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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
Mass != weight
For a while there I was worried it had dropped down to 1 billion years.
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
The Earth's Solar System is located some 28,000 light years from the centre of the Milky Way. At that distance, the new measurements show that the galaxy is rotating at a speed of 965,600 km/h, compared to previous estimates of 804,672 km/h, the astronomers report.
965,600 km/h = 268 222.222 m/s or about 1/1117th of the speed of light...
But how do you calculate the rate of rotation and mass of a galaxy that you're in? It's mind blowing that we can actually do that.
I dreamed of Freud: What does this mean?
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.
I did a study.
1. Three Musketeers is the most voluminous.
2. Snickers is the densest.
3. Milky Way resulted from collision between high energy caramel particles into a Three Musketeers bar. And a new sub layer formed under the chocolate strata. The caramel particles could not penetrate the nougat.
4. Milky Way Dark has the most dark matter.
5. Mars has the biggest nuts.
WhatMeWorry!!
I think the article oversimplifies. The Milky Way doesn't rotate as one single piece. It's made up of billions of stars (duh!) which revolve around the center at different velocities. So, the question is, is the quoted speed the speed at which the Sun revolves around the galactic center or the average speed of the arms (which move much slower than the stars)? Maybe more later if I can find the paper on arxiv.org
... should have used low fat milk...
Oh no! I better not forget to turn of the oven!
dont_forget
... or maybe I'd better just slow down on the brandy.
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.
Whoa, for a moment I thought you said _million_ years. No need to panic, people.
...omphaloskepsis often...
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
Do you mean there is a problem with gravity in the future?
Fight Spammers!
Forgive the possibly stupid question, but since km/h is a measure of linear speed, is that saying that we're traveling at that speed or is the edge of the Milky Way moving that fast?
It means exactly what it says. Our Solar System is rotating at 965,600 km/h. We aren't at the edge of the Milky Way anyway as the artist's rendering on the article page shows so it isn't the latter. The "At that distance" phrase is referring to the Solar System's distance (28k light years) from the center of the galaxy. Since the Milky Way isn't being torn apart the outer edges of the galaxy are rotating faster than the inner core (outer edges have to move faster because they have more distance to travel) correspondingly to keep up with the inner core. This is similar to a CD in a CD drive. Since it is a solid material everything moves at the same time however the outer edges move at a rate that is faster than the inner edge. That is the angular velocity however that is being measured. You rotate it fast enough (as in an episode of Mythbusters) and the CD flies apart. I hope that makes sense.
this nation, under God, shall have a new birth of freedom. -- Lincoln, Gettysburg Address
The Milky Way!
BTW: you should see Luis Buñuel's movie of the same name:
Incontrollable Beauty
NO SIG
If that galaxy is more dense than ours, then it would also have higher gravity, correct? So it is possible for Sum of Mass to be nearly equal, yet our sum of weight would be much lower. I guess if all galaxies are orbiting some super distant super mass, and thus we had some weight related orbital decay, this discussion might matter?
Does this mean they'll take the candy out of the vending machines since it's obviously leading to obesity on a galactic scale?
-- Fugacity: Confusing chemists since 1908
some how i just know this is because of global warming!
If you mod me down, I will become more powerful than you can imagine....
"the Milky Way is rotating at a speed of 161,000 km/h faster than previously thought."
Units converted from radians/mole
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.
Well he did win. Fat guy in ICU (unless he dies from the gunshot) still beats a 65 gr slug in a evidence baggie.
You know an astronomer has found an unusually accurate measuring technique when the error bars get as low as 50%. Now that best value for the mass of the Milky Way has 1-sigma error bars of 50%, I'm glad to be able to say with 95% statistical confidence that its mass is greater than zero. On the other hand, for the "glass is half empty" folks, there's still a 5% chance that its mass is negative.
Find free books.
In what universe are those rules true? Certainly not this one.
The closer we are to the galactic center of mass, as measured in terms of the centers attraction for us, the higher the gravitational pull toward the center, and the faster we have to go in order not to fall in in a few million years. The stars and other materiel 10x farther out, have required orbital speeds much lower to sustain a constant orbit. This is the reason that most galaxies are spiral shaped, and one can say with 100% certainty which way its spinning because the inward ends of the spirals always point in the direction of rotation.
Of course, if the density increases linearly until things are less than a light year apart near the center, conversely the majority of the gravitational mass is outside, and the orbital speeds can begin to fall.
That scenario is not for most galaxies, un-realizable due to most galaxies having a 50 to 2,000,000 sun mass black hole at the center, and for the Milky Way, we are no exception. I don't recall the mass estimates for the invisible Sag B, which 'Sag A' orbits at a good relativistic clip, but lets just say its a big one and let it go at that.
The article did not specify where in the galaxy that speed was measured, but it makes common sense that they were referring to our location 28k light years out from the center. Had they been referring to some location in an outer arm that was 10x farther out going that fast, then by the time it got inward to us, it would be a relativistic velocity indeed.
2-3 billion years? I'll never make it!
Milky Way heavier than thought? Maybe it's your mom.
Zing!
IWARS.
People, in general, disappoint me. Politicians even more so.
OH MY GOD, I WAS GOING TO HAVE KIDS, I was gonna have a great life! I may win the lottery next week! How am I going to live knowing that my great*10^7 grandkids may be killed in a tragic intergalactic traffic accident?
OK, so now that the galaxy is heavier/massive. Do we still need dark matter to explain how it works?
Undetectable Steganography? Yep, there's an app fo
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.
