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Milky Way Heavier Than Thought, and Spinning Faster
An anonymous reader writes "The Milky Way is spinning much faster and has 50 per cent more mass than previously believed. This means the Milky Way is equivalent in size to our neighbor Andromeda — instead of being the little sister in the local galaxy group, as had been believed. One implication of this new finding is that we may collide with Andromeda sooner than we had thought, in 2 or 3 billion years instead of 5."
At least now we don't have to worry about our sun going nova, we'll all die in an intergalactic traffic accident first.
..on my Zune
One thing that is great about science is that it does have a way of eventually finding errors and correcting them in the face of new evidence.
As far as galactic collisions are concerned, we are in no immediate danger. 2-3 Gy vs 5 is an academic exercise, as the Sun will most likely increase its output sufficiently by then to boil off the Earth's oceans anyway,
Besides, the density of a galaxy (outside of the core) is so low that the chance of a stellar or planetary collision is negligable anyway.
Or, by then, we would have the technology to detect it and either deflect it or GTFO of the way anyhow.
Still, it is nice to know we're not in the pipsqueak galaxy. Hoorah!?!?
Well, that'll show those Andromedans not to attack "smaller" galaxies. Now who's laughing! We will plunder their mass (while watching colateral ejected mass fly out).
oh well.. still leaves plenty of time to debate which is the most robust backup method after all then?
Thought I was drunk.
Good to know it was the milky way spinning all too fast.
NO SIG
Because it's on youtube. http://www.youtube.com/watch?v=dJRc37D2ZZY
Ugh. Sounds like scientists just discovered my last blind date.
__ Someday, but not this morning, I'll finally learn to use the preview button.
Actually the orbital velocity is (surprisingly) close to constant, as in most spiral galaxies. In fact, it is these "flat" (i.e. constant as a function of galactocentric radius) rotation curves that were some of the earliest evidence for dark matter.
That having been said, my guess is that the velocities quoted in the press release refer to the Sun's (or more accurately the Local Standard of Rest's) velocity around the Galactic center.
Couldn't find the paper on arxiv.org ...
Tell that to the fat guy who got shot with a rifle round. He has a 600,000% weight advantage, yet he's still in ICU on a respirator.
Fat man 0, Remington 1.
I hate printers.
"...the galaxy is rotating at a speed of 965,600 km/h, compared to previous estimates of 804,672 km/h, the astronomers report."
Anyone else think it odd that the previous estimate had six significant digits, yet was apparently off by ~20%?
I think my chemistry teacher would have taken off points for that one.
The odd thing is not the estimate (500,000 mph has one significant digit) but its conversion to km/h.
Twice as heavy! Talk about getting it wrong.
It's only a matter of time before the earth's age is readjusted to 6000 years!
I record my sleeptalking
Thank you, makes much more sense now. Agence France-Presse strikes again. They converted mph to km/hr VERY precisely.
965,600 km/h = 600,000 mph
804,672 km/h = 500,000 mph
Abstract of presentation (10aPT Tue Jan 6, if you are in Long Beach CA) is at http://tinyurl.com/9d5rec.
The visble arms of our galaxy's spiral aren't a fixed buch of stars clustered togther, it's a density wave that travels around the disk. Our solar system will pass in and out of various arms (eventually) as the density wave is travelling at a different speed to the actual rotation.