On Friday, NASA managers cleared the shuttle Atlantis and its crew for blastoff Dec. 6 to the International Space Station (STS-122). Atlantis is scheduled to lift off from pad 39A at the Kennedy Space Center at 4:31:44 p.m. EST next Thursday, roughly the moment when Earth's rotation carries the launch pad into the plane of the orbit of the ISS. As I noted a few weeks ago, the stage is now set for a most interesting scenario for observers in the NYC Area because the time of liftoff comes just five minutes after local sunset. There is a precedent dating back more than 16-years ago: Back on September 12, 1991, STS-48 was launched at 7:11 p.m. That was only one-minute after local sunset for NYC. And yet, I still consider that as the best Shuttle launch I've ever seen from the NY area because the Shuttle orbiter and its orange external fuel tank were illuminated by sunlight as it moved parallel to the US East Coast. This made the Shuttle appear incredibly bright . . . from Levittown, Long Island (where I was living back then) I estimated the total magnitude of the "stack" (orbiter & external tank) at -5 -- brighter than the planet Venus! Moreover . . . instead of flickering out into invisibility at MECO (main engine cutoff ~ 8.4 minutes after liftoff), what was observed was a "puff" of vapor emanating from the Shuttle. Thereafter, the orbiter continued to be visible as it rapidly sailed off toward the northeast. Moreover, through 7 x 35 binoculars, I could actually see the separation of the whitish orbiter from the dull orange external tank, which occurs at an altitude of about 73-miles about 400 miles southeast of NYC. This was indeed a rare and spectacular sight. I have been waiting all these years since for another shuttle launch that similarly would coincide with a time just after local sunset and it now appears that next Thursday (weather conditions permitting, of course) another opportunity will finally come my way. Interestingly, at Cape Canaveral, the launch occurs 54-minutes before local sunset in a bright daytime sky. But as Atlantis gradually plods northeastward, paralleling the southeast and middle Atlantic coastline, it will move toward the Earth's terminator line, separating daylight from darkness. From the NYC area, the Shuttle will probably first become visible very low above the southern horizon about 7 to 8 minutes after liftoff (4:38 to 4:39 p.m. EST). It then will move rapidly over to the south-southeast, where at MECO (4:40.1 p.m.) it will reach a maximum altitude of 8.5-degrees above the horizon. It will then race to the east-southeast where both orbiter and the external tank should disappear about a minute or so later. This display will also be visible from southern New England and might even be observable from locations to the south of NYC, even from where the Sun will still be just above the southwestern horizon (such as Ocean City, Maryland). -- joe rao **************************************Check out AOL's list of 2007's hottest products. (http://money.aol.com/special/hot-products-2007?NCID=aoltop00030000000001) ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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