Elizabeth Howell is the senior writer at Universe Today. She also works for Space.com, Space Exploration Network, the NASA Lunar Science Institute, NASA Astrobiology Magazine and LiveScience, among others. Career highlights include watching three shuttle launches, and going on a two-week simulated Mars expedition in rural Utah. You can follow her on Twitter @howellspace or contact her at her website.
Artist's impression of 624 Hektor, the largest known Trojan asteroid. The dual asteroid is 155 miles (250 kilometers) at its widest. It also has a 7.5-mile (12-mile) moon. Credit: H. Marchis/F. Marchis
Two icy asteroids could have crashed into each other early in the solar system’s history to form the strange-looking 624 Hektor, new research reveals. The 155-mile (250-kilometer) asteroid is the largest known Trojan asteroid, or space rock that follows along with Jupiter in the gas giant’s orbital path.
Hektor also has a moon, which was first discovered in 2006 by another team led by the same lead author, the SETI Institute’s Franck Marchis. It’s taken the astronomers about eight years to get a handle on the complex orbit of the system, a topic that the new research examines in detail. That was partly because the path was so “bizarre”, the team stated, and also because time on the W.M. Keck Observatory telescopes (used to perform the observations) is limited. There are few other observatories that could do the same work, the team added.
The moon, which is about 7.5 miles or 12 kilometers in diameter, orbits its parent asteroid every three days. The moon’s path is about 373 miles (600 km) distant and inclined almost at 45 degrees to the asteroid’s equator.
The Trojan asteroid 624 Hektor is visible in these two adaptive optics observations in July 2006 and October 2008, both performed with the W.M. Keck Observatory’s II telescope. Hektor is in the middle of each picture, and its moon in the circles. Credit: WMKO/Marchis
“The orbit of the moon is elliptical and tilted relative to the spin of Hektor, which is very different from other asteroids with satellites seen in the main-belt,” stated Matija Cuk, a paper co-author who is a scientist at the Carl Sagan Center of the SETI Institute. “However, we did computer simulations, which include Hektor being a spinning football shape asteroid and orbiting the Sun, and we found that the moon’s orbit is stable over billions of years.”
While the artist’s conception above shows Hektor as a peanut, the exact shape is still not known for sure. The models and the adaptive optics suggest that it is likely a dual-lobe asteroid. What is better known, however, is that the asteroid is “extremely elongated” and spins in less than seven hours.
The origin of the moon is unclear, but the researchers suggested it could be because of ejecta associated with the collision that formed the asteroid. They said more simulations are needed on that point. What’s more, Hektor has another mystery associated with its composition.
An artist’s rendering of a Kuiper Belt object. Image: NASA
“We also show that Hektor could be made of a mixture of rock and ices, similar to the composition of Kuiper belt objects, Triton and Pluto. How Hektor became a Trojan asteroid, located at only 5 times the Earth–Sun distance, is probably related to the large scale reshuffling that occurred when the giant planets were still migrating,” stated Julie Castillo-Rogez, a researcher at NASA’s Jet Propulsion Laboratory who participated in the research.
You can read more about the research in Astrophysical Journal Letters. By the way, the moon does not have a name yet, and the researchers said they are looking for any ideas as long as it fulfills a couple of ideas: “the satellite should receive a name closely related to the name of the primary and reflecting the relative sizes between these objects.” Feel free to share your suggestions in the comments.
A scanning electron microscope image of a small section of a meteorite found evidence of past water in a Martian meteorite (specifically, in the form of tunnels and microtunnels). The meteorite is called
Yamato 000593. The rock was originally recovered in Antarctica in 2000 and is believed to have come from Mars. Credit: NASA
Could this meteorite show evidence of ancient water and life on Mars? That’s one possibility raised in a new paper led by NASA and including members of a team who made a contentious claim about Martian microfossils in another meteorite 18 years ago.
