacturer Takahashi are famous for, this refractor is an impressive piece of workmanship. Of course, being an apochromatic means that you’re getting the best in telescope optics – boasting superb clarity and contrast and a way of keeping colour-fringing, also known as chromatic aberration, at bay – and lending itself to a high retail price for the tube alone. However, if you’re an astronomer who is on the hunt for the very best views of…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE California fires watched from space © NASA In November 2018 California experienced one of the fiercest fires to ever plague its forests. The fire, nicknamed the Camp Fire, took over an astounding 140,000 acres (218 square miles) after just eight days. This was one of the deadliest and most destructive fires in Californian history and was eventually subsided on 25 November 2018. NASA was able to observe the blaze from above using the MODIS instrument on the Terra satellite, creating the natural-colour image shown here. Any active fires are shown as red dots within the image; these were detected using thermal bands.…

P-RIME time for testing antennae © ESA The JUpiter ICy moons Explorer – or JUICE – spacecraft is ESA’s next mission to the exciting Galilean moons of Jupiter. JUICE will visit the moons Ganymede, Europa and Callisto, which have proposed subsurface oceans that could even support life as we know it. Ahead of its launch, ESA has been developing the Radar for Icy Moons Exploration (RIME) instrument on JUICE. This radar antenna will pierce through their icy crusts in order to examine the contents as deep as nine kilometres (5.6 miles), hopefully relaying exhilarating news of the environment below.…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE Four new kinds of gravitational waves detected from crashing black holes It’s the largest batch of detections released at once and includes an event that is both the most massive and the most distant collision observed to date © © N NA AS SA A;; LIGO/Caltech; CIMON; Mark A. Garlick / space-art.co.uk “Gravitational waves give us insight into the population and properties of black holes” Scientists have identified four more signals of massive collisions in outer space, including the largest to date, bringing the total of gravitational-wave detections to 11 in just a few years. A team of researchers affiliated with the Laser Interferometer Gravitational-Wave Observatory (LIGO) in the US and its European counterpart Virgo unveiled the four new detections on Saturday…

LAUNCH PAD YOUR FIRST CONTACT WITH THE UNIVERSE Nearby planet probably wet and life-friendly TRAPPIST-1e may host liquid water on its surface One of seven planets orbiting a small star, TRAPPIST-1, may be capable of supporting life, new climate models suggest. Using terrestrial climate and photochemistry models, researchers from the University of Washington simulated environmental states for each planet of the TRAPPIST-1 system. The models show that all seven exoplanets likely evolved like Venus, meaning that any water or oceans would have evaporated early on in the system's formation, the research team said. According to these models the seven planets of TRAPPIST-1 would have dense, uninhabitable atmospheres. However, one of the worlds, TRAPPIST-1e, may host liquid water on its surface and, as a result, be able to support Earth-like life.…

Planet X THE HUNT FOR PLANET X Could this hidden planet really exist? All About Space meets the scientists who could be on the trail of an undiscovered world Reported by Jonathan O’Callaghan © Tobias Roetsch Astronomers have long wondered if our Solar System could contain a missing, unseen planet. A century ago some were convinced there was a gas giant lurking in the outer reaches, before later being derided for such a suggestion when it proved false. But now momentum is building that there may be another planet that has been hidden from our view and, while we haven’t found it yet, we can see its fingerprints all over the outer Solar System. This is Planet Nine, which was first seriously proposed by astronomers Mike Brown and Konstantin Batygin…

Planet X Planet Nine’s orbital path How we think this world dances around the Sun Closest point At its closest point to the Sun, known as a perihelion, Planet Nine is predicted to approach to about 200 AU away. Farthest point Planet Nine’s orbit is thought to extend out to a distance of up to 1,200 AU from the Sun into the far outer Solar System. The next-nearest planet Neptune’s orbit only takes it out to about 30 AU, more than six-times less than the perihelion of Planet Nine. The inclination Compared to the other planets of the Solar System Planet Nine is thought to be inclined by about 30 degrees. The shape of its orbit Planet Nine is thought to have a highly eccentric orbit, completing one revolution around…

INTERVIEW BIO Professor Abraham (Avi) Loeb Avi Loeb is an Israeli-American theoretical physicist and the Frank B. Baird Jr. Professor of Science at Harvard University, Cambridge, Massachusetts, United States. He is involved in many other astronomy organisations as well, including being chair of Harvard’s Department of Astronomy, founding director of the Black Hole Initiative and chair of the Advisory Committee for the Breakthrough Starshot Initiative, to name a few. Loeb’s work in theoretical physics has led him to study many aspects of space, from exoplanets to black holes. In 2012, Time magazine also selected Loeb as one of the 25 most influential people in space science.…

