Radio telescope image of the galaxy 4C12.50, nearly 1.5 billion light-years from Earth. Inset shows detail of location at end of superfast jet of particles, where a massive gas cloud (yellow-orange) is being pushed by the jet.
(Credit: Morganti et al., NRAO/AUI/NSF)
It’s long been a mystery for astronomers: why aren’t galaxies bigger? What regulates their rates of star formation and keeps them from just becoming even more chock-full-of-stars than they already are? Now, using a worldwide network of radio telescopes, researchers have observed one of the processes that was on the short list of suspects: one supermassive black hole’s jets are plowing huge amounts of potential star-stuff clear out of its galaxy.
Astronomers have theorized that many galaxies should be more massive and have more stars than is actually the case. Scientists proposed two major mechanisms that would slow or halt the process of mass growth and star formation — violent stellar winds from bursts of star formation and pushback from the jets powered by the galaxy’s central, supermassive black hole.
“With the finely-detailed images provided by an intercontinental combination of radio telescopes, we have been able to see massive clumps of cold gas being pushed away from the galaxy’s center by the black-hole-powered jets,” said Raffaella Morganti, of the Netherlands Institute for Radio Astronomy and the University of Groningen.
The scientists studied a galaxy called 4C12.50, nearly 1.5 billion light-years from Earth. They chose this galaxy because it is at a stage where the black-hole “engine” that produces the jets is just turning on. As the black hole, a concentration of mass so dense that not even light can escape, pulls material toward it, the material forms a swirling disk surrounding the black hole. Processes in the disk tap the tremendous gravitational energy of the black hole to propel material outward from the poles of the disk.
NGC 253, aka the Sculptor Galaxy, is also blowing out gas but as the result of star formation (Image: T.A. Rector/University of Alaska Anchorage, T. Abbott and NOAO/AURA/NSF)
At the ends of both jets, the researchers found clumps of hydrogen gas moving outward from the galaxy at 1,000 kilometers per second. One of the clouds has much as 16,000 times the mass of the Sun, while the other contains 140,000 times the mass of the Sun.
The larger cloud, the scientists said, is roughly 160 by 190 light-years in size.
“This is the most definitive evidence yet for an interaction between the swift-moving jet of such a galaxy and a dense interstellar gas cloud,” Morganti said. “We believe we are seeing in action the process by which an active, central engine can remove gas — the raw material for star formation — from a young galaxy,” she added.
The researchers published their findings in the September 6 issue of the journal Science.
A close conjunction of Venus and the crescent Moon as seen on February 27th, 2009. (Photo by author).
Sky watchers worldwide are in for a treat Sunday evening September 8, 2013 as the waxing crescent Moon passes near the dazzling planet Venus. And for a select few, the Moon will actually pass in front of Venus, in what is known as an occultation.
The action has already started this week, as the Moon reached New phase earlier today at 7:36 AM EDT/11:36 UT. The appearance of the slim crescent Moon nearest to the September equinox marks the start of the Jewish New Year with the celebration of Rosh Hashanah, which this year began as early as it possibly can at sundown on September 4th. As per tradition, Rosh Hashanah formally begins when the sky is dark enough for three stars to be seen. The convention established by Hillel II in 363 A.D. uses the mean motion of the Moon to fix the start dates of the Jewish luni-solar calendar, which means that occasionally Rosh Hashanah can start a day early. This also occurred in 2002.
The New Moon has also been historically an opportune time for nighttime military operations to commence —Desert Storm in 1991 and the raid against Bin Laden in 2011 were both conducted under the darkness afforded by the absence of moonlight around a New Moon. It’s yet to be seen if planners looking to conduct airstrikes on Syria are planning on taking advantage of the same conditions to begin operations soon.
Tonight, you can see the +1st magnitude star Spica less than two degrees away from -4th magnitude Venus. This places Venus at 100 times brighter than Spica and visible before sunset if you know exactly where to look for it.