“This is no smoking gun,” stated lead author Lauren White, who is based at NASA’s Jet Propulsion Laboratory, of the findings released this week. “We can never eliminate the possibility of contamination in any meteorite. But these features are nonetheless interesting and show that further studies of these meteorites should continue.”
The new, peer-reviewed work focuses on tunnels and microtunnels the scientists said they found in a meteorite called Yamato 00593. The meteorite is about 30 pounds (13.7 kilograms) and was discovered in Antarctica in 2000. The structures were found deep within the rock, NASA stated, and “suggest biological processes might have been at work on Mars hundreds of millions of years ago.”
Scientists believe the 1.3-billion-year-old rock left Mars about 12 million years ago after an impact threw it off the surface. It reached Antarctica 50,000 years ago and after it was found in 2000, was analyzed and believed to be a “nakhlite”, or a kind of Martian meteorite. “Martian meteoritic material is distinguished from other meteorites and materials from Earth and the moon by the composition of the oxygen atoms within the silicate minerals and trapped Martian atmospheric gases,” NASA stated.
An asteroid impacts ancient Mars and send rocks hurtling to space – some reach Earth
There are two things in the meteorite that caught the attention of scientists. One is the aforementioned tunnels and microtunnels, which they say are similar to those altered by bacteria in basalt on Earth. The second is tiny, carbon-enriched spherules (in the nanometer to micrometer range) between layers in the rock — structures similar to another Martian meteorite (Nakhla) that struck Egypt in 1911. In that case, the rock was recovered quickly after landing and still had the same spherules, the researchers noted.
The authors said it’s possible that these structures could be explained by other mechanisms besides life, but said the similarities to what they have found on Earth “imply the intriguing possibility that the Martian features were formed by biotic activity.”
The research team includes NASA’s David McKay (who died a year ago), Everett Gibson and Kathie Thomas-Keptra. In 1996, these same scientists (then led by McKay) found “biogenic evidence” in a meteorite called Allen Hills 84001, but other science teams have disagreed with the findings. There have been a lot of papers about this particular meteorite, and you can read more about the controversy in this 2011 Universe Today article.
NASA astronaut Chris Cassidy examines a spacesuit during Expedition 36 in August 2013. Credit: NASA
Astronauts on the International Space Station “could have ignited flammable materials” on station while drying out a spacesuit that experienced a major leak during a spacewalk in July 2013, a new report reveals.
NASA Mission Control directed the Expedition 36 crew to use a vacuum cleaner to suction out the water, a procedure that inadvertently sucked up oxygen from the suit’s secondary high pressure oxygen tank, says a mishap report into the spacesuit leak incident. This “potentially hazardous risk” of electricity and pure oxygen created a fire hazard, the report added.
In a phone call with reporters yesterday (Feb. 27), report chair Chris Hansen added that the “levels of oxygen were perfectly safe” in this particular incident and that the “the risk to the crew in the end was none”, but said the incident still warranted attention in the 222-page report, which mainly deals with the spacesuit leak.
The incident occurred on July 17, 2013, one day after a “life-threatening” amount of water leaked into a spacesuit helmet used by Luca Parmitano, the report said. The astronauts and NASA were doing looking for the source of the leak. Astronauts reported no damage to the water bag and no water in the suit (which had been cleaned up after the spacewalk).
Parts of a NASA spacesuit used on board the International Space Station, as cited in a February 2014 report about a spacesuit leak the previous July. Credit: NASA
Next, they turned on the fan to the portable life support system (or backpack) with a secondary oxygen pack (SOP) check-out fixture. The fixture covered a vent port and oxygen switch for about 14 minutes. All appeared to be running normally, with no water detected. When the crew then removed the fixture (following procedure), they heard a “sucking” noise and the fan ceased moving, the report said.
“The crew was directed to turn off the suit fan and move the O2 Actuator to OFF. The crew then turned the suit fan back ON and again set the O2 Actuator to [the] IV [setting]. The fan briefly began spinning and then shut down almost immediately, with the crew reporting a water “sucking” or “gurgling” sound,” the report added.
