Parker Solar Probe’s solar arrays have deployed. They will generate the electricity needed for the spacecraft during its mission. The spacecraft is in good health and operating on its own. Parker Solar Probe has begun its mission to “touch” the Sun.
We have spacecraft separation. Cheers and applause can be heard from the launch teams as the Parker Solar Probe separates from the United Launch Alliance Delta IV Heavy third stage. Next up is solar array deployment.
Main engine cutoff of the second stage and separation from the third stage has occurred. The third staged has ignited for its 80-second burn. The third stage is attached to NASA’s Parker Solar Probe.
The Delta IV Heavy second stage has fired its RL10 engine for the second and final time and is now in a coast phase. Next up is second stage separation.
The Delta IV Heavy second stage is firing its small thrusters to position itself and the Parker Solar Probe into the proper position to fire its main engine for the final time during the mission. Everything remains on schedule for the flight.
The Delta IV Heavy upper stage main engine has started its burn following on-time booster engine cutoff and booster separation. This is the first of two planned burns for the second stage engine during today’s ascent. The payload fairing has been jettisoned.
Booster ignition and liftoff of the United Launch Alliance Delta IV Heavy rocket at 3:31 a.m. EDT, from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, carrying NASA’s Parker Solar Probe.
About four minutes into flight, a series of key events occurs in rapid succession: Delta IV port and starboard booster engines shut down and separate, main booster engine cutoff, separation of the booster from the second stage, ignition of the second stage main engine, then jettison of the payload fairing.
The Parker Solar Probe countdown is underway toward a liftoff at 3:31 a.m. EDT. During the last four minutes of the countdown, the Delta IV Heavy propellant tanks will be brought up to flight pressure, the rocket and spacecraft will be confirmed on internal power, and the Eastern Range and launch managers will perform final status checks. A computerized autosequencer will take over the countdown in order to conduct a host of activities in precise order.
The launch countdown is in a T-4 minute hold. The launch team is proceeding toward launch of a United Launch Alliance Delta IV Heady rocket carrying Parker Solar Probe on a mission to the Sun.
Liftoff is scheduled for 3:31 a.m. EDT, at the beginning of a 65-minute launch window. The forecast is now at 95 percent chance for favorable weather conditions for launch.
In 2017, the mission was renamed for Eugene Parker, the S Chandrasekhar Distinguished Service Professor Emeritus, Department of Astronomy and Astrophysics at the University of Chicago. In the 1950s, Parker proposed a number of concepts about how stars–including our Sun–give off energy. He called this cascade of energy the solar wind, and he described an entire complex system of plasmas, magnetic fields, and energetic particles that make up this phenomenon. Parker also theorized an explanation for the superheated solar atmosphere, the corona, which is –contrary to what was expected by physics laws–hotter than the surface of the Sun itself. This is the first NASA mission that has been named for a living individual.