A Beautiful Star Cluster for Dark Times

As many readers switch from Daylight Savings Time to find darker evenings awaiting them, here is a beautiful new image from the Hubble Space Telescope. We see a "globular cluster" with the catalog name M5 -- an ancient collection of stars, with about 100,000 of them visible on this remarkable photo.

The image combines views taken with visible light and infra-red cameras, and highlights some of the younger bluer stars sprinkled among the older yellower stars that make up the majority of the cluster. This grouping is about 25,000 light years away and was born 12-13 billion years ago.

It was about 100 years ago that Harlow Shapley, one of the greatest astronomers of the 20th century, used such bright globular clusters to map the extent and shape of our Milky Way Galaxy and to demonstrate conclusively that the Sun and the Earth were not in its center.

Such a beautiful picture can help remind us that there is a larger perspective out there, and help us put aside thoughts of the crazy things we seem to be doing to each other and to our fragile planet on almost a daily basis. Click on the pictures to see them bigger.  The diagram below shows how the globular clusters, distributed above and below the plane of our Galaxy, help outline its shape and extent.

New Hubble Image of Giant Star Nursery

The Hubble Space Telescope folks have just released a beautiful photo of a region where new stars are forming. Called by its catalog number, N11, this region of young stars and reddish glowing gas is in the Large Magellanic Cloud, one of the satellite galaxies that goes around our Milky Way. When you look at the image, bear in mind that the light we are seeing today from this galaxy left it 168,000 years ago. (In other words, the photo shows something 168,000 light years away.)

In the upper left corner, you can see the Rose Nebula, a tight round region in whose hidden center, new stars are being born right now. To give you a sense of scale, that little round gas cloud -- at the very top right -- is about 8 light years across.

In the middle of the image is the more extensive cloud of gas and young stars nicknamed the Bean Nebula (because of its shape.) Several generations of stars have been born in that cloudy region, and their adolescent energy has helped push the gas that gave birth to them into a larger and larger region.

Toward the bottom of the picture, you can see a jewel box of young bluish stars. Many are so hot they actually glow not just with blue and violet light, but with ultraviolet (what tanners call "black light.") Their energy has pushed for a while on any remaining gas from the cloud that gave them birth, so the neighborhood around them shows almost nothing of the reddish glow that signals warmer gas.

N11 is one of the largest nurseries for making stars we have ever observed. It's wonderful to have such a clear colorful image of the whole area, thanks to the remarkable instruments aboard the Hubble.

(And a personal note: the catalog number N11 is from a list of such glowing nebulae first put together in the 1950's by astronomer Karl Henize. Later in life, Henize became a Shuttle astronaut, and when it was his turn to go to space, he was a member of the Board of Directors of the Astronomical Society of the Pacific, where I was the Executive Director. He found that he had enough room in his personal kit to take a banner for the Society into space with him. We didn't have a banner, but when he offered, we of course made one up, real fast. He brought it back from space and presented it to me in a wonderful ceremony at the Society's headquarters (see photo below). It still has a place of pride on the walls of the Society's building in San Francisco.)