The crew found “a few drops” of water in a canister outlet and “about a spoonful” of water in the suit inlet ports, as well as a few drops of water in a neck vent port. As the ground decided what to do, an infrared carbon-dioxide transducer in the suit “began to show an increase in its reading and eventually went off-scale high, most likely due to moisture in the vent loop near the CO2 [carbon dioxide] transducer,” the report stated.
Italian astronaut Luca Parmitano during a spacesuit fit check before his mission. Credit: NASA
With water in the suit, Mission Control then asked the crew to remove the water with a vacuum (one that is designed for wet or dry cleanup) as soon as the astronauts had the chance. Everything was normal until after the station emerged from a routine loss of signal, at which point controllers saw the secondary oxygen pack was turned on and reading 500 pounds per square inch lower than before the loss of communication.
“They quickly realized that their procedure had resulted in the EMU releasing 100% oxygen from the SOP into the vent loop, which was then sucked into the vacuum cleaner. This was a potentially dangerous situation involving unintended consequences,” the report said.
ISS Astronauts had to scramble to get Luca Parmitano out of his spacesuit after water leaked inside the suit, covering his face. Via NASA TV.
“During interviews, system experts indicated that they should have been able to anticipate SOP activation due to the reduced pressure created by the vacuum cleaner. The procedure was immediately stopped. No fire occurred and the crew was not harmed.”
In interviews after the incident, individuals spoke of “perceived pressure” to do the dry-out procedure quickly instead of first testing it on the ground with similar hardware. They instead used a non-functional spacesuit before directing the crew to do the procedure.
There were at least three factors contributing to that pressure, the report added: the desire to avoid corrosion in the suit, limited crew time, and the impending loss of signal.
The report did not identify any “additional causes, findings, or observations” from this event, noting that it is not technically an anomaly and was not classified as such in the NASA literature.
Luca Parmitano during a a spacewalk on July 16, 2013. An hour into the spacewalk, he reported water in his helmet and NASA cut the spacewalk short. Credit: NASA
While NASA’s Mission Control “performed admirably” during a spacewalk water leak crisis in July, a report on the incident showed that controllers did not send astronaut Luca Parmitano back to the airlock until after he made three calls saying the water didn’t appear to be from a drinking bag.
There are several reasons this happened, the mishap report says, such as inadequate training, the crew members and ground misunderstanding the severity of the situation, and a (false) perception that any water leak is likely due to a problem with the drinking bag.
Another big problem was the “normalization of deviance”, similar language to what was used during in reports describing the Challenger and Columbia incidents. In this case, small amounts of water in the helmet was expected, and controllers also misunderstood the cause of a carbon dioxide alarm (a fairly regular occurrence during spacewalks).
The report pulls no punches when it describes how bad things were: “The presence of this water created a condition that was life threatening.”
While talking about what is in the report, it’s also important to point out what the investigators did not find. There was no evidence that contractors were afraid to bring up problems (such as what happened during the 1986 Challenger explosion), chair Chris Hanson told reporters yesterday. Also, while the suits are 35 years old, no aging problem was detected.
Another couple of cautions: the report is preliminary (the exact cause of the leak is under investigation), it’s lengthy (222 pages) and much of the technical information is unavailable to the public due to export control restrictions. Any news story will just scratch the surface of what happened and the recommendations to fix it.
That said, here are a few key points we found in the report.
European Space Agency astronaut Luca Parmitano on a spacewalk July 9, 2013 during Expedition 36. Here, Parmitano is riding the end of the robotic Canadarm2. Credit: NASA
Parmitano warned controllers multiple times. The transcript shows three separate calls from Parmitano saying it wasn’t the drinking bag at cause: (1) “I feel a lot of water on the back of my head, but I don’t think it is from my bag.” (2) “The leak is not from the water bag and it is increasing.” (3) “I’m thinking that it might not be the water bag.” (In between 1 and 2, he also sent another call saying his “only guess” was it was the drinking bag, but the report adds that Parmitano may have softened his stance after speaking to controllers). Misunderstanding about the severity, lack of training, “cognitive overload” of controllers, and space-to-ground-to-space communication difficulties are all cited as contributing factors.
