Ground crews at Vandenberg Air Force Base
in California raised a United Launch Alliance
Atlas 5 rocket on its launch pad earlier this
month in preparation for liftoff May 5 with
NASA’s InSight lander heading to Mars.
The two-stage rocket was assembled in three
pieces, beginning with the stacking of the
Atlas 5’s first stage booster March 3 at
Space Launch Complex 3-East.
The first stage’s RD-180 main engine will
burn a mixture of kerosene and liquid oxygen
to send the InSight spacecraft out of the
Earth’s atmosphere during the first four
minutes of the flight.
The Atlas 5’s Centaur upper stage, powered
by an Aerojet Rocketdyne RL10 engine, was
installed on top of the first stage March
6.
The Centaur engine, consuming liquid hydrogen
and liquid oxygen, will dispatch the InSight
probe with enough velocity to escape Earth’s
gravity and head for Mars.
Two days later, on March 8, a boattail structure
was added to the top of the Centaur stage.
The boattail provides an aerodynamic and structural
connection between the Centaur and the Atlas
5’s payload fairing, which will be lifted
on top of the rocket with the InSight spacecraft
next month.
Liftoff is scheduled for May 5 during two-hour
launch window that opens at 4:05 a.m. PDT
(7:05 a.m. EDT; 1105 GMT).
The InSight mission has until June 8 to depart
Earth, a month-long period determined by the
planetary positions of Earth and Mars in the
solar system.
Built by Lockheed Martin, InSight will reach
Mars on Nov. 26, using a heat shield, a supersonic
parachute and retro-rockets to steer toward
a soft touchdown on Elysium Planitia, a broad
equatorial plain.
Once on the ground, the lander will survey
its surroundings with cameras, then use its
robotic arm to place a seismometer instrument
on the surface to listen for tremors that
could provide clues about the red planet’s
deep interior.
