Happy New Year!

Sitting at home again, as we have done for many years... we'll make it to midnight only because we're waiting up for our youngest son!

I've often said that learning is important because the world is a fascinating place. As we hear over and over again about the 10 best this of the year and the ten worst that of the decade, NASA puts things in perspective.

The Hubble telescope provides us with this image of hundreds of thousands of stars moving about in the globular cluster M13, one of the brightest globular clusters in the northern sky. It can be found in the winter sky in the constellation Hercules, and can even be seen with the unaided eye under dark skies.

M13 is home to over 100,000 stars and is located at a distance of 25,000 light-years. In other words, the light in the picture left these stars in 22991 BCE! (For historical perspective, Abraham was ready to sacrifice Isaac in around 1800 BCE. Where will you be in 22991 CE?)

These stars are packed closely together in a ball approximately 150 light-years across, and they spend their entire lives whirling around in the cluster. Near the core, the density of stars is about a hundred times greater than the density in the neighborhood of our sun. These stars are so crowded that they can slam into each other and form a new star, called a "blue straggler." The brightest reddish stars in the cluster are ancient red giants. These aging stars have expanded to many times their original diameters and cooled. The blue-white stars are the hottest in the cluster.

M13 is one of nearly 150 known globular clusters surrounding our Milky Way galaxy. Globular clusters have some of the oldest stars in the universe. Scientists believe they formed before the disk of our Milky Way, so they are older than nearly all other stars in our galaxy including our own sun.

This image is a composite of archival Hubble data taken with the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys.

Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
Acknowledgment: C. Bailyn (Yale University), W. Lewin (Massachusetts Institute of Technology), A. Sarajedini (University of Florida), and W. van Altena (Yale University)