It seems like whether the Milky Way or Andromeda is bigger changes every couple years, as this paper or that paper claims a measurement showing one or the other is actually a lot bigger than we all thought.
We used to think the Milky Way was bigger (and before that, thought Andromeda was bigger for the longest time), and then recently we got some evidence that Andromeda was actually bigger after all. And then there's this piece about the Milky Way actually be bigger after all.
Me? I'm going to sit back and let the scientists figure it out for a few more decades before deciding. All we really know is that Andromeda and the Milky Way are by far the two biggest galaxies in our Local Group, and they're probably close enough in size to make figuring out which one is really bigger a bit tricky.
Now I see why they are running all those commercials about 3Musketeers being 45% lighter.
Aw, crud. There go my plans.
Statistically speaking, you will die.
If you don't plan on what happens after that, someone else will (no pun intended).
Planning on something isn't the same as wishing for it.
As for me, WRT "the singularity"? If I could upload "myself", would I? I don't know. Probably. But if you think about it, "you" don't get to go, only your "branch/copy" does. Are you that selfless? What if it costs money? Are you willing to pay for "his" immortality? AFAIK, the first sentence stands alone.
This issue is a bit more complicated than you think.
Clarification: "the collision" is referring to the galactic collision, not stellar collision.
Table-ized A.I.
I've been noticing how everyone is getting heavier (except Steve Jobs). Apparently, this epidemic has reached galactic proportions. Of course, we should have suspected the Milky Way to be fattening.
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.
Did you see the bullet afterward?
Respect the Constitution
Apparently the fluffy nugat filling isn't as fluffy as previously claimed.
If it's not Consolidated Lint,it's just fuzz!
Speed: if you know a constellation of stars is in our galaxy, then you can track it's movement speed. Especially since we have software that'll give the position of constellations right back to egyptian times, etc.
Mass: they're working this out based on the rotation speed.
Remember that the reason dark matter supposedly exist is because scientists calculated the weight of the visible matter in the entire universe and said "well that doesn't match up with the energy/gravity" so they make up some imaginary object to make up the difference. And then a couple years later OMG I guess we were 50% off of the mass of the milky way, oops. If they can't even measure our galaxy properly, then dark matter probably doesn't exist because they're just calculating it wrong. Either that or it's literally regular matter that has almost no light bouncing off it cuz it's too far away from a light source.
Google's Super Secret Search Algorithm: SELECT @search_results FROM internet WHERE @search_results = 'good'
Does that mean that we age slower compared to the people in Andromeda?
"It is our choices, Harry, that show what we truly are, far more than our abilities." -- Prof. Dumbledore
The Inhibitors have to speed up a bit.
100 billion stars * 5 usefull planets?
500 billion * 200 trillion dollars = WERE RICH!
We can offer plots at 2% rates.
Liberty freedom are no1, not dicks in suits.
Get it right!
greg, REMEMBER ED CURRY!!!
Not heavier.
Damping absorbs vibrations. Dampening is caused by moisture.
Comment removed based on user account deletion
Does anyone have a citation for an actual peer-reviewed article on this? Because I'm not particularly inclined to believe this random article from somewhere just on its own . . . and it doesn't seem to include a citation to anything.
That was my first impression, too. As in: "Milky Way Heavier Than Thought". How does one weigh a thought, anyways, and isn't Milky an adjective? And how much does an adjective weigh?
I wish I had a kryptonite cross, because then you could keep Dracula and Superman away.
As "fun size" and "bite size" and decreased density of the malt nougat reduce our bar per dollar, its nice to know that its not as bad as it seems.
I for one welcome our caramel-covered malt-nougat overlords!
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
> It means exactly what it says. Our Solar System is rotating at 965,600 km/h.
That's... ambiguous, at best. km/h is not a unit of angular/rotational velocity.
Cut that out, or I will ship you to Norilsk in a box.
Ah, you jest. But: http://astroprofspage.com/archives/117
The world is made by those who show up for the job.
nt
He rounds alot in the song he is fine.
It certainly wasn't in ICU though.
If you can't see the value in jet powered ants you should turn in your nerd card. - Dunbal (464142)
/dev/null
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
Remember, the Solar System is only a theory, just like gravity and chemistry. We need to start teaching kids about the alternatives!
Does this change any lyrics in the Galaxy Song?
It certainly wasn't in ICU though.
Well yeah, no insurance. Have you tried getting a policy for a bullet? The rates are insane!
The enemies of Democracy are
I think not. So I don't get it. Why does greater mass than we thought, mean impact with another object sooner than we thought?
Yours Sincerely, Michael.
It's time to go on a diet again.
Know your pads. One time pad: good for cryptography. Two timing pad: where to take your mistress.
Doesn't the idea of galaxies colliding conflict with Hubble's discovery that the Universe is expanding? I thought that no matter where you were in the universe, everything was moving away from you. I remember examples with a balloon and also raisin bread. If Hubble is right, then shouldn't Andromeda be moving away from any vantage point in the Milky Way (and anywhere else in the universe for that matter)?
Also, time is a cube, so there are actually four simultaneous days which our Earth passes through as it rotates through a single 24 hour period.
Sorry, it's an interesting point you make but it just felt like the right thing to say.
So, how does this 'bollocks up' Eric Idle's Galaxy Song?
@peetm
So, who else here thinks that all of the space around us with it's planets etc. is just a tiny molecule of some really big "thing". Just imagine that maybe there is a real giant sitting behind his computer...typing on his keyboard which in fact is composed of what we know as our galaxy? Did I explain my question clearly enough? :) anyone else here shares my opinion...?