Parker Solar Probe Completes Fourth Venus Flyby

Posted on 02/21/2021 15:14:32

NASA’s Parker Solar Probe sped past Venus on Feb. 20, using the planet’s gravity to shape its path for its next close approaches (or perihelia) to the Sun.

At just after 3:05 p.m. EST, moving about 15 miles (nearly 25 kilometers) per second, the spacecraft passed 1,482 miles (2,385 kilometers) above the surface as it curved around the planet. Such Venus gravity assists are essential to the mission to bring the craft progressively closer to the Sun; Parker Solar Probe relies on the planet to reduce its orbital energy, which in turn allows it to travel closer to the Sun – and inspect the properties of the solar wind at its source.

This was the fourth of seven planned Venus gravity assists. This Venus flyby served as an orbit maneuver applying a velocity change – called “delta-V” – on Parker Solar Probe, reducing its orbital speed by about 6,720 miles per hour (10,814 kilometers per hour). The maneuver changed the spacecraft’s orbit and set Parker Solar Probe up for its eighth and ninth close passes by the Sun, slated for April 29 and Aug. 9.

On each of those passes Parker Solar Probe will set records when it comes approximately 6.5 million miles (10.4 million kilometers) from the solar surface, about 1.9 million miles closer than the previous perihelion of 8.4 million miles (13.5 million kilometers) on Jan. 17.


– Mike Buckley, Johns Hopkins APL

Credit: NASA/Johns Hopkins APL/Steve Gribben