Protostars in Messier 78, as seen by multiple observatories
Credit: NASA/ESA/ESO/JPL-Caltech/Max-Planck
The side-by-side images above depict protostars found in Messier 78, a reflection nebula found within the constellation Orion (but not the Orion Nebula, which is Messier 42). These are some of the youngest stars that astronomers have ever seen – some of them are still embedded deeply in a gaseous envelope, which would suggest that they’re under 25,000 years old. That may seem like a long time compared to our human lives… but for stars that can live for millions or billions of years, it’s still stellar infancy. These images accompanied this press release from the Herschel space observatory, and represent observations from Herschel as well as ground-based telescopes. Though they can be difficult to detect, researchers are hoping to document more young stars in various stages of life – from before birth through infancy – to learn more about the early development of stars.
NASA often looks at “young” astronomical objects, to learn more about the formation and evolution of the Universe. Here’s a selection of some beautiful and interesting cosmic baby pictures… Read more »
Capturing the beauty of this galaxy took a team of people – and to understand the galaxy takes a team of missions.
This gorgeous image of galaxy M106 was created by renowned astro-photographer Robert Gendler, who retrieved archival Hubble images to assemble a mosaic of the center of the galaxy. He then used his own and fellow astro-photographer Jay GaBany’s observations to fill in areas where there was little or no Hubble data.
Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), and R. Gendler (for the Hubble Heritage Team) Acknowledgment: J. GaBany
The NASA feature written about this image tells us that Hubble data from the Advanced Camera for Surveys, Wide Field Camera 3, and Wide Field Planetary Camera 2 detectors were used for the center of the galaxy. The outer spiral arms are also Hubble data, but colorized with ground-based data taken by Gendler’s and GaBany’s 12.5-inch and 20-inch telescopes, which was captured at dark, remote sites in New Mexico.
Also visible are the optical component of the so-called “anomalous arms” of M106, which in this image are a red color, from glowing hydrogen emission. They’re called “anomalous” because they don’t line up very well with the galaxy’s more prominent spiral arms.
Each December, there’s a bit of a lull in astronomy news. Not only do the holidays slow things down, but astronomers are also getting ready for the winter meeting of the American Astronomical Society (AAS) in January. These AAS meetings (there’s also a summer meeting in May or June) are a particularly high-profile place to announce a groundbreaking discovery or other exciting piece of research – scientists are surrounded by their peers, with press conferences held daily throughout the week-long meeting. We’ve covered a few of these meetings in the past – you can learn more about AAS press conferences, follow Maggie’s adventures at the 2011 AAS meeting in Seattle, or even listen to our podcast from a meeting in 2010.
This year’s AAS winter meeting was held in Long Beach, CA, where astronomers got a bit of sunshine and sand as well as time to meet with their colleagues, present their research, and hear about the latest and greatest astronomy news. We wanted to share some of the highlights from the astrophysics press releases – and there are some particularly exciting ones in this meeting’s batch!
Credit: NASA, ESA, and A. Feild (STScI)
From a “zombie” to a “rogue” – the astronomy community still can’t get enough of the strange planet Fomalhaut b! First, there was controversy over whether it was a planet or a dust cloud, and now they’re looking at the planet’s unusual orbit within the debris disk of its host star, Fomalhaut. The planet’s highly elliptical, 2,000-year orbit leads astronomers to suspect that there may be other planet-like bodies hiding within the debris around Fomalhaut. One or more of these other bodies may have gravitationally disturbed Fomalhaut b, ejecting it from a position closer to the star and sending it on a wild and potentially destructive orbit through the debris disk. I’m sure this isn’t the last we’ve heard about Fomalhaut b, as astronomers are hoping to continue the hunt for other planets in its system, and to better understand its own characteristics. Read more »
I was inspired to pick up where Alexe left off with her “est” blogs, and write about “Farthest,” because of some recent, cool, astronomical news.
There was recently excitement over a Hubble Space Telescope discovery of seven primitive galaxies located over 13 billion light years away from us. The results are from survey of the same patch of sky known as the Ultra Deep Field (UDF). This survey, called UDF12, used Hubble’s Wide Field Camera 3 to peer deeper into space in near-infrared light than any previous Hubble observation.
