Discoveries that comply with cosmological models are like a scientific pat on the back. But the ones that don’t hold up to previous standards excite the imagination the most because they imply a more mysterious, dynamic, and maybe even scarier universe.Sometimes, we get a little too sure of our scientific knowledge. These latest discoveries show us just how much we don’t know and how much we’ll have to rethink our previous theories about the final frontier.
A Supernova Birthed Our Solar System
Every cosmic catastrophe is just the birth of some other phenomenon. A supernova, for example, might spark a solar system into life. Our solar system. The solar system began as a debris cloud, which coagulated into countless bodies that drifted together or apart to form the eight planets and miscellaneous rocks we call home. But that process needed a catalyst.Like a supernova. The evidence comes from isotopes in ancient meteorites. One of these is iron-60, which decays into nickel-60 and is produced by certain stars and supernovae. The meteorites contained this telltale nickel-60, suggesting a supernova shock wave punched the solar system to life. This implies that supernovae across the universe could be continuously birthing new solar systems.
Proxima b Is Probably Scorched And Barren
Only 4.2 light-years away, the red dwarf Proxima Centauri is our closest stellar neighbor. And it harbors an Earthlike habitable zone planet, Proxima b.But it’s probably barren. In March 2017, astronomers watched Proxima Centauri grow 1,000 times brighter over a 10-second span, suggesting either a catastrophic flare or extraterrestrial weapons testing. In spite of the star’s small mass, the eruption was 10 times larger than the Sun’s mightiest outbursts.At 4.85 billion years old, Proxima b has probably been absorbing similar hits for eons now. Its atmosphere and water would have long been stripped away by the intense radiation. So the relativistic probes of the future are unlikely to find any interesting biology at their first destination.
Super-Gigantic Stars Are Surprisingly Plentiful
The universe appears to be far more spangled with massive stars (10 or more solar masses) than formerly indicated. Astronomers surveyed the 180,000-light-year-distant Tarantula Nebula (aka 30 Doradus), a prominent stellar nursery, and found 30 percent more “extremely, extremely massive stars” than expected.And the most massive stars are getting upgraded. It was believed that 200 solar masses was the upper limit, but astronomers are raising that figure to 300 solar masses. This implies a much more violent universe with 70 percent more supernovae and an 180 percent increase in black hole formation.
The Universe Is Teeming With Synestias
Planetary bodies came in about two flavors, planets and ringed planets. But that family just expanded with the addition of the synestia, a much bigger cloud of vaporized rock shaped like a red blood cell.These wispy monsters are the result of catastrophic crashes between two rapidly spinning, planet-sized chunks. The angular momentum from each body is conserved and whips up their shattered remains into a puff of molten debris “with no solid or liquid surface.”It’s crazy to think that there’s a theoretically super-common, entirely new type of planetary body that we haven’t directly observed yet. Probably because it doesn’t last very long, maybe only 100 years, a hilariously infinitesimal span in cosmic terms.
Stars Can Be Smaller (And Colder) Than Planets
We picture even the wimpiest stars being far more substantial than, say, a planet. But astronomers have just discovered the cutest, littlest star ever, EBLM J0555-57Ab.It’s only 600 light-years away, and its radius and mass are only about 8 percent that of the Sun. In fact, it’s so small that it’s only a hair larger than Saturn. So it wouldn’t even be the largest planet in our solar system thanks to Jupiter. It’s even colder than some gas giant exoplanets.EBLM J0555-57Ab really straddles the threshold of stellar mass, just barely beefy enough to fuse hydrogen into helium and avoid a fate of undignified brown dwarfiness.[
TRAPPIST-1 Is Too Old For Life
The seven-planet TRAPPIST-1 system discovered in February 2017 is a prime suspect in the search for alien life, with multiple potentially habitable planets. At least it was when its age was estimated at 500 million years old. But new criteria, including the system’s speed around the center of the galaxy, the star’s metal content, and chemical absorption lines, suggest that the TRAPPIST family is at least as old as our solar system and potentially twice as old at 9.8 billion years. So it’s unlikely to host life as it was probably sterilized by flares long ago, a cosmic tragedy and reminder of how rare life may be.
