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To help me in understanding this procedure, I read the fifth chapter of THE DETERMINATION OF ORBITS by A. D. Dubyago,...
Apr22-12 12:10 PM
Drakkith
20 45,210
HELPFUL DESCRIPTIONS. a : semimajor axis For elliptical orbits, the semimajor axis is half the length of the...
May2-10 02:49 PM
Jenab6
45 67,799
Next year the Hyabusa spacecraft will return to Earth from the asteroid Itokawa. Inspired by this, you are required...
Oct9-09 12:34 AM
dewy
4 1,746
I would be grateful if someone could point me to a description of how a sphere of freely infalling matter ---- say...
Oct8-09 06:57 AM
oldman
22 3,005
I have been thinking about this for a few weeks and can not come up with an answer. As I understand it a black hole is...
Oct6-09 10:37 PM
Chronos
14 1,643
A very basic question (I hope this is the right place for it). A distant star emits, say, a high-energy x-ray. Due...
Oct5-09 03:07 PM
map19
11 3,456
In terms of physical dimensional size, what are the measurements a black hole must fit in order for it to actually...
Oct5-09 08:20 AM
Wallace
12 1,448
If Gravity is constantly pulling galaxies toward each other, why are they accelerating away from each other???...
Oct4-09 06:05 PM
DaveC426913
38 4,200
Two citations referenced by Wikipedia with respect to General Relativity models for spinless charged neutron stars,...
Oct4-09 09:09 AM
Orion1
3 2,407
Consider, if it were the case, that the plasma torus left in Io's path as it orbits Jupiter followed the same orbital...
Oct3-09 04:45 PM
Pennarin
2 1,669
Earth has a tilt to it about 23.439281° to -23.439281° from the Tropic of Cancer to the Tropic of Capricorn. The tilt...
Oct3-09 06:11 AM
Philosophaie
1 2,366
When two black holes collide, do the singularities orbit each other, does one evaporate into the other, or is...
Oct2-09 04:34 PM
pzona
31 3,056
Could somone explain in simple terms the Strong Equivalence Principle and give some sort of example. I now the weaker...
Oct1-09 12:01 AM
gregstanley
0 855
I'm doing an undergraduate research project this term on some modified theories of gravity, and I need some...
Sep29-09 07:31 AM
Wallace
1 1,057
I need science fair ideas... and quick! I love math and the universe so this was the first place I came looking for...
Sep28-09 06:03 PM
chroot
8 1,928
Dear all I've read that some "Multiverse" theories suggest that there are infinite number of universes .. But they...
Sep27-09 09:59 PM
m-theorist
10 1,357
I am having a hard time thinking about the perservation of the second law of thermodynamics in black holes. If we...
Sep27-09 02:52 AM
Orion1
3 1,840
If a neutron star accumulate materials from its companion star ,then it's mass exceeded Tolman–Oppenheimer–Volkoff...
Sep26-09 09:04 AM
Chronos
4 1,471
Stars eventually die because they use up their fuel right? If all of this fuel was to be used up, would there be no...
Sep25-09 04:29 AM
qraal
4 918
I have just came up with the following idea which can, with the proper equipment and technology, be applied in space...
Sep24-09 07:08 AM
Cosmicon
10 1,562
I'm wondering how realistic it is for a 50 solar mass star to have a core temperature of 3.14*(10^7) K. This isn't...
Sep23-09 06:15 AM
qraal
1 3,271
I understand that astronomers often locate planets orbiting other stars. They do this by detecting the "wobble" of a...
Sep21-09 05:49 PM
bombadil
6 1,382
consider two planets, planet X and planet Y with masses, Mx and My separated with distance, D and they orbits about...
Sep20-09 11:28 AM
jambaugh
2 1,293
Hi, I'm a writer and I've just started researching a story about astronomy. I'm not a physicist (actually I'm a...
Sep20-09 12:11 AM
marcus
3 1,797
That is, does gravity travel instantaneously? Have we ever been able to measure the speed with which 'gravity travels'?
Sep17-09 08:15 PM
Sorry!
3 1,661
I've just started learning about Hubble, Red shifts, and how we measure the universe's expansion. It seems that he...
Sep17-09 07:25 PM
pulsexx
1 1,090
The general theory of relativity leads to the conclusion that the fabric of space time is ever expanding . This has...
Sep17-09 12:59 PM
Axuality
27 2,861
Do any of you know which article(s) are used to do the "expected" rotation curve for galaxies, that always seem to be...
Sep16-09 12:37 PM
Hepth
10 1,734
How do we determinate the mass of stars (or planet) in other solar systems?
Sep16-09 03:28 AM
Chronos
7 1,637
Like the title says, I'm wondering what exactly is the definition for radio luminosity. A search on Google doesn't...
Sep15-09 09:00 PM
bombadil
1 2,504
http://pirsa.org/09090028/ Video lecture by Eliot Quataert, a young guy at UC Berkeley expert on GRBs. He brings the...
Sep15-09 11:12 AM
marcus
0 956
Hi again :) I need some help in a not difficult question (I hope). I would like to know how other planets can...
Sep15-09 08:32 AM
D H
4 2,541
I was wondering about the possible surface g of this giant rocky planet, and I found this one origin hypothesis on...
Sep15-09 08:08 AM
Researcher X
2 1,064
I understand some of the basic concepts of curved space, flat, positive, negative, spheres, saddles, etc. In flat...
Sep14-09 12:08 PM
tiny-tim
3 1,023
How does one convert measurements in radio astronomical terms to temperature (Kelvin)? Specifically: Penzias &...
Sep13-09 08:44 PM
smallphi
1 1,436
Let say gravity suddenly decreased 10%, - for instance due to tidal friction etc... How fast would a planet...
Sep13-09 02:29 AM
Bjarne
7 1,264
Coalescent of two white dwarfs can produce supernova? What kinds of supernova?
Sep12-09 09:06 AM
magnetar
0 1,079
In the perception of General Relativity a Black hole can form in wich anything (including light) is trapped inside the...
Sep12-09 06:05 AM
robheus
3 1,672
The 'measurement' of the radial expansion of the moon's orbit is 3.8 cm/yr...
Sep10-09 07:25 AM
bwana
3 1,155
How many neutrino emission mechanism, that causes the cooling of star, are there in neutron star? And How, what...
Sep10-09 05:15 AM
stevebd1
3 1,582
Here is an excerpt from Wikipedia The Shapiro time delay effect, or gravitational time delay effect, is one of the...
Sep10-09 03:38 AM
Nickelodeon
0 1,136
I'm trying to understand the mathematical methods of computing the atmospheric trajectory of a meteor for two or more...
Sep9-09 05:23 PM
solarblast
0 1,160

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