There is a group here at Goddard is called the HEASARC – High Energy Astrophysics Science Archive Research Center. This is where we keep data from old and new satellites. Even though every new satellite is an improvement over the last in one way or another, it is important to keep old data, with the expertise to go with it.
Think of Halley’s Comet – when Edmund Halley calculated the orbit of this comet from observations in 1682, he was able show that it was the same as the comets of 1531 and 1607 because there were sufficiently detailed records from those appearances.
Halley’s Comet. Credit: NASA
We now know of even earlier appearances of Halley’s Comet, dating back at least to the Chinese record of of a comet in 240 BC. Chinese court astrologers had a habit of making careful records of not only comets but novae and supernovae, which they collectively called “guest stars.” These records are invaluable to today’s astrophysicists who also use modern telescopes and satellites. For example, historical records can give you the precise age of a supernova since the explosion.
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.
The Universe is expanding faster and faster and faster! But, how do we know that? Our current knowledge of the Universe is built upon a foundation of research done by previous generations of scientists. Sometimes it seems that science moves slowly, but when you look back, it becomes clear just how far we have come in a short of time. (When you’re an astronomer, anything less than a few million years is very short!)
NASA’s Cosmic Times project takes a look at how our understanding of the Universe has changed from 1919, when astronomers believed the Universe was the size of our galaxy and infinitely old, to today, when astronomical evidence shows that the Universe is about 94 billion light years in size and about 14 billion years old. Cosmic Times traces these changes through a series of front-page newspapers from six different times over the past century.
Go find out how astronomers have come to their current understanding of the size, age, and nature of the Universe! What will we find out in the next 10 years?
I had the fortune to be invited last minute to the Tweet-up with Astronaut Ron Garan at NASA Headquarters yesterday, in the place of a co-worker who couldn’t go. And then last minute, I got drafted to actually help out! Sara and I have been to several tweet-ups, but this was the first time I worked one. It was a really cool experience. I got to help check people in and then run around with the microphone for the Q&A which was a challenge since I wanted to stay out of the camera’s way, not block people, but be quick getting to those with questions. And then I felt bad for those who weren’t able to get their questions in. I tried!
I had a great time and I also was often able to get a great view of the speaker, Astronaut Ron Garan. “Astro_Ron”, as he is known on Twitter, was an F-16 pilot (how cool is that?!) who became an astronaut in 2000. He flew on STS-124 to the ISS and on his second mission, spent six months there as a member of Expedition 27. He’s ridden on both the Space Shuttle and the Soyuz. And he had a lot of great stories to tell. He really saw some amazing things like aurorae, sunrises, incoming orbiters, hurricanes, and meteor showers. (You can page through more of his amazing images from space on his Twitpic.)
During nearly an hour of Q&A, Astro Ron also showed us this gag video called “Space Station Blues – The Sequel” that they shot right before he left the Space Station. (He had been told he’d have to stay for two more months, though it only ended up being an extra week.)
This beautiful, infrared image shows a new view of the Eagle nebula captured by the European Herschel Space Observatory. In 1995, Hubble famously captured a visble-light image of the “Pillars of Creation,” a region of star-formation. That image is below – in the above image, that region is shown within the circle.
Credit: NASA, Jeff Hester, and Paul Scowen (Arizona State University)
Infrared light is needed to see into the opaque clouds of dust and gas within which stars form. You can read more about what astronomers are learning from this new view of the nebula in the NASA feature.
Credit: NASA, ESA, C.R. O’Dell (Vanderbilt University), and M. Meixner, P. McCullough
The Helix Nebula is an iconic astronomical object – it’s been imaged again and again, by a variety of satellites. It’s one of those objects that gets turned into desktop wallpapers, posters, and postcards. It was even featured on a postage stamp issued in Great Britain in 2007. It’s one of those inspiring, mysterious images of space that people like to look at. And guess what – scientists like to look at it too!
The image above combines observations of the Helix from the the Advanced Camera for Surveys aboard the Hubble Space Telescope and the ground-based Cerro Tololo Inter-American Observatory in Chile (you can download it from HubbleSite). There are many similar images of the Helix in visible light, and others across a variety of wavelengths. Many satellites and ground-based observatories have turned their eyes towards the Helix Nebula. Read more »
We just recently blogged about some of the strange and wonderful planetary systems recently discovered. From Saturn-like rings, to miniature scale, to systems practically right out Star Wars, it seems that there are an indefinite number of possibilities out there.
Our questions to you are this:
Blueshift ponders: What kind of star system do you think it would be cool to discover, or alternatively, what would you like to find on an exoplanet? (Let’s discount “life” as an answer because we know it goes without saying!)