Dark Matter May Be Disappearing
Dark matter seems immortal and ever present, but a new monkey wrench in the gears paints dark matter as an unstable entity. Fluctuations detected 300,000 years after the big bang didn’t match the speed of expansion of the universe given by models. This can be explained by decaying dark matter, which existed at the dawn of time but has since decayed into neutrinos or hypothetical particles.The analysis says the current universe is 5 percent poorer in dark matter because some of it decays and some of it doesn’t. These unstable constituents may have all died out after the first several hundreds of thousands of years. Then again, maybe they didn’t because they may still be decaying and constantly changing the layout of the future universe.
The First Exomoon?
The spaceborne Kepler spacecraft has discovered thousands of exoplanets but no exomoons, which might be because they’re hiding around the planets farthest out from their stars. Recently, Twitter broke the news that astronomers may have detected the first extrasolar moon. They discovered a planet candidate, Kepler-1625 b, which obscures a curious amount of light from its star. The lopsided light dip outlines Kepler-1625 b as a heaving Jupiter-size body with a Neptune-size companion moon. Astronomy is finally on the brink of glimpsing alien moons. This means a significant boost in the search for habitable bodies, though further review with Hubble is necessary to consolidate the claim.
Dark Energy Is Acting Up
The universe is expanding more quickly than it should, and no one knows why. Astronomers have been using Hubble for the past six years to improve the accuracy of expansion parameters. They calculated that the universe is expanding at a rate of 73 kilometers (45 mi) per second per megaparsec. So two galaxies separated by 3.3 million light-years, or one megaparsec, are flying apart at 73 kilometers (45 mi) per second.That’s an irreconcilable 9 percent discrepancy compared to Planck satellite predictions, with only a 1-in-5,000 chance of error. The study implies that dark energy is even more confounding that previously thought. Maybe it’s growing stronger. Or maybe it’s more “sociable” than thought and is interacting with the universe in a novel way. Or an entirely new type of particle could be at fault.
All Sunlike Stars Have Siblings
Lots of stars have companions, potentially even the Sun. A new study says that it does because all Sunlike stars are born binary. Astronomers surveyed young single stars and binaries in the Perseus constellation 600 light-years away, but the math makes the most sense when all Sunlike stars are born as “wide binaries” approximately 500 astronomical units apart (1 AU = 150 million kilometers (93 million mi)).But the partnerships either shrink or break apart early in their lifetime, after only about a million years. And a long-lost sibling could better explain the current state of our own solar system. Though the universe is still an overwhelmingly lonely place and the model suggests that 60 percent of these pairs eventually split up, the remaining stars shrink into “tight binaries.” Meanwhile, our Sun’s theoretical companion, Nemesis, may be lost among the other stars in our galaxy.
Best space discoveries of 2017
From neutron stars colliding to our solar system’s first visitor, 2017 was an amazing year for space discoveries. While the year had some sad moments, like the end of the 20–year long Cassini mission, we also learnt a huge amount about this vast Universe in which we live. Here's the best of space in 2017.
Physicists detect gravitational waves as neutron stars collide
Gravitational waves produced by two neutron stars colliding have been detected for the first time. The detection, by the Ligo team, has confirmed long-held theories about what happens when two of these powerful objects come together.
Neutron stars are the strangest stars in the Universe. Produced when the largest stars come of the end of their life, run out of fuel and collapse in on themselves, neutron stars are the smallest and most dense stars can get. Just one teaspoon of neutron star material is as heavy as the Great Pyramid of Giza.
The gravity from a neutron star is almost as intense as a black hole, and when two of these powerful objects come into contact with each other they start a dramatic dance, swirling around drawing each other closer together until, eventually, they merge.
When two neutron stars merge, just like two black holes merging, they give off gravitational waves; tiny ripples in spacetime predicted by Einstein over 100 years ago. It was also predicted this merge would spew out radioactive material, part of an explosive event known as a kilonova.
The Nobel Prize for Physics this year was awarded to the Ligo team that has now spotted three instances of gravitational waves coming from black holes merging, the first of which was announced in February 2016.
Now, the team has spotted the gravitational waves from the merging of neutron stars for the first time. Not only this, but the team were also able to detect electromagnetic radiation coming from the event and gamma ray bursts given off just seconds later.
"This kind of event is one that scientists working in this field have been hoping for - but it took nature to be pretty kind to give us one at just the right time with the LIGO and Virgo observatories operating together for the first time," says Professor Sheila Rowan, director of the University of Glasgow’s Institute for Gravitational Research.
