# Psyche by NASA

Canonical page: https://technooptimist.io/spaceflight/psyche
Frontier: [Spaceflight](https://technooptimist.io/spaceflight.md) · Field: Planetary missions · Company: [NASA](https://technooptimist.io/companies/nasa.md)
Stage: Deploy (4 of 5: Research → Proto → Pilot → Deploy → Scaling)
Updated: last update 2026-05-15, facts checked 2026-10-11
Goal: Visit a world that may be the exposed metal core of an early planet, to learn how rocky planets like Earth formed their iron cores, which we can never reach directly.
Status: Past its May 2026 Mars flyby, cruising on electric thrusters; reaches asteroid Psyche in August 2029.
Next milestone: Arrival and orbit insertion at Psyche, target Aug 2029 (slipped 43 months; originally Jan 2026)

## Milestones

| Status | Milestone | Date | Slip |
| --- | --- | --- | --- |
| Done | Selected for NASA's Discovery program | 4 Jan 2017 |   |
| Done | Launch on Falcon Heavy | 13 Oct 2023 | +21 mo (originally 2022) |
| Done | Laser link streams video from 31 million km | 11 Dec 2023 |   |
| Done | Switch to backup propellant line; thrusting resumes | 16 Jun 2025 |   |
| Done | Mars gravity-assist flyby | 15 May 2026 |   |
| Current | Arrival and orbit insertion at Psyche | Aug 2029 | +43 mo (originally Jan 2026) |
| Planned | End of prime mission (about 26 months in orbit) | Nov 2031 |   |

## Upcoming events

- **Aug 2029**: Arrival and orbit insertion at Psyche (slipped 43 mo)
- **Nov 2031**: End of prime mission (about 26 months in orbit)

## Most important updates

- **15 May 2026**: Psyche flies past Mars for a gravity assist toward the metal asteroid. Psyche passed about 2,864 miles (4,600 km) above Mars. ([our story](https://technooptimist.io/stories/psyche-flies-past-mars-for-a-gravity-assist-toward-the-metal-asteroid-20c39fb9.md) · [original source](https://www.scientificamerican.com/article/nasas-psyche-captures-gorgeous-mars-crescent-photo-on-way-to-asteroid/))
- **28 May 2025**: NASA's Psyche switches to its backup propellant line after a valve fault halts thrusting. Engineers paused Psyche's four electric thrusters in early April 2025 after a drop in xenon pressure, and traced it to a part inside one valve blocking the flow. ([our story](https://technooptimist.io/stories/nasa-s-psyche-switches-to-its-backup-propellant-line-after-a-valve-d6af6e71.md) · [original source](https://science.nasa.gov/blogs/psyche/2025/05/28/nasas-psyche-spacecraft-using-backup-fuel-line))
- **11 Dec 2023**: Laser experiment aboard Psyche streams video to Earth from 31 million km. NASA's Deep Space Optical Communications experiment, riding on Psyche, sent an ultra-high-definition video by laser from about 31 million km, some 80 times the Earth-Moon distance. ([our story](https://technooptimist.io/stories/laser-experiment-aboard-psyche-streams-video-to-earth-from-31-million-km-5afe4900.md) · [original source](https://www.jpl.nasa.gov/news/nasas-tech-demo-streams-first-video-from-deep-space-via-laser/))

## Current obstacles

- **Propellant line valve**: In April 2025 a valve fault blocked xenon flow and stopped thrusting. It now runs on the identical backup line, valve held open, with less redundancy left.

## Physics limits

- **Sunlight fades in the asteroid belt**: The asteroid belt is about three times farther from the Sun than Earth, so arrays that give about 20 kW near Earth give only about 2.3 kW at Psyche.
- **Low thrust means long trips**: Electric thrusters are efficient but weak, so reaching the asteroid belt takes about six years even with a planetary gravity assist.

## How it works

### Propulsion: Electric thrusters, almost always on

Solar power ionises xenon and electric fields fling the ions out fast. The push is about the weight of three coins, but it runs for months on little fuel.

### Route: A swing past Mars

In May 2026 the craft flew about 4,600 km above Mars, whose gravity added about 1,000 mph and tilted its path around the Sun by about 1 degree, for free.

### Science: Reading what the asteroid is made of

A gamma-ray and neutron spectrometer reads surface elements; a magnetometer seeks leftover magnetism from an ancient molten core; cameras map it.

### Mapping: Four orbits, closer each time

After arrival it moves between orbits from 700 km down to 75 km altitude over about two years, mapping shape, gravity and chemistry at ever finer detail.

## Spec sheet

| Spec | Psyche | Provenance |
| --- | --- | --- |
| Launch mass | 2,608 kg | reported |
| Xenon propellant | 922 kg | reported |
| Thrusters | 4 SPT-140 Hall-effect, up to 4.5 kW | reported |
| Specific impulse | 1,800 s | reported |
| Solar power | About 20 kW at Earth, 2.3 kW at Psyche | reported |
| Laser comms peak rate (demo) | 267 Mbps from 31 million km | reported |
| Asteroid size | About 220 km mean diameter | reported |
| Launch cost | $117M | reported |

Provenance: reported = stated by the company; estimated = our estimate; sample = a sample figure.

## About NASA

U.S. federal agency for civilian space exploration and aerospace research. NASA builds spacecraft (Orion for crewed Moon missions), rockets (SLS), and aircraft (X-59 quiet supersonic demonstrator) for scientific discovery.

- SLS and Orion are NASA's crewed lunar vehicles; Artemis II flew four astronauts around the Moon in April 2026.
- X-59 QueSST flew supersonic in 2026, proving shaped airframes produce quiet thumps instead of sonic booms.
- NASA cancelled the Lunar Gateway orbital station to focus on a permanent lunar surface base.

- Founded: 1958
- Headquarters: US
- Status: government
- Website: https://www.nasa.gov
- People: Bill Nelson (NASA Administrator)
- Partners, customers, investors: Lockheed Martin (partner); Northrop Grumman (supplier); Boeing (supplier)

Company page: https://technooptimist.io/companies/nasa.md

## Related programs

More from NASA:

- [X-59 QueSST](https://technooptimist.io/aviation/x-59-quesst.md) (Pilot)
- [Space Launch System (SLS)](https://technooptimist.io/spaceflight/space-launch-system.md) (Deploy)
- [Orion](https://technooptimist.io/spaceflight/orion-artemis.md) (Deploy)
- [Artemis Lunar Surface Base](https://technooptimist.io/spaceflight/artemis-lunar-surface-base.md) (Proto)
- [International Space Station & Deorbit Vehicle](https://technooptimist.io/spaceflight/international-space-station-deorbit.md) (Deploy)
- [Nancy Grace Roman Space Telescope](https://technooptimist.io/spaceflight/nancy-grace-roman-space-telescope.md) (Deploy)
- [Europa Clipper](https://technooptimist.io/spaceflight/europa-clipper.md) (Deploy)
- [SR-1 Freedom (Space Reactor-1)](https://technooptimist.io/spaceflight/sr-1-freedom.md) (Proto)

Everything in Spaceflight: https://technooptimist.io/spaceflight.md

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