Drink bags don’t actually leak as much as people think they did. Unequivocally, the mishap investigation board says “the perception that drink bags leak, especially as a frequent occurrence, is false.” There has never been an instance of a bag leaking substantially during a spacewalk, the report says. After the crisis passed and investigators had the luxury of time, they in fact identified seven separate possible sources of water: (1) the bag; (2) the waste collection garment; (3) cooling water from the sublimator heat rejection component of the suit; (4) the Liquid Cooling Ventilation Garment connector or the tubing itself; (5) transfer lines through the Hard Upper Torso; (6) water storage tankage through the pressurizing bladders; (7) the water separator circuit (which is where the problem was eventually found).
It was a risky decision to send Parmitano back alone. Twenty-three minutes after Parmitano warned of water in his helmet, NASA terminated the spacewalk and as per procedure, had the astronaut head to the airlock while crewmate Chris Cassidy performed cleanup tasks before doing the same. (“Terminate” has a specific meaning as opposed to “abort”, which means both crew members leave immediately.) By this time, water was in Parmitano’s eyes and the station had passed into the shadow of the Earth, forcing him to feel his way back to the airlock along the tether. (This was only his second spacewalk on station, too.) Also, the water affected his communications equipment, as he made several calls “in the blind” that were not heard. At this time, Cassidy and the ground controllers did not know how severe the situation was. “Additional risk exposure that the team could have considered was the aspiration of water, failure of comm equipment, and impaired visibility,” the report said.
European Space Agency astronaut Luca Parmitano does spacesuit maintenance prior to July 9 and 16, 2013 spacewalks. Parmitano was a member of Expeditions 36 and 37. Credit: NASA
The emphasis on science on station can hinder with maintenance tasks. NASA and other space station partners are eager to demonstrate how great the station is to science, but crew time is divided between that and doing maintenance tasks. “Due to this knowledge, team members felt that requesting on-orbit time for anything non-science related was likely to be denied and therefore tended to assume their next course of action could not include on-orbit time,” the report states. To give a specific example of how this affected Parmitano’s suit: After water was found in the suit during a previous spacewalk, the crew and ground essentially determined it was due to the drink bag and did not probe further, partly because of the perception that doing an investigation would take an inordinate amount of time for little return (as they believed they knew the cause). On a related note, there was also the concern that investigating this occurrence (which happened on July 9) would delay the July 16 spacewalk. (Again, this sounds a bit like Challenger, where time pressure was cited as a reason to launch despite icy conditions.)
More needs to be done to understand the physics of water in a spacesuit. A few examples: it was believed the fan would have failed if water got through the separator unit, which did not occur. It was also believed that any water in the helmet would cling to the helmet, and not the crew member’s face. Not only that, the training for crew and ground was inadequate to seek out water causes on the fly. “Had this been done, the crew and ground team may not have attributed water in the helmet to just the drink bag,” the report stated.
Water in the helmet was normalized. If you’ve read Chris Hadfield’s An Astronaut’s Guide to Life On Earth, there’s an account in there about how Hadfield (who also was a junior spacewalker in 2001) became temporarily blind due to an anti-fog agent on the helmet getting into his eyes. This has happened during other spacewalks, too, which meant that the ground team was used to small amounts of water in the helmet — even though this wasn’t a normal condition. Another aspect: a carbon dioxide alarm went off in Parmitano’s suit after it became saturated with water. This happened six minutes before he felt the dampness. The team attributed this to “nominal accumulation of moisture in the vent loop,” which can happen at the end of the spacewalk. Having it happen less than an hour in, however, did not trigger a fault-finding process.