The brightest star in the constellation Virgo, Spica is 260 light years distant and on the short list of nearby stars that will eventually go supernova. Fortunately for us, Spica is well outside of the ~100 light year radius “kill zone”.
You might just be able to spy the Moon and the -1st magnitude planet Mercury low to the west at dusk for the first time for this lunation tonight or (more likely) Friday night. This is also a great time to check out LADEE’s future home as it departs for lunar orbit from Wallops Island in Virginia on Friday night.
Hey, LADEE sitting on the pad atop its Minotaur V rocket with the slim crescent Moon in the background at dusk Friday night would be a great money shot, I’m just sayin’…
This weekend will see the Moon increase in illumination and elevation above the western horizon each evening until Spica, Venus, and the waxing crescent Moon fit within a four degree circle on Sunday night. The Moon will be 12% illuminated, while Venus is currently at a gibbous phase and 72% lit.
Looking west from latitude 30 north Sunday night from the US east coast… note that Mercury and Saturn are in the picture as well! (Created by the author in Stellarium).
This will also present a good chance to see Venus during the daytime, using the nearby crescent Moon as a guide. This is a fun thing to try, and no gear is required! Though Venus may seem tough to find against the bright daytime sky, appearances are deceptive. With an albedo of 67% versus the Moon’s average of 14% Venus is actually brighter than the Moon per square arc second of size!
The Moon will also occult Spica on the evening of September 8th for observers in the Middle East and Europe right around sunset. Spica is one of four bright stars that the Moon can occult in the current epoch, along with Antares, Aldebaran, and Regulus. This is also part of a series of fine occultations of Spica by the Moon ongoing from 2012 to 2014.
Sundown on September 8th offers a special treat, as the 3-day old Moon passes less than a degree from Venus worldwide. The pair will fit easily into the field of view of binoculars or a telescope at low power and present an outstanding photo op.
And for observers based in Argentina and Chile, the Moon will actually occult Venus. Occultations are grand events, a split-second astronomical event in a universe that seems to usually move at a glacial pace. This particular occultation occurs for South American observers just before & after sunset.
The occultation of Venus by the Moon; the footprint over South America. (Credit: Occult 4.1.0.2).
We witnessed and recorded a similar pairing of Venus and the daytime Moon from the shores of our camp on Saint Froid Lake in northern Maine back in 2007:
Also, keep an eye out for a ghostly phenomenon known as the ashen light on the dark limb of the Moon. Also known as Earthshine, what you’re seeing is the reflection of sunlight off of the Earth illuminating the (cue Pink Floyd) dark side of the Moon. When the Moon is a crescent as seen from the Earth, the Earth is at gibbous phase as seen from the nearside of the Moon. Remember, the lunar farside and darkside are two different things! Earthshine can vary in brightness, based on the amount of cloud and snow cover present or absent on the Earth’s moonward side. My Farmer’s Almanac-consulting grandpappy would call ashen light the “Old Moon in the New Moon’s arms,” and reckon rain was a comin’…
Be sure to check out these astronomical goings on this weekend, and send those pics in to Universe Today!
I love science fiction films and I especially love it when the “science” part leans closer to fact than fiction. (Yes, I’m looking at you, Europa Report.) Now I’ve never seen an actual catastrophe in orbit (and I hope I never do) but I have to assume it’d look a whole lot like what’s happening in the upcoming film “Gravity,” opening in U.S. theaters on October 4. This full official trailer was released today.
A disaster film sure becomes a whole lot more interesting when everything is moving 18,000 miles an hour and there’s no up or down. And, of course, space. (!!!)
The Kirobo talking robot on the ISS. Credit: Toyota.
The talking robot launched to the International Space Station in August has sent its first audio/visual message to Earth. Kirobo, the mini Japanese robot — which appears to have the bravado of Buzz Lightyear and the cuteness of WALL-E — is just .34 meters (13.4-inches) long. Kirobo is designed to be able to have conversations with its astronaut crewmates and to study how robot-human interactions can help the astronauts in the space environment. In its first message, Kirobo wished Earth a “good morning” and mentioned (and motioned) its giant step in getting to space.
