Illustration of the “Beacon” inflating from its canister after reaching orbit. The Mayak Project used the Russian version of Kickstarter called Boomstarter to fund the project. Credit: cosmomayak.ru / Mayak Project
Artist’s view of the proposed Mayak (Beacon) satellite fully unfurled and orbiting Earth. Credit: cosmomayak.ru / Mayak Project
We may soon look up and see a satellite brighter than the space station and even Venus gliding across the night sky if a Russian crowdfunding effort succeeds. An enthusiastic team of students from Moscow University of Mechanical Engineering are using Boomstarter, the Russian equivalent of Kickstarter, to raise the money needed to build and launch a pyramid-shaped satellite made of highly reflective material they’re calling Mayak, Russian for “Beacon”.
Young engineers at Moscow University explain the Mayak Project
To date they’ve collected more than $23,000 or 1.7 million rubles. Judging from the video, the team has built the canister that would hold the satellite (folded up inside) and performed a high-altitude test using a balloon. If funding is secured, Beacon is scheduled to launch on a Soyuz-2 rocket from the Baikonur Cosmodrome in the second quarter of this year.
Illustration of the “Beacon” inflating from its canister after reaching orbit. The Mayak Project used the Russian version of Kickstarter called Boomstarter to fund the project. Credit: cosmomayak.ru / Mayak Project
Once in orbit, Beacon will inflate into a pyramid with a surface area of 172 square feet (16 square meters). Made of reflective metallized film 20 times thinner than a human hair, the satellite is expected to become the brightest man-made object in orbit ever. That title is currently held by the International Space Station which can shine as brightly as magnitude -3 or about three times fainter than Venus. The brightest satellites, the Iridiums, can flare to magnitude -8 (as bright as the crescent moon) but only for a few seconds before fading back to invisibility. They form a “constellation” of some 66 satellites that provide data and voice communications.
A student at the Mayak Lab in Moscow describes the container used to hold the reflective “Beacon” satellite. Credit: cosmomayak.ru / Mayak Project
A concurrently-developed mobile app would allow users to know when Beacon would pass over a particular location. The students hope to achieve more than just track a bright, moving light across the sky. According to their website,the goal of the project is the “popularization of astronautics and space research in Russia, as well as improving the attractiveness of science and technology education among young people.” They want to show that almost anyone can build and send a spacecraft into orbit, not just corporations and governments.
Further, the students hope to test aerodynamic braking in the atmosphere and find out more about the density of air at orbital altitudes. Interested donors can give anywhere from 300 rubles (about $5) up 300,000 ($4,000). The more money, the more access you’ll have to the group and news of the satellite’s progress; the top donor will get invited to watch the launch on-site.
Liftoff! Moscow University students release the satellite on a test run. Credit: cosmomayak.ru / Mayak Project
Once finished with the Mayak Project, the team wants to built another version that uses that atmosphere for braking its speed and returning it — and future satellites — safely back to Earth without the need for retro-rockets.
I think all these goals are worthy, and I admire the students’ enthusiasm. I only hope that satellite launching doesn’t become so cheap and popular that we end up lighting up the night sky even further. What do you think?
Galaxy GN-z11 superimposed on an image from the GOODS-North survey. Credit: NASA/ESA/P. Oesch (Yale University)/G. Brammer (STScI)/P. van Dokkum (Yale University)/G. Illingworth (University of California, Santa Cruz)
Since it was first launched in 1990, the Hubble Space Telescope has provided people all over the world with breathtaking views of the Universe. Using its high-tech suite of instruments, Hubble has helped resolve some long-standing problems in astronomy, and helped to raise new questions. And always, its operators have been pushing it to the limit, hoping to gaze farther and farther into the great beyond and see what’s lurking there.
And as NASA announced with a recent press release, using the HST, an international team of astronomers just shattered the cosmic distance record by measuring the farthest galaxy ever seen in the universe. In so doing, they have not only looked deeper into the cosmos than ever before, but deeper into it’s past. And what they have seen could tell us much about the early Universe and its formation.
Due to the effects of special relativity, astronomers know that when they are viewing objects in deep space, they are seeing them as they were millions or even billions of years ago. Ergo, an objects that is located 13.4 billions of light-years away will appear to us as it was 13.4 billion years ago, when its light first began to make the trip to our little corner of the Universe.
