Parker Solar Probe facts for kids

Quick facts for kids
Parker Solar Probe

Model of the Parker Solar Probe
Names	Solar Probe (before 2002) Solar Probe Plus (2010–2017) Parker Solar Probe (since 2017)
Mission type	Heliophysics
Operator	NASA / Applied Physics Laboratory
Mission duration	7 years (planned) Elapsed: 6 years, 5 months and 12 days
Spacecraft properties
Manufacturer	Applied Physics Laboratory
Launch mass	685 kg (1,510 lb)
Dry mass	555 kg (1,224 lb)
Payload mass	50 kg (110 lb)
Dimensions	1.0 m × 3.0 m × 2.3 m (3.3 ft × 9.8 ft × 7.5 ft)
Power	343 W (at closest approach)
Start of mission
Launch date	12 August 2018, 07:31 UTC
Rocket	Delta IV Heavy / Star-48BV
Launch site	Cape Canaveral, SLC-37
Contractor	United Launch Alliance
Orbital parameters
Reference system	Heliocentric orbit
Semi-major axis	0.388 AU (58.0 million km; 36.1 million mi)
Perihelion	0.046 AU (6.9 million km; 4.3 million mi; 9.86 R☉)
Aphelion	0.73 AU (109 million km; 68 million mi)
Inclination	3.4°
Period	88 days
Sun
The official insignia for the mission. Large Strategic Science Missions Heliophysics Division ← Magnetospheric Multiscale Mission

The Parker Solar Probe (PSP; previously Solar Probe, Solar Probe Plus or Solar Probe+) is a NASA space probe launched in 2018 with the mission of making observations of the outer corona of the Sun. It will approach to within 9.86 solar radii (6.9 million km or 4.3 million miles) from the center of the Sun, and by 2025 will travel, at its closest approach, as fast as 690,000 km/h (430,000 mph) or 191 km/s, which is 0.064% the speed of light. It is the fastest object ever built on Earth.

The project was announced in the fiscal 2009 budget year. Johns Hopkins University Applied Physics Laboratory designed and built the spacecraft, which was launched on 12 August 2018. It became the first NASA spacecraft named after a living person, honoring physicist Eugene Newman Parker, professor emeritus at the University of Chicago.

A memory card containing names submitted by over 1.1 million people was mounted on a plaque and installed below the spacecraft's high-gain antenna. The card also contains photos of Parker and a copy of his 1958 scientific paper predicting important aspects of solar physics.

On 29 October 2018, at about 18:04 UTC, the spacecraft became the closest ever artificial object to the Sun. The previous record, 42.73 million kilometres (26.55 million miles) from the Sun's surface, was set by the Helios 2 spacecraft in April 1976. At its perihelion on 27 September 2023, the PSP's closest approach was 7.26 million kilometres (4.51 million miles), reaching this distance again on 29 March 2024. This will be surpassed after the remaining flyby of Venus.

On 24 December 2024 at 11:53 UTC, PSP is due to close its distance to 6.1 million km (3.8 million miles) from the surface of the Sun, its closest approach so far. It will next be able to transmit data back to Earth on 27 December.

Science goals

An apparent size of the Sun as seen from the Parker Solar Probe at perihelion compared to its apparent size seen from Earth

The goals of the mission are:

• Trace the flow of energy that heats the solar corona and accelerates the solar wind.
  1. How is energy from the lower solar atmosphere transferred to, and dissipated in, the corona and solar wind?
  2. What processes shape the non-equilibrium velocity distributions observed throughout the heliosphere?
  3. How do the processes in the corona affect the properties of the solar wind in the heliosphere?
• Determine the structure and dynamics of the plasma and magnetic fields at the sources of the solar wind.
  1. How does the magnetic field in the solar wind source regions connect to the photosphere and the heliosphere?
  2. Are the sources of the solar wind steady or intermittent?
  3. How do the observed structures in the corona evolve into the solar wind?
• Explore mechanisms that accelerate and transport energetic particles.
  1. What are the roles of shocks, reconnection, waves, and turbulence in the acceleration of energetic particles?
  2. What are the source populations and physical conditions necessary for energetic particle acceleration?
  3. How are energetic particles transported in the corona and heliosphere?

