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Since it has been relatively slow in the space world as of late notwithstanding the ECLSS issues on the ISS, I figured that a US rocket launch would be of some interest.

This will be the first launch of the Atlas V rocket in the 531 configuration. That means that the rocket will fly with a 5-meter diameter payload fairing and three strap-on solid rocket boosters. The Atlas V has flown twice with three SRBs before, in the 431 configuration with a 4-meter diameter fairing. The payload for this flight will be the first AEHF satellite for the US Air Force. Launch from SLC-41 at Cape Canaveral is planned for 11:07 UTC (7:07 EDT) on 14 August, and has a two hour launch window.

AEHF (Advanced Extremely High Frequency) is the successor/replacement to the Milstar communication satellites which were launched by the Titan IV between 1994 and 2003.

ULA press release wrote:The AEHF constellation of satellites will provide 10 times greater capacity and channel data rates six times higher than that of the existing Milstar II communications satellites.

There will be three AEHF satellites which will replace the entire Milstar constellation.

The rocket was rolled to the launch pad this morning:

Photo credit: Pat Corkery, United Launch Alliance

The launch will be webcasted by the United Launch Alliance on their website:
http://www.ulalaunch.com

There is also a mirror available if you cannot get the webcast to work (which begins 30 minutes before the planned opening of the launch window):
http://mfile.akamai.com/29730/live/reflector:58048.asx?bkup=58227

Note: Wikipedia links embedded into the text for relevant articles.

Well, the launch went ahead as planned at 11:07 UTC on 14 August and now AEHF-1 is in a super-synchronous transfer orbit pending its own apogee motor firing to raise the spacecraft to its final geostationary location.

I have not been able to find a launch video, so the official launch image from ULA will have to do:

Photo credit: Pat Corkery, United Launch Alliance

And for more on the launch as well as the satellite and the system it will be a part of, here is an article I recommend:
http://www.nasaspaceflight.com/2010/08/ula-atlas-v-launch-with-aehf-gps-satellte/

da man wrote:super-synchronous transfer orbit pending its own apogee motor firing to raise the spacecraft to its final geostationary location.

Can you explain that to me as if I were a 6 year old... ?

AndesSMF wrote:

da man wrote:super-synchronous transfer orbit pending its own apogee motor firing to raise the spacecraft to its final geostationary location.

Can you explain that to me as if I were a 6 year old... ?

Although it is possible to directly inject a satellite into its final geostationary location, that option means that more mass is required via fuel for the launcher which can reduce the operational life of the satellite due to the amount of mass allowed for its own propellant tanks to be filled. Therefore the more common solution is to go to an intermediate point determined by orbital mechanics and then a small motor on the satellite itself will fire to place the satellite into its final orbit,thus allowing for a longer life for the satellite. The type of transfer orbit, in this case is a newer-type which brings the satellite closer to its final location than a standard GTO due to excess performance from the launcher (something that happens with most EELV launches).

For more: http://en.wikipedia.org/wiki/Geosynchronous_transfer_orbit

I can give an example of a GTO+ (super-synchronous transfer orbit) and a standard GTO using the same launcher as this launch (Atlas V only in the 421 configuration):
On 14 August 2008 the ICO G1 commercial communications satellite was launched into a 187 km x 35925 km x 22.7 deg GTO
On 4 April 2009, the WGS-2 military communications satellite was launched into a 408km x 66811 km x 20.93 deg GTO+

What was the length of that vehicle, it looks taller than the earlier Atlas V's with the 4m fairing.

Queso wrote:What was the length of that vehicle, it looks taller than the earlier Atlas V's with the 4m fairing.

Same as the 400 series, the reason it looks different is because the fairing encloses the Centaur second stage on the 500 series whereas the Centaur is un-shrouded on the 400 series.