Back in August, the Ligo team spotted the merging of two neutron stars in the galaxy GW170817, which lies 130 million light years away. The complete details of this event are described in seven new papers, published today in Nature and Nature Astronomy. The event was observed in a variety of wavelengths, including optical, infra-red and X-ray, and it was seen to turn from blue to red during the event.
On top of being a breakthrough in detecting different kinds of gravitational waves, the new papers offer potential answers to a variety of questions. For example, the origin of some of the heaviest elements in the Universe has long been misunderstood, and now it seems they may be formed in neutron stars.
"Detecting gravitational waves from neutron stars rather than black holes gives a different and rich set of science, due to the fact that this time we are witnessing the collision of matter - and that means along with the gravitational signals come light and other electromagnetic waves which are picked up by telescopes. This truly marks the start of multi-messenger gravitational astrophysics," Rowan says.
Another mystery is that gamma ray bursts often appear dim from Earth, and these results show that a fast jet of material was probably observed off-axis, meaning they might not have been fired in the direction we expected, therefore appearing dimmer.
“GW170817 represents a remarkable opportunity to make major progress in multiple fields of physics and astrophysics, and it whets our appetite for the many expected observations of neutron-star mergers in future campaigns,” says Professor M Coleman Miller, who was not involved in the research.
"It is an epochal finding," says Stefano Covino from the Instituto Nazionale di Astrofisica, Merate, Italy. "Both because this is a very interesting astrophysical source, but also, if not mainly, because this is the beginning of a new kind of astronomy. The multi-messenger astronomy, where information coming from different “messengers” as gravitational way, photons, or neutrinos can be put together. This opens perspectives for modern research that are truly amazing."
A super-Earth found 40 light years away
A newly discovered exoplanet is causing excitement among astronomers as it has the potential to give us the best opportunity ever to find alien life.
The 'super-Earth', which is around 1.4 times the size of Earth but seven times its mass, is rocky, temperate and orbits a quiet star in our galactic neighbourhood.
“I am really, really excited about this discovery,” David Charbonneau, study author and professor of astronomy at Harvard University told WIRED. “This is the one we've been hunting for all these years!”
The rocky planet, named LHS 1140b, orbits a red dwarf star 40 light years away. While this is close in astronomical terms, what makes it so special is we do not need to go there to look for life.
“It orbits a nearby star which it passes in front of,” continued Charbonneau. “This special geometry means we can study its atmosphere to look for the chemical fingerprints of life, such as oxygen."
In particular, because the star transits in front of its star, astronomers can study to see if it has an atmosphere and, if so, what molecules are present. The orbit is seen almost edge-on from Earth and as it passes in front of its star, every 25 days, it blocks a portion of the star’s light. The planet’s mass and its temperature mean it is likely to have an atmosphere. The super-Earth is also orbiting at the right distance from its star needed for liquid water to be present on its surface – known as the habitable zone.
This is not the first time we have found a potentially habitable planet in the nearby part of the galaxy. Earlier this year, Nasa announced the discovery of exoplanets around a star called Trappist-1. Last year, a potentially habitable planet was found orbiting our nearest star, Proxima Centauri.
“But for Proxima Centauri b, we only know the minimum mass and for the Trappist-1 planets, we know their size and their mass is not very well known – except for one, which we know isn't rocky," fellow author Xafier Bonfils from the University of Grenoble told WIRED. "This is the first time we have detected a planet where we actually know it is both temperate and rocky.”
There's more. The super-Earth exoplanet is orbiting a red dwarf star, much smaller than our Sun. The star is ‘quiet’, meaning it rotates slowly and does not give off solar flares. This is also promising in the hunt for potential life.
“Compared to recent discoveries like Trappist-1 and Proxima Centauri, the star LHS1140 should not emit high energy radiation that can blow up an atmosphere and sterilize the planetary surface,” Nicola Astudillo-Defru from the Geneva Observatory told WIRED.
The discovery was first made with the MEarth facility, in Arizona, which detected the dips in light as the exoplanet passed in front of its star. ESO’s HARPS instrument, the High Accuracy Radial velocity Planet Searcher, later made follow-up observations that confirmed the presence of the super-Earth.
