A graphic designer in Rhode Island, Jason writes about space exploration on his blog Lights In The Dark, Discovery News, and, of course, here on Universe Today. Ad astra!
Although somewhat blobby and deformed, this is in fact a spiral galaxy, located in the southern constellation Hydra. Imaged by Hubble as part of a survey of galactic bulges, NGC 4980 exhibits what’s called a “pseudobulge” — an inline central concentration of stars whose similar spiral motion extends right down into its core.
As opposed to classical bulges, in which stars orbit their galaxy’s core in all directions, pseudobulges are made up of stars that continue along the spiral motion of the galactic arms all the way into the center. Pseudobulges are typically seen to contain stars that are the same age as most of the others in the galaxy.
In contrast, classical bulges usually contain stars older than those found in the disk, leading astrophysicists to believe that galaxies with classical bulges had undergone one or more collisions with other galaxies during their evolution.
Our own Milky Way is thought to have a pseudobulge, while some spiral galaxies have no discernible bulge at all.
This image is composed of exposures taken in visible and infrared light by Hubble’s Advanced Camera for Surveys. The image is approximately 3.3 by 1.5 arcminutes in size. NGC 4980 is located about 80 million light-years from Earth.
View of Mars from Viking 2 lander, September 1976. (NASA/JPL-Caltech)
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The Curiosity rover is currently on its way to Mars, scheduled to make a dramatic landing within Gale Crater in mid-August and begin its hunt for the geologic signatures of a watery, life-friendly past. Solid evidence that large volumes of water existed on Mars at some point would be a major step forward in the search for life on the Red Planet.
But… has it already been found? Some scientists say yes.
Researchers from universities in Los Angeles, California, Tempe, Arizona and Siena, Italy have published a paper in the International Journal of Aeronautical and Space Sciences (IJASS) citing the results of their work with data obtained by NASA’s Viking mission.
The twin Viking 1 and 2 landers launched in August and September of 1975 and successfully landed on Mars in July and September of the following year. Their principal mission was to search for life, which they did by digging into the ruddy Martian soil looking for signs of respiration — a signal of biological activity.
A six-inch-deep trench in the Martian soil dug by Viking 1 in February 1977. The goal was to reach a foot below the surface for sampling.
The results, although promising, were inconclusive.
Now, 35 years later, one team of researchers claims that the Viking landers did indeed detect life, and the data’s been there all along.
“Active soils exhibited rapid, substantial gas release,” the team’s report states. “The gas was probably CO2 and, possibly, other radiocarbon-containing gases.”
By applying mathematical complexities to the Viking data for deeper analysis, the researchers found that the Martian samples behaved differently than a non-biological control group.
“Control responses that exhibit relatively low initial order rapidly devolve into near-random noise, while the active experiments exhibit higher initial order which decays only slowly,” the paper states. “This suggests a robust biological response.”
While some critics of the findings claim that such a process of identifying life has not yet been perfected — not even here on Earth — the results are certainly intriguing… enough to bolster support for further investigation into Viking data and perhaps re-evaluate the historic mission’s “inconclusive” findings.
An impact between a Mars-sized protoplanet and early Earth is the most widely-accepted origin of the Moon. Did smaller impacts seed the formation of continents? (NASA/JPL-Caltech)
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Recent research on lunar samples has shown that the Moon may be made of more Earth than green cheese — if by “green cheese” you mean the protoplanet impactor that was instrumental in its creation.
It’s an accepted hypothesis that Earth’s moon was created during an ancient, violet collision between our infant planet and a Mars-sized world called Theia, an event that destroyed Theia and sent part of Earth’s crust and upper mantle into orbit as a brief-lived ring of molten material. This material eventually coalesced to form the Moon, and over the next 4.5 billion years it cooled, became tidally locked with Earth, accumulated countless craters and gradually drifted out to the respectable distance at which we see it today.
Theia’s remains were once assumed to have been a major contributor to the material that eventually formed the Moon. Lunar samples, however, showed that the ratio of oxygen isotopes on the Moon compared to Earth were too similar to account for such a formation. Now, further research by a team led by scientists from The University of Chicago shows that titanium isotopes — an element much more refractive than oxygen — are surprisingly similar between the Moon and Earth, further indicating a common origin.