Kirobo is part of a research project sponsored by the University of Tokoyo and Toyota, and the robot will be working closely with Koichi Wakata, slated to be the first Japanese commander of the ISS for Expedition 39, who will launch this November as part of the Expedition 38/39 crew. An identical robot named Mirata remains on Earth for additional testing.
Kirobo is designed to navigate in zero-gravity, have facial recognition of its fellow crewmates, and will assist Wakata in various experiments. No word on whether it will have access to opening or closing the various hatches on the space station.
Our Universe is big, and it’s been around for a long time. So why don’t we see any evidence of aliens? If they are out there, why haven’t they contacted us, and how do we contact them? What methods might they use to try and contact us?
Where do we look for signs of alien civilizations?
The search for extraterrestrial intelligence, otherwise known as SETI, are the methods that scientists have proposed to discover evidence of aliens in the Universe.
Perhaps the most famous method is listening for their signals. Here on Earth, we have exploited the radio spectrum to send signals through the air. We even use it to communicate with spacecraft in the Solar System.
So, since it works so well for us, it makes sense that aliens might use radio waves to communicate from star to star. If there’s an alien civilization out there beaming a signal directly at the Sun, our largest radio telescopes should be able to pick up their signal.
The problem is that the galaxy is huge, with hundreds of billions of stars. Any one of which could be the world where the aliens live. Furthermore, we don’t know which frequency the aliens might use to communicate with us.
Even though the search for ET has been going for many years, we’ve only explored a fraction of the millions of available stars and frequencies on the radio spectrum.
So far, no definitive signal has been discovered.
Gieren et al. used the 8.2-m Very Large Telescope (Yepun) to image M33, and deduce the distance to that galaxy (image credit: ESO).Another possibility is that aliens are using lasers to communicate with us. An alien could target an incredibly powerful laser at our star, and it would be detectable with our large optical telescopes. There have been a few dedicated searches for laser communication, and scientists have proposed we could search for these alien signals at the same time we’re searching for extrasolar planets.
Again, so far nothing has turned up.
View from inside the Borexino neutrino detector. Image Credit: Borexino CollaborationIt’s possible that aliens use a more exotic method of communication, like neutrinos.
Neutrinos are generated in high energy collisions, and can pass right through planets with ease. They would be incredibly difficult to detect with our current technology, but maybe advances in the future will make that a possible communication method.
But maybe Instead of searching for signals, we could look for their artifacts.
If the energy of transmitting signals across the vast reaches of space is too much, it might make more sense for aliens to construct self-replicating probes and let them journey from star to star.
These probes could leave behind an obvious alien-made structure which we could discover once we become a true spacefaring species.
We could also detect aliens by their impact on their home planets. With a large enough space telescope, we should be able to study the atmosphere of planets orbiting nearby stars. An industrialized civilization would probably be polluting its atmosphere with various gases — just like we have — which would be detectable.
Finally, we could search for evidence of aliens through their structures.
If a civilization starts building megastructures which block off a large portion of their star’s light, we should be able to detect evidence through our search for extrasolar planets.
A Star Trek-inspired space station.A gigantic space station would give off a much different light signature than a nice spherical planet as it passes in front of its star.
There have been a few attempts to reach out to other worlds directly, transmitting signals out into space. It’s unlikely that these signals will actually reach any other civilization, and some scientists are concerned about the wisdom of this kind of communication.
Do we really want to alert potentially hostile aliens to our location in the Milky Way?
It’s exciting to think that there are other alien civilizations around us in the Milky Way, and with a little more work, we could discover their location and maybe even communicate with them.
