Search found 631 matches
- Mon Mar 28, 2011 5:12 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27)
- Replies: 64
- Views: 8438
Re: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27
I see two large impact basins in the MOLA map. Which on is the Hellas Impact basin? Lava flow will create a plateau, but will not swell the crust and then cause a portion to collapse in various places creating huge valleys. The falling debris could have created some the elevated terrain in the north...
- Mon Mar 28, 2011 4:04 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27)
- Replies: 64
- Views: 8438
Re: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27
My survey of the forum has revealed very little support for an impactor on Mars causing the Valles Marineris except for Von Daniken; however, Mars is the site of some of the largest impact basins in the solar system and also has the largest mountain volcano. The Wikepedia reason for this largest of ...
- Sun Mar 27, 2011 10:21 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27)
- Replies: 64
- Views: 8438
Re: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27
The nonprophet's hypothesis also states that the collisional material accretes to become the Earth's moon. Martian gravity field and the necessary momentum and energy changes work against any substantial material moving toward the Earth's orbit. Any transfer of water should either be totally dispern...
- Sun Mar 27, 2011 8:44 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27)
- Replies: 64
- Views: 8438
Re: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27
Ron, I am only asking for your opinion and use any kind of logic you wish.
3/27/2011
3/27/2011
- Sun Mar 27, 2011 8:40 pm
- Forum: The Library: Information Desk and Educational Resources
- Topic: Acceleration of cosmic rays by supernova
- Replies: 3
- Views: 738
Acceleration of cosmic rays by supernova
The Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics, PAMELA, has been measuring cosmic rays for the past three years. The origin of cosmic rays from supernova is now being disputed. Cosmic rays are actually fast-moving particles that carryan extraordinary amount of energy and...
- Sun Mar 27, 2011 8:23 pm
- Forum: The Bridge: Discuss an Astronomy Picture of the Day
- Topic: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27)
- Replies: 64
- Views: 8438
Re: APOD: Valles Marineris: The Grand Canyon... (2011 Mar 27
What caused this so-called 3000 km crack ? The explanation of the APOD claims this is a crack due to crustal shrinkage; I would think there should be other cracks as well. Another claim is that a huge asteroid side-swiped Mars and then went on its merry way. A "side-swipe" this large is to...
- Sun Mar 27, 2011 7:45 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
Re: NOT Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
I now have a vision of globular clusters being formed. Thanks to you and Jabberwren, I have read Owlice's references and articles about metallicity and reionization. After the Big Bang and the inflationary period baryons were created because considerable cooling occurred causing electrons and proton...
- Sat Mar 26, 2011 8:35 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
Re: NOT Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
Ann, thanks for providing a very convincing timeline or history for the observable galaxies. I did not think there would be any ideas of a galaxial history in my lifetime. What remains is one of the bigger mysteries of galaxies. How did globular clusters, some the oldest structures in the universe, ...
- Fri Mar 25, 2011 3:31 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
Re: NOT Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
My guess is that you are right about that, Doug. I've been thinking more about what you said about the bubble-like dust structures in NGC 2841. I found this old Hubble image of NGC 2841, where bubble-like dust structures are quite obvious: http://en.wikipedia.org/wiki/File:NGC_2841_Hubble_WikiSky.j...
- Thu Mar 24, 2011 9:12 pm
- Forum: Starship Asterisk: Handbook
- Topic: Help on using BBCode
- Replies: 35
- Views: 670122
Re: Help on using BBCode
I thought there should be a better way. thanks. Doug
- Thu Mar 24, 2011 9:10 pm
- Forum: The Library: Information Desk and Educational Resources
- Topic: Strong magnetic fields aided formation of solar system
- Replies: 5
- Views: 782
Re: Strong magnetic fields aided formation of solar system
Rob,
I have not thought of non-thermal ionization. But don't electrons from beta decay easily and quickly find another atom with an room in the outer electron shell ? I will check out the book if it is not too cramed with mathematics.
3/24/2011
I have not thought of non-thermal ionization. But don't electrons from beta decay easily and quickly find another atom with an room in the outer electron shell ? I will check out the book if it is not too cramed with mathematics.
3/24/2011
- Thu Mar 24, 2011 8:50 pm
- Forum: Starship Asterisk: Handbook
- Topic: Help on using BBCode
- Replies: 35
- Views: 670122
Re: Using Quotes
I prefer your quoting system, but do not know how to perform this function. There are two different "quote buttons" on the screen. When I activate the top quote button it just highlights everything inside its related box and indicates the existing quote signs. I came from the other genera...
- Thu Mar 24, 2011 8:26 pm
- Forum: The Library: Information Desk and Educational Resources
- Topic: Strong magnetic fields aided formation of solar system
- Replies: 5
- Views: 782
Re: Strong magnetic fields aided formation of solar system
A cold molecular cloud of dust and gases starts to collapse due to some higher concentrated density gradient. How is the plasma and magnetic field generated? Certainly a magnetic field can be generated if ions and electrons in a plasma are in motion, but what energy caused the plasma which needs ve...