“After correcting for secondary effects associated with cosmic-ray exposure at the lunar surface using samarium and gadolinium isotope systematics, we find that the 50Ti/47Ti ratio of the Moon is identical to that of the Earth within about four parts per million, which is only 1/150 of the isotopic range documented in meteorites,” wrote University of Chicago geophysicist Junjun Zhang, lead author of the paper published in the journal Nature Geoscience on March 25.
If the Moon is more Earth than Theia, then what happened to the original impacting body? Perhaps it was made of heavier stuff that sunk deeper into the Moon, or was assimilated into Earth’s mantle, or got lost to space… only more research will tell.
But for now, you can be fairly sure that when you’re looking up at the Moon you’re seeing a piece of Earth, the cratered remnants of a collision that took place billions of years ago.
Is this amazing footage of a fireball over San Antonio on April 2?
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On April 2, 2012, at around 11:50 am CDT, dozens of people in and around San Antonio, Texas witnessed a bright object streaking across the daytime sky. Most likely a fireball — a particularly large, bright meteor — the object was visible across a very large area. It even made the local WOAI4 NBC news, which sent reporters out to interview eye-witnesses, contacted a NASA meteor expert, and ultimately featured a video of the amazingly bright fireball as it blazed through the sky. Very dramatic.
Except… the video isn’t of a fireball at all.
For the record, there was a meteor spotted over San Antonio on April 2… it was reported on the Lunar Meteorite Hunters site as well as in local papers. The eyewitnesses in the WOAI video were indeed describing what they saw, as well as they could. But the “footage” that was revealed later in the video wasn’t of a meteor; rather, it was something much more terrestrial.
It appears to be an airplane contrail, illuminated by sunlight.
Unfortunately this didn’t stop the segment from airing on TV, or from being picked up by syndicated news over a week later to appear on several online news sites.
At first glance the video does appear to show something fiery descending from the sky, leaving a long, bright trail in its wake. But that’s exactly how contrails can look when lit up by low-angle sunlight. It’s not necessarily a common sight to most people, but it’s common enough that those who have seen it would recognize that the video was, for lack of a better term, inaccurate. And inaccuracies can all-too-easily spread into a fire of misinformation — especially when concerning “things from the sky”.
Sunlit contrail in Germany masquerading as a fiery meteor (Mick West)
Experienced pilot Mick West describes the phenomenon on his blog ContrailScience.com:
“This is a remarkably common news story: It’s just after sunset, someone looks towards the west and they see the short contrail of a jet plane illuminated by the sun. It looks red, like fire. They zoom in with their video camera. They don’t know what it is, thinking it’s a fireball, a meteor, or some kind of UFO, so they alert the local media. The local media published it, and occasionally the story grows.”
Even though the April 2 fireball wasn’t seen at sunset or sunrise, the video footage wasn’t from the actual event. This means not only is it not of a meteor it’s not even from the right time of day. One has to wonder where in fact it was actually shot from, and by whom.
I don’t know if the contrail footage was sent in to the news channel intentionally, or if it was just an error due to lack of research. Regardless, it’s a good example of why facts and sources need to be checked!
Luckily there are those who know a contrail from a meteor, and thanks to the miracle of modern social networking such information discrepancies can be rectified in short order.
Photo by Expedition 30 crew during a night pass over Moscow on March 28, 2012.
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Tracing a bright star upon the Earth, the lights of Russia’s capital city blaze beyond the solar panels of the International Space Station in this photo, captured by the Expedition 30 crew on the night of March 28, 2012.
As an electric-blue dawn flares around Earth’s northeastern limb, the green and purple fire of the Aurora Borealis shimmers and stretches away to the northwest above a pale yellow line of airglow.
Traveling at 17,500 miles an hour (28,163 km/hr), the ISS was approximately 240 miles (386 km) above the Russian city of Volgograd (formerly Stalingrad) when this photo was taken.
Size comparison of a Space Shuttle and a Soyuz capsule.