“We will have a first attempt to detect such an atmosphere with Hubble Space Telescope this year, and next with the James Webb Space Telescope,” Bonfils told WIRED. “Eventually, since it's a transiting planet, we have the possibility and we aim to characterise the composition of this atmosphere.”
If signs of life are found in the planet’s atmosphere, it might be possible to send a probe to explore further. The star, called LHS 1140, lies in the faint constellation of Cetus, also known as The Sea Monster.
“If we shrank the galaxy to the size of the United States, the distance between this new system and the Sun would fit inside Central Park,” Charbonneau told WIRED. Still, travelling at 10 per cent of the speed of light, it would take hundreds of years to reach the planet.
There have been suggestions in recent months that a lightweight solar-powered probe could travel this kind of distance in a much shorter time. However, more work needs to be done before a probe like this could be considered.
“The farthest we've ever sent humans is the Moon, 1 light second away,” explained Charbonneau, “and the farthest we've sent spacecraft is the edge of the Solar System - about seven light hours. So, it still is far from the perspective of a probe.”
"For now, we do not have the technology to travel at a velocity close to the speed of light," Astudillo-Defru said.
Ten new possibly habitable planets found
The ten planets are at just the right distance for liquid water to exist on their surfaces
Ten potentially habitable worlds have been announced today by Nasa. They are part of a group of 219 exoplanets revealed by the space agency in its eighth Kepler planet catalogue.
The ten planets are Earth-sized and in the habitable zone of their stars. This means they are at just the right distance for liquid water to exist on their surfaces.
Just under half of these are orbiting G dwarf stars – stars the same size as our Sun.
“The Kepler data set is unique, as it is the only one containing a population of these near Earth-analogues - planets with roughly the same size and orbit as Earth,” said Mario Perez, Kepler program scientist in the Astrophysics Division of Nasa’s Science Mission Directorate.
“Understanding their frequency in the galaxy will help inform the design of future Nasa missions to directly image another Earth.”
Nasa's Kepler space telescope has now discovered 4,034 candidate exoplanets. Out of these, 2,335 have been confirmed as planets, and are located in the Cygnus constellation.
Another study released today shows that most of these 2,335 planets fall into two distinct categories: rocky super-Earths, and mini-Neptunes that seem to have no surface. Despite not existing in our own Solar System, mini-Neptunes appear to be the most common planet in the galaxy.
“We like to think of this study as classifying planets in the same way that biologists identify new species of animals,” said Benjamin Fulton, a doctoral candidate at the University of Hawaii in Manoa, and lead author of the planetary categories study. “Finding two distinct groups of exoplanets is like discovering mammals and lizards make up distinct branches of a family tree.”
Last year, researchers at Caltech predicted the existence of another planet in our Solar System, lying far beyond Neptune. During a live stream, Fulton said the yet-undiscovered ‘planet nine’, if it exists, could be one of these mini-Neptunes.
One of the ten newly-announced planets, known as KOI7711, has the closest resemblance to Earth based on what the astronomers know so far. It is only 1.3 times the size of Earth.
Nasa hopes the catalogue, which is now complete with data from Kepler’s first mission conducted back in 2012, will help us in our search for alien life.
“This carefully-measured catalogue is the foundation for directly answering one of astronomy’s most compelling questions - how many planets like our Earth are in the galaxy?” said Susan Thompson, Kepler research scientist for the Seti Institute, and lead author of the study on the new planets.
Further data from Kepler’s second mission, K2, which started in 2013, will help further our knowledge of the exoplanets that are out there.
Jupiter's spot up close
In July, images from Nasa's Juno spacecraft revealed the gas giant in a completely new level of detail, showing its Red Spot to be "a tangle of dark, veinous clouds weaving their way through a massive crimson oval."
Since it arrived at the planet in July 2016 Juno has taken thousands of photographs and used eight on-board sensors to capture detailed readings about how it formed and its chemical composition. Its mission ends is February 2018 with a drive into Jupiter's atmosphere.
Water on the moon
The Moon holds more water than we thought in its interior, according to research published today, meaning humans could one day make the most of it as a space resource.
The study looked at a substance found on the Moon called pyroclastic deposits, which are made mostly of volcanic glass beads formed during ancient explosive eruptions. In the past, these have been thought of as potentially useful sources for elements like iron and titanium.