An international team of scientists has used the Hubble Space Telescope to spectroscopically confirm the farthest galaxy to date. Credits: NASA/ESA/B. Robertson (University of California, Santa Cruz)/A. Feild (STScI)
This is precisely what the team of astronomers witnessed when they gazed upon GN-z11, a distant galaxy located in the direction of the constellation of Ursa Major. With this one galaxy, the team of astronomers – which includes scientists from Yale University, the Space Telescope Science Institute (STScI), and the University of California – were able to see what a galaxy in our Universe looked like just 400 million years after the Big Bang.
Prior to this, the most distant galaxy ever viewed by astronomers was located 13.2 billion light years away. Using the same spectroscopic techniques, the Hubble team confirmed that GN-z11 was nearly 200 million light years more distant. This was a big surprise, as it took astronomers into a region of the Universe that was thought to be unreachable using the Hubble Space Telescope.
In fact, astronomers did not suspect that they would be able to probe this deep into space and time without using Spitzer, or until the deployment the James Webb Space Telescope – which is scheduled to launch in October 2018. As Pascal Oesch of Yale University, the principal investigator of the study, explained:
“We’ve taken a major step back in time, beyond what we’d ever expected to be able to do with Hubble. We see GN-z11 at a time when the universe was only three percent of its current age. Hubble and Spitzer are already reaching into Webb territory.”
The Hubble Space Telescope in 1997, after its first servicing mission. Credit: NASA
In addition, the findings also have some implications for previous distance estimates. In the past, astronomers had estimated the distance of GN-z11 by relying on Hubble and Spitzer’s color imaging techniques. This time, they relied on Hubble’s Wide Field Camera 3 to spectroscopically measure the galaxies redshift for the first time. In so doing, they determined that GN-z11 was farther way than they thought, which could mean that some particularly bright galaxies who’s distanced have been measured using Hubble could also be farther away.
The results also reveal surprising new clues about the nature of the very early universe. For starters, the Hubble images (combined with data from Spitzer) showed that GN-z11 is 25 times smaller than the Milky Way is today, and has just one percent of our galaxy’s mass in stars. At the same time, it is forming stars at a rate that is 20 times greater than that of our own galaxy.
As Garth Illingworth – one of the team’s investigator’s from the University of California, Santa Cruz – explained:
“It’s amazing that a galaxy so massive existed only 200 million to 300 million years after the very first stars started to form. It takes really fast growth, producing stars at a huge rate, to have formed a galaxy that is a billion solar masses so soon. This new record will likely stand until the launch of the James Webb Space Telescope.”
Last, but not least, they provide a tantalizing clue as to what future missions – like the James Webb Space Telescope – will be finding. Once deployed, astronomers will likely be looking ever farther into space, and farther into the past. With every step, we are closing in on seeing what the very first galaxies that formed in our Universe looked like.
Recent images sent by NASA's New Horizons spacecraft show possible clouds floating over the frozen landscape including the streaky patch at right. Credit: NASA/JHUAPL/SwR
Recent images sent by NASA’s New Horizons spacecraft show possible clouds floating over the frozen landscape including the hazy streak right of center. Credit: NASA/JHUAPL/SwRI
I think we were all blown away when the New Horizons spacecraft looked back at Pluto’s dark side and returned the first photos of a surprisingly complex, layered atmosphere. Colorless nitrogen along with a small percentage of methane make up Pluto’s air. Layers of haze are likely created when the two gases react in sunlight to form tiny, soot-like particles called tholins. These can ultimately grow large enough to settle toward the surface and coat and color Pluto’s icy exterior.
Close up of the back side of Pluto taken by New Horizons shows multiple layers of haze in its mostly nitrogen atmosphere. Credit: NASA/JHUAPL/SwRI
Now it seems Pluto’s atmosphere is capable of doing even more — making clouds! In an e-mail exchange with New Scientist, Lowell Observatory astronomer Will Grundy discusses the possibility that streaks and small condensations within the hazes might be individual clouds. Grundy also tracked a feature as it passed over different parts of the Plutonian landscape below, strongly suggesting a cloud. If confirmed, they’d be the first-ever clouds seen on the dwarf planet, and a sign this small 1,473-mile-wide (2,370 km) orb possesses an even more complex atmosphere than imagined.
