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- Philip A. Stahl
Astrophysics/Expert Profile
Expertise
I specialize in stellar and solar astrophysics. Can answer any questions pertaining to these areas, the spectroscopic analysis of stars – as well as the magneto-hydrodynamics of sunspots and solar flares. Sorry – No homework problems done or research projects! I will provide hints on solutions.
Experience in the area
Have published papers on the relationship between sunspot morphology and solar flares; discovery of SID flares related to this, constructed computerized stellar models; MHD research.
Organizations
American Astronomical Society (Solar physics and Dynamical astronomy divisions), American Geophysical Union, American Mathematical Society, Intertel.
Publications
Solar Physics, Journal of the Royal Astronomical Society of Canada, Journal of the Barbados Astronomical Society, Meudon Solar Flare Proceedings (Meudon, France)
Education/Credentials
B.A. degree in Astronomy; M.Phil. degree in Physics - specializing in solar physics.
Awards and Honors
Postgraduate research award- Barbados government; Studentship Award in Solar Physics - American Astronomical Society
Average Ratings
Recent Reviews from Users
K = Knowledgeability C = Clarity of Response T = Timeliness P = Politeness| User | Date | K | C | T | P | Comments |
|---|---|---|---|---|---|---|
| Droo | 11/06/09 | 10 | 10 | 10 | 10 | Thanks - I knew it was right! |
| Droo | 11/05/09 | 10 | 10 | 10 | 10 | Thanks! I think I can solve this ..... |
| Alan | 11/04/09 | 10 | 8 | 10 | 10 | Dear Dr Stahl, Many thanks for the ..... |
| Sabrina | 11/02/09 | 10 | 10 | 10 | 10 | Thank you for your quick response; however ..... |
| Ana | 06/30/09 | 10 | 10 | 10 | 10 | Thanks :) my high school brain actually ..... |
Recent Answers from Philip A. Stahl
2009-11-05 Follow-up solution:
Congrats! You have it correct! The key to the solution was in seeing that, after you obtain the distance (d) to the system via the distance modulus, then you need to obtain the parallax angle applicable
2009-11-03 Binary star problem:
Hello, This looks like a fairly basic HW problem, so I will just get you oriented to solving it yourself. If you need more help after my hints, you can get back to me. First, if one of the stars
2009-11-03 Relative and Absolute Time:
Hello, Okay, you have really two separate issues and I don't want to get them confused - so will stick with just the question to do with the expansion of the universe. Basically, there are two theories
2009-10-31 astrophysics/ black hole theory:
Hello, There are several problems with your theory. Let's look at it from the aspect of stellar composition first. The fractional elemental abundances for a given star (of undetermined mass) can
2009-08-06 cmbr:
Hello, "CMBR" refers to the *cosmic microwave background radiation*. That is the 2.7 K temperature "relic radiation" left over from the big bang. ------------ Neeraj!? WHAT in blazes are you doing
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