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Can Jupiter Cast a Shadow...on Earth?

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#1 StarStuff1

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Posted 14 August 2010 - 05:07 PM

Last Friday morning I was watching the Perseid meteor shower from a dark site at about 3000 ft. It was very clear overhead and Jupiter was near the meridian, blazing away very brightly. It was just after 4 am.

In the past I have seen Venus cast a shadow of my hand on the ground. I had never read where this could be done by Jupiter so I tried it out. I held one hand 6 or 8 inches over the other. By golly I saw a very faint shadow. This was repeated a couple of more times and there was definitely a shadow. The bright Milky Way was much farther to the west so I don't think that was the source of the shadow. Jupiter is in Pisces and there aren't too many bright stars nearby.

Is this possible or am I :lalalala:

Terry

#2 azure1961p

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Posted 14 August 2010 - 07:46 PM

Could be general sky glow, star as a whole included?

At anyrate, in theory it does cast a shadow, the catch is to have something sensitive enough to record it. Can the eyes do it? Did yours?

Good question.

A real tough one is pointing your tele at a G2 star and seeing if you can tan your eyelid ;)

Pete

#3 StarStuff1

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Posted 14 August 2010 - 10:05 PM

Well, I purposely "aimed" my hands towards Jupiter to ward off MW glow. Perhaps total sky glow. I dunnow. I am a 30 year vet of amateur astronomy and have been teaching astro labs at the local U for almost 10 years so not a newbie. But then again I am not a scientist, either. Like I said, the shadow was not real obvious but it was there.

A GOOGLE search before my original post here did not reveal any answers.

#4 Dave Mitsky

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Posted 14 August 2010 - 10:20 PM

I've seen both Jupiter and Mars (in 2003) cast shadows from dark sites.

http://adsabs.harvar...PA.....14..123D

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#5 StarStuff1

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Posted 15 August 2010 - 01:20 PM

The info in that link and your observations confirm it. Thanks, Dave.

Maybe others will look for shadows caused by Juiter during the next no Moon phase when Jupiter is even closer to opposition.

#6 azure1961p

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Posted 15 August 2010 - 09:20 PM

I've seen both Jupiter and Mars (in 2003) cast shadows from dark sites.

http://adsabs.harvar...PA.....14..123D

Dave Mitsky


Nice link Dave. Ill bet it can be imaged with a timed exposure in that case.

Pete






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