# Tag Info

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Yes, indeed there is a correlation between warm regions of the CMB and galaxy clusters. The CMB fluctuations depends on what scale of perturbation that you look at. For large scale perturbations, the opposite to what we expect is true. On the large scales, an overdense region at the time of recombination results in a cold spot in the CMB map. This is ...

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The equation $L_i=L_*(M_i/M_*)^{3.5}$ relates the mass ($M_i$) and luminosity ($L_i$) of other main sequence stars to the mass ($M_*$) and luminosity ($L_*$) of the Sun. It is not applicable to other types of stars such as red giants. The question says you calculated "the mass-luminosity ratio $M_*/L_i$ for each". Since $M_*$ (the Sun's mass) is known, ...

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Gravity on Earth uses two concepts, one is the radius (R) of earth and the other is the distance (h) from the surface of the Earth. Really, approximating the Earth to be spherical and uniform, it is just one distance, the distance from the center of the Earth that matters. $F = G \frac {M_{Earth} m}{r^2}$ where $r$ is the distance from the center of ...

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Light from beyond the Hubble sphere (the place where recession velocity equals the speed of light) reaches us daily. I'm not good enough a physicist to come up with a nice layman's explanation for this fact, but it might help to think in comoving coordinates: This is a special coordinate system where the coordinate grid expands with space, ie even though ...

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I do not know if the following answer can explain each and every observation, but here goes : The expansion or moving away of galaxies is dependent on the distance between them, if something is moving away at some rate then previously since it must have been close, it must have moved away at a slower pace. While making astronomical observations, we are ...

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We know that some galaxies are moving away from us faster than the speed of light and we know it by measuring the redshift, but how's that possible? The following papers give good explanations: http://users.etown.edu/s/stuckeym/AJP1992a.pdf http://arxiv.org/pdf/astro-ph/0011070v2.pdf In summary, Hubble Law: $v = H(t)D$, where $v$ is recession ...

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Question: How many stars are in the Milky Way Galaxy? Answer: As many as there are! Why this answer? Answer: Even the stars that are close to us are eons older than when their light approximately began to journey toward all directions including Earth. Unknown & thus far unprovable amount of celestial activity continues from when ever it ...

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Black holes pull matter in thus creating a pulling of matter or rotation (gravity) force that matter rotates or spirals around thus creating our shape form and rotational direction of our galaxy. If our sun doesn't die first then yes one day we will be pulled to the center of our galaxy. Every galactic year our solar system speeds up and grows closer to the ...

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The Milky Way is receding from the members of the Hydra-Centaurus Supercluster. The Hydra cluster has a red shift of 0.0548. The Centaurus cluster has a red shift of 0.0114. The Norma cluster has a red shift of 0.0157. The local group is and will continue moving away from the Hydra-Centaurus Supercluster.

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It's because of Conservation of Angular Momentum. When all these systems are in the process of creation, all motions not existing in the same horizontal plane cancel each other out which confines them into that plane. The system continues to exist that way due to conservation of Angular Momentum.

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it is because of the way the solar system formed from a cloud of gas. the molecules of gas (mostly hydrogen) were pulled together by gravity which formed a spinning disk of gas around our sun, thus forming the planets all on the same field.

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To the original poster: You appear to be operating under the "hollywood" misconception that a black hole somehow "sucks harder" than the same amount of mass in a non-black-hole form. However, this false "black holes produce an enormous sucking" misconception is one of the many, many concepts of physics that "hollywood" gets totally wrong; a black hole of a ...

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