Parker Solar Probe Signals Successful Fifth Encounter of the Sun

On June 9, 2020, NASA’s Parker Solar Probe signaled the success of its fifth close pass by the Sun, called perihelion, with a radio beacon tone. The spacecraft completed the fifth perihelion of its mission two days prior, flying within 11.6 million miles from the Sun’s surface, reaching a top speed of about 244,225 miles per hour, which matches the spacecraft’s own records for closest human-made object to the Sun and fastest human-made object, set during its fourth orbit on January 29.

Mission controllers at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, received a “status A” beacon from the spacecraft at 4:40 p.m. EDT. Status A is the best of four possible status signals, and indicates that the spacecraft is operating nominally and the instrument suites are collecting science data. This beacon tone comes after a five-day period where communications with the spacecraft were not possible.

After completing the solar encounter on June 13, Parker Solar Probe will travel toward Venus for its third flyby of the planet — the first Venus flyby that will happen as the spacecraft travels away from the Sun, rather than towards the Sun. Parker Solar Probe will use Venus to shed some of its orbital energy and get much closer to the Sun on the following orbit. Passing at an altitude of approximately 516 miles above Venus’ surface — much lower than the previous two flybys but still well above Venus’ atmosphere — Parker Solar Probe will also witness a brief 11-minute solar eclipse during the maneuver while passing through the shadow of the planet.

Illustration of Parker Solar Probe making its fifth perihelion pass of the Sun
Parker Solar Probe made its closest approach to the Sun for its fifth orbit on June 7, 2020. Credit: NASA/Johns Hopkins APL/Steve Gribben

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

Data from this fifth observation campaign will be downlinked to Earth between late June and mid-August 2020, and will be released to the public in November 2020.

By Justyna Surowiec
Johns Hopkins University Applied Physics Lab

Parker Solar Probe Begins Longest Science Observation Campaign

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.

Parker Solar Probe approaching the Sun
Parker Solar Probe turned on its intstruments for its fifth solar flyby farther from the Sun than during previous encounters. Credit: NASA/Johns Hopkins APL/Steve Gribben

“We have a real opportunity here to see what’s going on in these regions further from the Sun’s corona,” said Nour Raouafi, Parker Solar Probe project scientist at the Johns Hopkins Applied Physics Laboratory. “While our primary goal is to understand the mysteries at the Sun’s corona and the ‘young’ solar wind closer to the Sun, there is evidence indicating very interesting physics to explore earlier in the orbit and link that to what occurs near the Sun. We have the capability to gather this data and see what it yields.”

The spacecraft will reach its closest point to the Sun for this orbit, called perihelion, on June 7. At perihelion, Parker Solar Probe will be about 11.6 million miles from the Sun’s surface, matching its own record for closest human-made object to the Sun set during its fourth orbit on Jan. 29.

After this solar encounter, the spacecraft will swoop by Venus for its first outbound flyby of the planet. This is when Parker Solar Probe will perform its third Venus gravity assist, which will allow the spacecraft to shed some of its orbital energy and get much closer to the Sun on the following orbit. Flying at an altitude of approximately 516 miles above Venus’ surface — much lower than the previous two flybys but still well above Venus’ atmosphere — Parker Solar Probe will also witness a brief 11-minute solar eclipse during the maneuver. All four instrument suites will be on and collecting data about the near-Venus environment and the planet’s night side during the flyby.

Data from this fifth observation campaign will be downlinked to Earth between late June and mid-August 2020, and will be released to the public in November 2020.

By Justyna Surowiec
Johns Hopkins University Applied Physics Lab

Data from Parker Solar Probe’s Third Orbit Now Available to the Public

NASA’s Parker Solar Probe team released a second collection of science data to the public on April 14, 2020. The release includes science data from all four of Parker Solar Probe’s instrument suites, spanning the mission’s third orbit around the Sun, which began on June 18, 2019 and completed on November 15, 2019. Also included are high-resolution measurements from the FIELDS and SWEAP instruments.

