NASA Lucy Mission: Jupiter Trojan Asteroids Flybys Start in 2027

The NASA Lucy mission is about to turn from rehearsal to the main event. Launched in October 2021, the spacecraft is on a looping path to visit seven asteroids, most of them Jupiter Trojan asteroids that share Jupiter's orbit and have never been seen up close. The first Trojan encounter is planned for August 2027, so this is the right moment to understand what Lucy will do and why small bodies like these matter for anyone thinking about space resources.

What are Jupiter Trojan asteroids?

Jupiter Trojans are asteroids that travel in two swarms along Jupiter's orbit, one group leading the planet and one trailing it. They sit near stable gravity points, called Lagrange points, where they can remain for billions of years. Scientists think they may be leftover building material from the early solar system, which is why they are often described as fossils of planet formation.

Many Trojans look dark and reddish from far away, which suggests surfaces rich in carbon-bearing material. Up close data is the missing piece, and Lucy is designed to supply it.

The Lucy flyby schedule

Lucy has already completed two main-belt flybys that served as practice runs. The remaining plan, based on NASA and mission-team material, looks like this:

Sources give slightly different exact dates for the 2028 encounters, so check NASA's Lucy page for the current numbers.

What Lucy found at Donaldjohanson

On April 20, 2025, Lucy passed roughly 960 kilometers (about 600 miles) from Donaldjohanson, a small, elongated main-belt asteroid. The flyby tested the spacecraft's tracking system, which must keep cameras pointed at a fast-moving target while the craft itself moves at high speed. Early reporting described a roughly five-mile-long body with a narrow "neck" between two lobes, and later analyses have continued to be published, including a June 2026 summary of the research. Treat secondhand summaries with care and read the original papers when you can.

The practical lesson is that Lucy's autonomous targeting works, which is exactly what it needs for the Trojan encounters, where the targets are fainter and farther from the Sun.

What will Lucy measure at the Trojans?

Lucy carries instruments to answer several basic questions:

• Shape and surface: high-resolution cameras will map craters, ridges and boulders.
• Composition: infrared and thermal instruments will look for minerals, ices and carbon compounds.
• Mass and density: tracking the spacecraft's motion during a flyby reveals how massive each body is, which tells scientists whether it is solid rock or loosely packed rubble.
• Moons and binaries: Eurybates has a small companion, Queta, and the Patroclus-Menoetius pair orbit each other, so Lucy will study how such systems formed.

The mission will not land, drill or bring samples home. It is a survey, and surveys are how real exploration begins.

Why Trojan asteroids matter for asteroid mining

Nobody is going to mine Jupiter's Trojans anytime soon. They are far away, and reaching them takes years. But Lucy still matters for the resource question in three ways:

1. It tests how common volatile-rich bodies are. If Trojans are rich in water ice or organics, that changes estimates of how much usable material the solar system holds.
2. It improves our models of asteroid structure. Rubble pile or solid rock, the answer decides which extraction methods can work.
3. It proves cheap, autonomous reconnaissance. Mining needs prospecting first, and prospecting needs spacecraft that can find and measure targets without constant human control.

Closer targets, like near-Earth asteroids visited by Bennu and Ryugu samples, remain the realistic early candidates. For more on that, see our look at what Bennu's samples tell us about mining.

How this connects to Frontier

Frontier is a community-funded effort aimed first at asteroid resources, then Mars and Titan. Missions like Lucy are the kind of public science that makes a project like ours possible, because they turn guesses about distant bodies into measured facts. Frontier is built in public, with a fixed-supply token (FRNT) on Base and a treasury held in a multisig, so anyone can follow what is planned and what is funded. We read results like Lucy's closely, because good decisions about targets start with good data.

What to watch for next

• The Eurybates and Queta encounter in August 2027, the first ever close look at a Trojan.
• The Polymele flyby about a month later.
• Image releases and early papers from NASA and the Southwest Research Institute-led science team.
• Annual NASA budget decisions, which affect extended missions across planetary science.

Frequently asked questions

How many Jupiter Trojan asteroids are there? Astronomers have cataloged many thousands, and estimates suggest the total population of larger Trojans is comparable to the main asteroid belt in number of bodies above a given size. Exact counts keep rising as surveys improve.

When does Lucy reach its first Jupiter Trojan? The plan is Eurybates and its moon Queta on August 12, 2027, followed by Polymele on September 15, 2027.

Is Lucy going to land on or sample an asteroid? No. Lucy is a flyby mission. It will photograph and measure each target as it passes, but it will not land or collect samples.

Could Trojan asteroids be mined someday? Possibly in the very long term, but their distance makes them poor early targets. Near-Earth and main-belt asteroids are far more practical for the first mining attempts.