Parker completes 17th close fly-by of the Sun, setting new records

The Parker Solar Probe on September 27, 2023 completed its seventeenth close fly-by of the Sun, setting new speed and distance records.

Set up by a gravity-assist flyby of Venus on Aug. 21, the close approach (known as perihelion) occurred at 7:28 p.m. EDT, with Parker Solar Probe moving 394,736 miles per hour (635,266 kilometers per hour) around the Sun – another record. The milestone also marked the midway point in the mission’s 17th solar encounter, which began Sept. 22 and continues through Oct. 3.

It zipped past the Sun at a distance of only 4.51 million miles, also a record.

Whether it survived this fly-by will not be confirmed until October 1, when it is able to safely send its first data back after moving far enough away from the Sun to reopen communications.

Parker images the surface of Venus

Parker image compared to radar maps of Venus
For original images go here and here.

During its flybys of Venus in July 2020 and February 2021 the Parker Solar Probe used its wide field camera to take images of the night side of Venus in red optical and near infrared wavelengths, essentially measuring the heat (in the range of 863 degrees Fahrenheit) being emitted by the planet’s surface.

The resulting images, the first orbital photos of Venus’ surface in the optical, showed continent-sized surface details that matched previously made radar maps, and confirmed as expected that the higher altitudes are cooler than the lower.

The paper outlining these results can be read here.

The two pictures to the right compare previous radar maps (on the right) with the new Parker image (on the left). The central dark and cooler area is a region called Aphrodite Terra, which like Earth’s continents sits higher than the surrounding terrain.

Note that though cooler, the surface at these dark areas is still hellishly hot, more than 800 degrees Fahrenheit. Exploring the surface of Venus is going to be a far far far more challenging task that going to Mars.

Parker extends length of science operations during upcoming fifth solar fly-by

The science team for the Parker Solar Probe have decided to extend the period the spacecraft’s instruments are operating during its fifth close fly-by of the Sun, based on the data they have obtained from the first four fly-bys.

On May 9, 2020, NASA’s Parker Solar Probe began its longest observation campaign to date. The spacecraft, which has already completed four progressively closer orbits around the Sun, activated its instruments at a distance of 62.5 million miles from the Sun’s surface, some 39 million miles farther from the Sun than a typical solar encounter. The four instrument suites will continue to collect data through June 28, markedly longer than the mission’s standard 11-day encounters.

The nearly two-month campaign is spurred by Parker Solar Probe’s earlier observations, which revealed significant rotation of the solar wind and solar wind phenomena occurring much farther from the Sun than previously thought. The earlier activation of the science instruments allows the team to cover a larger range in order to trace the evolution of the solar wind as it moves away from the Sun.

Perihelion will occur on June 7 at a distance of 11.6 million miles from the Sun. That will match the previous record set during Parker’s previous orbit for the closest solar fly-by ever. They will then follow this with another fly-by of Venus, which will tighten the orbit even more.

Parker survives first close solar fly-by

The Parker Solar Probe has successfully survived its first close fly-by of the Sun.

Mission controllers at the Johns Hopkins University Applied Physics Lab received the status beacon from the spacecraft at 4:46 p.m. EST on Nov. 7, 2018. The beacon indicates status “A” — the best of all four possible status signals, meaning that Parker Solar Probe is operating well with all instruments running and collecting science data and, if there were any minor issues, they were resolved autonomously by the spacecraft.

At its closest approach on Nov. 5, called perihelion, Parker Solar Probe reached a top speed of 213,200 miles per hour, setting a new record for spacecraft speed. Along with new records for the closest approach to the Sun, Parker Solar Probe will repeatedly break its own speed record as its orbit draws closer to the star and the spacecraft travels faster and faster at perihelion.

It will be several weeks before they can download all the data gathered during this first fly-by.