The process of selecting a site for NASA's next landing on Mars, planned for September 2016, has narrowed to four semifinalist sites located close together in the Elysium Planitia region of Mars. The mission known by the acronym InSight will study the Red Planet's interior, rather than surface features, to advance understanding of the processes that formed and shaped the rocky planets of the inner solar system, including Earth. Image credit: NASA/JPL-Caltech
Where’s the best place to drill baby, drill on Mars – and not for oil but digging into Mars’ past? Apparently, a relatively level spot near the equator is the preferred spot. The 2016 InSight lander is the next mission to land on Mars and it will use a probe to hammer down 3-5 meters under the surface. NASA has now narrowed down the potential landing sites to just four from an original twenty-two proposed locations, and all four lie along the planet’s mid-section on the plains of Elysium Planitia.
“We picked four sites that look safest,” said geologist Matt Golombek from the Jet Propulsion Laboratory. Golombek is leading the site-selection process for InSight. “They have mostly smooth terrain, few rocks and very little slope.”
This artist’s concept depicts the stationary NASA Mars lander known by the acronym InSight at work studying the interior of Mars. Image credit: JPL/NASA
InSight stands for “Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport” and it is scheduled to launch in March 2016 and land in September of that year. The mission will investigate processes that formed and shaped Mars and will help scientists better understand the evolution of our inner solar system’s rocky planets, including Earth. It will also monitor the planet’s current internal temperature and any seismology taking place.
So, unlike previous Mars landings, what is on the surface in the area matters little in the choice of a site except for safety considerations.
“This mission’s science goals are not related to any specific location on Mars because we’re studying the planet as a whole, down to its core,” said Bruce Banerdt, InSight principal investigator. “Mission safety and survival are what drive our criteria for a landing site.”
Elysium works well for the InSight mission because of two basic engineering constraints. One requirement is being close enough to the equator for the lander’s solar array to have adequate power at all times of the year. Also, the elevation must be low enough to have sufficient atmosphere above the site for a safe landing. The spacecraft will use the atmosphere for deceleration during descent.
InSight also needs penetrable ground for its probe that will monitor heat coming from the planet’s interior. This tool can penetrate through broken-up surface material or soil, but could be foiled by solid bedrock or large rocks. InSight also will deploy a seismometer on the surface and will use its radio for scientific measurements.
Images from the Mars Reconnaissance orbiter have been crucial in narrowing down the sites, and will continue to aid scientists and engineers in choosing the final site.
Golombek said that since considering what is below the surface is important to evaluate candidate landing sites, scientists also studied MRO images of large rocks near Martian craters formed by asteroid impacts. Impacts excavate rocks from the subsurface, so by looking in the area surrounding craters, the scientists could tell if the subsurface would have probe-blocking rocks lurking beneath the soil surface.
Each semifinalist site is an ellipse measuring 81 miles (130 kilometers) from east to west and 17 miles (27 kilometers) from north to south. Engineers calculate the spacecraft will have a 99-percent chance of landing within that ellipse, if targeted for the center.
The team will select two or three finalists by the end of 2014, and make a final decision on InSight’s destination by the end of 2015.
Minotaur V rocket launch view as should be seen from atop the Empire State Building, NY, on Sept. 6, 2013 at 11:12 p.m. EDT - weather permitting.
Minotaur V rocket and LADEE spacecraft launch trajectory view as should be seen from atop the Empire State Building, NY, on Sept. 6, 2013 at 11:27 p.m. EDT – weather permitting. See more launch trajectory viewing graphics below[/caption]
WALLOPS ISLAND, VA – An unprecedented spectacle is set to light up the skies this Friday night, Sept. 6, courtesy of NASA when America returns to the Moon with the history making nighttime launch of the LADEE lunar orbiter atop a retired and specially converted intercontinental ballistic missile (ICBM) from NASA’s Wallops Island facility on the Virginia shoreline.
Blastoff of NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) Observatory atop the maiden flight of the powerful new Minotaur V rocket is slated for 11:27 p.m. EDT Sept. 6 from Launch Pad 0B along the Eastern Shore of Virginia at NASA Wallops.