Faint arrows along Pluto’s limb point to possible clouds in a low altitude haze layer. More distinct possible clouds are arrowed at left. Credit: NASA/JHUAPL/SwRI15 minutes after its closest approach, New Horizons snapped this image of the smooth expanse of Sputnik Planum (right) flanked to the west (left) by rugged mountains up to 11,000 feet (3,500 meters) high, including the informally named Norgay Montes in the foreground and Hillary Montes on the skyline. The backlighting highlights more than a dozen layers of haze in Pluto’s tenuous but distended atmosphere. Credit: NASA/JHUAPL/SwRI
Given the onion-like layers of haze and potential clouds, perhaps we shouldn’t be surprise that it snows on Pluto. The New Horizons team announced the discovery this week of a chain of exotic snowcapped mountains stretching across the dark expanse of the informally named Cthulhu Regio. Cthulhu, pronounced kuh-THU-lu and named for a character in American horror writer H.P. Lovecraft’s books, stretches nearly halfway around Pluto’s equator, starting from the west of the vast nitrogen ice plain, Sputnik Planum. At 1,850 miles (3,000 km) long and 450 miles (750 km) wide, Cthulhu is a bit larger than the state of Alaska. But ever so much colder!
The upper slopes of Cthulhu’s highest peaks are coated with a bright material that contrasts sharply with the dark red color of the surrounding plains. Scientists think it’s methane ice condensed from Pluto’s atmosphere. The far right panel shows the distribution of methane ice on the surface. Credit: NASA/JHUAPL/SwRI
Cthulhu’s red color probably comes from a covering of dark tholins formed when methane interacts with sunlight. But new close-up images reveal that the region’s highest mountains appear coated with a much brighter material. Scientists think it’s methane, condensed as ice onto the peaks from Pluto’s atmosphere.
“That this material coats only the upper slopes of the peaks suggests methane ice may act like water in Earth’s atmosphere, condensing as frost at high altitude,” said John Stansberry, a New Horizons science team member.
Compositional data from the New Horizon’s Ralph/Multispectral Visible Imaging Camera (MVIC), shown in the right panel in the image above, shows that the location of the bright ice on the mountain peaks correlates almost exactly with the distribution of methane ice, shown in false color as purple.
New Horizons still has plenty of images stored on its hard drive, so we’re likely to see more clouds, frosty peaks and gosh-knows-what-else as the probe speeds ever deeper into space while returning daily postcards from its historic encounter.
Aquarius the "Water Bearer" is a large but faint constellation in the Southern sky. Credit: Stellarium
Welcome back to Constellation Friday! Today, we will be dealing with one of the best-known constellations, that “watery” asterism and section of the sky known as Aquarius. Cue the soundtrack from Hair!
In the 2nd century CE, Greek-Egyptian astronomer Claudius Ptolemaeus (aka. Ptolemy) compiled a list of all the-then known constellations. This work (known as the Almagest) would remain the definitive guide to astronomy and astrology for over a thousand years. Among the 48 constellations listed in this book was Aquarius, a constellation of the zodiac that stretches from the celestial equator to the southern hemisphere.
An artist's illustration of the MOM orbiter at Mars. Image: By Nesnad - Own work, GFDL, https://commons.wikimedia.org/w/index.php?curid=29435816
Science—like literature and the arts—helps nations cooperate together, even when they’re in conflict politically. The USA and Russia are in conflict over the Ukraine and Syria, yet both nations still cooperate when it comes to the International Space Station. With that in mind, it’s great to see other nations—in this case India—taking on a greater role in space exploration and sharing their scientific results.
India’s Mars Orbiter Mission (MOM) probe has been in orbit around Mars since September 2014, after being launched in November 2013. Though the Indian Space Research Organization (ISRO) has released plenty of pictures of the surface of Mars, they haven’t released any scientific data. Until now.
A beautiful full-disc image of Mars captured by MOM. Image: ISRO/MOM.
In September 2015, MOM’s orbit was adjusted to bring it to within 260 km of Mars’ surface, significantly closer to the surface than the usual 400 km altitude. This manoeuver allowed one of MOM’s six instruments, the Mars Exospheric Neutral Composition Analyzer (MENCA), to measure the atmospheric composition at different altitudes. The sensor measured carbon dioxide, oxygen, nitrogen and carbon monoxide to see how they were distributed at different altitudes.
