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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
20 45,247
HELPFUL DESCRIPTIONS. a : semimajor axis For elliptical orbits, the semimajor axis is half the length of the...
May2-10 02:49 PM
45 67,842
Have population II stars been observed or speculated to have planets?
Oct3-08 11:21 AM
2 2,119
I was thinking about light and baryonic matter. My understanding is that stars emit light by essentially converting...
Oct2-08 03:47 PM
10 1,440
My first post on this site, been reading for a while but joined up today so please bear with me :) I've got an...
Oct2-08 01:25 PM
2 2,520
How fast does the planets move away from the Sun ? (The moon moves 5 cm per year)
Oct2-08 02:46 AM
0 1,984
I heard that for one baryon there are 10^9 photons exists in this universe..i want to know how did they calculate? is...
Oct1-08 09:12 PM
5 3,684
If light always travels in a straight line, the only time light appears to be bent is when a large gravitational field...
Sep30-08 08:25 PM
3 1,723
If a black hole really does have hawking radiation can in theory the black hole be stable. What I mean by this is...
Sep30-08 07:36 AM
3 2,004
I'm currently looking at Metric for the Rain Frame in 'Exploring Black Holes' by Taylor & Wheeler (page B-13) and...
Sep29-08 02:55 AM
2 1,825
Stars seem to occur in almost every color, from red to near violet, but not green. Why are there no green stars?
Sep28-08 02:04 AM
Vanadium 50
1 1,249
Does a Schwartzchild blackhole have a singularity at its center?
Sep26-08 08:29 PM
9 1,893
Hi, Let's say we have a white dwarf accreting material from a giant partner. How long would it typically take for...
Sep23-08 09:22 AM
3 2,266
arXiv:0809.3730 Title: Experimental Tests of General Relativity: Recent Progress and Future Directions Authors:...
Sep23-08 02:22 AM
0 1,178
It's my understanding that everything in space is in some sort of "free fall", which is pretty much what an orbit is....
Sep22-08 06:03 PM
37 6,884
From what I understand, from a frame of reference outside a black hole, it takes an infinite amount of time for a test...
Sep21-08 01:42 PM
2 1,391
Why do we ever get Einstein crosses? I realise it is because the alignment is not right, but why do we get a cross...
Sep21-08 08:03 AM
2 1,420
Link Where are they going get anti-matter and is this even possible with technology we have now
Sep20-08 06:33 PM
38 10,542
Hello everybody: I've got a few questions that I could not find answers to, so perhaps someone on this forum can...
Sep19-08 09:38 AM
Jonathan Scott
1 1,924
Hi all, Recently I came accross an interesting question: "...Why do astronomers attribute the observed Doppler...
Sep19-08 04:14 AM
6 1,933
i've just been reading about dark energy on a site, and it seems it's quite a riddle at present. it stated that the...
Sep18-08 11:00 PM
1 1,294
Hello, I would like to define (calculate/plot) the radius of collapsing interstellar cloud as a function of...
Sep18-08 09:28 PM
2 1,598
What an ambitious emerging field of research! Anyone else as into this as I am? ...
Sep17-08 07:15 PM
0 1,100
Sorry didn't see this forum. I need some help with calculating simple theoretical parallax error:...
Sep17-08 05:22 PM
1 1,223
In discussions of how we infer the existence of dark matter, it always feels like people gloss over how exactly we...
Sep15-08 10:12 PM
4 2,422
are there two points or one in an elliptical orbit where the speed is equal to the speed of a circular orbit at the...
Sep15-08 07:51 PM
8 3,636
Dear all, As an outsider to the field of asteroseismology, can someone please give me a rough idea has to how large...
Sep15-08 09:23 AM
0 1,144
According to an article on the CERN website 'dark energy' is detected by its 'gravitational effect': Most of the...
Sep12-08 07:10 AM
5 1,454
Is matter going into a black hole the same as antimatter leaving one? This has confused me for a while... ...
Sep11-08 04:49 PM
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First question: According to Hubble's Law, the redshift observed by distant galaxies are proportional to their...
Sep10-08 09:34 PM
10 1,603
Hello, I am new to this forum - and impressed with the posts. I have recently developed an addiction to astrophysics....
Sep9-08 12:41 PM
5 1,299
Suppose for a senond that the only objects in the entire univesre are 2 stars, both about as massive as the sun. ...
Sep9-08 11:31 AM
Count Iblis
16 2,821
While Gm/r^2 seems to apply only for gravitational acceleration towards spheroids, what would be the equation for...
Sep8-08 07:02 AM
5 3,075
I heard that dark matter could be the CMB mass corresponding, but I am not satisfied from that. What about this?
Sep5-08 11:46 PM
3 1,191
Hi, In a few journals I've come across the term "centimeter continuum emission" - e.g. 21 cm continuum emission....
Sep4-08 10:11 AM
1 1,293
I have been reading all of the previous threads on this topic, but they are all locked or in some strange stasis...
Sep2-08 07:45 AM
1 1,335
Where could I find the spectra of most elements on line? I would expecially the He 2 spectrum, the Be and the B ones....
Sep1-08 09:57 AM
1 1,182
I've seen some measurements of supernovae, and they often mention a ring that's expanding. I can follow that. What...
Aug30-08 05:54 AM
1 2,835
I've recently come across some doubters as to the existence of dark matter. If you find yourself among that group,...
Aug28-08 06:31 PM
4 1,959
(This was originally posted in Why mass causes space to bend but I started a new thread as it was going slightly off...
Aug28-08 12:35 AM
0 1,327
a black hole is basicaly a massice rip in space with an invisible gravity source. a wormhhole is a rip in time and...
Aug27-08 06:50 PM
14 2,826 This came out at the...
Aug25-08 11:14 AM
6 2,702

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