Mission

Launch of the Parker Solar Probe in 2018

Artist's rendition of the Parker Solar Probe approaching the Sun

The Parker Solar Probe was launched on 12 August 2018, at 07:31 UTC. The spacecraft operated nominally after launching. During its first week in space it deployed its high-gain antenna, magnetometer boom, and electric field antennas. The spacecraft performed its first scheduled trajectory correction on 20 August 2018, while it was 8.8 million kilometers (5.5 million mi) from Earth, and travelling at 63,569 kilometres per hour (39,500 mph)

Instrument activation and testing began in early September 2018. On 9 September 2018, the two WISPR telescopic cameras performed a successful first-light test, transmitting wide-angle images of the background sky towards the galactic center.

The probe successfully performed the first of the seven planned Venus flybys on 3 October 2018, where it came within about 2,400 kilometres (1,500 mi) of Venus in order to reduce the probe's speed and orbit closer to the Sun.

The second flyby of Venus on December 26, 2019. The velocity decreases by 2.9 km/s to 26 km/s (red circle), shifting the spacecraft to a new orbit closer to the Sun.

Within each orbit of the Parker Solar Probe around the Sun, the portion within 0.25 AU is the Science Phase, in which the probe is actively and autonomously making observations. Communication with the probe is largely cut off in that phase. Science phases run for a few days both before and after each perihelion. They lasted 11.6 days for the earliest perihelion, and will drop to 9.6 days for the final, closest perihelion.

Much of the rest of each orbit is devoted to transmitting data from the science phase. But during this part of each orbit, there are still periods when communication is not possible. First, the requirement that the heat shield of the probe be pointed towards the Sun sometimes puts the heat shield between the antenna and Earth. Second, even when the probe is not particularly near the Sun, when the angle between the probe and the Sun, as seen from Earth, is too small, the Sun's radiation can overwhelm the communication link.

After the first Venus flyby, the probe was in an elliptical orbit with a period of 150 days (two-thirds the period of Venus), making three orbits while Venus makes two. After the second flyby, the period shortened to 130 days. After less than two orbits, only 198 days later, it encountered Venus a third time at a point earlier in the orbit of Venus. This encounter shortened its period to half of that of Venus, or about 112.5 days. After two orbits it met Venus a fourth time at about the same place, shortening its period to about 102 days.

After 237 days, it met Venus for the fifth time and its period was shortened to about 96 days, three-sevenths that of Venus. It then made seven orbits while Venus made three. The sixth encounter, almost two years after the fifth, shortened its period down to 92 days, two-fifths that of Venus. After five more orbits (two orbits of Venus), it will meet Venus for the seventh and last time, decreasing its period to 88 or 89 days and allowing it to approach closer to the Sun.

Timeline

The speed of the probe and distance from the Sun, from launch until 2026

Findings

PSP observed switchbacks — traveling disturbances in the solar wind that caused the magnetic field to bend back on itself.

On November 6, 2018, Parker Solar Probe observed its first magnetic switchbacks – sudden reversals in the magnetic field of the solar wind. They were first observed by the NASA-ESA mission Ulysses, the first spacecraft to fly over the Sun's poles. The switchbacks generate heat that warms solar corona.

On 4 December 2019, the first four research papers were published describing findings during the spacecraft's first two dives near the Sun. They reported the direction and strength of the Sun's magnetic field, and described the unusually frequent and short-lived changes in the direction of the Sun's magnetic field. These measurements confirm the hypothesis that Alfvén waves are the leading candidates for understanding the mechanisms that underlie the coronal heating problem. The probe observed approximately a thousand "rogue" magnetic waves in the solar atmosphere that instantly increase solar winds by as much as 300,000 miles per hour (480,000 km/h) and in some cases completely reverse the local magnetic field.