Water collecting inside of a spacesuit helmet. This was the lead image in a report investigating a July 2013 water leak in a spacesuit used by European Space Agency astronaut Luca Parmitano. Credit: NASA
While there are many, many causes in the report (with aspects ranging from the technical to the procedural to the training), members identified three main ones to the incident: (1) inorganic materials in the water separator drum holes, for reasons still unknown (2) a lack of understanding that meant the team’s response took longer than usual (3) a misdiagnosis of the water found during the July 9, 2013 spacewalk.
There are 49 separate recommendations ranging from “Level 1” priority to “Level 3”, which are still important but less urgent. NASA has pledged it will clear all “Level 1” and “Level 2” items before doing any normal spacewalks, although contingency ones are still possible. They expect this to be finished by June, but say they will take as long as needed to get the investigation done. There are no pressing spacewalk tasks on station right now.
Looking to the long run, the report noted that there should be more backups available if a fault is found in the spacesuits, as NASA is relying on these devices to perform essential station maintenance as far as 2028. Also, the investigators say that the six-year certification of these suits for orbital tasks is likely inadequate, and calls for a review of that. So although aging was not identified as an issue, maintenance and backups of the spacesuits could be key features of NASA thinking in the months and years to come.
Self-portrait of Expedition 36/37 European Space Agency astronaut Luca Parmitano during a July 2013 spacewalk. Credit: NASA
It took NASA almost the same amount of time as a sitcom episode to send Luca Parmitano back to the airlock when the Italian astronaut experienced a leak in his spacesuit last summer, a new report reveals.
The 23-minute gap of time between when Parmitano first sent a report of water in his helmet, to when NASA told him to go back to safety, exposed the astronaut “to an increased level of risk”, the report said. While Parmitano emerged from the incident safely, in his last minutes inside the spacesuit the water was covering his eyes, getting close to his nose and mouth, and affecting the communications equipment.
“There wasn’t an issue of anything being hidden or surprised. It was a lack of understanding about the severity of the event. It was believed a drink bag caused the leak,” said Chris Hansen, the chair of the mishap investigation board, in a press conference today (Feb. 26).
This misunderstanding, added Hansen (who is also the chief engineer of the International Space Station Program) also led to a problem when a leak occurred in the same suit just the week before.
Parmitano’s water leak occurred July 16 when he and Chris Cassidy were preparing a part of the International Space Station for a new Russian module. Until today, however, few knew about the existence of a second leak in the same spacesuit that happened on July 9, when Cassidy and Parmitano were doing another spacewalk together.
Astronaut Chris Cassidy works with Luca Parmitano’s spacesuit, which had a water leak on July 16, 2013. Credit: NASA
After the conclusion of “EVA 22” on July 9, as NASA called the extra-vehicular activity, Parmitano took off his helmet and crew members discovered between 0.5 and 1 liters (0.13 to 0.26 gallons) of water inside. Cassidy told the ground that he could not see any water during the spacewalk or repressurization, leading NASA to conclude the water got into the helmet in the airlock.
“Also,” the report noted, “[Parmitano] was looking down and leaning forward and likely had pressed on the drink bag with his chest and could have pinched the bite valve open with his chin, releasing water into his helmet. The ground team accepted the crew’s drink bag leak assessment and the presence of excessive water in the helmet was not investigated further … The ground team instructed the crew to use a new drink bag for the upcoming EVA 23, which they did.”
Hanson emphasized that the crew did not make the final call, and that the ground team did ask some questions about what was going on, but the assumption that a drink bag caused the water was also a key feature of the July 16 spacewalk when the leak began to show itself in earnest.
ISS Astronauts had to scramble to get Luca Parmitano out of his spacesuit after water leaked inside the suit, covering his face. Via NASA TV.
Also, NASA did not well understand the physics of how water worked inside of the suit, assuming there was no way for liquid to make it past a fan pump separator into the helmet unless the fan itself shut off. If that scenario arose, NASA would have kicked into a 30-minute return-to-airlock procedure, and that was in the back of controllers’ minds as they were working through the fault tree during the July 16 spacewalk, officials said in the phone call today.