Now we have reason to believe they also contain water, that could be extracted by astronauts on the Moon.
Our Moon formed as the result of a giant impact with Earth, billions of years ago. This was a very high energy and high temperature process, and it is hard to envision how water could have survived it.
Because of this, it had been presumed that the interior of the Moon would have little water in it. But that view started to change in 2008 when professor Alberto Saal of Brown University studied volcanic glass beads brought back from the Moon by the Apollo mission, finding trace amounts of water.
The biggest question was whether or not these glass beads were representative of the interior of the Moon, or if they just happened to contain water in an otherwise dry body.
Now researchers have used satellite data to study more of the Moon’s surface, and found water-rich deposits spread across it. "By looking at the orbital data, we can examine the large pyroclastic deposits on the Moon that were never sampled by the Apollo or Luna missions,” said Ralph Milliken, from Brown University, lead author of the study.
“The fact that nearly all of them exhibit signatures of water suggests that the Apollo samples are not anomalous, so it may be that the bulk interior of the Moon is wet."
The presence of water on the Moon, and water in the deep interior in particular, is important because it tells us something about the fundamental processes that occurred during the formation of the Moon, and the earliest days of our solar system.
“The water somehow had to survive this process or, and perhaps more likely, the water was delivered to the Earth-Moon system by water-rich asteroids and comets after the impact event but before the Moon had completely cooled down and solidified,” Milliken told WIRED.
To determine how much water is in a planet or moon, astronomers use spectrometers to measure the light that bounces off the planetary surface. By looking at the wavelengths of light absorbed or reflected by a surface, scientists can work out which compounds are present. This was made trickier on the Moon, because its surface is warmed during each day.
Milliken says the most exciting part of this discovery is the potential use for humans. “The amount of water in a given glass bead is not very much, but the pyroclastic deposits are huge, so you have a lot of material to work with,” he told WIRED.
“Water is heavy and expensive to carry with you from Earth, so any water that can be extracted at the lunar surface is a huge help for developing a sustained presence beyond Earth.”
The end of an era for Cassini
It's been almost 20 years since Nasa's Cassini mission launched into space. In this time the spacecraft has traveled more than one billion miles and helped reveal the secrets of Saturn and its moons.
The science from the space agency's probe has been an overwhelming success (and there's still more to come). But every mission has to have an end, and Cassini's is imminent. And you can watch it all live using the video above.
For the curious, here's how Cassini's last few minutes are going to go down...
Having completed its final orbit around Titan on September 11, the craft has been heading back towards a collision course with Saturn. This is part of its grand finale. The end of the mission will see Cassini enter Saturn's atmosphere and at around 950 metres above the cloud tops it will lose contact with Nasa and begin to burn-up.
Nasa scientists expect to lose contact with Cassini at around 12:55PM UK time and are live streaming footage from mission control.
Earlier this morning, Cassini's onboard computers recalculated themselves to be able to transfer scientific data back to Earth in real-time. The change is allowing Cassini to give planetary researchers the most detailed data ever on Saturn's atmosphere.
"The mission team hopes to gain powerful insights into the planet's internal structure and the origins of the rings, obtain the first-ever sampling of Saturn's atmosphere and particles coming from the main rings, and capture the closest-ever views of Saturn's clouds and inner rings," Nasa explains on its website.
Nasa decided Cassini's mission should end this way long before the mission got to this stage. Instead of keeping the mission going and potentially colliding with one of Saturn's moons, which have the potential ingredients for life, the option to conduct a controlled crash was preferred.
In completing its final plunge, Cassini is going to a place where no man-made object has ever been before. Sleep well, little dude.
The Milky Way's fastest stars could have escaped from nearby galaxies
At the very edge of our galaxy, some stars are moving fast enough that they have the energy needed to escape its gravitational clutches. Now, it turns out, ours might not be the first galaxy these stars have escaped from.
Previously, physicists thought these incredibly fast stars were accelerated to such great speeds by the supermassive black hole at the centre of our galaxy.
But a new study shows these 'runaway' stars at the edge of the Milky Way were thrown our way from another nearby galaxy.
Researchers used computer simulations to show where these stars, known as hypervelocity stars, come from. The answer was the Large Magellanic Cloud (LMC), a dwarf galaxy in orbit around the Milky Way.