Why infrared? Because the Universe is expanding; therefore the farther back we look, the faster objects are moving away from us, which shifts their light towards the red. (The opposite of the our namesake effect, blueshift!) Redshift means that light that is emitted as ultraviolet or visible light is shifted more and more to redder wavelengths. Spectral features from galaxies that we normally see in UV or visible are likewise shifted into infrared, particularly for the most distant things. Without infrared light we might not see those features, and thus couldn’t determine the distance to these far away objects.
The extreme distance of these newly discovered galaxies means their light has been traveling to us for more than 13 billion years, from a time when the Universe was less than 4% of its current age. (Current observations suggest that the Universe is about 13.7 billion years old.)
Credit: NASA, ESA, R. Ellis (Caltech), and the UDF 2012 Team
With every year that passes, our newest technology enables us to see further and further back. The microwave afterglow of the Big Bang that was seen by the COBE and WMAP satellites is from about 378,000 years after the Big Bang. That’s a long time ago to be sure, but it was also before the first objects in the universe formed.
The questions are, how far back can we see at visible and infrared wavelengths? And what can we see?
The timing couldn’t have been more perfect – just days before Halloween, NASA released a story about a planet that had returned from the dead. The exoplanet, Fomalhaut b, was discovered in 2008 using data from the Hubble Space Telescope. More recently, other researchers suspected it might be a dust cloud instead, so its planetary status was revoked. However, even newer research has caused astrophysicists to reverse the decision once again – Fomalhaut b is a planet once more!
Credit: NASA
How did this happen? What makes Fomalhaut b so tricky to interpret? We wanted to go right to the source, so we got in touch with the head of the team that helped bring this planet back from the dead. Dr. Thayne Currie is a recent NASA Postdoctoral Fellow at Goddard Space Flight Center and is currently in the Department of Astronomy and Astrophysics at the University of Toronto.
Blueshift:Can you tell us a little bit about yourself? What is the focus of your research at Goddard?
Thayne Currie: My focus at Goddard was primarly to look for new planets via direct imaging and better characterize the properties (atmospheres, orbits) of known directly imaged planets. I also did some research studying planet formation and planet-forming disks via infrared photometry and spectroscopy. Read more »
Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
Hubble captured this wonderful image that looks very much like an outer space firework explosion. Herbig-Haro 110 is a geyser of hot gas being blown away from a newborn star that ricochets off the dense core of a cloud of molecular hydrogen. Herbig-Haro 110 is one of a collection of the group of Herbig-Haro objects that come in a variety of shapes, but still have the same basic configuration. Twin jets of heated gas are ejected out from a newly formed star and stream through the space between stars. Astronomers suspect that these jets are fueled by gas and dust falling onto a young star. The disk acts as the fuel tank, the star acts as the gravitational engine, and the jets are the exhaust. When these jets slam into the gas between stars, it heats up the gas, causing it to glow. Gas within the shock front slows dramatically, but more gas just keeps building up behind it, causing more glowing (These “bow shocks” are so names because they resemble the waves that form at the bow of a boat). By studying these structures carefully, astronomers can “rewind” them, in a way, in order to study the star’s history. Read more »
Voyager is soon to be the first man-made object to leave the solar system. Data from NASA’s Voyager 1 spacecraft indicate that this deep space explorer has entered a region in space where the number of charged particles from beyond our solar system has significantly increased. This could mean that Voyager 1 may be at the edge of our solar system and about to leave it. The spacecraft Voyagers 1 and 2 were launched in 1977, originally designated to study Jupiter and Saturn, but have since continued their journey on to study the outer solar system. The image above depicts where the Voyager spacecraft are in relation to our solar system and the surrounding area.
The Voyager team is looking at a few specific things that they expect will tell them when the spacecraft has punched through the ‘heliosheath’ – a kind of bubble around our solar system where stellar winds slow down dramatically. First, a great increase in the number of galactic cosmic rays (energetic charged particles from outside our solar system). The numbers appear to be on the rise, which is a good sign that Voyager 1 is getting close to the heliosheath. The team is also looking at the intensity of energetic particles from inside the heliosphere. These have been steadily decreasing but have yet to drop off abruptly, as would be expected when the craft leaves the heliosphere. Lastly, there is the measurement of the direction of the magnetic field lines surrounding the spacecraft. Currently, while the craft remains in the heliosphere, the field lines run east-west. However, when it passes into interstellar space, it is thought that the field lines will switch to running more north-south. There is still much analysis of the data to be done, but we can still expect that one day Voyager will be our first man-made ambassador to interstellar space. Read more »
We posted once about NuSTAR, a new X-ray telescope. It was due to be launched in March, but that launch date is now scheduled for June. Below is a great new image of NuSTAR in the nose cone of the Pegasus rocket it will be launched on.
