Hubble's view of dazzling globular cluster NGC 6397
This ancient stellar jewelry box, a globular cluster called NGC 6397, glitters with the light from hundreds of thousands of stars.
Astronomers used the NASA/ESA Hubble Space Telescope to gauge the cluster’s distance at 7800 light-years away. NGC 6397 is one of the closest globular clusters to Earth.
The cluster’s blue stars are near the end of their lives. These stars have used up their hydrogen fuel that makes them shine. Now they are converting helium to energy in their cores, which fuses at a higher temperature and appears blue.
The reddish glow is from red giant stars that have consumed their hydrogen fuel and have expanded in size.
The myriad small white objects include stars like our Sun.
This image is composed of a series of observations taken from July 2004 to June 2005 with Hubble’s Advanced Camera for Surveys. The research team used Hubble’s Wide Field Camera 3 to measure the distance to the cluster.
Credit:NASA, ESA, and T. Brown and S. Casertano (STScI)
Acknowledgement: NASA, ESA, and J. Anderson (STScI)
About the Image
NASA caption
| Id: | opo1824a |
| Type: | Observation |
| Release date: | 11 February 2021, 16:00 |
| Related releases: | heic2103 |
| Size: | 4924 x 3693 px |
About the Object
| Name: | NGC 6397 |
| Type: | Milky Way : Star : Grouping : Cluster : Globular |
| Distance: | 7800 light years |
| Constellation: | Ara |
| Category: | Star Clusters |
Image Formats
Wallpapers
Coordinates
| Position (RA): | 17 40 40.09 |
| Position (Dec): | -53° 40' 11.74" |
| Field of view: | 3.29 x 2.47 arcminutes |
| Orientation: | North is 0.1° left of vertical |
Colours & filters
| Band | Wavelength | Telescope |
|---|---|---|
| Optical B | 435 nm |
Hubble Space Telescope
ACS |
| Optical r | 625 nm |
Hubble Space Telescope
ACS |