Sparkling Hubble Space Telescope photo shows ancient globular cluster near Milky Way's heart

News
By
published

The cluster is estimated to be about 12 billion years old.

A Hubble Space Telescope image of the globular cluster Pismis 26 shows many thousands of stars from 23,000 light-years away.
countless bright stars scattered across frame and clustered at center (Image credit: NASA, ESA and R. Cohen (Rutgers the State University of New Jersey); Processing: Gladys Kober (NASA/Catholic University of America))

A sparkling new image from the Hubble Space Telescope captures the glow of thousands upon thousands of stars in an ancient globular cluster near the heart of the Milky Way. 

A globular cluster is a massive collection of stars pulled in close and tied together by their mutual gravitation, with many stars only a light-year or two away from their neighbors. The globular cluster in the new Hubble Space Telescope image, called Pismis 26, takes its name from astronomer Paris Pismis, who discovered the collection of stars at the Tonantzintla Observatory in Mexico in 1959. 

Related: Hubble Space Telescope delivers holiday sparkle in new image

The stars in Pismis 26 take on a nearly spherical structure. The cluster appears to contain predominantly red stars, with a smattering of brighter blue stars along the edges. These colors are due, in part, to the cluster's age, which is estimated at about 12 billion years, which means it contains many of the oldest stars in our galaxy, if not the universe. These stars are likely a much deeper red than the bright-blue ones that are typical of large, young, fast-burning stars that die out much sooner or the typical yellow star that straddles the line between the two.

The cluster is also heavily metallic, meaning that its stars contain higher levels of elements that are heavier than hydrogen and helium than stars like the sun do. Particularly, scientists think these stars are rich in nitrogen, which also suggests that the globular cluster's star population spans a range of ages, according to a NASA statement. 

Related stories:

— The best Hubble Space Telescope images of all time!

— Hubble telescope spots magnificent open star cluster 160,000 light-years away

— Mysterious globular clusters could unlock the secrets of galaxy formation

Additionally, part of the cluster's coloration comes from a phenomenon known as reddening, which is a result of dense stellar dust blocking shorter-wavelength blue light while allowing longer-wavelength red light to pass through more easily. 

Pismis 26 is located near the galactic bulge that surrounds Sagittarius A* (Sgr A*), the supermassive black hole at the heart of the Milky Way. This part of the galaxy is especially dust-heavy, thanks to the presence of Sgr A* and its incredible gravity, as well as that of all the material surrounding it in the bulge and the dense sphere of stars it contains. 

Follow us on Twitter @Spacedotcom or on Facebook.    

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community@space.com.

John Loeffler

 John is a science and technology journalist and Space.com contributor. He received his B.A. in English and his M.A. in Computer Science from the City University of New York, Brooklyn College, and has bylines with TechRadar, Live Science, and other publications. You can find him on Twitter at @thisdotjohn or seeking out dark sky country for spectacular views of the cosmos. 

4 Comments Comment from the forums
  • Turtle
    Do astronomers believe that these stars in this globular cluster around the galactic bulge have an equal chance of having life supporting planets as that of those in the spiral arms?

    How close to the galactic center could one get until life supporting planets would be too remote?
    Reply
  • Jon Wenzel
    Turtle said:
    Do astronomers believe that these stars in this globular cluster around the galactic bulge have an equal chance of having life supporting planets as that of those in the spiral arms?

    How close to the galactic center could one get until life supporting planets would be too remote?
    Pismis 26 is located near the galactic bulge that surrounds Sagittarius A* (Sgr A*), the supermassive black hole at the heart of the Milky Way.
    Pismis 26 is to close to Sagittarius A, a massive black hole, to be able to support any type of life . A massive black hole would create to much disturbance to allow life to evolve. The plasma jets of Sagittarius A would produce extreme amounts of radiation. The close proximity of the stars, one to two light years, would also create extremely large amounts of radiation. An extremely hostile location.
    We are located near the edge of the Milky Way on the Orion Arm at 25,640 light years from Sagittarius A.. If we were any closer to Sagittarius A, the radiation would kill us instantly.
    Have a good day.
    Live long and prosper.
    Reply
  • rod
    Interesting questions and observations in post #2 and #3. This site presently shows 5300 confirmed exoplanets. The Extrasolar Planets Encyclopaedia (exoplanet.eu)

    3906 are unique stars identified for all the exoplanets listed. The average distance is 776 pc, so most are relatively close to the Earth. The most distant is 11,000 pc. 1sigma is 1292 pc so the majority are fairly close to Earth.
    Reply
  • rod
    "Pismis 26 is located near the galactic bulge that surrounds Sagittarius A* (Sgr A*), the supermassive black hole at the heart of the Milky Way. This part of the galaxy is especially dust-heavy, thanks to the presence of Sgr A* and its incredible gravity, as well as that of all the material surrounding it in the bulge and the dense sphere of stars it contains."

    This is interesting too. The GC is said to be 12 billion years old yet some stars moving around Sgr A* are clearly very young due to fast orbits and velocities. Such age differences can be reconciled by postulating a number of GC orbits around the MW while much later, some young stars evolved around Sgr A*. Intriguing finds.
    Reply