Some astronomers spend their careers peering at and discovering distant galaxies; Sukanya Chakrabarti is trying to discover one a lot closer to home. Chakrabarti, a post doctoral fellow and theoretical astronomer at UC Berkeley has developed a mathematical formula that she says can identify and measure small, "dark" satellite galaxies orbiting larger galactic disks, and she thinks she's found an undetected one just on the other side of the Milky Way from Earth, obscured from our view by the dust and gas in the galaxy.
Well, it's also obscured from our view by the fact that it's mad mostly of dark matter. Dwarf galaxies are thought to orbit many large galaxies like the Milky Way, though we can't readily observe them because they are too dim to see or are dominated by dark matter. Chakrabarti's method observes them indirectly by analyzing the ripples in the hydrogen gas distribution in spiral galaxies and inferring the position and size of the satellites.
Chakrabarti calls her hidden galaxy "Galaxy X," a tip of the hat to "Planet X," a tenth planet that was once thought to be orbiting beyond Pluto due to erroneous observations of anomalies in the orbit of Neptune. Unlike Planet X, Chakrabarti and a few colleagues say her mathematical model shows that Galaxy X is there, just 300,000 light years from the galactic center (the galactic radius is about 50,000 light years). Another astronomer has even applied for time on the Spitzer Space Telescope to peer at Galaxy X in infrared wavelengths.
The team has reason to have faith in the numbers; in collaboration with partners at the Canadian Institute of Theoretical Astrophysics, it looked at a couple of galaxies already known to have satellite galaxies that have been characterized through astronomical observation. Their mathematical analysis, when applied to these galaxies, correctly predicted the positions and masses of their satellites. Chakrabarti says her method should work for satellites as small as one one-thousandth the mass of the host galaxy.
While they wait on telescope time, the team plans to refine Chakrabarti's formula by studying a larger sample of galaxies and their satellites in an effort to mitigate the appearance of false positives. If the formula holds up, it might not just be a tool for locating and characterizing dark satellite galaxies, but could become a tool for testing dark matter theories and learning more about the elusive stuff that, in theory, makes up most of the universe.
Dark matter here we come.
"it’s also obscured from our view by the fact that it’s mad mostly of dark matter."
The dark-side tends to use anger as a weapon, that probably explains why it's mad.
I really really don't understand dark matter.
Its existence is theorized because according to observational astronomy there isn't enough matter in the universe to make E=MC2 work. Well going back to 6th grade I remember algebra told me that A = b + c.
If A is the size of the universe, and b is matter then c must be anti-matter according to most cosmologist.
But what if B is wrong? What if we are not measuring correctly? Seems like the simplest answer. Certainly more reasonable then adding dark matter, dark energy, String Theory M-Theory, 11th dimensions....
Where can I pick up my Nobel prize?
matter + antimatter = 0
and size /= amount of matter?
sorry your analogy makes no sense.
it's not the size of the universe that implies dark matter exist its the fact that if you take everything we can see (what makes light and what reflexs it) only makes up 20% of the mass needed to work the way it does.
we can also see the effects of dark matter's in gravitational lensing of background light, rotational speeds of galaxies and temperature distribution of hot gas in galaxies.
all of these clues point to there being alot of something we can't see but has gravity and we call that dark matter.
Actually i agree with @dodger why cant dark matter be antimatter, safely separated by distance in time,i mean whole periodic table ,planets,stars,n galaxies made out of antimatter and not detectable by our normal matter instruments.
May be that also explains the high energy bursts we see here n there,which can not be explained.may be they are because of collision between matter and antimatter(dark matter) worlds..
why, mr. Anderson, why, why do you persist?
Because I Choose To...
simple answer is because antimatter acts just like normal matter in every way (just with the poles reversed) it reflexs light and gives off heat meaning we would see it. while dark matter only interacts through gravity, it's what gives our own galaxy the mass it needs to hold itself together. but it can it can pass right through a planet or person and you'd never know.it can even pass through itself with interacting other dark matter. so there is no separation by "distance in time" to keep it from interacting with matter.
so if the theories are right dark matter is in you house right now, heck its inside you and I at this very second most likely . now seeing as you and I haven't exploded we can say its not antimatter.
Could be matter was and can be created from dark matter. Good theory as any. The so called big bang could have been this event. For some reason God decided that some of this DARK MATTER had a spontaneous or planned degeneration into 3/4 dimensional matter. Since there is no longer a balance of dark energy and dark matter in this region of existence, the amount of dark energy is greater than the amount of dark matter. We as 3/4 dimensional matter exist in the same space as this dark matter and energy and are affected by it. Thus the inbalance of the FORCE keeps the visible universe expanding This due to an greater amount of dark energy in this area. Where is Yoda? We need to rebalance the farce.
Could it be this dark matter/energy is what we know as the spirit world? If so it would explain a lot of things. The Bible states that all things of the flesh are first manifest in the spirit. It interacts with us but we can't quite put our fingers on it.
@ dex drako; So, is it true that we are going on the supposition that dark matter is affected by gravity? AND that it can 'flow through itself'? Because it seems to me that if it is affected by gravity, AND can exist in the same space-time as normal matter; that we should therefore almost never see it in evidence at all. Wouldn't it be bound by gravity to the largest gravitational body in any locale unless or until that body is destroyed? If it can flow through itself as well, then wouldn't the actual place occupied by the dark matter be very small, and bound literally at the point of highest emitted gravity?
Did God really decide that?
Dark Matter is everything outside of our atmosphere. Obviously, besides quasars, stars, nebulae, etc. Everything that is nothing. Where there is nothing, there is only dark matter. Think of it as waving your hand through the air. People that don't think outside the box would say they're not touching anything, when actually they're touching oxygen, nitrogen, CO2 and everything else your local air supply would contain. Question: Say you were traveling through space in a capsule, powered by nothing but inertia, if you were to leave the capsule, would you travel along side the capsule with the same inertia you had inside, or would you be left behind? If you were to wave your hand in space, would you feel anything?
I guess what I'm trying to say is if Dark Matter makes up 70% of the known universe, wouldn't you think its all that darkness we see when we look up in the night sky?
On another note. I believe gravity only works strickly with dark matter, nothing else. Space is a sea of dark matter, and gravity is the whirlpool pulling the water to it. You get caught in the waves, you're in for one hell of a ride. But of course, water would cause drag, dark matter would not.