Finally, this past week, astronomers at Cambridge University made headlines when they said they'd spotted indications of possible life on a distant planet using data from the James Webb Space Telescope.

Now, another space-based observatory that's changed what we know about the universe is retiring.

The European Space Agency's craft

known as Gaia is leaving behind a legacy of stunning discoveries.

Gaia began its working life in 2013, launched with a clear mission, map our galaxy and tell its story.

The space observatory is equipped with an array of telescopes and instruments.

For more than a decade, it had slowly spun about a million miles from Earth,

charting the precise locations of nearly 2 billion stars.

I don't think anyone can imagine living without Gaia data anymore.

Astronomer Anthony Brown of Leiden University in the Netherlands

leads Gaia's data processing and analysis.

Because we have the positions and brightness and colors of 2 billion stars in the sky,

we can actually make a very beautiful all-sky map of the Milky Way.

But Gaia has helped create more than just beautiful maps.

Its data led to the revelation that 10 billion years ago,

the young Milky Way collided and merged with a smaller galaxy.

Scientists are still exploring the cosmic fallout.

A lot of the stars from that, let's say, intruder are still around, and we can identify them thanks to Gaia.

Gaia completed one of the most comprehensive celestial catalogs in history,

revealing more than half a million new stars within a cluster known as Omega Centauri.

Many of them zipped through space at several hundred thousand miles an hour.

So far, Gaia's data has been used in more than 13,000 studies.

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