Because it’s at night and lifting off from the most densely populated region of the United States, the flames spewing from the tail of Minotaur could be visible to tens of millions of distant spectators – weather permitting – who have never before witnessed such a rocket launch.
So you don’t have to be watching locally to join in the fun and excitement. And you can always watch the NASA TV webcast online on a smartphone or laptop.
Minotaur V rocket launch view as should be seen from Wright Brothers Memorial, Kitty Hawk, NC
The LADEE (pronounced ‘laddie’ not ‘lady’) launch is historic in many ways.
So although the very best views are available from local areas in Virginia, Maryland and Delaware just tens of miles away from the Wallops Island launch pad, magnificent viewing opportunities are available from a broad region up and down the East Coast and into the interior.
Let’s look at some viewing maps courtesy of Orbital Sciences, the company responsible for assembling the Minotaur V and integrating it with the LADEE spacecraft – built by NASA’s Ames Research Center.
First up is the Maximum elevation map showing how high the rocket will be visible in degrees from the heavily populated US East Coast stretching from Maine to both Carolinas and into the industrial Midwest.
LADEE Minotaur V Launch – Maximum Elevation Map
The LADEE nighttime launch will be visible to millions of spectators across a wide area of the Eastern US -weather permitting. This map shows the maximum elevation (degrees above the horizon) that the Minotaur V rocket will reach during the Sep. 6, 2013 launch depending on your location along the US east coast. Credit: Orbital Sciences
Herein are a series of graphics showing the Minotaur V trajectory and what you should see – during firings of the first three stages – from the perspective of standing on the ground or skyscrapers at a variety of popular destinations including the US Capitol, Lincoln Memorial, Kitty Hawk, NC, Atlantic City, NJ, New York City, Cape Cod and more.
US CapitolCape Cod, MALincoln MemorialNew York City (Battery Park)
The five stage Minotaur V rocket stands 80.6 feet (24.6 meters) tall, is 7.6 feet (2.3 m) in diameter and weighs 197,034 pounds (89,373 kilograms.
The first three stages of the Minotaur V are based on the nuclear armed Peacekeeper ICBM intercontinental ballistic missile built during the Cold War – now retired and refurbished by Orbital for peaceful uses. It’s literally beating swords into plowshares.
The 5th stage is a new addition and what makes this Minotaur a new rocket class. The added thrust is precisely what enables shooting for the Moon.
Minotaur V rocket launch view as should be seen from Atlantic City, NJ
For anyone coming to the Wallops area for an eyewitness view of the launch, NASA worked with local officials to establish several viewing locations just 10 miles or so from the launch pad at the Mid-Atlantic Regional Spaceport, at NASA’s Wallops Flight Facility, Wallops Island, Va.
Visitors to the area may view the launch from Robert Reed Park on Chincoteague or Beach Road spanning the area between Chincoteague and Assateague Islands.
Both sites will feature a live countdown and broadcast and NASA personnel will be on hand to discuss the LADEE launch and goals of the mission.
A big-screen projector will broadcast live in Robert Reed Park beginning at 9:30 p.m.
“We’re excited about this partnership with the community in providing an enhanced launch experience to members of the public,” said Jeremy Eggers, public information officer for NASA Wallops in a statement. “The live countdown and launch broadcast will place people in mission control on launch night for what is already a historic mission for Wallops and the Eastern Shore.”
NASA TV starts a live broadcast of the launch at 9:30 p.m. on Sept 6 – available here: http://www.nasa.gov/ntv
Minotaur V rocket with NASA’s LADEE lunar orbiter unveiled at NASA Wallops launch pad. Credit: NASA EDGE/Franklin Fitzgerald
The couch sized 844 pound (383 kg) robotic explorer is equipped with 3 science instruments and a laser technology demonstrator.
