Archive for May, 2007
May 31st, 2007
Comments(3) The Sun and its Danger Zone: The ChromosphereOne of the deeply confusing aspects of our Sun (and other stars) is their temperature structure. Starting in the core, the Sun is millions of degrees kelvin and supports nuclear burning. As you leave the nuclear burning core and climb first into the radiative zone and then the convective zone, the temperature systematically drops until it reaches a temperature of several 1000 degrees at a star’s surface. This makes sense. In the core, the gas is being compressed under the pressure of all the upper layers of the star gravitationally pushing down. The pressure allows nuclear reactions to release energy in a form that can heat things up: specifically light. That light then interacts with stellar material, being absorbed and reabsorbed over and over as it loses energy and goes on a random walk through the radiative region (think light bulb heating the air around it), and then (think of the lava lamp material above a light bulb) it also gives off energy as it heats cells of material at the base of the convective zone that rise and convectively give off heat as the cells rise (and then, when cool, sink back down). So far so good. The problem is, as you then move away from the surface of the Sun, you enter regions where the temperatures again go up - A lot - like back to millions of degrees hot levels of a lot! And no one fully knows why. This is a very counter intuitive situation. Imagine that the surface of a lava lamp was 23C and the air half an inch away was 200C! In a press conference Wednesday, astronomers announced that they think they may have found a starting point for understanding what is going on in this bizarre situation. Read more...
May 31st, 2007
Comments(0) Party at the AAS
May 30th, 2007
Comments(5) Giving AAS a Face
May 29th, 2007
Comments(0) “The Universe” on TV
May 29th, 2007
Comments(1) All the news you’ll see again: Solar Atmospheric Heating, Tidal Tails, and Crab Nebula Explosion DateHere’s highlights of the news I’ll be talking about later:
New results, new press conferences and press releases, and, well, the same old same old. Science moves forward in incremental steps, and sometimes things circle and circle as they slowly move forward. Read more...
May 29th, 2007
Comments(1) Black Holes and their SpinThere are two basic characteristics that describe black holes: Mass and Spin. Mass determines the size of the event horizon, the gravitational mass, and many of the ways the black hole can gravitationally shred people, planets and just about anything else. Spin is related to the magnetic field (which can also shred people because of the magnetic properties of water), and it exerts many relativistic effects on its surrounding, such as frame dragging. Black hole spin also allows the black hole’s associated accretion disk to extend closer in toward the event horizon, creating a (with future higher resolution telescopes) a directly imaginable effect. In a trio of spin related press releases, scientists described how to measure spin, the consequences spin has on how black holes merge, and results on a test to check if our understanding is wrong. Read more...
May 29th, 2007
Comments(1) All that’s sorta new in ExoplanetsYesterday’s big afternoon press conference was all about exoplanets. The scientists took us on a tour de force of planet related press releases that went from little M stars and their tiny habitable zone, to a new press release on 28 planets, to planets found around sub-giant stars that were A-stars when they were on the main sequence. The catch was, while none of these stories had previously had related press releases, many of them (but not all) had related published papers or published pre-prints in the arXiv pre-print sever. Read more...
May 28th, 2007
Comments(3) Galactic Morning: Andromeda XII, M81, and a Pushy Void
May 28th, 2007
Comments(4) An Apple World
This I walked into the press conference room and their was a giant, fresh from the press, printed Hubble Heritage image off to the side. Okay that’s cool. What really caught my eye was the three scientists and their three Apple laptops.
May 27th, 2007
Comments(0) The search for Chotchkies and Bling-BlingOne of the odd side activities at AAS meetings is the search for neat give aways from the different space missions, companies, and publishers. These items generally take the form of lanyards, pens, and posters. I picked up something kind of new and neat and just in time for pool parties last night : A WMAP beach ball depicting the cosmic microwave background. I’ll now be able to toss the fingerprint of the big bang around my classroom or back yard. There was also a happy cheerful button that proclaimed “I’m a Scientist” with a telescope and satellite. And this was just at a pre-meeting dinner. Currently, it’s looking like I should have brought a bigger bag. Read more... |





Tonight there will be a celebration of community building involving cocktails. To get details, just
There is an excellant
This mornings first press conference spanned the scales of the Universe. From a high speed dwarf galaxy only 1/20,000 times the size of our galaxy, to a new picture of
Short message while I write longer content on this mornings first, galaxy rich, press conference.