Northern lights Top places to see aurora borealis Take a trip to the Arctic Circle for your best chance of catching the northern lights “ The northern lights usually make their appearance during the winter months through late March or early April” Norway The aurora borealis is at its most active between late autumn through to early spring, with many taking the opportunity to hunt for the lights at around 6:00pm to 1:00am between the equinoxes. While you will be able to see the northern lights from any location in Norway, the best locations are above the Arctic Circle in northern Norway or the Svalbard Islands. It’s said that there’s no other place on Earth that offers better chances of spotting the lights since the aurora borealis belt hits Norway’s…

Northern lights Lights, camera, action: imaging the northern lights Get those vivid greens, purples and reds in your shots ©Bokasanal; Timo Newton-Syms; Luc Viatour / https://Lucnix.be; FairbanksMike It’s easy to be unprepared when it comes to imaging the northern lights, and though it’s true that the advent of the digital camera has reduced the trial and error that comes with slide films, capturing the northern lights still takes practice, planning and patience. It’s a given that to get the best displays of the northern lights possible you should find a location within the auroral belt as well as avoiding any light pollution from the Moon or artificial sources, such as street lights. A great proportion of your shooting will be between northwest and southeast directions in the sky, so with…

Avatars in space Construction of AVATAR X The four stages of this programme aim to build a whole new interface for interacting beyond the realms of Earth Assembling the consortium Uniting all the organisations – including JAXA, XPRIZE, Meltin and others – to one common goal with a unified game-plan could prove difficult, but this is the start of the plan to make the ANA-JAXA AVATAR X program a reality. Testing in low-Earth orbit Once the technologies have been developed it is then time to put them to the test. For this the technologies will be launched into low-Earth orbit, the home of many satellites and the ISS. These avatars will have the capability of repairing and maintaining such apparatus. Building the base The AVATAR X LAB @ OITA will…

Focus on InSight INSIGHT HAS LANDED AND IS READY TO PROBE MARS NASA’s highly anticipated InSight lander has finally touched ground on the dry Red Planet Scientists rejoiced as NASA’s Seismic Investigations, Geodesy and Heat Transport (InSight) lander successfully landed on 26 November at Elysium Planitia, bringing about a whole new outlook on investigations of the Red Planet. After a seven-month, 485-million-kilometre (300-million-mile) journey InSight had to take on the hardest challenge for a Martian lander: reducing its speed through a virtually nonexistent atmosphere for a safe landing. “We hit the Martian atmosphere at 12,300 miles per hour [19,800 kilometres per hour], and the whole sequence to touching down on the surface took only six-and-a-half minutes,” says InSight project manager Tom Hoffman at NASA’s Jet Propulsion Laboratory in Pasadena, California,…

USER MANUAL Mangalyaan India’s first Mars orbiter, also known as the Mars Orbiter Mission, defines ‘cheap and cheerful’ in space exploration On 5 November 2013 the ISRO launched its maiden interplanetary mission to Mars. This was an incredible feat not only for India, certifying its position as a serious presence in space, but for space travel, proving that a task like this can be completed on a relatively cheap budget. At the tip of a PSLV-C25 rocket, carrying 12 tonnes of propellant, was India’s Mars Orbiter Mission, also referred to as Mangalyaan, which means ‘Mars-craft’ in Hindi. After completing the 667-million-kilometre (414-million-mile) journey through space over the course of just over ten months Mangalyaan was inserted into the orbit of Mars, and India rejoiced at its first interplanetary craft being…

TOP TECH Mars Colour Camera During its four-year mission, Mangalyaan's MCC has acquired more than 980 images using its 16 different exposure modes. Specifically, the camera incorporates an electro-optical sensor that images the Martian surface in three colours, red, green and blue, and offers a spatial resolution that varies between 20 to 4,000 metres (66 to 13,133 feet). The main science objectives of this camera are to unveil the secrets of Mars' surface features, and monitor the dust and clouds around it. One of its key achievements was spotting that the clouds over different mountains, for example Olympus and Elysium Mons, have a unique morphology.…

Instant Expert Time dilation What happens to time when travelling at extreme speeds? All About Space has asked a scientist to break it down in terms of twins Martin and Carlos are identical twins. Well, almost. While Martin is a medical doctor, Carlos is an astronaut about to travel to Alpha Centuari, the nearest star system to our own, at speeds nearing that of light. Just before takeoff Martin and Carlos synchronise their watches, and Carlos reminds Martin that Einstein’s theory of special relativity predicts ‘time dilation’, that is, that watches moving at a constant high speed appear to tick at a slower pace. This gets Martin thinking… With Carlos moving rapidly his watch will run slower, which means that he will be younger upon his return! But from Carlos’…

