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| bio | website | |
|---|---|---|
| location | ||
| age | 21 | |
| visits | member for | 2 years |
| seen | May 9 at 22:17 | |
| stats | profile views | 111 |
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Jun 14 |
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What happen when two galaxies collide? @Cameron: The funny thing is that, as you said, although the stars themselves don't interact much (except gravitationally) during the collision, the gas and dust do interact, and sometimes form such "starburst" regions, like the Antennae Galaxy which you referenced. |
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Jun 14 |
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Could the earth have another moon? Thanks for the info. However, the ISS is usually between 350 and 400 km above the Earth's surface, yet it still needs periodic boosts every few months because of atmospheric drag. 100 km is nowhere near high enough to escape the Earth's atmosphere completely. |
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Jun 14 |
asked | Could the earth have another moon? |
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Jun 14 |
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Why does a black hole have a finite mass? Note that not all theories explain a black hole as a singularity. There are some exotic ideas out there, but in some cases the black hole is simply extremely dense, but not necessarily infinitely dense (but still dense enough to have an event horizon). The singularity arises from relativity. |
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Jun 13 |
answered | Recommend good book(s) about the “scientific method” as it relates to astronomy/astrophysics? |
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Jun 13 |
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What do the colors in false color images represent? To go along with both Eric's and Tigran's explanations, this image shows the color mappings of the famous image of the Eagle Nebula. Notice that the colors used (blue, green, and red) don't exactly match the colors they represent. A true color image, on the other hand, is very different (mostly red due to H-alpha). Still, your eye isn't sensitive enough to perceive this color. |
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Jun 13 |
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Does the Moon's core still contain significant heat? Instead of commenting on your answer, you should just edit it to include more info. |
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Jun 13 |
accepted | Calculations of apparent magnitude |
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Jun 13 |
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Calculations of apparent magnitude Good point on the bolometric luminosities - the B-V index of Vega is indeed quite low (listed as 0.00 on Wikipedia, actually). |
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Jun 12 |
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What frame(s) of reference are used to measure the rotation of the Sun around the galaxy ? This might be slightly off-topic, but as far as your mention of "fluid" rotation, have a look at this Wikipedia page describing density wave theory. It has some nice animations. |
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Jun 12 |
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What happen when two galaxies collide? Galaxies aren't mostly gas and dust. Most of their mass is contained in dark matter. Furthermore, most of the luminous mass is contained in stars. |
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Jun 12 |
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Shapes of galaxies This answer isn't very accurate. First of all, population III stars did not turn into supermassive black holes- they were perhaps larger than the largest of current stars, but not by much. Also, the supermassive black hole model is simply one idea of galactic formation. Scientists are still trying to see if the black hole formed before or after the galaxy, or if they formed concurrently. Finally, the explanation on why galaxies have their shape is wrong. There are multiple explanations, but each follow either a top-down or bottom-up approach. |
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Jun 12 |
answered | What frame(s) of reference are used to measure the rotation of the Sun around the galaxy ? |
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Jun 9 |
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Binary stars' apparent magnitude @Jonathan: No way. Stars are opaque to light- in fact, it takes an extremely long time (on the order of hundreds of thousands of years) for the light from the core of our own Sun to make its way out to the surface. It is only from the surface that they can propagate in the vacuum of space. |
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Jun 9 |
asked | Calculations of apparent magnitude |
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Jun 9 |
accepted | Why is the Ritchey–Chrétien telescope preferred in professional astronomy? |
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Jun 9 |
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What's dark matter and who discovered it? It'd also be good to note that Dark Matter is a proposed mechanism for a "scaffolding" through which galaxies form (or, at least, that's one form of the idea). It's good that you made apparent that Dark Matter hasn't been detected yet, it is simply our best explanation for certain observations that have been made. |
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Jun 8 |
answered | Binary stars' apparent magnitude |
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Jun 8 |
accepted | What are the various kinds of Cassegrain telescopes, and what benefits and drawbacks does each have? |
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Jun 8 |
answered | What is the name of our Galaxy? |