They also reported that, using the "beam of electrons that stream along the magnetic field", they were able to observe that "the reversals in the Sun's magnetic field are often associated with localized enhancements in the radial component of the plasma velocity (the velocity in the direction away from the Sun's center)". The researchers found a "surprisingly large azimuthal component of the plasma velocity (the velocity perpendicular to the radial direction). This component results from the force with which the Sun's rotation slingshots plasma out of the corona when the plasma is released from the coronal magnetic field".

PSP discovered evidence of a cosmic dust-free zone of 3.5 million miles (5.6 million kilometres) radius from the Sun, due to vaporisation of cosmic dust particles by the Sun's radiation.

On April 28, 2021, during its eighth flyby of the Sun, Parker Solar Probe encountered the specific magnetic and particle conditions at 18.8 solar radii that indicated that it penetrated the Alfvén surface; the probe measured the solar wind plasma environment with its FIELDS and SWEAP instruments. This event was described by NASA as "touching the Sun".

On 25 September 2022, the first discovery of a comet was made in images from the Parker Solar Probe. The comet is named PSP-001. It was found by Peter Berrett, who participates in the NASA funded Sungrazer project. PSP-001 was discovered in images from 29 May 2022, part of the spacecraft's 12th approach to the Sun.

Since this discovery, a further 19 sungrazer comets have been discovered in the images taken by the Parker Solar Probe, including two non-group comets.

In 2024, it was reported that the probe detected a Kelvin-Helmholtz instability (KHI) during an observed coronal mass ejection. It is the first spacecraft that detected this long theorized event.

Images for kids

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  A light bar testing in the Astrotech processing facility.

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  The thermal testing of the spacecraft.

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  An apparent size of the Sun as seen from Parker Solar Probe at perihelion compared to its apparent size seen from Earth.

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  Schematic view of all PSP's instruments

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  Launch of Parker Solar Probe in 2018.

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  WISPR first light image. The right portion of the image is from WISPR's inner telescope, which is a 40-degree field of view and begins 58.5 degrees from the Sun's center. The left portion is from the outer telescope, which is a 58-degree field of view and ends about 160 degrees from the Sun.

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  The view from the probe's WISPR instrument on Sept. 25, 2018, shows Earth, the bright sphere near the middle of the right-hand panel. The elongated mark toward the bottom of the panel is a lens reflection from the WISPR instrument

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  Photo from the WISPR shows a coronal streamer, seen over the east limb of the Sun on Nov. 8, 2018, at 1:12 a.m. EST. The fine structure of the streamer is very clear, with at least two rays visible. Parker Solar Probe was about 16.9 million miles (21.2 million km) from the Sun's surface when this image was taken. The bright object near the center of the image is Mercury, and the dark spots are a result of background correction.

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  When Parker Solar Probe was making its closest approach to the Sun on June 7, 2020, WISPR captured the planets Mercury, Venus, Earth, Mars, Jupiter and Saturn in its field of view

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  Photo taken by the probe during its second Venus flyby, July 2020

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  As Parker Solar Probe flew by Venus on its fourth flyby, its WISPR instrument captured these images, showing the nightside surface of the planet

See also

In Spanish: Sonda Solar Parker para niños

• Living With a Star
• Advanced Composition Explorer, launched 1997
• List of vehicle speed records
• Solar and Heliospheric Observatory, launched 1995
• Solar Dynamics Observatory, SDO, launched 2010
• STEREO, launched 2006
• TRACE, launched 1998
• WIND, launched 1994
• Ulysses
• Spacecraft thermal control
• MESSENGER, Mercury orbiter (2011–2015) with sun shield
• Solar Orbiter, Sun-observing space probe developed by the European Space Agency (ESA) launched on 10 February 2020