Welcome to the r/SpaceX SES-9 Official Launch Discussion & Updates Thread [Take 2!]!

Let’s try this again!

After a 24-hour delay, liftoff of SpaceX's Falcon 9 v1.1 Full Thrust is currently scheduled for 23:47:00 UTC (6:47:00 PM EST) on February 25, the beginning of a 97-minute launch window. This mission will deliver the SES-9 communications satellite to a Geostationary Transfer Orbit for Luxembourg-based SES.

SpaceX will attempt to land the Falcon 9 first stage on their Autonomous Spaceport Drone Ship Of Course I Still Love You, but the odds of a successful recovery are low. In order to make up for launch delays, SpaceX has modified the flight profile to allow SES-9 to reach geostationary orbit as soon as possible. This means that the usual boostback burn won't be performed, and the ASDS will be located over 600 km downrange of Cape Canaveral.

You can read updates and comments from yesterday's launch attempt here.

Watching the launch live

To watch the launch live, pick your preferred streaming provider from the table below:

SpaceX Stats Live (Webcast + Live Updates)
SpaceX Webcast (Livestream)
SpaceX Full Webcast (YouTube)
SpaceX Technical Webcast (YouTube)

Official Live Updates

Time	Update
Paused	SES and SpaceX are now targeting to launch #SES9 on Sunday, 28 February, at 6.46pm ET, with a backup date on Monday, 29 February!
Paused	Sources say next Falcon 9 launch attempt is no earlier than Sunday at 6:47pm EST (2347 GMT)
Paused	Falcon 9/SES-9: Unofficial - SES now looking at a NET (No Earlier Than) March 3 launch option. Again, wait for SpaceX to make an official decision.
Paused	SpaceX: Countdown held for the day. Teams are reviewing the data and next available launch date.
Paused	No new launch date yet, but hopefully "within the next couple of days."
Paused	Problem appears to have been slow propellant loading.
Paused	No launch attempt today.
T-1m 15s	HOLD HOLD HOLD. The countdown has been aborted.
T-1m 26s	Strongback is fully retracted. 90 seconds to launch.
T-2m 11s	Stage two TVC (Thrust Vector Control) motion nominal.
T-2m 41s	FTS (Flight Termination System) is armed
T-2m 57s	Strongback lowering
T-4m 6s	The strongback arms are opening now.
T-5m 36s	Falcon 9 is transitioning to internal power now.
T-6m 14s	SpaceX still monitoring LOX (Liquid Oxygen) temps ahead of launch.
T-8m 54s	Engines have begun chilling
T-9m 18s	SES-9 is on internal power
T-10m 9s	The first stage's landing burn will use multiple engines!
T-11m 40s	The Falcon 9 first stage is now fully fueled.
T-16m 49s	Falcon 9's second stage is now fully fueled.
T-23m 36s	Launch is set for 6:47:00 pm
T-26m 40s	The SpaceX webcast is live!
T-30m 1s	Propellant loading underway. Launch targeting 6:47pm ET.
T-33m 1s	The launch team has given the GO to begin fueling!
T-37m 26s	At T-34 minutes the launch team will be polled. Fueling will begin at T-30 minutes if all is well.
T-1h 20m	SpaceX: One hour away from our live webcast at 6:25pm ET. Launch targeting 6:47pm ET
T-2h 16m	SpaceX: Weather for today's launch attempt at 80% go, though upper level winds and ground level winds remain watch items.
T-2h 22m	No major issues being worked as the countdown continues.
T-2h 33m	Everything is progressing smoothly towards an on-time launch. Radio checks and FTS (Flight Termination System) tests should be occurring shortly.
T-23h 7m	SpaceX has provided an official reason for the 24-hour delay: "Out of an abundance of caution, the team opted to hold launch for today to ensure liquid oxygen temperatures are as cold as possible in an effort to maximize performance of the vehicle."
T-23h 14m	The weather forecast (PDF) for the launch attempt on the 25th is looking much better. 80% probability of acceptable weather, with a >95% chance should the launch slip to Friday.

The Mission

The sole passenger on this flight is SES-9, a 5,271 kg communications satellite based on the Boeing 702HP satellite bus. SES-9 will use both chemical and electrical propulsion, the former to raise its orbit after separation from the Falcon 9 upper stage and the latter to circularize its orbit and perform station-keeping throughout its 15-year lifespan. The satellite will occupy the 108.2° East orbital slot, where it will be co-located with SES-7 and NSS-11, providing additional coverage to Asia and the Indian Ocean. Should everything go as planned, SES-9 will separate from the Falcon 9 upper stage just over thirty-one minutes after liftoff.

This will be the twenty-second Falcon 9 launch and the second of the v1.1 Full Thrust (or v1.2) configuration (the first being ORBCOMM-2 in December of 2015). This is SpaceX's second launch of 2016 (and their heavist GTO mission to date) as they begin to ramp up their flight rate, with an eventual goal of launching "every two or three weeks."

First Stage Landing Attempt

SpaceX will attempt a first stage landing on their Autonomous Spaceport Drone Ship named Of Course I Still Love You, which will be located approximately 660 km East of Cape Canaveral. Just over two-and-a-half minutes after liftoff, the first stage will shut down and separate from the upper stage. Because of the demanding flight profile, the first stage won't perform a boostback burn and will instead continue along a ballistic trajectory, reorienting itself for re-entry using cold-gas thrusters. After performing a reentry burn to slow down as it impacts the dense lower atmosphere, the stage will steer itself towards the drone ship using grid fins. If all goes as planned, the stage will perform a final landing burn and touchdown on the drone ship approximately ten minutes after liftoff.

This will be SpaceX's fourth drone ship landing attempt. Past attempts occurred during the CRS-5, CRS-6, and Jason-3 missions. Note that first stage recovery is a secondary objective and has no bearing on primary mission success.

Useful Resources, Data, ?, & FAQ

• Official SES-9 Press Kit, courtesy SpaceX
• SES-9 Multistream, courtesy u/kampar
• Hazard Location Map for SES-9, courtesy u/delta_alpha_november
• SES-9 trajectory simulation, courtesy u/TheVehicleDestroyer
• SpaceX Stats SES-9 Launch Countdown, courtesy u/EchoLogic
• List of useful Twitter accounts to follow, courtesy r/SpaceX
• Live auto-updating Reddit stream, courtesy Reddit Stream

Participate in the discussion!

• First of all, Launch Threads are a party threads! We understand everyone is excited, so we relax the rules in these venues. The most important thing is that everyone enjoy themselves :D
• All other threads are fair game. We will remove low effort comments elsewhere!
• Real-time chat on our official Internet Relay Chat (IRC) #spacex at irc.esper.net
• Please post small launch updates, discussions, and questions here, rather than as a separate post. Thanks!

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