MOM’s activity at Mars is important for a couple of reasons. Its results confirm the results of other probes that have studied Mars’ atmosphere. And confirmation is an important part of science. But there’s another reason why MOM is important, and this centres around the search for evidence of life on the Red Planet.
Methane is considered a marker for the presence of life. It’s not an absolute indicator that life is or was present, but it’s a good hint. One of MOM’s sensors is the Methane Sensor for Mars (MSM.) Methane has been detected in Mars’ atmosphere before, but these could have been spikes, and not a strong indicator of living processes. If MSM provides stronger data indicating a consistent methane presence, that would be very interesting.
Releasing these results is also vindication for ISRO. In 2008, ISRO released data from their lunar mission, Chandrayaan-1, showing the presence of water on the Moon. Those results, which were gathered with an instrument called Chandra’s Altitudinal Composition Explorer (CHACE) were rejected by several scientific publications, on the grounds that the results were contaminated. Only when they were confirmed by another of Chandrayaan-1’s instruments—the Moon Mineralogy Mapper (M3)—were the results accepted.
But MOM’s MENCA instrument is based on the CHACE instrument aboard Chandrayaan-1, so ISRO feels that MENCA’s success in the atmosphere at Mars vindicates CHACE’s results on the Moon. And rightly so.
You can read a blog post by Syed Maqbool Ahmed at the Planetary Society, where he talks about the success of MOM’s MENCA, and how it vindicates ISRO’s earlier results with CHACE that showed the presence of water on the Moon.
MOM is India’s first interplanetary mission, and is expected to last until its fuel runs out, which could take many years. India is the first Asian nation to make it to another planet, and the first of any nation to make it to Mars on their first attempt. Not bad for a mission that was initially considered to be only a technology demonstration mission.
A team of astronomers from UCLA searched for "technosignatures" in the Kepler field data. Credit and Copyright: Danielle Futselaar
Very recently, a team of scientists from the Commonwealth Scientific and Industrial Research Organization (CSIRO) achieved an historic first by being able to pinpoint the source of fast radio bursts (FRBs). With the help of observatories around the world, they determined that these radio signals originated in an elliptical galaxy 6 billion light years from Earth. But as it turns out, this feat has been followed by yet another historic first.
In all previous cases where FRBs were detected, they appeared to be one-off events, lasting for mere milliseconds. However, after running the data from a recent FRB through a supercomputer, a team of scientists at McGill University in Montreal have determined that in this instance, the signal was repeating in nature. This finding has some serious implications for the astronomical community, and is also considered by some to be proof of extra-terrestrial intelligence.
FRBs have puzzled astronomers since they were first detected in 2007. This event, known as the Lorimer Burst, lasted a mere five milliseconds and appeared to be coming from a location near the Large Magellanic Cloud, billions of light years away. Since that time, a total of 16 FRBs have been detected. And in all but this one case, the duration was extremely short and was not followed up by any additional bursts.
The NSF’s Arecibo Observatory, which is located in Puerto Rico, is the world largest radio telescope. Credit: NAIC
Because of their short duration and one-off nature, many scientists have reasoned that FRBs must be the result of cataclysmic events – such as a star going supernova or a neutron star collapsing into a black hole. However, after sifting through data obtained by the Arecibo radio telescope in Puerto Rico, a team of students from McGill University – led by PhD student Paul Scholz – determined that an FRB detected in 2012 did not conform to this pattern.
In an article published in Nature, Scholz and his associates describe how this particular signal – FRB 121102 – was followed by several bursts with properties that were consistent with the original signal. Running the data which was gathered in May and June through a supercomputer at the McGill High Performance Computing Center, they determined that FRB 121102 had emitted a total of 10 new bursts after its initial detection.
This would seem to indicate that FRBs have more than just one cause, which presents some rather interesting possibilities. As Paul Scholz told Universe Today via email:
“All previous Fast Radio Bursts have only been one-time events, so a lot of explanations for them have involved a cataclysmic event that destroys the source of the bursts, such as a neutron star collapsing into a black hole. Our discovery of repeating bursts from FRB 121102 shows that the source cannot have been destroyed and it must have been due to a phenomenon that can repeat, such as bright pulses from a rotating neutron star.”
