Whatever it was, it was surely terrestrial. I think it was probably a silvery mylar balloon. They last for weeks (at least in my house) before losing their bouyancy. A 7 arc second object would be about 1/5 of jupiter's diameter. Does this sound right? If it was a pancake shaped mylar baloon 2 feet in diameter it would have been about 11 miles away. Jupiter was about 60 degrees from the horizon at 8pm PST so that would put the balloon at an altitude of about 50,000 feet which seems high but I suppose possible. Maybe it was 14 arc seconds and only 25,000 feet altitude? The rate of travel would be it's own length times 5 over 2 seconds. For a 2 foot object that would be about 5 fps or 4 miles per hour. Assuming the object was traveling at a level altitude it would need to be faster - more like 6 mph which is a reasonable wind speed at that altitude. If the object was in our atmosphere it couldn't have been much more than 2 feet across - maybe 6 feet across at the most so that rules out airplanes. Birds travel much too fast - traveling a bird's own lengthX5 in 2 seconds is just too slow unless the bird was traveling in a 60 degree dive almost straight towards the observer (seems awfully steep) (wings might be too thin to see). A 4 inch high bird would have to be about 2 miles away but don't most birds look round when viewed straight on like this (excluding spread wings of course)? Satellites travel much much much faster than their length in 0.4 seconds. The only exception would be very close to geostationary orbit and then the satellite would have to be larger than any existing satellite. I think mylar balloon. Or some balloon between 1 inch and 3 feet across. - George Roberts ----- Original Message ----- From: "Brian Webb" <kd6nrp@earthlink.net> To: "See-Sat" <SeeSat-L@satobs.org> Sent: Tuesday, June 01, 2004 7:56 AM Subject: Unidentified Jupiter Transit > Hi All: > > Ernie Underhay of Oakview, California is seeking assistance in identifying > an object that he saw transit Jupiter last night. Here are the details: > > Date: 2004 June 2 > Time: 04:09 UTC (time is +/- about 2 minutes) > Latitude: 34.40000 (34 24' 00") N > Longitude: 119.29916 (119 17' 57") W > Elevation: 157 M (480 feet) > Equipment: 55mm flourite refractor, Wratten #8 filter, 65X maginification > > Underhay said he was observing Jupiter when he noticed an ill-defined > luminous or sunlit object against the dark sky near the planet. > > The object then crossed Jupiter's disk from south to north in about 2 > seconds. When the object was in front of the planet, it resembled a dark > cylinder or sliver about 6 to 7" long. The object's long axis was oriented > along the direction of travel. > > After it crossed the disk, the UNID was briefly visible and again resembled > an ill-defined luminous or sunlit object. > > Underhay has been involved in amateur astronomy for 40 years and has never > seen anything like this before. Perhaps someone in this newsgroup can > determine what he saw. > > Regards, > > Brian Webb > www.spacearchive.info > > ------------------------------------------------------------------------- > Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: > http://www.satobs.org/seesat/seesatindex.html > > ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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