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New Galactic Neighbor
Dan Yocum writes "The Sloan Digital Sky Survey reveals a new Milky Way neighbor: a galaxy so big we couldn't see it before. A huge but very faint structure, containing hundreds of thousands of stars spread over an area nearly 5,000 times the size of a full moon, has been discovered and mapped by astronomers of the Sloan Digital Sky Survey."
Can't see the galaxy for the stars, eh?
Great minds think alike; fools seldom differ.
What makes this a galaxy rather than just some random swirl in the cosmos? (TFA doesn't really say)... does this galaxy have a black hole to call its own in the middle? What happens if a black hole eats another black hole?
If the g'vt kept the data on you that google does you'd better believe you'd be calling it "doing evil"
Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light.
And it's headed this way!!!!!!!
Are you...Are you some kind of genius?
No, ma'am, I'm just a regular Slashdot reader.
Could this be what's warping the Milky Way, previously thought to be Dark Matter?
Why is it that when you believe something it's an opinion, but when I believe something it's a manifesto?
It's a trap!!!!
It's a "dwarf galaxy" and yet so big we couldn't see it before?
Support the First Amendment. Read at -1
Quite frankly this is the kind of science that the Hubble cannot do. For one, the Hubble is designed for a finer spatial clarity, hence its field of view is so tiny that surveying the entire sky would literally takes decades (if not a century).
This work instead shows how invaluable ground observatories (esp the small ones) are. It's not a super-flashy job; it's a long, time-consuming, and slow-rewarding job. But once you've done it, you get your 15 minutes of fame (actually, in this case, you may make it into the history book).
"spread over an area nearly 5,000 times the size of a full moon,"
.5 degree
Interesting wording.
So that must mean 5000 full moons in the sky?
Moon = 1800 arc seconds
or 1800/60 = 30 arc minutes.
or 30/60 =
So what is that in degree of sky?
A fist at arms length is roughly 10 degrees.
I am not well versed in astronomy in general, but how could it be so faint we havent noticed it yet? Isint there a certain level of luminosity that is required to be a star? Could there possible be something between us and this galaxy?
I was a graduate student at the Astrophysical Sciences deptarment at Princeton when they were planning and starting to build the SDSS. A few interesting facts:
Some very clever optics (designed by James Gunn) went into the telescope. Normal telescopes do not produce the large field of view required. There were existing specialized telescopes which did (Schmidt cameras) but they have the imaging plane in the wrong place.
The main camera uses 30 2k x 2k CCDs, cooled by liquid nitrogen. At the time (early '90s) these cost on the order of $200k per chip.
The camera works in "drift scan" mode: the telescope moves such that the images of the stars drift along the columns of detectors in the CCDs. The packets of charge are shifted along the CCDs at the same rate - so instead of producing distinct individual frames, it continuously outputs data along an ever-lengthening strip along the sky. As I recall, the data rate is about 8Mbyte/s.
The camera spends rather more time on spectroscopy than imaging. (The imaging is primarily about selecting targets for the spectroscopy.) The spectrograph does 640 objects at a time. A computer-drilled plate is (manually) plugged with fibre optic cables in the right positions for that field of sky.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
I wonder where he got 3d glasses that make stuff look 3d in real life? I could use some of them to stop walking into walls so much!
Ah, a parliament or congress.
We've been here a while now. We did the Veni, Vidi, Vici thing, you just don't know it yet, but, yea, all your base are belong to us.
Well, now we know. Little did we know that we knew all along.
And the brethren went away edified.
Actually, things at that distance are far less 3D to your eyes than the molecules making up the things in the picture on a flat piece of paper on the table in front of you.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
This is like that part in the movie or the comic book, where the guy is tripping out or whatever, and he's staring into the dark void of space, and then slowly he realizes he's staring into a GIANT FUCKING EYE!
Computers are useless. They can only give you answers.
-- Pablo Picasso
"before they invade us,"
Optimistic, aren't you?
Even worse, if you consider that we are the aliens, and our species has simply invaded and conquered this planet an aen ago. We adapted, survived, and destroyed our own history. If you don't understand the destroyed part of that, go to a library and read some 6,000 year old books. Assuming you knew the language, you wouldn't find the books. They're lost, damaged, and/or intentionally destroyed over the years.
We are the aliens, and our brothern have forgotten about us. We will be stuck here, alone, for a long time.
Serious? Seriousness is well above my pay grade.
Yes, see Larry Niven's Protector.
Sounds an awful lot like witchcraft, if you ask me. I think we should burn you and the moon, just to be sure.
You better watch out, there may be dogs about . .
They know you're lying when you tell them "You can't see it because it's so big".
Book burning theories don't add much to our understanding of antiquity: Until the second or third century CE they only had parchment. Parchment was only good for a few hundred years, unless you kept it in a *very* dry cave in the desert somewhere. (And preferably made frequent backups.) The story of ancient history is that if your ideas (or you) went out of popularity, your books didn't get actively copied, and were therefore lost -- it's completely irrespective of whether anyone was actively destroying them or not. Unless you had the requisite desert caves, you needed a chisel to have any chance.
Now, for the period you're talking about -- from late stone age to early chalcolithic (named for the discovery of copper in Anatolia, ie. Turkey) -- the defining social advance was the move from agriculture to trade. The discovery of copper meant that for the first time a commodity existed for which there was no good-enough local substitute. This created the trading class as we generally think of it today -- as a dedicated service occupation; and that in turn made large cities and thus empires possible, rather than tribal towns. (It's worth asking what the supposition of alien intervention adds to this scenario, if your seriously suggesting that.)
Otherwise, if you think about the kind of writing needs such a society would have (and this is only 5,200 years ago, not your 6,000) it's fair to ask what you would expect them to write, or what, of their writings, you would find interesting to read, even if it had survived. If you want to read something within 1500 years of that time, then try the Enuma Elish or the Laws of Hammurabi (this oldest example of the test for a witch is in there -- it's an interesting read). All these docs are available online.
Apparently they're now called vertically challenged galaxy overlords.
Think of the little people...
And as for destroying our own history - there are far more traces of civilization than written materials. Technology leaves evidence. We have found tools and weapons and such from hundreds of thousands of years ago. Anything more complex would not only survive in and of itself, but the infrastructure to create it would leave parts laying around. Don't bother talking about wars and catastrophes. Besides the fact that they don't erase everything, they leave their own evidence behind.
Sorry for the fun story, but we're natives. Our ancestors have been here on earth for over three billion years.