The Parkes Telescope in New South Wales, Australia. Credit: Roger Ressmeyer/Corbis
Another possibility which is making the rounds is that this signal is not natural in origin. Since their discovery, FRBs and other “transient signals” – i.e. seemingly random and temporary signals – from the Universe have been the subject of speculation. As would be expected, there have been some who have suggested that they might be the long sought-after proof that extra-terrestrial civilizations exist.
For example, in 1967, after receiving a strange reading from a radio array in a Cambridge field, astrophysicist Jocelyn Bell Burnell and her team considered the possibility that what they were seeing was an alien message. This would later be shown to be incorrect – it was, in fact, the first discovery of a pulsar. However, the possibility these signals are alien in origin has remained fixed in the public (and scientific) imagination.
This has certainly been the case since the discovery of FRBs. In an article published by New Scientistsin April of 2015 – titled “Cosmic Radio Plays An Alien Tune” – writer and astrophysicist Sarah Scoles explores the possibility of whether or not the strange regularity of some FRBs that appeared to be coming from within the Milky Way could be seen as evidence of alien intelligence.
However, the likelihood that these signals are being sent by extra-terrestrials is quite low. For one, FRBs are not an effective way to send a message. As Dr. Maura McLaughlin of West Virginia University – who was part of the first FRB discovery – has explained, it takes a lot of energy to make a signal that spreads across lots of frequencies (which is a distinguishing feature of FRBs).
For decades, scientists have been exploring the possibility that radio bursts are signals from alien civilizations. Credit: AdamBurn/DeviantArt
And if these bursts came from outside of our galaxy, which certainly seems to be the case, they would have to be incredibly energetic to get this far. As Dr. McLaughlin explained to Universe Today via email:
“The total amount of power required to produce just one FRB pulse is as much as the Sun produces in a month! Although we might expect extraterrestrial civilizations to send short-duration signals, sending a signal over the very wide radio bandwidths over which FRBs are detected would require an improbably immense amount of energy. We expect that extraterrestrial civilizations would transmit over a very narrow range of radio frequencies, much like a radio station on Earth.
But regardless of whether these signals are natural or extra-terrestrial in origin, they do present some rather exciting possibilities for astronomical research and our knowledge of the Universe. Moving forward, Scholz and his team hope to identify the galaxy where the radio bursts originated, and plans to use test out some recently-developed techniques in the process.
“Next we would like to localize the source of the bursts to identify the galaxy that they are coming from,” he said. “This will let us know about the environment around the source. To do this, we need to use radio interferometry to get a precise enough sky location. But, to do this we need to detect a burst while we are looking at the source with such a radio telescope array. Since the source is not always bursting we will have to wait until we get a detection of a burst while we are looking with radio interferometry. So, if we’re patient, eventually we should be able to pinpoint the galaxy that the bursts are coming from.”
In the end, we may find that rapid burst radio waves are a more common occurrence than we thought. In all likelihood, they are being regularly emitted by rare and powerful stellar objects, ones which we’ve only begun to notice. As for the other possibility? Well, we’re not saying it’s aliens, but we’re quite sure others will be!
Illustris simulation, showing the distribution of dark matter in 350 million by 300,000 light years. Galaxies are shown as high-density white dots (left) and as normal, baryonic matter (right). Credit: Markus Haider/Illustris
Mapping the Universe with satellites and ground-based observatories have not only provided scientists with a pretty good understanding of its structure, but also of its composition. And for some time now, they have been working with a model that states that the Universe consists of 4.9% “normal” matter (i.e. that which we can see), 26.8% “dark matter” (that which we can’t), and 68.3% “dark energy”.
From what they have observed, scientists have also concluded that the normal matter in the Universe is concentrated in web-like filaments, which make up about 20% of the Universe by volume. But a recent study performed by the Institute of Astro- and Particle Physics at the University of Innsbruck in Austria has found that a surprising amount of normal matter may live in the voids, and that black holes may have deposited it there.
In a paper submitted to the Royal Astronomical Society, Dr. Haider and his team described how they performed measurements of the mass and volume of the Universe’s filamentary structures to get a better idea of where the Universe’s mass is located. To do this, they used data from the Illustris project – a large computer simulation of the evolution and formation of galaxies.
