Psyche launch — to a metal world

Bound for the iron-nickel asteroid (16) Psyche — possibly the exposed core of a shattered protoplanet.

The moment of Psyche launch — to a metal world: https://nowsky.org/e/psyche-launch — opens at the right place and time, replayable, no login.

Available views: Orbit ✓ · Sky — (not visible in the sky)

The story

On 13 October 2023 the Psyche spacecraft left on a Falcon Heavy for the metal asteroid 16 Psyche. Rich in iron and nickel and 226 km across, it has long been proposed as the exposed core of a shattered protoplanet. If so, humanity will be looking from orbit at the heart of a planet — something Earth's own core can never allow.

The spacecraft cruises on Hall-effect electric thrusters expelling xenon — the first deep-space mission to use them as primary propulsion. The thrust is no more than the weight of a coin, but left on for years it delivers the same change in velocity as a chemical rocket for far less propellant.

It also carries the Deep Space Optical Communications experiment. In November 2023 it sent its first laser signal to Earth from 16 million km, and in April 2024 it transmitted at 25 megabits per second from 226 million km — 1.5 times the Earth–Sun distance — tens of times faster than radio.

After a Mars flyby in May 2026 it is due to arrive in August 2029. Psyche's density, about 4 g/cm³, sits between rock and metal, so whether it is half metal or mostly rock is the first question on arrival. The orbit view also shows 16 Psyche's orbit, so the moment the probe meets its target can be watched.

Why it matters

16 Psyche is the only candidate planetary core in the solar system that can be observed up close. The cores of Earth, Mars and Venus lie thousands of kilometres down and are known only from seismic waves. If Psyche really is the remnant of a core, how planets form their layers can be read directly from its surface.

Adopting electric propulsion as the main drive is a turning point in deep-space navigation. After Dawn first tested it in the asteroid belt in 2007, Psyche relies on ion engines for its whole five-year cruise combined with a Mars flyby, a pattern expected to become standard for asteroid and outer-planet missions in the 2030s.

The laser-communication success is the first demonstration toward solving the bandwidth problem of crewed Mars exploration. Radio cannot carry high-resolution video and voice from Mars distance in near real time; DSOC showed the alternative works.

How to watch

The Psyche spacecraft is beyond Mars's orbit on its way to the asteroid belt and cannot be seen from the ground. Select it in the orbit view for its current position and track, with the planned 2029 arrival point marked.

The orbit replay runs from the October 2023 launch through the 2026 Mars flyby to the meeting with 16 Psyche in August 2029; with asteroids switched on, the asteroid's five-year orbit is drawn as well and the probe can be seen catching up.

16 Psyche is 9th to 12th magnitude, a point in a small telescope that brightens near opposition. The sky view shows which constellation it is in now.

See this for yourself — replay the moment in the orbit view

Background

16 Psyche was the sixteenth asteroid found, discovered in 1852 by the Italian Annibale de Gasparis and named for the Psyche of Greek myth. Radar in the 1980s hinted at a metallic composition, and the mission was selected as a NASA Discovery mission in 2017.

Launch was originally set for August 2022 but slipped a year when flight-software testing ran late, pushing arrival from 2026 to 2029. In April 2024 a propellant-pressure problem halted thrusting for a month until a backup line was brought in.

Over 21 months after arrival the orbit is lowered in four stages from 700 km to 75 km while mapping and measuring the magnetic field, gravity and elemental composition. A remnant magnetic field found by the magnetometer would be evidence of a once-molten core.

FAQ

Is 16 Psyche really metal?

Its density is between rock and metal; whether it is half metal or mostly rock is the first question on arrival.

When does it arrive?

August 2029, after a Mars flyby in May 2026.

Why does laser communication matter?

It moves data from Mars distance tens of times faster than radio — a demonstration toward the bandwidth needed for crewed missions.

How weak is the electric thrust?

About the weight of a coin, but left on for years it gives the same velocity change as a chemical rocket for less propellant.

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Times and figures are approximate — verify with official sources when planning travel. Simulation uses J2000 mean elements.