What are our opinions?
Maggie says: I’d love us to be able to really image some of the exoplanets we’ve discovered. We have such gorgeous images of the planets in our solar system – and there is such an interesting range of planets, from rocky to oceanic to gaseous giant – that I can’t wait until we have the capability to see what the planets in other star systems really look like.
I know we discounted “life”, but I think it would be interesting to see the range of planets that could exist in the habitable zones of other stars. (A habitable zone is the region around a star where a planet the temperatures are right for a planet to have liquid water on its surface.) Just this past December, Kepler-22b was discovered – the first confirmed extrasolar planet found by NASA’s Kepler Space Telescope to orbit within the habitable zone of a Sun-like star. That’s exciting stuff! Scientists don’t know yet if Kepler-22b has a predominantly rocky, gaseous or liquid composition. The artist’s interpretation below, which also compares Kepler-22b’s system to ours, shows it with clouds in its atmosphere. But I want to know what it really looks like!
Credit: NASA/Ames/JPL-Caltech
Sara says: I remember when I posed this question to a 5-year-old at an event… he was really hoping that we’d find a planet made of yellow Jell-O! It’s easy to think about how exciting it would be to find another Earth-like planet outside of our solar system – one with plenty of water, a protective atmosphere, and good prospects for life. But there are a lot of other things that would be interesting and useful to find in other solar systems! For one thing, how about more planets like each of our different planets, in terms of size and distance and general conditions? One of the great things about space is that you can look at lots of different objects in different phases of their lives. So imagine that you could see a Mars-like planet bring formed… and then other Mars-like planets that are more mature… and then another Mars-like planet as its system is being destroyed? Then you could learn a lot more about how Mars (and planets like it) are formed, live, and die. The formation of planetary systems is also really exciting – seeing more planet-forming disks and early systems would really enhance our understanding of how planets come to be. I’m enjoying all of the things that we’re learning as we find more and more planets. I remember when finding a planet was a really big deal, and now we’re constantly finding more candidates and progressively confirming that they’re really planets. We find a lot of normal ones, and then some really weird ones!
So now we want to know what you think! You can also respond with your opinion on our Facebook, or leave a comment here!
Meet the Nuclear Spectroscopic Telescope Array or NuSTAR – a new X-ray telescope that’s being launched in March of 2012. Below is the actual telescope in its pre-launch configuration:
Credit: NASA/JPL-Caltech/Orbital
And here is what it will look like post-launch!
Credit: NASA
NuSTAR has an interesting design that includes a deployable mast, which is used to extend the observatory to its full 10 meter focal length. Because this mast will flex slightly as the spacecraft orbits, NuSTAR employs a laser measurement system to monitor the degree of motion of the mirrors relative to the detectors.
NuSTAR will survey high-energy X-ray emission from black holes, help determine how chemical elements are cooked up in supernova explosions, and find new, previously unknown high energy sources. Gorgeous Chandra X-ray Observatory imagery has been done at relatively low X-ray energies – NuSTAR will extend the energy range of X-ray images by nearly a factor of 10, via breakthroughs in detector technology and X-ray optics.
This is a doozy of a round-up, thanks to the American Astronomical Society meeting mid-month! Maggie already blogged about some of the interesting exoplanet news that came out at the meeting. Here, we’ll cover some of the other big astrophysics releases at AAS! But first… a gorgeous image from the European Southern Observatory.
Credit: ESO
This image of the Omega Nebula (M17 or NGC 6618) was captured by the ESO’s ground-based Very Large Telescope (VLT). The nebula contains glowing hydrogen gas and filaments of dust, the very materials needed to create the the blue-white baby stars forming in this very active stellar nursery. You can read more about the nebula and this image in the ESO press release.
Apparently solar systems are also like a box of chocolates… As the saying goes, you never know what you’re going to get. At the recent American Astronomical Society (AAS) meeting in Austin, TX, I got to sit in on a press session on extrasolar planets, where three new systems were announced, each more bizarre than the next.
First was the announcement of the discovery of two new double-star planet systems found using Kepler data (Kepler-34 and Kepler-35). The first solar system similar to the fictional planet Tatooine from Star Wars (Kepler-16b) was actually discovered in 2011. It’s turning out that systems like the one containing Luke’s homeworld, which orbited twin suns, may be more common than previously thought.
Credit: Mark A. Garlick / space-art.co.uk
William Welsh of San Diego State University and Kepler participating scientist who led the study said, “This work further establishes that such ‘two sun’ planets are not rare exceptions, but may in fact be common, with many millions existing in our galaxy. This discovery broadens the hunting ground for systems that could support life.”
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