These include an ultraviolet and visible light spectrometer that will gather detailed information about the composition of the tenuous lunar atmosphere; a neutral mass spectrometer to measure variations in the lunar atmosphere over time; a laser dust experiment that will collect and analyze dust particle samples; and a laser communications experiment that will test the use of lasers in place of radio waves for high speed data communications with Earth.
Be sure to watch for my continuing LADEE and Antares launch reports from on site at NASA’s Wallops Launch Pads in sunny Virginia – reporting for Universe Today.
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Learn more about LADEE, Cygnus, Antares, MAVEN, Orion, Mars rovers and more at Ken’s upcoming presentations
Sep 5/6/16/17: “LADEE Lunar & Antares/Cygnus ISS Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA
Oct 3: “Curiosity, MAVEN and the Search for Life on Mars – (3-D)”, STAR Astronomy Club, Brookdale Community College & Monmouth Museum, Lincroft, NJ, 8 PM
Oct 8: “LADEE Lunar & Antares/Cygnus ISS Rocket Launches from Virginia”; Princeton University, Amateur Astronomers Assoc of Princeton (AAAP), Princeton, NJ, 8 PM
LADEE’s Ticket to the Moon – 5th Stage of new Minotaur V rocket
Close-up view of STAR 37 5th stage solid fuel motor for inaugural Minotaur V rocket launch at NASA Wallops rocket facility will propel LADEE into its lunar transfer orbit. LADEE will be mounted on top and surrounded by the payload fairing attached at bottom ring. Credit: Ken Kremer/kenkremer.com
This image of comet ISON C/2012 S1 from NASA’s Deep Impact/EPOXI spacecraft clearly shows the coma and nucleus on Jan. 17 and 18, 2013 beyond the orbit of Jupiter. Credit: NASA.
Disappointing news today from Dr. Mike A’Hearn, Principal Investigator of the EPOXI mission, which has been using the repurposed spacecraft from the Deep Impact mission to study comets. The spacecraft was going to take some much-anticipated images of Comet ISON, but apparently a communication problem has occurred and the images may have been lost or possibly never taken.
“We have not received any of our expected observations of comet ISON due to a spacecraft problem,” A’Hearn wrote in an update on the EXPOXI website. “Communication with the spacecraft was lost some time between August 11 and August 14 (we only talk to the spacecraft about once per week). The last communication was on August 8. After considerable effort, the team on August 30 determined the cause of the problem. The team is now trying to determine how best to try to recover communication.”
No additional information was provided about the cause of the problem, however.
The Deep Impact mission intentionally crashed an impactor into comet Tempel-1 on July 4, 2005. Since then, EPOXI — the name comes from two combined missions to re-use the observing spacecraft, the Extrasolar Planet Observations and Characterization (EPOCh) and the Deep Impact Extended Investigation (DIXI) — has gone on to study comet Hartley 2, performing a close fly-by in 2010, studied C/2009 P1 (Garradd) in 2012, and has continued to be used as a remote observatory for studying comets.
EPOXI took images of Comet ISON on January 17, 2013, showing that the comet’s brightness varied on a timescale of hours (see the video above). There was another observing window from mid-February to March 8, where the team took infrared images of the comet.
The additional observing window from early July to early September is the timeframe for which there was a communication problem, and A’Hearn didn’t specify if any early images were received from the spacecraft, although he said they had “not received any of our expected observations.”
We’ll provide more information when it becomes available.
Landing on asteroids will be a risky endeavor, perhaps aggravated by changes in asteroid dust when it's touched. Credit: NASA Near Earth Object Program
NASA is really getting into this crowd-sourcing thing. The space agency asked and the public responded with hundreds of ideas of what missions could be done with asteroids in regards to protecting Earth from these space rocks and finding an asteroid humans can explore. NASA received over 400 responses to their “Asteroid Initiative Request For Information” request, hearing from the space industry, universities, and the general public.
Now, after looking at all the responses, NASA has chosen 96 ideas it regards as most promising, ranging from asteroid observation plans to asteroid redirection, deflection or capture systems, to creating crowd sourcing and citizen science opportunities.