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Here’s an interesting illustration showing the size comparison of a Space Shuttle to a Soyuz vehicle, shared on Twitter by NASA astronaut Rick Mastracchio (@AstroRM). Amazing to think that three flight-suited astronauts are able to fit inside a Soyuz and have life support for up to a month! (Although I’m sure most hope they won’t have to stay that long.)
Compare the 7-person capacity, 65.8 cubic meter crew cabin of an orbiter to the 3-person, 10 cubic meter space inside a Soyuz and one can imagine how cozy it must get during trips to and from the Station.
Rick is currently in training for a Soyuz flight to the ISS in November of next year as a member of the Expedition 38 crew, at which time he’ll get plenty of first-hand experience with the precise interior measurements of a Soyuz.
Thanks to Rick for sharing this! You can find out more about the Soyuz vehicles here, and check out the full source publication MIR Hardware Heritage (1995) by David S. F. Portree for Johnson Space Center.
The bright object in the center of this video sequence is the planet Mercury, seen by NASA’s STEREO-B spacecraft as it was pummeled by wave after wave of solar material ejected from the Sun during the week of March 25 – April 2, 2012.
The video above was released by NASA’s Goddard Space Flight Center earlier today. The Sun is located just off-frame to the left, while Earth would be millions of miles to the right.
Proof that it’s not easy being first rock from the Sun!
A cluster of coronal cells seen by SDO on June 17, 2011. (NASA/SDO AIA instrument)
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There’s something new under the Sun… well, just above the Sun, actually. Scientists at the Naval Research Laboratory have spotted structures in the Sun’s super-hot corona that may shed some light on the way its magnetic fields evolve — especially near the edges of vast, wind-spewing coronal holes.
Coronal holes are regions where the Sun’s magnetic field doesn’t loop back down but rather streams outward into space. Appearing dark in images captured in ultraviolet wavelengths, these holes in the corona allow solar material to flow directly out into the solar system, in many cases doubling the normal rate of the solar wind.
Recently witnessed by NRL researchers using NASA’s SDO and STEREO solar-observing spacecraft, features called coronal cells exist at the boundaries of coronal holes and may be closely associated with their formation and behavior.
The coronal cells are plumes of magnetic activity that stream upward from the Sun, occurring in clusters. Likened to “candles on a birthday cake”, the incredibly hot (1 million K) plumes extend outwards, punching though the lower corona.
Seen near the center of the Sun’s disk, the cells appear structurally similar to granules — short-lived areas of rising and falling solar material on the Sun’s photosphere — but seen from an angle via STEREO, the cells were witnessed to be much larger, elongated and extending higher into the Sun’s atmosphere. For comparison, granules are typically about 1,000 km in diameter while the coronal cells have been measured at 30,000 km across.
“We think the coronal cells look like flames shooting up, like candles on a birthday cake,” said Neil Sheeley, a solar scientist at the Naval Research Laboratory in Washington, D.C. “When you see them from the side, they look like flames. When you look at them straight down they look like cells. And we had a great way of checking this out, because we could look at them from the top and from the side at the same time using observations from SDO, STEREO-A, and STEREO-B.”
Watch a video below of cells made from images acquired by STEREO-B… note how their elongated structure becomes evident as the cells rotate closer to the Sun’s limb.
NRL researchers also noted that the coronal cells appeared when adjacent coronal holes closed and disappeared when the holes opened, suggesting that the holes and cells share the same magnetic structure. In addition, the coronal cells were seen to disappear when a solar filament would erupt nearby, being “extinguished” as the cooler strand of solar material moved across them. Once the filament passed, the cells reformed — again, indicating a direct magnetic association.
The coronal cells were also identified in earlier images from ESA and NASA’s SOHO and Japan’s Hinode spacecraft.
It’s hoped that further study of these candle-like structures will lead to more knowledge of our star’s complex magnetic field and the effects it has on space weather and geomagnetic activity experienced here on Earth.
Read the press release from the Naval Research Laboratory here, and on NASA’s STEREO site here.
The MOSFIRE instrument's "first light" image of The Antennae galaxies, acquired on April 4 2012.