- Thu Mar 24, 2011 7:51 pm
- Forum: The Library: Information Desk and Educational Resources
- Topic: why are spins and orbits the same direction?
- Replies: 10
- Views: 1154
Re: why are spins and orbits the same direction?
Its true that most of the angular momentum in the solar system is in the planets (mostly Jupiter). Its also true that magnetic fields and plasma effects are a dominant driver of angular momentum transport and other dynamics in most accretion disks. Its implausible that the magnetic fields played th...
- Thu Mar 24, 2011 6:42 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
Re: NOT Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
What seems to be supported by mathematics and theory per Wikipedia is that X-rays from the core of a typical galaxy and various overlays of explosions from supernovae produce high frequency X-rays that can breakdown dust in a typical giant IMC in 40 to 50 millions years if it has not already establi...
- Thu Mar 24, 2011 2:32 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
Re: NOT Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
Ann, thanks again for your very detailed replies. My question is still lingering. What really are the dust structures that pervade NGC 2841 ? Also, how do X-ray emisions from a galaxy core destroy the dust formed in the galaxy within 46 million years ? What is the physical mechanism at work ? Let's ...
- Wed Mar 23, 2011 7:37 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
NOT Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
Hello Ann, You are correct. We are thinking about different structures in the galaxy when we are referring to "plumes". My questions about plumes are in regards to structures situated well inside the the central regions of the disk that look like bubbles. I am not referring to the "pl...
- Mon Mar 21, 2011 3:16 pm
- Forum: The Library: Information Desk and Educational Resources
- Topic: Strong magnetic fields aided formation of solar system
- Replies: 5
- Views: 782
Re: Strong magnetic fields aided formation of solar system
Hello Chris, I have missed your companionship. I have been away for about two weeks. I do agree with all that you stated. This issue is about how the planets obtain the same angular momentum vector for both their orbits and spins. And, I agree with you that there is no reason to have high enough tem...
- Mon Mar 21, 2011 2:58 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
Re: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
Hello Ann, I want to confirm that we are thinking the same way about the aforementioned "plumes". Plumes are the aftermath of supernovae and novae. From our vantage point we are looking at the outside envelop of supernova and red giant remnants. These envelops, or bubbles, or plumes still ...
- Sun Mar 20, 2011 10:07 pm
- Forum: The Library: Information Desk and Educational Resources
- Topic: Strong magnetic fields aided formation of solar system
- Replies: 5
- Views: 782
Strong magnetic fields aided formation of solar system
Neufer made a very interesting statement during our discussion of why spins and orbits are in the same direction. Allow me to quote Art: "When the solar system was formed it was probably a plasma locked into a constant rotation rate by strong magnetic fields. You cannot ignore the plasma/magnet...
- Sat Mar 19, 2011 11:32 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
Re: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
Ann, thank you for your very descriptive explanation of the colors and mixture of colors and over-powering brightnesses found in various parts of galaxies. So summarizing, the comparative oldest age of part of a galaxy reveals its overall age, although it is hard to nail-down the precise number of ...
- Tue Feb 22, 2011 11:22 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
Re: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
Ann, thank you for your very descriptive explanation of the colors and mixture of colors and over-powering brightnesses found in various parts of galaxies. So summarizing, the comparative oldest age of part of a galaxy reveals its overall age, although it is hard to nail-down the precise number of b...
- Tue Feb 22, 2011 6:46 pm
- Forum: The Library: Information Desk and Educational Resources
- Topic: What favors orbit or collision of two planetoids ?
- Replies: 23
- Views: 1391
Re: What favors orbit or collision of two planetoids ?
I remember buying my first snow skis. They were bait for extremely warm winter for about two years. Well, I am pleased to know that other stars have Kuiper Belts. It confirms my personal opinion that the outskirts of stars systems with outer planets, which I believe to be the typical case, are "...
- Tue Feb 22, 2011 6:28 pm
- Forum: The Asterisk Café: Discuss Anything Astronomy Related
- Topic: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
- Replies: 69
- Views: 8923
Re: APOD: Spiral Galaxy NGC 2841 Close Up (2011 Feb 19)
Thank you for the correction. I really meant the influences of a rapidly moving gravity field (in cosmic time) and fluid dynamics.
Doug 02/22
Doug 02/22
- Tue Feb 22, 2011 6:09 pm
- Forum: The Library: Information Desk and Educational Resources
- Topic: What favors orbit or collision of two planetoids ?
- Replies: 23
- Views: 1391
Re: What favors orbit or collision of two planetoids ?
How do these detected belts compare in density to the our Kuiper Belt and how far away can they be detected ?
Chris, what is a cloud angler ? I know you have an observatory but do not understand the connection. Perhaps when you visit your observatory you may take side trips to go fishing ?
Doug
Chris, what is a cloud angler ? I know you have an observatory but do not understand the connection. Perhaps when you visit your observatory you may take side trips to go fishing ?
Doug