It takes a lot of help to study one of the biggest mysteries in the universe: dark energy. An experiment at McDonald Observatory, for example, has used three supercomputers and the eyes of 10,000 volunteers to sift through more than 60 terabytes of data. That’s resulted in the project’s first catalog — more than 200,000 objects.
HETDEX — the Hobby-Eberly Telescope Dark Energy Experiment — is looking at a million galaxies in a small patch of sky that includes the Big Dipper. The galaxies are giving birth to a lot of stars. They’re about 10 billion light-years away, so HETDEX sees them as they looked when the universe was young.
The goal is to see how fast the galaxies were moving away from us at the time. That will help scientists determine how the effect of dark energy has changed over time — and perhaps what dark energy is. Dark energy makes the universe expand faster as it ages. But scientists don’t know what it is.
The HETDEX catalog covers observations from the project’s start, in 2017, through the middle of 2020. It includes more than 50,000 of the type of galaxy the project is studying. But it also includes about 135,000 other galaxies and many other objects.
In addition, online volunteers around the world have classified a quarter of a million galaxies in the HETDEX observations — results for future catalogs.
We’ll talk about another big-data project tomorrow.
Script by Damond Benningfield