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Last week, on April 4, 2012, the W.M. Keck Observatory’s brand-new MOSFIRE instrument opened its infrared-sensing eyes to the Universe for the first time, capturing the image above of a pair of interacting galaxies known as The Antennae. Once fully commissioned and scientific observations begin, MOSFIRE will greatly enhance the imaging abilities of “the world’s most productive ground-based observatory.”
Installed into the Keck I observatory, MOSFIRE — which stands for Multi-Object Spectrometer For Infra-Red Exploration — is able to gather light in infrared wavelengths. This realm of electromagnetic radiation lies just beyond red on the visible spectrum (the “rainbow” of light that our eyes are sensitive to) and is created by anything that emits heat. By “seeing” in infrared, MOSFIRE can peer through clouds of otherwise opaque dust and gas to observe what lies beyond — such as the enormous black hole that resides at the center of our galaxy.
MOSFIRE can also resolve some of the most distant objects in the Universe, in effect looking back in time toward the period “only” a half-billion years after the Big Bang. Because light from that far back has been so strongly shifted into the infrared due to the accelerated expansion of the Universe (a process called redshift) only instruments like MOSFIRE can detect it.
The instrument itself must be kept at a chilly -243ºF (-153ºC) in order to not contaminate observations with its own heat.
Astronomers also plan to use MOSFIRE to search for brown dwarfs — relatively cool objects that never really gained enough mass to ignite fusion in their cores. Difficult to image even in infrared, it’s suspected that our own galaxy is teeming with them.
The impressive new instrument has the ability to survey up to 46 objects at once and then do a quick-change to new targets in just minutes, as opposed to the one to two days it can typically take other telescopes!
Unprocessed image of M82 taken with MOSFIRE on April 5, 2012. (W. M. Keck Observatory)
Images taken on the nights of April 4 and 5 are just the beginning of what promises to be a new heat-seeking era for the Mauna Kea-based observatory!
“The MOSFIRE project team members at Keck Observatory, Caltech, UCLA, and UC Santa Cruz are to be congratulated, as are the observatory operations staff who worked hard to get MOSFIRE integrated into the Keck I telescope and infrastructure,” says Bob Goodrich, Keck Observatory Observing Support Manager. “A lot of people have put in long hours getting ready for this momentous First Light.”
The two Keck 10-meter domes atop Mauna Kea. (Rick Peterson/WMKO)
Read more on the Keck press release here.
The W. M. Keck Observatory operates two 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Big Island of Hawaii. The spectrometer was made possible through funding provided by the National Science Foundation and astronomy benefactors Gordon and Betty Moore.
Named after the 17th-century metaphysical poet, Mercury’s Donne crater was captured in this image by NASA’s MESSENGER spacecraft. The 53-mile (83-km) -wide crater features a large, rounded central peak and numerous lobate scarps lining its floor.
Lobate scarps are found all across Mercury. Visible above as arc-shaped ridges, they are most likely thrust faults resulting from surface compression and contraction.
Donne’s central peak has been well-eroded by impacts into a softly rolling mound. Central peaks are common features of larger craters, thought to be formed when the excavation of material during an impact springs the crater floor upwards — a process called “isostatic rebound”.
This image was acquired by MESSENGER’s Narrow-Angle Camera (NAC) on August 2, 2011.
On March 17 MESSENGER successfully wrapped up a year-long campaign to perform the first complete reconnaissance of the geochemistry, geophysics, geologic history, atmosphere, magnetosphere, and plasma environment of Mercury. The following day, March 18, marked the official start of its extended phase designed to build upon those discoveries.
“Six plus years of cruise operations, capped by a year of nearly flawless orbital operations, with an additional year of scientific return ahead in the harsh environment at 0.3 astronomical units (27,886,766 miles) from the Sun,” said MESSENGER Mission Systems Engineer Eric Finnegan at JHU/APL. All this “achieved with a 1,000 kg satellite, designed, built, and launched in less than four years for a total mission cost of less than $450 million.”
Well “Donne”, MESSENGER!
Read more about the MESSENGER mission’s extension here.
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.
