Astronomy/The ecliptic plane

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Expert: - 9/14/2009


Question
Dear Tom,

I am new to astronomy and would like to know if the ecliptic plane is right above my head in the night sky i.e. if I tilt my head right back will I be looking at the ecliptic plane

Answer
Hi Kieran,
Only those observers that live on the equator and 23.5 degrees north or south of the equator
have the ecliptic plane directly overhead at their zenith.

The ecliptic plane is defined as the center of sun and center of the Earth. It defines the
plane of the solar system, so wherever you see the sun, and all the bright planets
(and even the moon)...that's the ecliptic plane. For Australia, face north, and most of the
time the ecliptic plane is roughly 45-55 degrees elevation, or roughly about halfway up from the
northern horizon to your zenith, unless you live in very northern Australia, then it's up
a little higher in your sky.  In your winter months of June and July, the plane is lower in
your daylight hours (where the sun is), and much higher at night, and it's the reverse in your summer months of December and January, because it varies by 23.5 degrees doubled, or 46 degrees of sky.  

The moon will vary as much as 5 degrees above or below the ecliptic plane during it's 29 day travel around the Earth, but it gives you a close idea where that plane is located in your night sky. Notice at times that the moon just misses the bright planets of Jupiter, Saturn, and Venus, which vary only a couple degrees from the true plane.
Hope this helps,
Clear Skies,
Tom Whiting
Erie, PA USA

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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