OCO-2

The OCO-2 Spacecraft Is In Orbit...Now What?

In the pre-dawn hours of July 2nd we were anxiously awaiting the booster ignition of the Delta II rocket that would propel the OCO-2 (Orbiting Carbon Observatory) spacecraft into orbit. After a fairly quiet and uneventful countdown the engines ignited and filled the dark marine layer covering the launch pad with a bright orange glow. The launch rocket quickly climbed in altitude and within seconds was no longer visible from the ground level, only cameras positioned above the marine layer could still see the vehicle and the smoke trail it left in its wake. After what seemed like an eternity, the on-orbit coast between the 1st burn of the Delta II upper-stage and the very short 2nd burn the spacecraft was seperated from the launch vehicle and started entering into operation. Our job was now officially over, the spacecraft was delivered safetly to orbit. But what happens next?

Check-Out & Maneuver to Operational Orbit

The work of the launch team may be over, but the fun is just starting for the spacecraft team. There are all kinds of exciting activities going on in the spacecraft Mission Operations Center (MOC), including sub-system turn-on and check-out, system and instrument calibrations and manuver planning. Yes, I said maneuver planning. The spacecraft still must change it's orbit and get into the A-Train. The A-Train is short for "Afternoon Contellation". A Constellation is another name for a group of spacecraft flying relatively close to one another (see photo below of the A-Train Constellation).

The A-Train Constellation

The A-Train Constellation

It is called the "Afternoon Contellation" because this group of satellites operate in an orbit with an inclination near 90 degrees, which means they fly over the North and South poles of the Earth. As these spacecraft fly in their orbit and they cross the Earth's Equator going from South to North they cross the Equator when it is aproximately 1:30 pm local time at the point directly below the spacecraft on the Earth. As the spacecraft travels around it's orbit and comes 360 degrees aroung the Earth (which takes about an hour and a half) the Earth rotates under the spacecraft such that even though an hour and a half has passed the point directly below the spacecraft is still at 1:30 pm local time (but it is a different location on the Earth). OCO-2 crosses the Earth's equator twice per orbit, but it is the crossing that goes from South to North that the Constellation is named after. Each time it cross the Equator from South to North it is 1:30 pm in the afternoon directly below the spacecraft. This gives each of the spacecraft in the A-Train a consitant viewing condition in which to take scientific measurements. For more information about all of early orbit activities I recommend reading the OCO-2 blog called Blog By Randy, which is written by a member of the spacrcraft team on a daily basis. This is great way to keep up with everything the team is doing.

How To Follow The OCO-2 Mission

I'll write another post about the OCO-2 mission once it has reached it's final orbit in the A-Train and started it's science mission. In the mean time below are ways you can follow the OCO-2 mission:

  1. The NASA Earth Right Now Shareables flickr account has images from all of the NASA Earth Observing spacecraft including OCO-2.
  2. The JPL OCO-2 News site has news stories on OCO-2
  3. Follow OCO-2 on Twitter
  4. The NASA OCO-2 news site

And finally I leave you with my favorite OCO-2 launch photo.

My History with the Delta II Rocket

Tonight in just a few hours I will be on console to launch the NASA mission OCO-2 (Orbiting Carbon Observatory) on a Delta II launch vehicle. If you have noticed I haven't been posting as much content and as frequently as normal and that is because things get a little busy in the weeks and months leading up to a launch. As I am sitting in my hotel room relaxing before having a late dinner and going in for the launch, I am thinking back on my past missions I have worked that have flown on a Delta II launch vehicle:

EO-1 (Earth Observer-1):

EO-1 was my first assignment straight out of college. My role in this mission was the Lead Flight Dynamics Engineer at Goddard Spaceflight Center (GSFC) in the Flight Dynamics Facility (FDF). EO-1 is a technology demonstration mission, among other things. The main technology it was demonstrating was an autonomous maneuvering capability. This was the 1st time a NASA spacecraft had performed a maneuver (engine burn) on orbit without ground command interaction. The science for the mission was the "Observer" part of the name. EO-1 was following very closely behind a satellite called LandSat-7, which is also an Earth imaging spacecraft. My role in the mission was to design and execute the maneuvers on-orbit to fly EO-1 into the correct position behind Landsat-7 so they could take images of the same place on Earth at about the same time (which allows them to compare the data). So my job was all about calculating orbits. I even co-authored a paper about how the analysis we performed for the EO-1 formation flying that was required for the mission (you can read it here).