The data files and graphical displays can be accessed through NASA’s Space Physics Data Facility (SPDF) and Solar Data Analysis Center (SDAC), the APL Parker Solar Probe Gateway, and the Science Operation Centers of the four science investigation teams (the University of California, BerkeleyPrinceton UniversityHarvard-Smithsonian Center for Astrophysics; and Naval Research Laboratory.) Data from Parker Solar Probe’s first two orbits is also available.

Illustration of Parker Solar Probe facing the Sun
Artist’s concept of Parker Solar Probe approaching the Sun. Credit: NASA/Johns Hopkins APL/Steve Gribben

New findings from the mission’s first record-setting year in space were released in the Dec. 12, 2019 issue of the journal Nature and a special issue of the Astrophysical Journal Supplement Series. Parker Solar Probe’s observations reveal a complicated, active system near the Sun’s surface, including a notable phenomenon called switchbacks, which are traveling disturbances in the solar wind that cause the magnetic field to bend back on itself. These switchbacks may be a major source for the heating and acceleration of the solar wind plasma.

To date, Parker Solar Probe has completed four of its planned 24 orbits around the Sun. It will eventually travel within 4 million miles of the Sun’s surface, facing extreme heat and radiation. The mission seeks to provide new data on solar activity and how the solar corona works, which contributes significantly to our ability to forecast major space weather events that impact life on Earth. Parker Solar Probe launched in 2018 and will conduct its primary science mission until 2025.

By Justyna Surowiec

Johns Hopkins University Applied Physics Lab

New Wave of Parker Solar Probe Science Published

Researchers using Parker Solar Probe data released a new wave of research papers in a special supplement of The Astrophysical Journal on Feb. 3, 2020. The supplement, titled Early Results from Parker Solar Probe: Ushering a New Frontier in Space Exploration, includes some 47 papers with new findings based on the mission’s first three solar flybys. Several other papers still under review will be published later as part of this same issue. The introduction for the issue was written by Marcia Neugebauer, who first confirmed the existence of the solar wind after it was predicted by Eugene Parker — namesake of Parker Solar Probe — in 1958.

The new research builds upon initial results released in Nature and discussed at the American Geophysical Union meeting in December 2019.

A few highlights include:

Illustration of magnetic switchbacks in the solar wind, first discovered by Parker Solar Probe. Credit: NASA Goddard/CIL/Adriana Manrique Gutierrez
Illustration of magnetic switchbacks in the solar wind, first discovered by Parker Solar Probe. Credit: NASA Goddard/CIL/Adriana Manrique Gutierrez
  • New analysis of the magnetic switchbacks first discovered by Parker Solar Probe and described in Nature in Dec. 2019 (Dudok de Wit, et al)
  • Detailed studies of the slow solar wind, the origins of which are still uncertain, using Parker Solar Probe and other NASA and ESA spacecraft (Rouillard, et al)
  • New observations of a coronal mass ejection, observed close to the Sun by Parker Solar Probe and from afar by other NASA missions  (Wood, et al)
  • Close measurements of an energetic particle event by Parker Solar Probe and other NASA spacecraft (Leske, et al)

Read coverage of additional research from University of New Hampshire, Queen Mary University of London, the University of Alabama in Huntsville and Southwest Research Institute.

Parker Solar Probe Reports Successful Record-Setting Fourth Close Encounter of the Sun

NASA’s Parker Solar Probe is healthy and operating as designed following its fourth close approach to the Sun, called perihelion, on Jan. 29.

Mission controllers at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, received a “status A” beacon from the spacecraft at 5:20 a.m. EST on Feb. 1. Status A is the best of four possible status signals, and indicates that the spacecraft is operating nominally and the instrument suites are collecting science data. This status also indicates that any minor issues that may have occurred were identified and resolved by Parker Solar Probe’s onboard autonomy and fault management systems.

During this perihelion, Parker Solar Probe broke its own records for speed and proximity to the Sun for a human-made object. The spacecraft reached a speed of 244,255 miles per hour (about 393,044 kilometers per hour) as it whipped around the Sun at a distance of 11.6 million miles (about 18.6 million kilometers).

