MAVEN Launch Blog

Scientists think that Mars was enjoyed a thick atmosphere 4 billion years ago that was rich with the same chemical elements familiar to Earth’s own air. What happened since, though, is a mystery. The prevailing theory is that the Martian core of molten metal solidified and the magnetic field generated by the swirling core all but disappeared. Without a magnetic field protecting it from the sun’s solar winds, Mars lost its liquid water to either evaporation or freezing on the ground. Whatever happened, it left Mars a barren desert. MAVEN’s designers included instruments the spacecraft can use to detect the power of the solar wind at Mars along with the trace elements of the planet’s ancient atmosphere that still remain.

You can find out more details about the processes and theories in the MAVEN press kit available at: https://www.nasa.gov/sites/default/files/files/MAVEN_PressKit_Final.pdf

The Centaur upper stage performed its first burn and is now coasting with the MAVEN spacecraft aboard. It will coast until 2:09 p.m. EST and then reignite to put MAVEN on its final course for Mars.

The fuel and oxygen tanks on the Atlas V booster and Centaur upper stage are loaded with propellants now, a major step on the way to launching today at 1:28 p.m. EST. Launch controllers are getting ready for the last planned hold of the countdown, a 10-minute pause that begins at T-4 minutes.

The field mills around the launch site are back to green this afternoon following a switch to red conditions.

Launch controllers gave the “go” to begin loading liquid hydrogen, or LH2, into the Centaur upper stage. The Centaur will hold about 12,000 gallons of the propellant. The RL-10 engine burns hydrogen and oxygen to produce 22,300 pounds of thrust.

Today’s liftoff fire and thunder will be produced by an Atlas V rocket powered by an RD-180 engine at the bottom of the Atlas V first stage. The engine, which uses two thrust chambers and nozzles, burns rocket-grade kerosene and liquid oxygen to generate 860,200 pounds of thrust. A Centaur upper stage will take over four minutes, 18 seconds into flight after the first stage tanks are emptied.

The United Launch Alliance Atlas V booster made a name for itself quickly and will be called on again today to launch a NASA research mission. Atlas Vs launched the Curiosity rover that is operating on Martian soil now, along with the Juno spacecraft heading to Jupiter and the most recent Tracking and Data Relay Satellite (TDRS) for NASA, which is pictured.

 

The engine on the Centaur upper stage is being conditioned for the flow of liquid hydrogen through it later in the countdown. The stage will hold about 12,000 gallons of the minus-423 degree propellant. Meanwhile, controllers also are overseeing the loading of liquid oxygen into the Atlas V first stage.