In the short term, the authors of the report have several “Level 1” or priority recommendations that they should be implemented before normal spacewalks resume. NASA said it’s planning to work through these and “Level 2” recommendations in time for June, with the aim of getting spacewalks going again in July or August.
NASA astronaut Mike Hopkins holds a spare ammonia pump module during a spacewalk Dec. 24, 2013. Hopkins and fellow Expedition 38 Rick Mastracchio (top) performed two spacewalks to replace a pump blamed for crippling one of the International Space Station’s two cooling loops Dec. 11. Credit: NASA TV (screenshot)
Emergency spacewalks can still go forward, as the agency has new safety measures in place (including snorkels). This happened in December as the astronauts replaced a faulty ammonia pump.
The agency has no pressing spacewalk tasks at this time. The broken pump, sitting in temporary stowage outside the station, was initially safed to stay there until summer, but further analysis shows that it could sit there for several months more.
You can read the entire 222-page report here. We’ll pull out more highlights tomorrow after we have some time to look over it in more detail, too. The exact cause of the leak is still under investigation.
Meet Kepler-22b, an exoplanet with an Earth-like radius in the habitable zone of its host star. Unfortunately its mass remains unknown. Image Credit: NASA
Planet-watchers, some exciting news: you know how we keep talking about planet candidates, those planets that have yet to be confirmed, when we reveal stories about other worlds? That’s because verifying that the slight dimming of a star’s light is due to a planet takes time – -specifically, to have other telescopes verify it through examining gravitational wobbles on the parent star.
Turns out there’s a way to solve the so-called “bottleneck” of planet candidates vs. confirmed planets. NASA has made use of a new technique that they say will work for multi-planet systems, one that already has results: a single Kepler release of data today (Feb. 26) yielded 715 new planets in one shot. That almost doubles the amount of known planets found before today, which was just under 1,000, officials said.
“This is the largest windfall of planets, not exoplanet candidates, but actual verified exoplanets announced at one time,” said Doug Hudgins, a NASA exoplanet exploration program scientist based in Washington, D.C., at a press conference today. What’s more, among the release were four planets (about double to 2.5 times the size of Earth) that could be considered habitable: Kepler-174 d, Kepler-296 f, Kepler-298 d, Kepler-309 c.
The findings were based on scouring the first two of Kepler’s four years of data, so scientists expect there will be a lot more to come once they go through the second half. Most of the discoveries were planets close to Earth’s size, showing that small planets are common in multiplanetary systems.
These planets, however, are crowded into insanely compact multiple planet systems, sometimes within the reaches of the equivalent of Mercury’s or Venus’ orbits. It’s raising questions about how young systems would have enough material in those reaches to form planets. Perhaps planetary migration played a role, but that’s still poorly understood.
Verification by multiplicity is a new method for finding planets in multiple-planet systems. In cases where astronomers see several objects transiting a star in regular orbits, the assumption is it must be planets. A set of stars in a similar configuration would have orbits too unstable for regular transits. Credit: NASA
Discoveries of these worlds was made with a new technique called “verification by multiplicity”. The challenge with the method Kepler uses — watching for starlight dimming when a planet passes in front of it — is there are other ways that same phenomenon can occur. One common reason is if the star being observed is a binary star and the second star is just barely grazing the first.
This is how the technique works: If you can imagine a star with a bunch of other stars around it, the mutual gravities of each object would throw their relative orbits into chaos. A star with a bunch of planets, however, would have a more stable orbital configuration. So if scientists see multiple transits of objects across a star’s face, the assumption is that it would be several planets.
“This physical difference, the fact you can’t have multiple star systems that look like planetary systems, is the basis of the validation by multiplicity,” said Jack Lissauer, a planetary scientist at the NASA Ames Research Center who was involved in the research.
Although this is a new technique, the astronomers said there has been at least one published publication talking about this method, and they added that two papers based on their own research have been accepted for publication in the peer-reviewed Astrophysical Journal.
