Parker Solar Probe Completes 21st Close Approach to the Sun

Parker Solar Probe Completes 21st Close Approach to the Sun
by Clarence Oxford
Los Angeles CA (SPX) Oct 05, 2024

NASA's Parker Solar Probe successfully completed its 21st close approach to the Sun on Sept. 30, matching its previous distance record by coming within 7.26 million kilometers (4.51 million miles) of the solar surface. This close approach, known as perihelion, occurred at 5:15 UTC (12:15 a.m. EDT), with the spacecraft traveling at an impressive speed of 635,300 kilometers per hour (394,700 miles per hour) around the Sun, once again matching its own record.

On Oct. 3, the spacecraft communicated with mission operators at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland - where it was also designed and built. The beacon signal indicated the spacecraft was in good health, and all systems were functioning normally.

This perihelion marked the midpoint of the Parker Solar Probe's 21st solar encounter, which began on Sept. 25 and will conclude on Oct. 5. It also marked the final time the spacecraft will fly around the Sun at this particular distance and speed before entering a phase of closer and faster approaches.

The spacecraft's next major milestone comes on Dec. 24, when Parker will execute the first of its three final and closest approaches to the Sun as part of its primary mission. After a final gravity assist from Venus on Nov. 6, Parker Solar Probe will approach the Sun at a distance of just 6.1 million kilometers (3.8 million miles) from its surface, moving at an increased speed of 692,000 kilometers per hour (430,000 miles per hour).

Parker Solar Probe Prepares for Final Venus Flyby
In preparation for the upcoming gravity assist, Parker Solar Probe performed a short course correction maneuver on Aug. 26. The spacecraft fired its small directional thrusters for about 17 seconds, adjusting its velocity by less than 1.6 kilometers per hour (1 mile per hour). This slight change ensured Parker would be on track for its seventh and final planned Venus flyby on Nov. 6. The correction altered its trajectory by about 593 kilometers (386 miles), bringing the spacecraft closer to its targeted flyby point, just 380 kilometers (240 miles) above Venus' surface.

Yanping Guo, mission design and navigation manager at APL, highlighted the importance of precise positioning and timing for the Venus flybys. These gravity assists play a key role in tightening Parker Solar Probe's orbit around the Sun. The upcoming flyby will be the closest of all the mission's Venus encounters and will be crucial for positioning the spacecraft for its ultimate mission goal - a record-breaking approach to within 6.1 million kilometers (3.8 million miles) of the Sun's surface.

"Venus 7 is the critical gravity assist for Parker Solar Probe to eventually achieve its minimum solar distance," Guo said. She also noted that the team may perform another smaller adjustment maneuver in late October or early November, following the Sept. 30 solar encounter, to fine-tune Parker's path to Venus.