Next, NASA will host an Asteroid Initiative Idea Synthesis Workshop where NASA personnel and the space community will discuss and further these 96 ideas to narrow them down even further to help with its planning activities and future missions.
The 96 ideas were chosen by a team of NASA scientists, engineers, and mission planners who evaluated the proposed ideas. The evaluation team rated the responses for relevance to the RFI objectives, innovativeness of the idea, maturity of the development approach, and potential to improve mission affordability.
This is the first time NASA has used this type of crowd-sourcing and discussion method to look at possible future missions.
NASA said the ideas proposed “provide the agency with fresh insight into how best to identify, capture and relocate a near-Earth asteroid for closer study and respond to asteroid threats.” Ideas included pointers on how to decrease an asteroid’s spin, nudge it away from a path toward Earth, take samples to return to Earth and create activities to heighten public awareness of not only the threat asteroids pose, but the valuable resources and scientific benefits they may offer.
“This rich set of innovative ideas gathered from all over the world provides us with a great deal of information to factor into our plans moving forward,” said Robert Lightfoot, Associate Administrator for NASA. “We’re making great progress on formulating this mission, and we look forward to discussing further the responses we received to the RFI.”
The upcoming public workshop will be held on Sept. 30 – Oct. 2 and onsite participation is limited to just the presenters, but it appears the workshop will be webcast (more info later), as NASA said they will release information on virtual participation options as the workshop nears.
Artist's conception of GJ 1214 b passing across its host star, as viewed in blue light. Credit: NAOJ
Playing with the filters on a telescope can show us amazing things. In a recent case, Japanese astronomers looked at the star Gilese 1214 in blue light and watched its “super-Earth” planet (Gliese 1214 b, or GJ 1214 b) passing across the surface from the viewpoint of Earth. The result — a probable detection of water in the planet’s atmosphere.
Observations with the Subaru Telescope using a blue filter revealed the atmosphere does not preferentially scatter any light. If the Rayleigh scattering had been observed, this would have shown hydrogen in the atmosphere, researchers said. (On Earth, Rayleigh scattering of the atmosphere makes the sky blue.)
“When combined with the findings of previous observations in other colors, this new observational result implies that GJ 1214 b is likely to have a water-rich atmosphere,” stated the National Astronomical Observatory of Japan.
The planet is an ideal candidate for exoplanet observations because it is relatively close to Earth (40 light years away) and is about 2.7 times the size of our planet, allowing for possible comparisons between the worlds.
Three images showing the relationship between the atmosphere’s composition and the transmitted colors of light. Top: Hydrogen-dominated atmospheres see much of the blue light scattered, meaning that transits become more visible in blue light than red light. Middle: Atmospheres with less hydrogen scatter blue wavelengths more weakly. Bottom: Cloud-covered planets make it more difficult for light to make its way up through the atmosphere, even if the atmosphere is dominated by hydrogen. Credit: NAOJ
There’s still some debate over whether “super-Earths” are closer in nature to Earth or to Uranus or Neptune (each about four times Earth’s diameter), requiring scientists to scrutinize that class of exoplanets to learn more about their properties.
One area under investigation is where the super-Earths form. It is believed that planets arise out of a protoplanetary disk, or cloud of gas, ice and debris that surrounds a young star at the beginning of its life. Hydrogen is a big part of this disk, as well as water ice beyond the “snow line“, or the region in a planetary system where waning heat makes it possible for ice to form.
“Findings about where super-Earths have formed and how they have migrated to their current orbits point to the prediction that hydrogen or water vapor is a major atmospheric component of a super-Earth,” NAOJ stated. “If scientists can determine the major atmospheric component of a super-Earth, they can then infer the planet’s birthplace and formation history.”
The team acknowledges it’s still possible there is hydrogen in GJ 1214 b’s atmosphere, but add their findings do corroborate with past ones suggesting water.