Quickfire questions with the kilonova discoverer Dr Eleonora Troja is an associate research scientist in the Department of Astronomy at the University of Maryland, and works primarily at the NASA Goddard Space Flight Center in the Astrophysics Science Division What are the similarities between GRB150101B and GW170817? We think that in both cases the jet was not pointing toward us, but was slightly tilted. In all previous cases of GRB explosions the jet was always pointing straight toward us, and its light was outshining everything else. It was like someone pointing a flashlight straight into our eyes – we could not see anything else but the bright light. In GRB150101B and GW170817 the different jets’ orientations caused the light to look dimmer for us, and this unveiled the other facets…

Moon tour Copernicus As 2019 begins we pay our respects to ‘The Monarch of The Moon’ If you’ve ever seen a TV documentary about the Moon you’ll have seen a space boffin enthusiastically hurling a stone into a tray full of flour to demonstrate how impact craters are formed. Of all the hundreds of thousands of craters on the Moon, one looks exactly like the feature these dramatic demonstrations produces – a deep, sharp-edged pit, like a skull’s eye socket, surrounded by rays of debris. Copernicus looks exactly like a lunar crater should: a great hole in the Moon with a dark, shadowed floor; a high, sky-scratching rim and lots of bright rays of dust and pulverised rock splashing away from it. Its nickname, The Monarch of the Moon, is…

Io rises above the storms of Jupiter © NASA/JPL-Caltech The four Galilean moons of Jupiter are four exciting worlds. Due to their close proximity to the enormous gas giant and their relatively large sizes, these moons are as interesting as they come. Io is the innermost moon and therefore experiences the most intense effects of Jupiter’s gravity, exhibiting unusually powerful volcanic activity. On 29 October 2018 NASA’s Juno spacecraft made its 16th close passage over the cloud tops of Jupiter and captured the moon, slightly larger than our own Moon, rising over the gas giant's limb.…

ExoMars under the Spanish Sun ©ESA As the Sun set on a week of trials for the European Space Agency’s (ESA) ExoMars rover prototype, nicknamed Charlie, scientists are excited about what is to come from the future mission. During a ten-day field trial taken in the Tabernas Desert in Spain, nicknamed ExoFiT, scientists were practising driving the rover, targeting areas of interest and sampling rocks. Although there were environmental issues such as rainfall the team were able to optimise their time and test a variety of instruments that will search for signs of life on the surface of Mars.…

Hubble spots drifting orphaned stars Over 22,400 globular clusters have been spotted An enormous cosmic neighbourhood that's home to more than 1,000 gravitationally bound galactic neighbours is bursting with thousands of stray star clusters, images from the Hubble Space Telescope have revealed. While conducting a comprehensive survey of the Coma Cluster of galaxies astronomers using the Hubble Space Telescope counted 22,426 globular star clusters scattered throughout the space between those galaxies. Each of those dense, spherical groups contains hundreds of thousands of ancient stars that huddle together because of their mutual gravitational attraction, much like the larger galaxies that make up the Coma Cluster. Located more than 300 million light years from Earth in the constellation Coma Berenices, the Coma Cluster is one of the first places where scientists found…

What could this other world be made of? Here’s what we know and don’t know about the potential ninth planet The mass The planet is thought to have a mass of between 5 and 15 Earths, which could make it a so-called super-Earth. Cold as ice Being located beyond the orbit of Neptune, it's likely to be extremely cold – any water the planet has will be frozen as ice. On the surface If the planet is smaller than 1.6 Earth radii it might have a rocky surface. If it’s larger, it could be more similar to a gas giant. Inside the planet As we don’t know the planet’s radius, we can’t yet tell what its core, mantle or atmosphere (if it has one) look like.…

FUTURE TECH Virgin Orbit VIRGIN ORBIT TO LAUNCH SATELLITES Cosmic Girl and LauncherOne will combine to become a big player in commercial spaceflight © Adrian Mann Payload module Once the second stage thrusters are fired the clamshell halves separate to release the satellite at the tip of the rocket. It is capable of placing 300 kilograms (660 pounds) into Sunsychronous orbit or 500 kilograms (1,100 pounds) into low-Earth orbit. Second stage The final, less powerful thruster will fire the second stage to orbit, with NewtonFour delivering 22 kilonewtons (4,900 pound-force) of thrust. First stage Once reaching a 9,100-metre (30,000-foot) altitude the NewtonThree rocket will fire its pump-fed LOX/RP-1 liquid rocket engine. The NewtonThree engine produces 330 kilonewtons (74,000 pound-force) of thrust. In the expanding race for commercial space flight it…

