Astronomy/astronomy

Advertisement


Question
what is the parallax angle of a star that is 32.6 Ly distant?

Answer
Hi Gina,
A star at one parsec ( = 3.26 ly) would have a parallax angle of 1 arcsec.
(The simple formula is distance in parsecs = 1/parallax angle in arc-seconds.)
So a star at 32.6 ly (which is 10 parsecs distant) or 10 times more distant,  would have a parallax angle of 0.1 arcsec.  Fitting 0.1 arcsec into the above formula, d = 1/0.1 = 10 parsecs.  Q.E.D.
Clear Skies,
Tom Whiting
Erie, PA USA

Astronomy

All Answers


Answers by Expert:


Ask Experts

Volunteer


Tom Whiting

Expertise

Astronomy has been my hobby/pasttime for over 50 years.  Currently own 3 telescopes, the largest of which is a 30 inch Newtonian truss Dob that is portable.I taught Astronomy/Meteorology at the University Level for 13 years before retiring in 1995. Being retired and home most of the time, I am able to answer all questions relatively quickly, unless it's a new moon weekend with good observing conditions.  No astrology questions please, or questions about alleged UFO picture identifications.

Experience

Experience: Astronomy has been my hobby and study for over 50 years. We currently now own a 30 inch portable telescope (Updated - Pennsylvania`s largest portable telescope). It can be seen on our website at:http://www.velocity.net/~bwhiting and also attend several regional starparties during the year, and have been on 5 total solar eclipse expeditions.

Organizations: President, Erie County Mobile Observers Group for over 15 years.

Publications: Wrote the "Over Erie Skies" newspaper article in our local newspaper for 11 years (1975-86).

Education: Masters Degree- Taught at the University level for 13 years. Retired 20 years -USAF Pilot - KC-135 with 180 combat missions;  Also Eagle Scout, Philmont staff 2 Yrs, Order of Arrow Lodge Chief, Ham Radio (inactive).

Awards: two discoveries: The mini-coathanger asterism in Ursa Minor (the little dipper) And the mini-ladle- another asterism in the bowl of Ursa Minor. Clients: Currently President of the ECMOG as mentioned above.

Education/Credentials
BS  Metallurgical Engineering Grove City College, PAMaster's Degree, Gannon University, Erie, PA Also retired USAF pilot, 20 years.

©2012 About.com, a part of The New York Times Company. All rights reserved.