Monthly Archives: January 2011

AAS meeting stories, american astronomical society, astronomy media, astronomy news, galaxies, galaxy interactions, Milky Way Galaxy

More from the Astronomy Fire Hose

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Some Thoughts on a Galaxy of Possibilities

I am always amazed at the depth and breadth of discoveries in astronomy that get announced at these AAS meetings. I mean, we all KNOW it’s a big universe and there are always going to be amazing discoveries – but, what we don’t always know is just WHAT those finds will be.

Earlier today we heard from scientists using data from the Sloan Digital Sky Survey to create the largest multicolor image of the night sky. It’s essentially the Palomar Sky Survey of our time, but in digital format. You can browse through their work here, and eventually you’ll see much of their work in GalaxyZoo, World Wide Telescope, and GoogleSky.

As I sat there and listened to the scientists talk about their work, it struck me just how much astronomers learn each DAY and how LITTLE we see about it in the news media.  To be sure, there’s a LOT of news every day, and science has to struggle for attention among all the other events of our time.

An SDSS stellar map of the northern sky part of the sky as seen from Earth. It shows trails and streams of stars. These are from satellite galaxies of the Milky Way Galaxy that were torn apart as they strayed too far into our galaxy’s gravitational field of influence. The insets show new dwarf companions discovered by the SDSS (credit: V. Belokurov).

Did you know that astronomers are using the Sloan Survey using a technique called “spectroscopy” to look at the light from those stars and figure out their chemical compositions, the velocity (speed) they’re moving through space, and a host of other characteristics?  It’s true.  One of the coolest outcomes of such a study is that they can now tell which stars came from our own galaxy and which ones were or are parts of galaxies that are being sucked into the Milky Way galaxy.  Stars from galaxies being gobbled up have slight differences in their metallicity (the heavier elements they contain), as well as definite variations in their velocities and direction of travel.

These factors, in turn, give astronomers some important clues to how galaxies form – essentially, the Milky Way has gotten bigger by gobbling up stars from smaller galaxies that were once neighbors moving along the cosmic highway with it. Trace the characteristics of those stars spectroscopically and you learn more about the former neighbor satellites that are now mingling their stars with the Milky Way Galaxy.

Well… THAT was just one tiny part of what Sloan Digital Sky Survey scientists discussed this morning–just a small drip from the firehose of astronomy information flowing at this meeting.  There is literally a galaxy of science to be learned here.

AAS meeting stories, american astronomical society, astronomy, astronomy news, cassini mission, JWST, Kepler mission

More Astronomy than You Can Shake a Stick At

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A Sip from the Fire Hose of Astro Information

Every year in early January is “astronomy assimilation” time for me, a time when I can go and soak up all the latest in professional astronomy research. Yes, it’s the annual winter meeting of the American Astronomical Society.  Today’s the first full day of the conference and we hit the ground running.  I’ll be posting sporadic notes from the meeting over the next few days, including some highlighted astronomy discoveries that could make the news in between the coverage of the bad snowstorms and the very sad events in Tucson.

Part of Dr. Porco's talk focused on the dynamic causes of events called "propellers" in the Saturning rings. An unusually large propeller feature is detected just beyond the Encke Gap in this Cassini image of Saturn's outer A ring taken a couple days after the planet's August 2009 equinox.

Today’s meeting began with a short presentation about the future of space observational astronomy particularly as it will be seen through the James Webb Space Telescope. Following that was a wonderful talk sponsored by the Kavli Institute about Saturn’s rings and the observations made by the Cassini spacecraft that are enabling speaker Carolyn Porco and her team members to understand the dynamics of this evolving system.

The first press conference of the meeting featured the discovery of a new rocky world called Kepler-10b. It’s circling a star that lies about 600 light-years away and has been studied steadily by the Kepler planet-finding mission for more than eight months.  This is the first rocky world discovered by Kepler and it’s a fascinating one: it is about 1.4 times the size of Earth and orbits closer to its star than Mercury does to the Sun.

Kepler-10b is a scorched world, orbiting at a distance that’s more than 20 times closer to its star than Mercury is to our own Sun. The daytime temperature’s expected to be more than 2,500 degrees Fahrenheit, hotter than lava flows here on Earth. Intense radiation from the star has kept the planet from holding onto an atmosphere. Flecks of silicates and iron may be boiled off a molten surface and swept away by the stellar radiation, much like a comet’s tail when its orbit brings it close to the Sun.

There are several constants about these meetings — especially in these exciting days of spacecraft missions like Cassini, HST, and Kepler — and that is that we’ll always be hearing about new planets around other stars, we’ll keep learning new things about familiar objects like Saturn and its rings, and Hubble Space Telescope (and its sister orbiting observatories) will keep bringing us gorgeous images of the cosmos.
Each day of this meeting is chock full of papers and results to hear about. My own path through the meeting (at least today) is guided by radio astronomy results, and so I spent some time listening to presentations about early science from the Murchison Widefield Array in Australia and the search for the epoch of reionization at low frequencies.  It’s always amazing to me the new and inventive ways that astronomers can explore the universe and find out things we didn’t know before. The more of these meetings attend, the more I realize that even though we know a LOT – there’s so much more that we will be learning in the days and years and centuries ahead.