Avatars touch down When these robots are up and running, they will unveil a new era in space exploration © MELTEN/JAXA Rover repairs Avatars can perform remote repairs, giving an extended lifespan for any rovers on the Moon, Mars or farther away. Human control Human intelligence with robotic accessibility presents the best of both worlds, allowing for greater exploration of space. Unknown terrain Terrain on the Moon or Mars is virtually unknown. With avatars we could properly scan areas for any boulders or depressions.…

Gravastars DO WE LIVE INSIDE A GRAVASTAR? An incredible finding could mean that we’re not only questioning the existence of black holes, but also the structure of the universe as we know it Reported by James Romero © Rastan In 2001 two physicists proposed a solution to 70 years of debate around black holes, the most extreme, mind-bending objects in the universe, by replacing them entirely. Their alternative, named a gravastar, could solve fundamental paradoxes raised by Stephen Hawking. Some even believe our entire universe may exist inside one. Now, after time out of the spotlight, interest in gravastars is returning, fuelled by the real possibility we could soon prove their existence once and for all. An insatiable appetite and the ability to bend reality, virtually stop time and turn people…

Our universe inside a gravastar Why some believe gravastars could overturn our thinking on cosmology, inflation and the Big Bang © NASA; Tobias Roetsch Mottola and Mawar included some intriguing speculation that, if correct, could explain the Big Bang and the effects of inflation and dark energy. While Russian physicists back in the 1960s had noted the similarities of the Big Bang and black hole singularities, gravastars’ repulsive negative pressure in a vacuum provided a familiar environment for the birth and rapid expansion of our universe. Could gravastars not only populate our cosmos, but house it too? Negative gravity The phase change brought about by gravitational collapse of the dying star creates a negative pressure within the newly formed vacuum bubble at the gravastar's centre, essentially a form of repulsive…

Anatomy of a Martian Orbiter Similar to the structure of India’s lunar mission, Chandrayaan-1, Mangalyaan is still operating in orbit around Mars Lyman-Alpha Photometer (LAP) The LAP will determine the relative abundances of deuterium and hydrogen in the upper atmosphere of Mars. This will help determine the escape rate of water from the planet. Propellant tank With a capacity of 390 litres, the spacecraft was launched with 852 kilograms (1,880 pounds) of fuel. The bi-propellant (monomethyl hydrazine and nitrogen tetroxide) provides 440 Newtons of thrust. Mars Exospheric Neutral Composition Analyser (MENCA) This quadruple-mass spectrometer is capable of resolving the neutral composition of particles in the range of 1 to 300 atomic mass units. Solar array Three solar panels measuring 1.8 by 1.4 metres (6.0 by 4.6 feet) provide 840 Watts…

Head-to-head Mangalyaan vs Mars Reconnaissance Orbiter NASA’s Mars Reconnaissance Orbiter (MRO) arrived at Mars on 10 March 2006, giving it over eight-years more experience than Mangalyaan. It arguably has a more impressive instrumental suite than the Indian spacecraft. MRO carries six scientific instruments, having one more than Mangalyaan, but it is the High Resolution Imaging Science Experiment (HiRISE) camera which has continued to provide spectacular high-resolution images of the Martian surface. Although MRO seems to be better in terms of quality, Mangalyaan is significantly cheaper, being roughly ten-times less expensive than the MRO.…

How to… Capture this month's total lunar eclipse In the early hours of 21 January the full Moon will grow dark and turn orange as it moves through Earth’s shadow - don't miss it! © Giuseppe Donatiello January can be a very unsettled month when it comes to the weather, but when the sky is clear the temperature plummets, leaving behind an inky-black sky strewn with stars as bright and colourful as jewels. As if that wasn’t enough to look forward to, on the morning of 21 January we’ll have a chance to see a total eclipse of the Moon. Lunar eclipses occur when the Moon passes through Earth’s shadow. If the Moon only moves part of the way into that shadow we only see part of its bright face…

Deep sky challenge Unveil deep-sky treasures hidden in and around Orion As gorgeous as it is, there’s more to see in this part of the sky than the Hunter's nebula When you take your telescope outside on a frosty, sparkling, clear January night and see the jewelled stars of Orion blazing in the south, it’s tempting to swing it towards the same old targets you always look at in winter, especially the misty grey-green swirls and whorls of the beautiful Orion Nebula (M42), glowing softly in the centre of Orion’s very short sword, hanging from his much more famous belt. That’s understandable; after all it is one of the most stunning deep-sky objects in the whole of the sky. But if you take a deep breath and dare to drag…