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Search found 114 matches
- Mon Oct 08, 2007 1:08 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: 2 Million Galaxies; % of sky? (APOD 07 Oct 2007)
- Replies: 11
- Views: 3849
2 Million Galaxies; % of sky? (APOD 07 Oct 2007)
http://antwrp.gsfc.nasa.gov/apod/ap071007.html
How did they count the 2 million galaxies in the image? Did they count in a small square and extrapolate to the rest of the image?
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- Fri Sep 21, 2007 12:29 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: Deneb a supergiant? (APOD 20 Sep 2007)
- Replies: 1
- Views: 1366
Deneb a supergiant? (APOD 20 Sep 2007)
The blurb for today's (9/20) APOD says Deneb is a supergiant. So does the web site the highlighted link goes to. I always thought that the term "supergiant" referred to the next to last stage of a massive star's life, e.g., "red supergiant" or "blue supergiant". Is Dene...
- Sun Sep 02, 2007 1:47 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: 'Hole in the Universe'? - Possible Explanation (27 Aug 2007)
- Replies: 72
- Views: 33632
Re: " Hole in the Universe " ? - Possible Explanat
Maybe we have just located the Center of the Universe ? I have always imagined that if Big Bang occurred, then all matter would depart the center in a spherical shape and thus leave a void behind so that in fact the Universe would be a hollow sphere ! ..................and that we are located in so...
- Sun Aug 19, 2007 3:30 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: 'The Tail of a Wonderful Star' (APOD 17 Aug 2007)
- Replies: 10
- Views: 6711
Here is another APOD picture of Mira, taken by the Chandra x-ray telescope.
http://antwrp.gsfc.nasa.gov/apod/ap060722.html
Clicking on one of the highlighted links will give you more information about Mira.
http://antwrp.gsfc.nasa.gov/apod/ap060722.html
Clicking on one of the highlighted links will give you more information about Mira.
- Sat Aug 18, 2007 1:52 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: 'The Tail of a Wonderful Star' (APOD 17 Aug 2007)
- Replies: 10
- Views: 6711
Re: APOD 2007-Aug-17, The Tail of a Wonderful Star
(1) I was wondering about the mechanism that causes the variability. On Wikipedia ( http://en.wikipedia.org/wiki/Mira_variable ), it says the variability is caused by repeated contraction and expansion of the star. Mira's variability, from nearly invisible to magnitude 3.5, seems to be extraordinar...
- Sat Aug 18, 2007 12:52 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: 'The Tail of a Wonderful Star' (APOD 17 Aug 2007)
- Replies: 10
- Views: 6711
Given that the tail started forming at it's current start position (hypothetical) I calculate that the star has been leaving this trail for around 30,000 yrs based on it's current speed. Anyone confirm or correct this? Mira is a known double star and is also part of a Binary system If you click on ...
- Thu Aug 16, 2007 9:45 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: Picture perfect stary sky (APOD 15 August 2007)
- Replies: 17
- Views: 6726
Re: lights years of ignorance
LOL! I plead ignorance. I think that was sort of the point of my question. (And thanks, Don!) How are those starry clouds made visible via photography? Sort of a question--and I'd love an answer if there's one that is simple enough to explain here--and sort of expressing my awe. Good luck, Lee! It ...
- Thu Aug 16, 2007 9:37 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: Picture perfect stary sky (APOD 15 August 2007)
- Replies: 17
- Views: 6726
So, to get back on topic... :D I realy am very interested in getting into astronomy and specificaly into astro-photography. It's been an interest of mine most of my life (most of the 40 years of it), but I've just recently decided to persue it as a personal hobby. Any tips on hardware/software or a...
- Thu Aug 16, 2007 9:31 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: Picture perfect stary sky (APOD 15 August 2007)
- Replies: 17
- Views: 6726
- Thu Aug 16, 2007 9:07 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: Milky Way Galaxy
- Replies: 53
- Views: 14292
- Thu Aug 16, 2007 2:22 am
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: Famous and not so famous Cosmologists
- Replies: 35
- Views: 10305
http://www.light-science.com/alpher.html Ralph Asher Alpher authored his Ph.D. dissertation on the Big Bang theory in 1948. His mathematical formula brought into being the scientific theory of the origin of the universe. His paper said the universe occurred 14 billion years ago with a superhot expl...
- Thu Aug 16, 2007 1:58 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: Picture perfect stary sky (APOD 15 August 2007)
- Replies: 17
- Views: 6726
Re: how to take those pictures!
Really? Where are in the sky are you located now?Mary Nell wrote: I'm light years behind you
Mary, a light year is an unit of distance, not time. It drives me crazy when people use it for time. A light year is the distance light travels in one year, approximately 6 trillion (million million) miles.