Sizes of verified planets just after a release of 715 confirmed planets from Kepler data in February 2014. Credit: NASA
There’s been a lot of attention on Kepler lately, not only because of its planetary finds, but also its uncertain status. In May 2013, a second of its four reaction wheels (or gyroscopes) went down, robbing the probe of its primary mission: to seek planets transiting in front of their stars in a spot in the Cygnus constellation. Since then, scientists have been working on a new method of finding planets with the spacecraft.
The spacecraft is good to go for K2 physically, NASA added, as the spacecraft only has four major malfunctions: the two reaction wheels, and 2 (out of 21) “science modules” that are used for science observing. The first module failed early in the mission, while the second died during a recent K2 test. While the investigation is ongoing, NASA said that they expect it will be due to an isolated part failure and that it will have no measurable impact on doing K2.
Edit, 8:30 p.m. EST: The two papers related to the Kepler discovery are available here and here on the prepublishing site Arxiv. Both are accepted for publication in the Astrophysical Journal. (Hat tip to Tom Barclay).
Multi-wavelength view of the elliptical galaxy NGC 5044. Credit: Digitised Sky Survey/NASA Chandra/Southern Observatory for Astrophysical Research/Very Large Array (Robert Dunn et al. 2010)
Contradicting past theories, cold gas has been found in abundance in some elliptical galaxies — showing that there must be some other explanation why these types of galaxies don’t form new stars. Astronomers believe that the jets from supermassive black holes in these galaxies’ center must push around the gas and prevent stars from forming.
Researchers spotted the gas for the first time using old data from the recently retired Herschel space observatory, which was able to peer well into the infrared — where it spotted carbon ions and oxygen atoms. This find stands against the previous belief that these galaxies were “red and dead”, referring to their physical appearance and the fact that they form no new stars.
“We looked at eight giant elliptical galaxies that nobody had looked at with Herschel before and we were delighted to find that, contrary to previous belief, six out of eight abound with cold gas”, stated Norbert Werner, a researcher at Stanford University in California who led the study.
“These galaxies are red, but with the giant black holes pumping in their hearts, they are definitely not dead,” added Werner.
NGC 1399, an elliptical galaxy about 65 million light years from Earth. Credit: NASA, Chandra
Previously, scientists thought that the galaxies got rid of their cold gas or had used it all up during a burst of earlier star formation. With cold gas found in the majority of the sample, researchers then used other observatories to try to find warmer gas up to tens of millions of Kelvin (or Fahrenheit or Celsius).
X-ray information from NASA’s Chandra X-ray Observatory revealed that there is hot gas cooling in six of the eight galaxies, but not in the remaining two of the sample.
“This is consistent with theoretical expectations: once cooled, the hot gas would become the warm and cold gas that are observed at longer wavelengths. However, in these galaxies the cooling process somehow stopped, and the cold gas failed to condense and form stars,” the European Space Agency stated.
“While the six galaxies with plenty of cold gas harbour moderately active black holes at their centres,” ESA added, “the other two show a marked difference. In the two galaxies without cold gas, the central black holes are accreting matter at frenzied pace, as confirmed by radio observations showing powerful jets of highly energetic particles that stem from their cores.”
NASA's Solar Dynamics Observatory captured these images of a large flare erupting from the sun Feb. 21, 2014. Credit: NASA/SDO
She’s a rainbow! You can see the first moments of a huge flare belching off the sun in the picture above. The so-called X-class flare erupted a few hours ago (at 7:25 p.m. EST Feb. 24, or 12:25 a.m. UTC Feb. 25) and was captured by several spacecraft. If you have a pictures of the sun yourself to share, feel free to post them in the Universe Today Flickr pool.
NASA’s Solar Dynamics Observatory saw the flare growing in at least six different wavelengths of light, which are visible in the image above. This is classified this as an X4.9-class flare, which shows that it is pretty strong. X-flares are the most powerful kind that the sun emits, and each X number is supposed to be twice as intense as the previous one (so an X-2 flare is twice as powerful as X-1, for example).
