Parker Solar Probe
Parker Solar Probe is humanity's closest visitor to the Sun - a mission to 'touch the star' that sustains us. Flying through the solar corona at 700,000 km/h, it studies the solar wind's origin and why the Sun's outer atmosphere is millions of degrees hotter than its surface.
Touching the Sun
Parker Solar Probe is named after Eugene Parker, who first predicted the solar wind in 1958. The spacecraft makes 24 orbits over 7 years, using 7 Venus gravity assists to gradually tighten its orbit around the Sun. At closest approach, it travels at 700,000 km/h - the fastest human-made object ever, fast enough to go from Earth to the Moon in under an hour.
Engineering Challenges
At 6.1 million km from the Sun (planned closest approach), the spacecraft experiences temperatures of 1,400°C on its Sun-facing side. A 11.4 cm carbon foam heat shield keeps the spacecraft instruments at room temperature. The shield must always face the Sun precisely - if tilted even slightly, the spacecraft would be destroyed within minutes.
Science Goals
- Solar Wind Origin: Trace solar wind plasma from corona to Earth
- Energy Transport: Understand how the corona is heated to 1,000,000°C
- Particle Acceleration: Study how particles are accelerated to high energies
- Magnetic Fields: Map the Sun's magnetic field in the corona
- Dust Environment: Measure dust in the inner solar system
Discoveries
- Magnetic Switchbacks: Swooping zigzag structures in the solar wind, like 'snakes' through space
- Space Weather Origins: First direct measurements near solar wind source regions
- Dust Detection: Found the predicted 'dust-free zone' near the Sun
- Coronal Mass Ejections: Observed CMEs up close with unprecedented detail
Communication
Parker communicates via a high-gain antenna with Earth at X-band (8 GHz). At closest approach, the spacecraft is limited to brief communication windows due to heat - the antenna must be pointed away from the Sun. Data rates range from 167 kbps at closest approach to 512 kbps at farthest distance. Signals take approximately 8 minutes to reach Earth at maximum distance.
Mission Profile
Parker Solar Probe will complete 24 orbits of the Sun between 2018 and 2025. The final orbit brings it within 6.1 million km of the solar surface - close enough to sample the corona directly. The mission ends when the spacecraft's hydrazine fuel is depleted, after which it will continue orbiting the Sun indefinitely.
Illustrations
