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Comment Re:Actual discovery: Mass of one such galaxy (Score 4, Informative) 105

The are probably using mean red shift to measure the distance. The collective light of all the stars in the galaxy are together red shifted a certain amount that's a direct indication of how far away the galaxy is due to the expanding universe. The farther away the galaxy, the more red shift there is. And, one can measure speeds due to red shift very very accurately, down to tens of meters per second. The error bars here are that the far away galaxy can have a local movement that's unknown, but if the galaxy is a part of a cluster, that factor can be measured and accounted for. This is the most common and simplest way of measuring distance to galaxies, invented by Edwin Hubble in the 30s. The second most common is using Type 1A super novas, but they have to appear to be used, and.. that's a fluke incident, more commonly used to calibrate and confirm the red shift measurements.

Comment Re: Actual discovery: Mass of one such galaxy (Score 4, Informative) 105

There's no way you could use parallax effect to measure distance on a galactic scale. We can measure about 1 milli arc-second with space based telescopes, and that accounts for a distance of 1000 parsecs, i.e. ~30.000 light years. Hence we cant even use it for measuring distance to all stars within the Milky Way.

Comment Late to the game: Swift (Score 4, Interesting) 113

Swift! Apple just released their new programming language as OpenSource and it is the future for all development for Apple's platforms. The scope for Swift is enormous: use it for everything from operating systems to scripting. Swift builds upon their already open development technologies: llvm, clang and lldb and Swift will fit in nicely here.

Comment Magnetism (Score 1, Troll) 32

Studies have also shown that magnetic forces might count for the majority of clumping of matter in sizes smaller than regular rocks. On those scales gravity doesn't do much, but magnetism can do plenty. And it wouldn't be strange for protoplanetary matter is magnetized since it's whirling around in the Sun's magnetic field.

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