SpaceWeather.com says this is the most powerful flare of the year so far, emitted from sunspot AR1967 (or more properly speaking, AR1990; sunspots are renamed if they survive a full rotation of the sun, as this one has done twice already!) While solar flares can lead to auroras, in this case it appears the blast was pointed in the wrong direction, the site added.
“Although this flare is impressive, its effects are mitigated by the location of the blast site–near the sun’s southeastern limb, and not facing Earth,” SpaceWeather stated. “Indeed, a bright coronal mass ejection (CME) which raced away from the sun shortly after the flare appears set to miss our planet.”
This image from the Solar and Heliospheric Observatory illustrates increased solar activity between Feb. 18-20, 2014. Credit: ESA/NASA/SOHO/GSFC
The sun goes through an 11-year cycle of sunspot and solar activity, which is supposed to be at its peak right now. This particular peak has been very muted, but lately things have been picking up. The European Space Agency noted that between Feb. 18 and 20, the sun sent out six CMEs in three days, with most of them moving in different directions.
“This level of activity is consistent with what we might expect as the Sun is near its maximum period of activity in the 11-year solar cycle,” ESA stated.
M33, the Triangulum Spiral Galaxy, seen here in a 4.3 hour exposure image. Astronomers used JWST to examine a section of its south spiral arm to search out and find nearly 800 newly forming stars. Credit and copyright: John Chumack.
We keep saying this: the universe is more complex than it appears. Conventional thinking in galaxy research postulates that spiral galaxies have star-forming areas, while ellipticals do not due to a lack of gas. While this thinking has been debunked, there’s now emerging research showing a “green valley” of galaxies somewhat in between these two types.
Basically, the research (which includes participation from citizen scientists in the Galaxy Zoo project) is showing that there are two different populations of “green” galaxies, between ellipticals and spirals. Further, what happens to star formation based upon gas in the area.
“In this paper, we take a look at the most crucial event in the life of a galaxy: the end of star formation. We often call this process ‘quenching’ and many astrophysicists have slightly different definitions of quenching. Galaxies are the place where cosmic gas condenses and, if it gets cold and dense enough, turns into stars. The resulting stars are what we really see as traditional optical astronomers,” wrote Kevin Schawinski, a Ph.D. student at the University of Oxford who is on the Galaxy Zoo team, in a blog post.
“Not all stars shine the same way though: stars much more massive than our sun are very bright and shine in a blue light as they are very hot. They’re also very short-lived. Lower mass stars take a more leisurely pace and don’t shine as bright (they’re not as hot). This is why star-forming galaxies are blue, and quiescent galaxies (or ‘quenched’ galaxies) are red: once star formation stops, the bluest stars die first and aren’t replaced with new ones, so they leave behind only the longer-lived red stars for us to observe as the galaxy passively evolves.”
Chelyabinsk fireball recorded by a dashcam from Kamensk-Uralsky north of Chelyabinsk where it was still dawn. A study of the area near this meteor air burst revealed similar signatures to the Tall el_Hammam site.
Looking at the power of the Chelyabinsk meteor (which struck a year ago and is visible starting around 1:15 in the video above) is still terrifying all these months later. Happily for those of on Earth worried about these big space rocks, the world’s space agencies are taking the threat seriously and are starting to implement new tracking systems to look out for more threatening space rocks.
“It was a pretty nasty event. Luckily, no one was killed but it just shows the sort of force that these things have,” said Alan Harris, senior scientist of the DLR Institute of Planetary Research in Berlin, in this new European Space Agency video.
An asteroid that is only about 100 meters (328 feet) in diameter, for example, “could actually completely destroy an urban area in the worst case. So those are the things we’re really looking out for and trying to find ways to tackle.”
Check out the video for some examples of how the Europeans are talking about dealing with this problem, including a fun comparison to cosmic billiards and a more serious discussion on how to shove these rocks aside if they were on a collision course with our planet.