- Fri Aug 10, 2007 3:24 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: God's Eye (APOD 03 August 2007)
- Replies: 25
- Views: 8471
I'm not certain exactly when the nebula came into being but if it's parent star exploded 10000 years ago, we have been able to view it for the last 9300 years. It will continue to expand, at most likely it's current rate, and in another 9300 years it will likely be twice its current size and half a...
- Wed Aug 01, 2007 2:56 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Tidal Tail of NGC 3628 (2007 Jul 27)
- Replies: 19
- Views: 6319
I don't think there's any case of a black hole being seen as a silhouette. They are just too small, even if one did happen to pass right in front of a star (which itself is unlikely). Black holes are detected indirectly, by the radiation emitted by gas and dust falling into them. Such radiation can...
- Tue Jul 31, 2007 1:41 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Tidal Tail of NGC 3628 (2007 Jul 27)
- Replies: 19
- Views: 6319
Black holes are transparent,arent they..?how can u detect them..?if there was a black hole..some of the pictures might be black due to the gravitational force that sucks all the matter around the black hole.. Hmmm..cant see it though..@@ If by transparent, you mean being able to see the background ...
- Sun Jul 29, 2007 1:40 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: The Tidal Tail of NGC 3628 (2007 Jul 27)
- Replies: 19
- Views: 6319
I doubt that is a black hole because what you called the corona of the star is just the overexposed image of the bright star spilling over to adjacent pixels. So the black hole couldn't be seen there. All stars except one (that I know of) can be seen only as points even through the largest telescope...
- Tue Jul 17, 2007 1:03 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: RCW 79 (APOD 14 July 2007)
- Replies: 1
- Views: 1418
RCW 79 (APOD 14 July 2007)
The explanation pointed out two other bubbles in addition to the large bubble in the Spitzer image. I espied a semi-circle of stars at approxmiately 12 o'clock position above the tight cluster of stars. Is it another bubble or just a coincident arrangement of stars?
- Sat May 26, 2007 1:25 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: Jupiter and the milky WaY (APOD 25 May 2007)
- Replies: 6
- Views: 2507
- Wed Feb 14, 2007 3:57 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: Hyperion; Destroyed Moon? (APOD 27 Jan 2007)
- Replies: 46
- Views: 15922
- Sun May 14, 2006 1:51 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: NGC 2440: Cocoon of a new white dwarf 5/7/06
- Replies: 19
- Views: 6695
Harry, instead of putting in only few lines of statements, why don't you give us an in-depth explanation of why your conjectures and hypotheses are correct? Please don't say you are working on it because if you know what you are talking about, you would have thought about your beliefs for a long tim...
- Thu May 11, 2006 3:35 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD 10 May 2006
- Replies: 6
- Views: 2859
It has been awhile since we saw the latest HST photo of Supernova 1987A in LMC. I wonder how far the blast wave has travelled by now. The last time I saw, it had lit up the inner ring.
http://hubblesite.org/newscenter/newsde ... 09/image/q
http://hubblesite.org/newscenter/newsde ... 09/image/q
- Wed Apr 26, 2006 4:40 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: No vacuum? (2006 April 26)
- Replies: 12
- Views: 3847
When we speak of vacuum in space, we are talking about relative to Earth's atmosphere, but you are correct that there is no such thing as pure vacuum up there. Space is filled with anything from sub-atomic matters to gas and dust molecules to meteorites to planets to stars. The comet's tail is creat...
- Mon Apr 24, 2006 7:05 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: NGC 253: Dusty Island Universe (2006 Apr 21)
- Replies: 2
- Views: 1740
Yes, galaxies do have a magnetic field, albeit a weak and disordered one compared to Earth's. Earth's magnetic field strength is about 5.0x10-5 Tesla. Our Galaxy's is about 5.0x10-10 Tesla, 100,000 times weaker. What you see in the picture is not, however, due to the galactic magnetic field. The exp...
- Sat Apr 22, 2006 12:36 am
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: Smoke from the Cigar Galaxy APOD 14/4/2006
- Replies: 18
- Views: 6341
Harry, It sounds like black holes are your favorite things! :D From your posts in several threads, you seem to think that black holes and their jets if they have any are the answer to almost everything! As Qev and others stated, the jets don't have enough matter and spread to trigger new star format...
- Fri Apr 21, 2006 4:48 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: Colliding galaxies
- Replies: 10
- Views: 3728
I'd say the probability of stars colliding during a collision of two galaxies is very low due to the vast distances between stars. For example, the distance between our sun and Alpha Centauri is 4.4 light years, or about 26,000,000,000,000 miles. Compared that with the sun's diameter of 880,000 mile...