Astronomy/asteriods

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Expert: - 4/23/2004


Question
Hi,
How can we measure the temperatures of two asteroids? and what can we deduce from the measurements?

Thanks,

-Rain

Answer
Rain,
Simply photograph the body in question using an infrared
telescope with infrared sensitive film, or equipment.
(Infrared is just a fancy word for heat).
The hotter the body, the brighter the object in the infrared, and thus the more heat radiation being emitted.

The bodies size (diameter) can be roughly deduced by either
assuming a very non-reflective surface similar to our moon,
which reflects only about 5 or 6% of the light and heat....
or a very reflective surface such as Venus.  Other studies
and visible light photographs may give the reflectivity...called albedo....and from that, an approximate diameter can
be deduced, knowing the distance and amount of incoming
sunlight received.

When Pluto was first discovered, it was thought by these
same studies, to be around 3000-3600 miles in diameter, because astronomers assumed a very dark surface...but when it was found that Pluto's surface was composed mainly of methane and ammonia frost...a lighter surface, the diameter was downgraded to only about half of that, 1500 miles in
diameter....so it turns out that Pluto is simply the largest
member of the Kuiper Asteroid belt out in that region....
and thus there are only 8 major planets in our Solar System.
(If Pluto were discovered today, it would not be called
a 'planet')...so I suspect that someday the astronomical
community will eventually wise-up, and downgrade Pluto
to large asteroid status.
Hope all this helps,
Clear Skies,
Tom Whiting
Erie, PA  

Astronomy

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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.

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