"Earlier explanations for the origin of hypervelocity stars did not satisfy me," said Douglas Boubert, a PhD student at Cambridge University and the paper's lead author. "The hypervelocity stars are mostly found in the Leo and Sextans constellations - we wondered why that is the case."
So far 20 hypervelocity stars are known, and most have been spotted in the northern hemisphere. Astronomers first thought hypervelocity stars were chucked out from the centre of the Milky Way, by a supermassive black hole. But if this was the case, the stars would be evenly distributed across the sky.
The new explanation solves this problem.
"These stars have just jumped from an express train - no wonder they're fast," said co-author Rob Izzard, a Rutherford fellow at the Institute of Astronomy. "This also explains their position in the sky, because the fastest runaways are ejected along the orbit of the LMC towards the constellations of Leo and Sextans."
The paper also predicts many more will be found. "We are the first to simulate the ejection of runaway stars from the LMC - we predict that there are 10,000 runaways spread across the sky," said Boubert.
"They travel between the galaxies in our local group," Izzard told WIRED.
"Many will end up falling into other galaxies, others might travel for billions of years through the space between galaxies. An important point is that quite a lot of these stars will die before they reach another galaxy, so by the time they reach another galaxy you would have a mix of low-mass stars like the Sun along with white dwarfs, neutron stars and black holes."
Half of the simulated stars escaping the LMC are fast enough to escape the gravity of the Milky Way - and if the predictions are correct we could find out as soon as next year.
"We'll know soon enough whether we're right," said Boubert. "The European Space Agency's Gaia satellite will report data on billions of stars next year, and there should be a trail of hypervelocity stars across the sky between the Leo and Sextans constellations in the North and the LMC in the South."
If this turns out to be right, there may be many more. "You can't imagine that our place in the universe is particularly special, so you have to think this will have happened elsewhere," Izzard told WIRED. "One project I'm currently thinking about trying is to estimate what this cosmological 'rain' of hypervelocity stars looks like."
We're closer than ever to Planet Nine
In January 2016, a pair of astronomers published a paper that changed the direction of modern astronomy. The paper predicted the existence of another, huge planet lurking far beyond Neptune, in the most distant realms of our solar system.
The pair dubbed this mysterious planet Planet Nine. Some perceived this name as a snub to the planet Pluto, our old ‘ninth planet’, which one of these very astronomers had played a part in demoting to ‘dwarf planet’ status ten years previously. But aside from this, everyone was excited.
Since the publication of that paper, astronomers over the world have spent time searching both using telescopes and computational models for any sign of Planet Nine. Now, the most detailed prediction yet of Planet Nine’s orbit and influence on our solar system has been released.
Konstantin Batygin, a Caltech professor of planetary science and co-author of the original paper, decided it was time that paper got an update.
“There have been new detections of distant Kuiper belt objects since the publication of our original paper,” Batygin says. ”We now better understand how the expanded observational dataset shaped by the gravity of Planet Nine.”
Batygin and Alessandro Morbidelli, from the University of Côte d'Azur, developed an up to date computer simulation, which takes into account the latest observational data, in a new paper uploaded to the server arXiv.
The important result of this paper is that it defines the exact orbit and behaviour of Planet Nine, rather than the vague notion there is another planet lurking somewhere. This is defined by how it influences the orbits of other, smaller objects that exist beyond Neptune, called trans-Neptunian objects.
“Remember that over the last 170 years, there have been numerous authors that have proposed variants of trans-Neptunian planets,” Batygin says. “What separates each proposition is the data a given hypothesis aims to explain - in our case, the physical clustering of the distant orbits - and the dynamical mechanism through which the planet generates its observational signatures.”
The new paper describes this mechanism mathematically, Batygin says. “I’ve always tried to be explicit about the fact that what we are proposing is not just the existence of a planet. Rather, it is the existence of a planet that sculpts a specific orbital pattern through a rather distinct physical mechanism.”
The paper narrows down the hunt for the planet. “With our new understanding of how Planet Nine sculpts the observed patterns in the data, we have been able to zoom in on its true orbit further,” Batygin says.
The search is still on. At the end of last month Batygin and Mike Brown, co-author of the original paper and the man behind Pluto’s demise, spent five nights in Hawaii. They used the Mauna Kea Observatory, and were searching for signs of Planet Nine.
