Psyche
What is Psyche?
Probes & telescopes· Launched 2023-10-13 – arrives 2029 (under way). NASA's probe to (16) Psyche, an asteroid unusually rich in metal. Launched in 2023, it swung past Mars in May 2026 and is due to arrive in 2029.
Mission timeline
Spacecraft specs
| Launch | 2023-10-13 |
|---|---|
| Mars flyby | 2026-05 |
| Arrival | 2029, orbit of (16) Psyche |
| Propulsion | solar-electric Hall thrusters |
Figures are representative approximations. Source: compiled from NASA and IAU public data.
Asteroid 16 Psyche, found in Naples in 1852
(16) Psyche was discovered on 17 March 1852 by Annibale de Gasparis at the observatory in Naples, Italy. It is named after Psyche of Greek myth, a mortal woman loved by Eros who became the goddess of the soul. The 16 in brackets is its number in order of discovery; Ceres, the first asteroid found, is number 1.
When it was discovered, Psyche was just a small point of light like any other asteroid. Its metal-rich nature came to light more than a century later. Radar signals bounced off it much more strongly than off rocky asteroids, and the colours of its light also showed signs of metal. Psyche is one of the ten most massive asteroids in the main belt.
The mission in depth
The Psyche spacecraft was launched on 13 October 2023 on a Falcon Heavy rocket. Its target is the asteroid (16) Psyche in the main belt between Mars and Jupiter. Psyche is about 220 km across on average, roughly the length of the island of Cyprus. Most asteroids are made of rock, but radar and studies of its light suggest that Psyche contains a lot of metal such as iron and nickel.
Scientists are interested in Psyche because of planetary cores. Earth has a core of iron and nickel, but it is far too deep to see. One idea is that Psyche is the core of a small planet that lost its outer layers in collisions early in the solar system's history. Recent studies, however, suggest it may be a mix of metal and rock, so only a visit can settle the question.
Instead of burning fuel, the spacecraft uses Hall thrusters, which use electricity from solar panels to push out xenon gas. The push is tiny, about the weight of a few coins in your palm, but it keeps going for years and adds up to a large change in speed. In May 2026 the probe passed Mars, which bent its course.
The spacecraft also carried an experiment that sends data by laser. In April 2024 it transmitted data at 25 megabits per second from 1.5 times the Earth–Sun distance, about 220 million km. Psyche is due to arrive in August 2029 and spend about two years in orbit, studying the asteroid's magnetism, gravity and surface makeup.
Frequently asked
- When did Psyche launch?
- Psyche was launched on 2023-10-13.
- What is the next milestone for Psyche?
- Next for Psyche, on 1 Aug 2029: Psyche arrives at the metal asteroid.
- In one line, what is Psyche?
- Probes & telescopes — NASA's probe to (16) Psyche, an asteroid unusually rich in metal.
Related
Figures are representative approximations. Simulated positions use J2000 mean elements.