Mission Details:

Launch Vehicle: Delta II 7320 (the same configuration as for OCO-2)

Launch Date: Nov 21 2000

Launch Site: Vandenberg SLC-2 (same location we are launching from tonight)

Operational Status: Still operating under a mission extension

MAP (now called WMAP)

MAP (or WMAP as it is now called) stands for Wilkinson Microwave Anisotropy Probe. I started working on the mission design for WMAP before EO-1 even launched. My job with WMAP was to help design the maneuvers it had to perform after separating from the launch vehicle. The interesting thing about WMAP for me was that I got to see both sides of the mission. I was interviewing right around the time of the launch with the Launch Services Program. So I was in Florida and got to see the launch...my 1st launch viewing! I then got on a plane back to Maryland so I could get back to GSFC and help maneuver the spacecraft. The science WMAP was going after was to map the cosmic background radiation (low levels of energy left over from the Big Bang). For more information on the science results from WMAP go here.

Mission Details:

Launch Vehicle: Delta II 7425 (one more solid rocket motor than OCO-2 + an upper stage)

Launch Date: June 30 2001

Launch Site: Cape Canaveral Air Force Station (CCAFS)

Operational Status: Retired from service after 9 years, in a disposal orbit around the Sun

Mars Opportunity Rover (MER-B)

The Mars Opportunity-B (MER-B) mission was a launch training mission for me. I was backup on launch console and in training mode behind the primary NASA flight design engineer. This was my first Delta II launch experience since coming to work for the NASA Launch Services Program (LSP).

Mission Details:

Launch Vehicle: Delta II 7925H (6 more solid rocket motosr than OCO-2 + it was a heavy configuration)

Launch Date: July 7 2003

Launch Site: Cape Canaveral Air Force Station (CCAFS) Operational Status: Still operating on the surface of Mars

SWIFT

[SWIFT][sw] was a spacecraft with one main purpose, to quickly (or swiftly) detect, observe and alert Earth and other space based telescopes of the existence and location of a Gamma Ray burst (or GRB). By the time GRB's are detected on Earth we have missed much of the science concerning GRBs because they are very short lived events. SWIFT was my first mission to sit console on a Delta II mission for as the primary NASA engineer (launch vehicle flight design engineer). SWIFT is still detecting GRB's today and producing some really great science. In fact, each time SWIFT detects a new GRB it send a push notification to my phone. You can get the same alerts from SWIFT if you download the [SWIFT Explorer iOS app][app].

Mission Details:

Launch Vehicle: Delta II 7320 (the same configuration as for OCO-2)

Launch Date: Nov 20 2004

Launch Site: Cape Canaveral Air Force Station (CCAFS)

Operational Status: Still sending me push notifications to my iPhone about GRBs

As I look back I realize that even though I have launch missions on other vehicles besides Delta II, I really started my career with Delta II launched missions. OCO-2 is the 1st of the last 4 NASA missions to fly on a Delta II rocket, so I guess it is fitting that I get to be a part of one of the last few NASA launched Delta II missions considering how I started my career. My role in this particular Delta II launch is much different than the role I played in my previous Delta II missions. This is my 1st Delta II launch as an LSP Integration Engineer (or IE). My job tonight on console as a NASA IE is to make sure there are no issues with the spacecraft while it is preparing for launch on the launch pad. If there are issues with either the rocket or the spacecraft and the issue directly affects the spacecraft, I am the main NASA engineer that helps communicate and work those issues between the spacecraft team and the Delta II launch vehicle team. My call sign tonight on console is "NASA IE".

If you are actually awake and want to follow the launch online (launch is at 2:56 am pacific time), you can watch the following:

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