“We had a genuinely fantastic observational run with Mike,” Batygin says. “In total, we covered about ~20% of the sky that we need to cover and the weather was for the most part, in our favour.”
However, it may still be some time before this data is published. For now, we will have to wait and keep wondering.
“Frustratingly, we do not yet know if we found Planet Nine this time around. The data is still in the process of being processed and analysed, there is a lot of data. So nothing observational to share yet.”
Our first interstellar visitor
In November, the first planetary body to come to our solar system form somewhere else was discovered. The object, originally named A/2017 U1, was spotted on October 18 when it was already heading away from Earth. It had been closer to the Sun in September and passed within 15 million miles of Earth on October 15.
One of the most peculiar things about it was how fast it was moving. Covering 15.8 miles (25.5 km) each second, the super-fast space rock is so hot it almost looked red.
Breakthrough Listen decided to study the object, now named ‘Oumuamua, and didn’t find evidence for any alien activity.
Yuri Milner’s Breakthrough Listen project, dedicated to finding life outside our solar system, has set its next target; a mysterious object that has visited our solar system from far, far away.
Named ‘Oumuamua, the rocky body is thought to be a strange, elongated cigar shape. It’s exciting because of how fast it is moving, meaning it’s likely to have come to our solar system from another star.
"Researchers working on long-distance space transportation have previously suggested that a cigar or needle shape is the most likely architecture for an interstellar spacecraft," the Breakthrough Listen team wrote in an update. On Wednesday, the team will examine ‘Oumuamua using the Robert C. Byrd Green Bank Telescope, in Green Bank, West Virginia. The telescope will listen across four radio bands, from 1 to 12 GHz, in the hope of detecting whether the object is some kind of interstellar spacecraft or not.
The object, originally named A/2017 U1, was spotted on October 18 when it was already heading away from Earth. It had been closer to the Sun in September and passed within 15 million miles of Earth on October 15.
Now it is about twice the distance between the Earth and the Sun from us, or two astronomical units (AU), which is about 186 million miles (300 million km). Those at Breakthrough Listen still want to grab the opportunity while it’s relatively close, to try and find out more about the body.
The team said the telescope could detect a signal from a mobile phone at this distance, in under a minute.
“‘Oumuamua’s presence within our solar system affords Breakthrough Listen an opportunity to reach unprecedented sensitivities to possible artificial transmitters and demonstrate our ability to track nearby, fast-moving objects,” said Andrew Siemion, Director of Berkeley SETI Research Center and part of Breakthrough Listen. “Whether this object turns out to be artificial or natural, it’s a great target for Listen.”
The chances of it being something created by extra-terrestrial life are slim to none. “It’s not a spacecraft,” says Dr Michele Bannister, from Queen’s University Belfast. “It’s a planetesimal with a well-baked crust that looks a lot like the tiniest worlds in our outer Solar System: a bit redder than solar, about the size of the Gherkin skyscraper in London.”
“Based on its trajectory, it looks more like something adrift in the Galaxy than something specifically aimed toward anything in particular, and it’s shown no signs of propulsion,” says Dr Katherine Mack, from North Carolina State University. “All the current observations make it look like an elongated reddish rock.”
However, this does not mean the observations are pointless. “I’m very glad Breakthrough Listen is investigating how to tell if interstellar objects might be artificial,” says Professor Jason Wright, astronomer at Penn State University.
Because of the frequencies the team will be listening in, they could reveal more information about the amount of water ice on the object and what gases it is surrounded by.
“It’s always worthwhile to investigate,” says Mack. “It’s also possible that there could be some interesting data about the composition of the object obtained even if it is, as seems likely, a naturally occurring asteroid. And even if there’s only a tiny chance they could find some artificial signal, taking a little time to listen will definitely be worth the trouble.”
And others aren’t even convinced it is definitely from elsewhere. “Although its current trajectory implies that it will ultimately leave the solar system, it is not currently possible to firmly state that this object actually came from beyond the solar system,” says Rene Heller, from the Max Planck k Institute for Solar System Research.
He said many other explanations, such as close encounters with other comets or minor planets, could fling an object from the outer solar system into the hyperbolic orbit ‘Oumuamua is on, and eject it from the solar system. “That said, this provides even more motivation for rapid follow-up observations to determine its nature because 'Oumuamua will soon be out of sight.”