StarDate

Spicy Clusters


Listen Later

The Gaia Sausage isn’t made with oregano or garlic or pepper flakes. Yet it’s plenty spicy. It appears to be a streamer of stars captured by the Milky Way billions of years ago. And it includes some of the biggest and oldest star clusters in the entire galaxy.

One of those clusters is Messier 2. It’s in Aquarius, and is in the southwest at nightfall. Through binoculars, the cluster looks like a small, fuzzy patch of light.

There’s nothing small about the cluster, though. It contains 150,000 stars, packed into a ball about 175 light-years in diameter. That makes it a globular cluster. And its stars are ancient: about 13 billion years old. That means they formed when the universe was less than a billion years old.

M2 has a lot in common with at least seven other globulars in the Milky Way. The clusters are spread through a region of space that’s shaped like a sausage. It’s named for the Gaia space telescope, which has mapped the region.

The eight clusters — and possibly two others — follow similar orbits through the galaxy. They’re the same age, and their stars have about the same composition — indications that the clusters had a common origin.

They may have formed in another galaxy. The galaxy rammed into the Milky Way at least eight billion years ago. Because the Milky Way was bigger, it absorbed the other galaxy — including its globular clusters. The clusters are now long-time residents of the Milky Way — and the Gaia Sausage.


Script by Damond Benningfield

...more
View all episodesView all episodes
Download on the App Store

StarDateBy Billy Henry

  • 4.6
  • 4.6
  • 4.6
  • 4.6
  • 4.6

4.6

251 ratings


More shows like StarDate

View all
Radiolab by WNYC Studios

Radiolab

43,883 Listeners

The 365 Days of Astronomy by 365DaysOfAstronomy.org

The 365 Days of Astronomy

348 Listeners

Planetary Radio: Space Exploration, Astronomy and Science by The Planetary Society

Planetary Radio: Space Exploration, Astronomy and Science

1,351 Listeners

SpaceTime with Stuart Gary by Stuart Gary

SpaceTime with Stuart Gary

321 Listeners

BirdNote Daily by BirdNote

BirdNote Daily

1,256 Listeners

Ask a Spaceman! by Paul M. Sutter

Ask a Spaceman!

836 Listeners

Astronomy Cast by Fraser Cain and Dr. Pamela Gay

Astronomy Cast

2,882 Listeners

Universe Today Podcast by Fraser Cain

Universe Today Podcast

570 Listeners

Space Nuts: Astronomy Insights & Cosmic Discoveries by Professor Fred Watson and Andrew Dunkley

Space Nuts: Astronomy Insights & Cosmic Discoveries

234 Listeners

Science Friday by Science Friday and WNYC Studios

Science Friday

6,437 Listeners

Short Wave by NPR

Short Wave

6,564 Listeners

The Supermassive Podcast by The Royal Astronomical Society

The Supermassive Podcast

330 Listeners

NASA's Curious Universe by National Aeronautics and Space Administration (NASA)

NASA's Curious Universe

886 Listeners

Why This Universe? by Dan Hooper, Shalma Wegsman

Why This Universe?

381 Listeners

Crash Course Pods: The Universe by Crash Course Pods, Complexly

Crash Course Pods: The Universe

572 Listeners