Credit: NASA
Using NASA’s Galaxy Evolution Explorer, a space-based observatory, and the Pan-STARRS1 telescope on the summit of Haleakala in Hawaii, astronomers have gathered the most direct evidence yet of a supermassive black hole shredding a star that wandered too close.
Credit: NASA, S. Gezari (The Johns Hopkins University), and J. Guillochon (University of California, Santa Cruz)
“When the star is ripped apart by the gravitational forces of the black hole, some part of the star’s remains falls into the black hole while the rest is ejected at high speeds,” said project lead Suvi Gezari of the Johns Hopkins University. “We are seeing the glow from the stellar gas falling into the black hole over time. We’re also witnessing the spectral signature of the ejected gas, which we find to be mostly helium. It is like we are gathering evidence from a crime scene. Because there is very little hydrogen and mostly helium in the gas, we detect from the carnage that the slaughtered star had to have been the helium-rich core of a stripped star.”
The above image and this video are computer simulations:
The video shows a star being shredded by the gravity of a massive black hole. As the video caption says, “Some of the stellar debris falls into the black hole and some of it is ejected into space at high speeds. The areas in white are regions of highest density, with progressively redder colors corresponding to lower-density regions. The blue dot pinpoints the black hole’s location. The elapsed time corresponds to the amount of time it takes for a Sun-like star to be ripped apart by a black hole a million times more massive than the Sun.”
Credit: NASA, ESA, D. Lennon and E. Sabbi (ESA/STScI), J. Anderson, S. E. de Mink, R. van der Marel, T. Sohn, and N. Walborn (STScI), N. Bastian (Excellence Cluster, Munich), L. Bedin (INAF, Padua), E. Bressert (ESO), P. Crowther (University of Sheffield), A. de Koter (University of Amsterdam), C. Evans (UKATC/STFC, Edinburgh), A. Herrero (IAC, Tenerife), N. Langer (AifA, Bonn), I. Platais (JHU), and H. Sana (University of Amsterdam)
Star-forming region 30 Doradus is colloquially known as the Tarantula Nebula (creepy!), but this new image released with data from Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys makes it look more like a rich underwater scene. Located within our galaxy’s close neighbor, the Large Magellanic Cloud, it is one of the best stellar nurseries for astronomers to observe prolific star birth and learn more about how young stars form and grow. This image combines dozens of observations from Hubble, showing off star clusters at varying ages. The false color in this image represents the hot gas within the regions – red signifies hydrogen gas and blue represents oxygen. What a tangled web these stars weave!
Credit: NASA, ESA, CFHT, CXO, M.J. Jee (University of California, Davis), and A. Mahdavi (San Francisco State University)
Astronomers have observed what appears to be a clump of dark matter left behind from a wreck between massive clusters of galaxies. The result could challenge current theories about dark matter.
The above image shows the distribution of dark matter, galaxies, and hot gas in the core Abell 520, a merging galaxy cluster formed by violent collision. It is a composite of data from several sources. The natural-color image of the galaxies is from the Hubble Space Telescope and the Canada-France-Hawaii Telescope in Hawaii. Superimposed on it are false-color maps showing the concentration of starlight, hot gas, and dark matter in the cluster.
Starlight from galaxies, derived from observations by the Canada-France-Hawaii Telescope, is colored orange. The green-tinted regions show hot gas, as detected by the Chandra X-ray Observatory. The gas is evidence that a collision took place. The blue-colored areas pinpoint the location of most of the mass in the cluster, which is dominated by dark matter. Dark matter is an invisible substance that makes up most of the universe’s mass. The dark-matter map was derived from the Hubble Wide Field Planetary Camera 2 observations, by detecting how light from distant objects is distorted by the cluster galaxies, an effect called gravitational lensing.
The blend of blue and green in the center of the image reveals that a clump of dark matter resides near most of the hot gas, where very few galaxies are found. This could present a challenge to basic theories of dark matter, which predict that galaxies should be anchored to dark matter, even during the shock of a collision.
Blogs | Sara Mitchell | 
March 22, 2013 4:15 pm | 
Comments (0) 
Subscribe
