2MASS

The study's lead author, Lisa Garo from the European Southern Observatory in Chile, says the Garo 4 star cluster was detected by visually spotting a prominent clump of red giant stars in the Triple VX infrared imaging.

Further analysis using multiple survey databases, including the Third Guide Data Release, provided precise positions and motions of these stars, and the 2MASS survey provided supplementary infrared photometry.

Cluster member stars all move together through space in a similar direction or speed.

So the authors used this shared proper motion to statistically separate members of the cluster from unrelated foreground and background stars.

Curves during transits, dips in light that look nothing like a smooth, round planet.

Surveys analyzing data from wide-field space observatories like WISE, 2MASS, and GAIA are actively sifting through hundreds of thousands of stars searching for these exact thermodynamic anomalies.

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Gaia provides extraordinarily precise measurements of stars, including their distances and visible light.

The 2-micron All-Sky Survey, or 2MASS, covers the near-infrared.

And NASA's WISE mission surveyed the sky at longer infrared wavelengths, where warm dust and hypothetical alien waste heat can glow.

In a study published in 2024, the Project Hephaestus team began with roughly 5 million objects located within about 300 parsecs of Earth, or just under a thousand light years.