Update - December 21, 2015, 10:45 a.m. PST:
Today's Falcon 9 / Orbcomm-2 launch time has been changed to four minutes earlier than reported yesterday. This is important as the launch window is only open for about one minute.
Updated launch times for TODAY:
8:29 p.m. EST
5:29 p.m. PST
0229 Central Euro Time, Tues Dec 22.
Live coverage will start at http://www.spacex.com/webcast/ about half an hour prior to launch time.
Update - December 20, 2015, 4:30 p.m. PST:
Weather is 80% favorable for tomorrow's launch time. The launch window is open for just one minute.
If there is a landing attempt tomorrow, it will occur about 10 minutes after lift-off at SpaceX's Landing Zone 1, formerly known as Launch Complex 13. This location is near the eastern tip of Cape Canaveral.
If you are on the ground near the landing site, you will hear a sonic boom as the rocket returns to Earth. From nearby locations, you may also see the rocket's engines firing in the dark in preparation for landing.
News media won't be allowed to cover the launch and landing, so I'm counting on landing updates from spacetweeps who will be at the space coast tomorrow.
Update - December 20, 2015, 1 p.m. PST:
Elon Musk just tweeted that launch will be delayed by 24 hours to December 21, 2015. Tomorrow's launch time is 8:33 p.m. EST (5:33 p.m. PST). That is 0233 Central European Time on Tuesday, December 22.
Just reviewed mission params w SpaceX team. Monte Carlo runs show tmrw night has a 10% higher chance of a good landing. Punting 24 hrs.— Elon Musk (@elonmusk) December 20, 2015
He also RT'd this image of Falcon 9 on the launch pad at Cape Canaveral at sunset today:
New photo of @SpaceX #Falcon9 in advance of tonight's ORBCOMM #OG2 launch. She's a beauty. #SpaceX pic.twitter.com/cUhCgGieiP— ORBCOMM (@ORBCOMM_Inc) December 20, 2015
Update - December 20, 2015, 11 a.m. PST:
Everything still looks good for a launch attempt today at 5:29 p.m. PST. SpaceX's coverage will start at 5:05 p.m. PST at spacex.com/webcast. The site is already displaying a countdown clock, which is a good sign. I'm not sure if NASA TV will live stream the launch. The launch window is 1 minute long and there are no other windows available today, should the launch not occur at 5:29 p.m.
For those of you at Cape Canveral: Keep looking up after the launch. SpaceX may attempt to land the redesigned Falcon 9's upper stage on land near the launch site.
I hope so. It would be fitting for Falcon 9 to return to actual, real-life flight the same weekend a movie soars to box office dominance that features the fictional ship - the Millennium Falcon - after which Falcon 9 was named.
Falcon 9 has been grounded since June, due to a failed launch attempt that was intended to deliver a Dragon cargo capsule to the International Space Station as part of NASA's commercial crew program. Tomorrow's flight will carry 11 second-generation Orbcomm satellites to orbit and will mark the second time SpaceX will deliver New Jersey-based Orbcomm's satellites into space.
The launch has been delayed since August and several times during December. The past week has seen problems with pre-flight static firing tests. The test was completed successfully last night and tomorrow's launch is contingent upon a review of the static fire data.
Elon Musk said on Twitter that all looks good for a Sunday launch from Cape Canaveral:
Currently looking good for a Sunday night (~8pm local) attempted orbital launch and rocket landing at Cape Canaveral— Elon Musk (@elonmusk) December 19, 2015
Image credit: SpaceX
The exact launch time is Sunday, December 20 at 8:29 p.m. EST (5:29 p.m. PST).
Falcon 9 has received some upgrades: more powerful Merlin 1D engines arranged in their trademark "octaweb" configuration - eight Merlins arranged around one in the center. Together, the engines can generate 1.5 million pounds of thrust. The older generation Merlins generated a maximum of 1.3 million pounds.
The redesigned Falcon is also a little taller, 229 feet (69.9 m) instead of 224 feet (68.3 m), to accommodate longer nozzles and extended tanks on the upper stage engines.
In addition, the improved Falcon 9 will use super-cooled, compressed fuel, which allows the rocket to carry more fuel that can be used in a landing attempt.
Jeff Bezos's company Blue Origin successfully launched a rocket to space and then landed it on a pad in West Texas just last month, and made rocket science history in the process.
SpaceX is also developing re-usability technology. A landing attempt may occur tomorrow on land near Cape Canaveral. At the moment, I can find no information on the likelihood of a landing attempt or the likely landing location near KSC. If you're on the space coast tomorrow, you just may find yourself in the right place at the right time to see a rocket stage *land* at Cape Canaveral for the first time ever.
I will update this post if new information comes in. I will also live tweet the launch tomorrow, starting around 5 p.m. PDT. The launch window is very brief, with no others available tomorrow.
Go Falcon 9!!