Fraser, Pamela and I have been whining remarking to each other that there is a huge amount of news coming from this meeting, and we’re having a heckuva time keeping up. Some is worth a long writeup, while others can probably be handled with a short post. Below are a few of the stories that are worth noting briefly.
And as a reminder: if you like what you’re seeing here, Digg the articles! Click the button at the top of the post, and it’ll help spread the word. Thanks!
1) The bigger the telescope the better, right? So what if your scope is the size of the Earth?
A technique called interferometry combines the light from telescopes that are widely separated, and with it you can make a virtual telescope that’s the same size as the distance between the physical telescopes. If those ’scopes are on opposite sides of the Earth, you get a telescope thousands of miles across. Using this technique, astronomers have made phenomenal measurements, including actually seeing the rotation of the galaxy M33 as well as its physical motion across the sky; something that had never been done before. They have been able to see the effects of the Sun’s motion around the Milky Way’s center, even though a full orbit takes 240 million years!
2) One long-standing mystery in astronomy is an apparent fountain of antimatter streaming out from the center of the Galaxy. What’s causing it? Most astronomers assumed it was coming from the giant supermassive black hole there, but now observations indicate it’s actually being accelerated by binary stars, where one of the two orbiting stars is a neutron star or black hole.
The cloud of antimatter is detected because it gives off gamma rays, which are a very high energy form of light. The gamma rays from the Galactic center are not centered on the center (hmmm, remember to edit that line), but extend a little bit more on the western side. This matches the distribution of the black hole or neutron star binaries. These binaries can generate antimatter when regular matter from the normal (sunlike) star swirls around the denser object.
I wrote about this in my book, so now I might have to do some editing. Nuts.
3) The most luminous objects in the Universe are, ironically and paradoxically, the faintest.
Huh?
Black holes can generate fantastic amounts of light as matter falling in to the hole first forms a disk around it. The disk is hot, and magnetic forces (along with friction and gravity) can make it extremely bright, as bright as billions of stars like the Sun. Supermassive black holes in the centers of galaxies are big, and have proportionately big disks which can outshine the rest of the galaxy in which it sits. We call these active galaxies, and there are different kinds (quasars, blazars, Seyferts) depending on the various characteristics of the galaxy.
It turns out, though, that in many cases our view of these black holes is blocked by tick gas and dust in the galaxy. The folks at the Sloan Digital Sky Survey have figured out a way to detect a fingerprint of these obscured galaxies, and found 887 hidden quasars that were previously unknown, by far the largest such sample ever made. What this means is that we have to be careful in the future about what objects we can and cannot see — astronomers may say "We expect to see XXX of these kind of galaxies and see none, which means our cosmology is wrong," we can take it with a judicious grain of salt.
January 11th, 2008 at 10:28 am
Have scientists (geologists and paleontologists most likely) ever detected evidence of any kind of ~240 millionish year cycles in the earth’s geology/climate/biodiversity/whatever that might be related to our being dragged, kicking and screaming, around the galactic centre of mass some 16 or so times by the Sun?
January 11th, 2008 at 11:17 am
Actually, yes. There may be some connection with this to the Sun bobbing up and down above and below the galactic midplane. Evidence is scant, but it might be because of intergalactic cosmic rays slamming into us when we’re above the midplane. I’d tell you more, but then you’d have no reason to read my longer explanation in the book when it comes out.
January 11th, 2008 at 11:21 am
Don’t forget to mention Reddit. It’s superior to Digg in many ways- and they also likey the Bad-Astronomy.
January 11th, 2008 at 12:31 pm
So with a radiotelescope on the Moon, would we be able to use that interferometrically with telescopes on Earth?
January 11th, 2008 at 12:34 pm
“… blocked by tick gas and dust …”
Did we turn Minnesotan all of a sudden, BA?
January 11th, 2008 at 12:55 pm
Ticks have gas all the time. They just blame it on the dog, however.
January 11th, 2008 at 2:20 pm
Antimatter jets from matter blackholes?
Are we seeing the divide?
Are there new, unfound laws, between matter and anyimatter, and the phisicics seperating the two?
Could energy vs anti-energy/dark energyy, driving the universe expansion.
Opposite polar forces?
Mirrors.
E=MC2=-_-E=MC2, -THE DIFFERENTAL OF MATTER VS CREATION of Antimatter and Dark energy.
Could our view of the trees that make up the forst, be not quite the whole picture?
JMHO (just my humble opinion) on my veiew of the trees, that make up the forest, from my viewpoint).
January 11th, 2008 at 5:55 pm
Ryan, don’t you mean B.Eh?
I’ve known that VLBI works with radio telescopes, but how far up the EM spectrum can it be useful? It’s akin to stereoscopic telescopes, but on much longer wavelengths, allowing for the long baselines, right?
January 11th, 2008 at 7:10 pm
I am, no…was…a lazy-eye freak who never, ever had a moment of binocular vision in his entire life until going under the knife a couple years ago at age 50, to have one of my eyeballs “rotated”, then months and months of therapy to teach my brain how to recognize and interpret the signals from two eyeballs working together for the first time in my entire life.
I really appreciate #1. Parallax is great stuff, I kid not. I have depth
perception for the first time…ever. I love it! I love seeing the world in 3-D!
Looking through our global eyeball on one side of our orbit around our sun and then comparing that image with what we see on the opposite side of our orbit is binocular vision times many, many, many orders of magnitude.
Mondo-cool!
January 11th, 2008 at 9:56 pm
UUUUMMMM! Anti-matter. Just what a hungry civilization needs.
Now, we really need to figure out how it’s done. IS it at all efficient? Could we possibly replicate the process, perhaps using the sun as a driving energy source?
I note, in SG-1, they never give any idea how the Ancients charged up their super compact power sources. I wonder if in some distant time, we might learn how to “expand” A Parallel space/time, from quantum size, to a space/time bubble capable of retaining energy sufficient to blow up a solar system,,,
Could use the infalling mass around a large black to power the sucker,,,
Ah, SCiFi, what a great genre,,,
GAry 7
January 16th, 2008 at 10:32 am
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