The Delta 2 rocket with Kepler has been cleared for blastoff Friday night at 10:49pm. There is a 90% chance of acceptable weather conditions predicted.

http://spaceflightnow.com/delta/d339/status.html

I haven't seen any posts on Kepler in a while and with the launch less than two weeks off I figured I might post :-)

The Kepler observatory made the 20 mile trip from the Astrotech cleanroom to LC-17B Thursday morning and after a couple days of delay due to weather was this morning lifted and mounted atop the 13-story Delta 2 rocket that will take it into space in 12 days. Some cleanroom shots from the media viewing a few weeks ago.

Launch is on target for Thursday March 5 at 10:48pm EST. There will be two launch windows of exactly three minutes each that day, stretching from 10:48:43 - 10:51:43pm and 11:16:34 - 11:19:34pm EST. NASA TV coverage begins at about 8pm or 8:30pm; www.nasa.gov/ntv.

I think it is officially NET May 7th now; it's now under review in the ELV status report and on the NASA schedule and being they only had the 24th and 25th before bumping to the May 7th window...

Windows (EDT):

May 07 - 19:29:07, 10 mins
May 08 - 20:14:55, 60
May 09 - 21:50:31, 60

The LRO photo category if you want to bookmark:

http://mediaarchive.ksc.nasa.gov/search.cfm?cat=201

The date of April 24 remains "official" for now but the ELV status report NASA issued yesterday says that while no formal request to delay to the May window (April 24, 25 and then no launch dates till May 7) has been made yet, discussions are in work as to whether April 24 is still a possibility. There is another Atlas 5 slated to go first, already delayed several times to March 9 and now looking at a delay of a few more days itself. They normally need close to 60 days turnaround time so I would be surprised if they keep April.

Being at the noon portion of the track comes into play in hybrid eclipses (2005 was the last one). In those cases the moon and sun are right on the border of being the same size in appearance, such that the eclipse can be total along the middle part of the track, but the Earth's curvature on the ends is enough to be farther away and it becomes an annular eclipse in those portions. There should be two points in those tracks where, if you went there, totality would last "zero seconds" or be instantaneous.

I'm not sure about Earth's rotation speed but I am sure it is one of yet more factors. There are probably better sources than me regarding this matter!

I think I can explain the main idea behind it...

The main factor is the distance between the Earth and moon, and the Earth and sun. If the eclipse occurs when the Earth and moon are closest and at the same time, the sun and Earth farthest apart during their orbits, the eclipse will last the longest as the moon is as large as it can be relative to the sun in that scenario. The maximum theoretical limit for a total solar eclipse is 7 min 31 sec.

By contrast, if the moon is at apogee and the Earth at perigee, the sun will be as far larger than the moon as it can be, creating the other extreme, a maximum duration annular eclipse.

Another factor in this situation is whether they slide passed each other exactly so that their radial centers cross, or if they slide passed each other slightly off axis. This can affect the time as well (just like a lunar eclipse, which is more easily seen... hitting the bullseye produces the longest).

On top of that, I believe your location on Earth an eclipse crosses can also have an effect.

The 2009 eclipse is the longest of the 21st century and will be 6 mins, 38.9 seconds long at the maximum point which is SE of Japan.

The other factor is that each eclipse varies in length along its track, with maximum duration in the middle. At the ends of the track, which occur where the Earth's surface is curving away from the shadow cone, the eclipse occurs at local sunrise or sunset and is shortest in duration because the shadow sweeps along the surface faster here (look at a spherical projection animation). The longest duration last week was 2 m 27 s, in northern Russia. Where I was, in southern Russia, it was 2 m 18 s. In China, less than 2 mins.

I hope this helps and that I didn't leave anything significant out.

In the meantime I have posted more photos and sequences:
http://www.launchphotography.com/Total_Sol...lipse_2008.html

I traveled to Siberia for the eclipse. I have uploaded a few photos, and will post more soon:

http://www.launchphotography.com/Total_Sol...lipse_2008.html

It was spectacular!

I believe 60 days after launch.

If anyone is still paying attention, live coverage begins on NASA TV's media channel (only) at 9:45am EDT. There is a 40% chance of weather violation. Today they would have been no go for sure, it was stormy from around 10am through the day.

June 11 now.

It appears that this involves a battery with respect to the flight termination system (FTS) and that the GLAST vehicle will get its battery from Jason; Jason will get a new one. I don't know what that means for the dates.

We're looking at an indefinite postponment now. The range is refusing to allow a waiver on a rocket issue, for both GLAST and Jason.

Launch postponed to June 8 now :-P

The difference between a 32,000 lbs module or even having an empty payload bay has little effect on 7.5 million lbs of thrust.

This was not even the heaviest ISS piece taken up by the shuttle, remember.

There is a 70 percent chance of acceptable weather both the 7th and 8th.

Now June 7 and counting :-P I'm not sure what the issues are exactly.

June 6 now, earliest.

Launch is now June 5, same time.

Well, thanks. :-)

The June 3 launch day will only occur if the shuttle goes May 31. If the shuttle is scrubbed 24, 48 hours then GLAST will delay accordingly with three days between them. If the shuttle were to be delayed much beyond it, GLAST would surely go first.

Well, the first night launch after Columbia was STS-116 on Dec. 9 2006. And it was a beauty. 123 was the second.

The Return to Flight 114 landed at night early in the morning; 115 also landed early in the morning at about 6am.

The times are dictated by the orbit of the ISS (or Hubble). It so happens that landing from station flights tends to wind up being 4-6 or so hours before the launch time most of the time (and most of the time has been on the ascending node heading north over the equator). STS-120 in October was an exception, as they came in on the descending node. 11am launch, 1pm landing. Looking at the others though, 114 was 10am launch and 5am landing; 121 3pm and 9am; 115 11am and 6am; 116 9pm and 5pm; 117 7pm and 1pm; 118 6pm and noon; 122 245pm and 9am, etc.

The day launch rule went into effect after Columbia for a while but as they got around to resuming flights they decided that after two foam-loss-free flights they would allow them again. Well you may recall that 114 shed foam; so, two more had to happen. But on the third post-Columbia mission, 115, they decided to lift it when 115 was facing a hurricane delay and would have had to wait a month for another day opportunity.

STS-115 was the last night landing in Sept 06; STS-114 the Return to Flight also landed at night.

Although it was normal, most longtime observers are saying they haven't seen it this pronounced in a long time. One said that STS-51 was about the same.

Very beautiful launch, best ELV of the year. Here are some of the photos I took:

http://www.launchphotography.com/Dawn.html

The media were relocated (somewhat by choice) to Jetty Park, but that turned out to be a beautiful turn of events. That's my favorite viewing site and it's rare that I can really go there.

Nice meeting you Ken! Enjoying the blogs too.

Second stage fueling has been completed.

Launch weather outlook is favorable with a 30% chance of violation.

Launch has been postponed to Thursday, Sept. 27 at 7:20am. Weather has prevented fuel loading on the second stage again (already a day late this week).

128/130. Yes, it is a new modern record streak.