Parker Solar Probe’s heat shield, called the Thermal Protection System, or TPS, reached new record temperatures as well. At this distance from the Sun, computer modeling estimates show that the Sun-facing side of the TPS experienced a blazing 1,134 degrees Fahrenheit (612 degrees C), about 300 degrees hotter than encountered on the spacecraft’s previous three perihelia. The spacecraft and instruments behind this protective heat shield remained at a temperature of about 85 F (30 C). During the spacecraft’s closest three perihelia in 2024-25, the TPS will see temperatures around 2,500 F (1,370 C).

As the mission team learns more about operations and conditions in this region of space, they have increased the amount of time the instruments are on and gathering data. Parker Solar Probe’s fourth solar encounter phase began on Jan. 23, and the spacecraft will continue to acquire science data through Feb. 29, beyond the originally-planned end of the solar encounter phase on Feb. 4. This solar encounter data will be downlinked to Earth beginning in March.

By Geoff Brown

Johns Hopkins University Applied Physics Lab

Parker Solar Probe Completes Fourth Closest Approach, Breaks New Speed and Distance Records

At 4:37 a.m. EST on Jan. 29, 2020, NASA’s Parker Solar Probe broke speed and distance records as it completed its fourth close approach of the Sun. The spacecraft traveled 11.6 million miles from the Sun’s surface at perihelion, reaching a speed of 244,225 miles per hour. These achievements topple Parker Solar Probe’s own previous records for closest spacecraft to the Sun — previously about 15 million miles from the Sun’s surface — and fastest human-made object, before roughly 213,200 miles per hour.

Parker Solar Probe will continue to fly ever closer to the Sun on its seven-year journey, exploring regions of space never visited before and providing scientists with key measurements to help unveil the mysteries of the solar corona and wind.

As with most of Parker Solar Probe’s close approaches, the spacecraft is out of contact with Earth for several days around perihelion.

By Justyna Surowiec

Johns Hopkins Applied Physics Lab

Parker Solar Probe Prepares for New Science, New Records on Fourth Solar Orbit

NASA’s Parker Solar Probe began its fourth solar encounter today at 9:00 a.m. EST, at a distance of about 23.3 million miles from the Sun’s surface. It will reach perihelion, its closest distance to our star, during this orbit on Jan. 29 at about 4:30 a.m. EST.

Plot of Parker Solar Probe's position on Jan. 23, 2020, as it approaches the Sun.
Parker Solar Probe began its fourth solar encounter on Jan. 23, 2020. Track the spacecraft’s speed and position online.

The fourth perihelion will send the spacecraft within 11.6 million miles of the Sun, closer than its first three perihelia, which were at about 15 million miles from the Sun. The spacecraft’s four instrument suites will acquire data in this new environment, sampling this previously unexplored region around the Sun and potentially revealing new information about the solar wind and atmosphere.

Parker Solar Probe’s first three orbits of the Sun were all approximately the same distance from our star. Following the mission’s second Venus flyby on Dec. 26, 2019, and after one trajectory correction maneuver on Jan. 10, the spacecraft will set new records for distance from the Sun and fastest human-made object during its fourth perihelion; both records are currently held by Parker Solar Probe.

By Geoff Brown

Johns Hopkins Applied Physics Lab

Parker Solar Probe Completes Second Venus Flyby

On Dec. 26, Parker Solar Probe successfully completed its second flyby of Venus. The spacecraft used Venus to slow itself down, approaching the planet at a distance of about 1,870 miles from Venus’s surface during the second gravity assist of the mission. This gravity assist maneuver adjusted Parker Solar Probe’s trajectory to set it up for its fourth orbit around the Sun, or perihelion, which will occur on January 29, 2020. The flight operations team will use the data collected during the recent flyby to make adjustments for the remaining five Venus gravity assists which will occur over the course of the seven-year mission.

