AboutTom 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!
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
I also attend several regional starparties during the year, and have been on 5
total solar eclipse expeditions.
Organizations: President, Erie County Mobile Observers Group
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.
Expert: Tom Whiting Date: 7/24/2008 Subject: Planet or Star?
Question Hi Tom,
I live near Clark and Addision in Chicago Illinois, ZIP 60657. Lately, I've noticed an extremely bright star (it's prominence is second only to the moon) which I would guess is a planet, S SE of my home for weeks now. Is there some planet currently in view for us at this time? What is this extraordinarily bright light?
Thank you so much!
Answer Hi Sean,
Yes, you are correct, it's the planet Jupiter at -2 magnitude, just past opposition now (as we just passed it up, as we do every 13 months) so since Venus is currently behind the sun, Jupiter is the brightest pinpoint of light in our night sky now. But later this fall, Venus will slowly climb into the western sky and set about two hours after the sun, and will reclaim the brightest pinpoint object, at -4th magnitude. Just put binoculars on Jupiter, and you can see it's 4 brightest Galilean moons on each side of it. That's all you need, because those moons would be naked eye were it not for the overpowering glare of the planet itself.
And yes, -4 is brighter than -2 because the magnitude system of brightness is a reverse scale, the lower the number, the brighter the object. And it's notlinear, it's exponential; Each difference is 2.5 times brightness change. And so it does not go 2.5, 5, 7.5, 10 times brightness, BUT rather 2.5, 2.5 squared, 2.5 cubed, and so on.
So the difference in brightness goes 2.5, 6.25, ~16, 40, 100.
A 5 magnitude change is a 100 times change in brightness.
(I didn't invent it, I just report on it).
So Venus will be 6.25 times brighter than Jupiter, once we canobserve it in the western sky after sunset, this coming Autumn.
Oh, and Jupiter is now low in the southern sky because it' in EasternSagittarius, about the lowest it can get (where the sun is locatedin January). Since Jupiter takes 12 years to orbit the sun, it spendsabout one year in each Zodiac constellation, so next year you findit about 30 degrees east of it's current location, so it will bea little higher in Capricornus, just east, right next door to, Sagittarius.
Hope this helps,
Clear Skies,
Tom Whiting
Erie, PA
FOLLOW UP:
Sorry, I don't know why my computer is suddenly putting a question
mark after a period...just disregard all the question marks in
previous answer.
