Which star is closest to Earth?

In the COSMOS catalogue the closest named destination is Proxima Centauri, at 4.246 ly, derived from its measured Gaia parallax.

Does COSMOS show what these stars look like?

No. It shows measured points with a bounded brightness and colour transfer. No stellar surface is resolved by the catalogue, so drawing a disc would be an invention.

Are these stars moving?

Yes, and the motion is measured. Positions are propagated linearly from the Gaia J2016.0 reference epoch using proper motion and, where published, radial velocity. COSMOS records a missing radial velocity as unknown rather than zero.

guide

Nearest stars in COSMOS: measured parallax, derived distance

COSMOS renders 371,766 measured Gaia DR3 sources inside 100 parsecs, and four of them are cross-identified with common names so you can fly straight to them. Their distances come from measured parallax.

Fly to a nearby star

Measured facts

Proxima Centauri: 1.302 pc · 4.246 lyMeasured parallax 768.0665 mas.
Barnard's Star: 1.828 pc · 5.963 lyMeasured parallax 546.9759 mas.
Wolf 359: 2.409 pc · 7.856 lyMeasured parallax 415.1794 mas.
Ross 128: 3.375 pc · 11.007 lyMeasured parallax 296.3053 mas.

How these distances are derived

Naive reciprocal of raw Gaia DR3 parallax for this positive, S/N >= 10 sample. No zero-point correction or Bayesian prior is applied.

The catalogue selects every Gaia DR3 source with parallax at least 10 mas, parallax signal-to-noise at least 10 and a non-null G magnitude inside 100 pc, then stores measured position, colour, proper motion and radial velocity where published. 371,766 of the 371,766 sources carry proper motion, and 169,709 carry a published radial velocity.

What you actually see

Each star is a measured point with a bounded brightness and colour transfer. COSMOS draws no stellar discs, because no catalogue in this volume measures one, and it does not imply surface structure.

Point size encodes nothing physical. It is clamped by the renderer so that faint sources stay visible as single pixels without turning magnitude into apparent size.

An honest note on "nearest"

COSMOS currently names only a small number of nearby stars as destinations. It does not claim that these are the nearest stars in existence: other nearby systems exist that are not yet cross-identified in this catalogue, and several are closer than some of the named entries here.

The catalogue contains eight other measured sources nearer than the most distant named landmark, and none nearer than Proxima Centauri. The named set exists so that search and narration have anchors. Everything else remains measured data without a popular name.

Questions this page answers

Which star is closest to Earth?: In the COSMOS catalogue the closest named destination is Proxima Centauri, at 4.246 ly, derived from its measured Gaia parallax.
Does COSMOS show what these stars look like?: No. It shows measured points with a bounded brightness and colour transfer. No stellar surface is resolved by the catalogue, so drawing a disc would be an invention.
Are these stars moving?: Yes, and the motion is measured. Positions are propagated linearly from the Gaia J2016.0 reference epoch using proper motion and, where published, radial velocity. COSMOS records a missing radial velocity as unknown rather than zero.

Content updated 2026-09-26. Every value on this page is computed from the shipped datasets; where a source publishes no value, the page says so instead of estimating one.