The Big Bang Theory: A history of the Universe starting from a singularity and expanding ever since. Credit: grandunificationtheory.com
As an ongoing research project run by an international collaboration of scientists (and using supercomputers from around the world), Illustris has created the most detailed simulations of our Universe to date. Beginning with conditions roughly 300,000 years after the Big Bang, these simulations track how gravity and the flow of matter changed the structure of the cosmos up to the present day, roughly 13.8 billion years later.
The process begins with the supercomputers simulating a cube of space in the universe, which measures some 350 million light years on each side. Both normal and dark matter are dealt with, particularly the gravitational effect that dark matter has on normal matter. Using this data, Haider and his team noticed something very interesting about the distribution of matter in the cosmos.
Essentially, they found that about 50% of the total mass of the Universe is compressed into a volume of 0.2%, consisting of the galaxies we see. A further 44% is located in the enveloping filaments, consisting of gas particles and dust. The remaining 6% is located in the empty spaces that fall between them (aka. the voids), which make up 80% of the Universe.
However, a surprising faction of this normal matter (20%) appears to have been transported there, apparently by the supermassive black holes located at the center of galaxies. The method for this delivery appears to be in how black holes convert some of the matter that regularly falls towards them into energy, which is then delivered to the sounding gas, leading to large outflows of matter.
Artist’s impression of a supermassive black holes at the hearts of a galaxy. Credit: NASA/JPL-Caltech
These outflows stretch for hundreds of thousands of lights years beyond the host galaxy, filling the void with invisible mass. As Dr. Haider explains, these conclusions supported by this data are rather startling. “This simulation,” he said, “one of the most sophisticated ever run, suggests that the black holes at the center of every galaxy are helping to send matter into the loneliest places in the universe. What we want to do now is refine our model, and confirm these initial findings.”
The findings are also significant because they just may offer an explanation to the so-called “missing baryon problem”. In short, this problem describes how there is an apparent discrepancy between our current cosmological models and the amount of normal matter we can see in the Universe. Even when dark matter and dark energy are factored in, half of the remaining 4.9% of the Universe’s normal matter still remains unaccounted for.
For decades, scientists have been working to find this “missing matter”, and several suggestions have been made as to where it might be hiding. For instance, in 2011, a team of students at the Monash School of Physics in Australia confirming that some of it was in the form of low-density, high energy matter that could only be observed in the x-ray wavelength.
In 2012, using data from the Chandra X-ray Observatory, a NASA research team reported that our galaxy, and the nearby Large and Small Magellanic Clouds, were surrounded by an enormous halo of hot gas that was invisible at normal wavelengths. These findings indicated that all galaxies may be surrounded by mass that, while not visible to the naked eye, is nevertheless detectable using current methods.
And just days ago, researchers from the Commonwealth Scientific and Industrial Research Organization (CSIRO) described how they had used fast radio bursts (FRBs) to measure the density of cosmic baryons in the intergalactic medium – which yielded results that seem to indicate that our current cosmological models are correct.
Factor in all the mass that is apparently being delivered to the void by supermassive black holes, and it could be that we finally have a complete inventory of all the normal matter of the Universe. This is certainly an exciting prospect, as it means that one of the greatest cosmological mysteries of our time could finally be solved.
Now if we could just account for the “abnormal” matter in the Universe, and all that dark energy, we’d be in business!
The globular cluster Messier 5, one of the oldest belonging to the Milky Way. Credit: NASA/ESA/HST
In the late 18th century, Charles Messier was busy hunting for comets in the night sky, and noticed several “nebulous” objects. After initially mistaking them for the comets he was seeking, he began to compile a list of these objects so other astronomers would not make the same mistake. Known as the Messier Catalog, this list consists of 100 objects, consisting of distant galaxies, nebulae, and star clusters.
Among the many famous objects in this catalog is the M5 globular star cluster (aka. NGC 5904). Located in the galactic halo within the Serpens Constellation, this cluster of stars is almost as old as the Universe itself (13 billion years)! Though very distant from Earth and hard to spot, it is a favorite amongst amateur astronomers who swear by its beauty.