First Parker Solar Probe Science Data Released to Public

On Nov. 12, 2019, NASA’s Parker Solar Probe team released scientific data collected during the spacecraft’s first two solar orbits to the general public.

Data can be accessed through the NASA Space Physics Data Facility, the Solar Data Analysis Center, the APL Parker Solar Probe Gateway, and the Science Operation Centers of the four science investigation teams (the University of California, Berkeley; Princeton University; Harvard-Smithsonian Center for Astrophysics; and Naval Research Laboratory.) The newly released data, in the form of data files and graphical displays, is available for interested public users to manipulate, analyze, and plot in any way they choose.

A black and white image with a background of stars and bright ray-like structures extending from the left side of the frame.
Data from the Wide-field Imager for Solar Probe (WISPR) instrument on board Parker Solar Probe captured during the spacecraft’s first solar encounter in November 2018. Credit: NASA/Naval Research Laboratory/Parker Solar Probe

The released encounter data encompasses measurements made during the first two solar encounters, spanning the time between Oct. 31 and Nov. 12, 2018, and March 30 and April 19, 2019, when the spacecraft was within 0.25 AU of the Sun, as well as data collected at farther distances. One AU, or astronomical unit, is about 93 million miles, the average distance between the Sun and Earth.

Science teams led by principal investigators from partner institutions have been busy poring over the wealth of information collected by Parker Solar Probe in preparation for the mission’s first science results, to be released later this year. The four instrument suites onboard – FIELDS, ISʘIS, SWEAP, and WISPR – have been observing the characteristics of the solar wind (fields, waves, flows, and particles) in the immediate environment surrounding the Sun, called the corona.

“Parker Solar Probe is crossing new frontiers of space exploration, giving us so much new information about the Sun,” said Parker Solar Probe Project Scientist Nour E. Raouafi, from the Johns Hopkins Applied Physics Laboratory, or APL, in Laurel, Maryland, which manages the mission for NASA. “Releasing this data to the public will allow them not only to contribute to the success of the mission along with the scientific community, but also to raise the opportunity for new discoveries to the next level.”

With three of 24 planned solar orbits under its belt, Parker Solar Probe will continue to get closer to the Sun in the coming years, eventually swooping to within 4 million miles of the Sun’s surface, facing heat and radiation like no spacecraft before it. The mission seeks to provide new data on solar activity and how the solar corona works, which contributes significantly to our ability to forecast major space weather events that impact life on Earth. The mission launched in 2018 and is slated to perform its primary science mission until 2025.

By Justyna Surowiec

Johns Hopkins University Applied Physics Lab

Parker Solar Probe Completes Third Close Approach of the Sun

At just before 1:50 p.m. EDT on Sept. 1, 2019, NASA’s Parker Solar Probe completed its third close approach of the Sun, called perihelion. At the time of perihelion, the spacecraft was about 15 million miles from the Sun’s surface, traveling at more than 213,200 miles per hour.

Mission controllers at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, received a green “A” beacon from the spacecraft soon after perihelion, meaning all systems were performing as designed and that the spacecraft was in good health.

Plot showing Parker Solar Probe's orbit, with the spacecraft near perihelion.
Parker Solar Probe achieved its third perihelion, or close approach to the Sun, on Sept. 1, 2019. Track Parker Solar Probe’s current speed and position online.

This third encounter, which was at approximately the same distance from the Sun and speed as the first two, differs in that the spacecraft’s four instrument suites have been on and gathering data for a longer period than other perihelia.

For this third solar encounter, the mission team turned on the instruments when the spacecraft was around 0.45 astronomical units from the Sun on the inbound side of its orbit. (One astronomical unit, or AU, is about 93 million miles, the average distance between the Sun and Earth.) The instruments will be turned off when Parker Solar Probe is about 0.5 AU from the Sun on the outbound side, which will occur on about Sept. 20. For the prior two perihelia, the instruments were on from 0.25 AU prior to and after completing the close approach.

By Geoff Brown

Johns Hopkins University Applied Physics Lab