Overview

The Parker Solar Probe is a NASA robotic spacecraft designed to fly into the Sun's outer atmosphere (the corona) and make the closest in situ measurements of the solar environment ever attempted. Launched in August 2018, the mission aims to sample the plasma, magnetic fields and energetic particles near the Sun and to improve understanding of how the corona is heated and how the solar wind is accelerated. For an official mission overview see the mission page.

Key characteristics

The spacecraft is protected by a reinforced carbon–carbon heat shield that keeps instruments at near-room temperatures while the front faces temperatures of thousands of degrees. At closest approach it will pass to within about 8.86 solar radii — roughly 6.2 million kilometers (3.85 million miles) from the Sun's "surface" — and will reach record speeds (around 700,000 km/h or 430,000 mph). The probe was launched on a heavy-lift vehicle; technical and launch details are available via the launch information resources.

Scientific instruments

Parker carries four instrument suites that work together to measure the local environment and image the corona:

  • FIELDS — measures electric and magnetic fields and waves.
  • SWEAP — counts and characterizes solar wind electrons, protons and heavier ions.
  • WISPR — a visible-light imager that captures the structure of the corona and solar wind.
  • ISʘIS (Integrated Science Investigation of the Sun) — detects energetic particles from the Sun.

Mission profile and trajectory

The probe follows an elliptical orbit that repeatedly brings it closer to the Sun. A series of gravity assists at Venus gradually lower the spacecraft's perihelion so it can sample progressively nearer regions of the corona. That trajectory strategy allows multiple close approaches without carrying prohibitively large amounts of fuel.

Scientific goals and importance

Major objectives include solving why the corona is millions of degrees hotter than the Sun's visible surface, discovering the mechanisms that accelerate the solar wind, and tracing how energetic particles are produced and propagated. In situ measurements taken within the corona complement remote solar observations and improve models that help predict space weather and its effects on Earth and spacecraft.

Notable facts and legacy

Parker Solar Probe is the fastest human-made object and the first NASA spacecraft named for a living person, honoring astrophysicist Eugene N. Parker for his work on the solar wind. Its findings are already reshaping ideas about fine-scale magnetic structures and plasma behavior near the Sun. For background on the Sun and the corona see the corona overview and general solar resources at the Sun information. Data and mission updates can be accessed through the data and science portals.