Researchers at the CSIRO have managed to pinpoint the location of an FRB for the first time, yielding valuable information about our universe. Credit: csiro.au
In July of 2012, researchers at the CERN laboratory made history when they announced the discovery of the Higgs Boson. Though its existence had been hypothesized for over half a century, confirming its existence was a major boon for scientists. In discovering this one particle, the researchers were also able to confirm the Standard Model of particle physics. Much the same is true of our current cosmological model.
For decades, scientists been going by the theory that the Universe consists of about 70% dark energy, 25% dark matter and 5% “luminous matter” – i.e. the matter we can see. But even when all the visible matter is added up, there is a discrepancy where much of it is still considered “missing”. But thanks to the efforts of a team from the Commonwealth Scientific and Industrial Research Organization (CSIRO), scientists now know that we have it right.
This began on April 18th, 2015, when the CSIRO’s Parkes Observatory in Australia detected a fast radio burst (FRB) coming from space. An international alert was immediately issued, and within a few hours, telescopes all around the world were looking for the signal. The CSIRO team began tracking it as well with the Australian Telescope Compact Array (ATCA) located at the Paul Wild Observatory (north of Parkes).
Image showing the field of view of the Parkes radio telescope (left) and zoom-ins on the area where the signal came from (left). Credit: D. Kaplan (UWM), E. F. Keane (SKAO).
With the help of the National Astronomical Observatory of Japan’s (NAOJ) Subaru telescope in Hawaii, they were able to pinpoint where the signal was coming from. As the CSIRO team described in a paper submitted to Nature, they identified the source, which was an elliptical galaxy located 6 billion light years from Earth.
This was an historic accomplishment, since pinpointing the source of FRBs have never before been possible. Not only do the signals last mere milliseconds, but they are also subject to dispersion – i.e. a delay caused by how much material they pass through. And while FRBs have been detected in the past, the teams tracking them have only been able to obtain measurements of the dispersion, but never the signal’s redshift.
Redshift occurs as a result of an object moving away at relativistic speeds (a portion of the speed of light). For decades, scientists have been using it to determine how fast other galaxies are moving away from our own, and hence the rate of expansion of the Universe. Relying on optical data obtained by the Subaru telescope, the CSIRO team was able to obtain both the dispersion and the redshift data from this signal.
As stated in their paper, this information yielded a “direct measurement of the cosmic density of ionized baryons in the intergalactic medium”. Or, as Dr. Simon Johnston – of the CSIRO’s Astronomy and Space Science division and the co-author of the study – explains, the team was not only to locate the source of the signal, but also obtain measurements which confirmed the distribution of matter in the Universe.
“Until now, the dispersion measure is all we had,” he said. “By also having a distance we can now measure how dense the material is between the point of origin and Earth, and compare that with the current model of the distribution of matter in the Universe. Essentially this lets us weigh the Universe, or at least the normal matter it contains.”
Dr. Evan Keane of the SKA Organization, and lead author on the paper, was similarly enthused about the team’s discovery. “[W]e have found the missing matter,” he said. “It’s the first time a fast radio burst has been used to conduct a cosmological measurement.”
As already noted, FRB signals are quite rare, and only 16 have been detected in the past. Most of these were found by sifting through data months or years after the signal was detected, by which time it would be impossible for any follow-up observations. To address this, Dr. Keane and his team developed a system to detect FRBs and immediately alert other telescopes, so that the source could be pinpointed.
Artists impression of the SKA-mid dishes in Africa shows how they may eventually look when completed. Credit: skatelescope.org
It is known as the Square Kilometer Array (SKA), an international effort led by the SKA Organization to build the world’s largest radio telescope. Combining extreme sensitivity, resolution and a wide field of view, the SKA is expected to trace many FRBs to their host galaxies. In so doing, it is hoped the array will provide more measurements confirming the distribution of matter in the Universe, as well as more information on dark energy.
In the end, these and other discoveries by the SKA could have far-reaching consequences. Knowing the distribution of matter in the universe, and improving our understanding of dark matter (and perhaps even dark energy) could go a long way towards developing a Theory Of Everything (TOE). And knowing how all the fundamental forces of our universe interact will go a long way to finally knowing with certainty how it came to be.
These are exciting time indeed. With every step, we are peeling back the layers of our universe!
