This Picture of the Week shows an open cluster known as NGC 2164, which was first discovered in 1826 by a Scottish astronomer named James Dunlop. NGC 2164 is located within one of the Milky Way galaxy's closest neighbours — the satellite galaxy known as the Large Magellanic Cloud. The Large Magellanic cloud is a relatively small galaxy that lies about 160 000 light-years from Earth. It is considered a satellite galaxy because it is gravitationally bound to the Milky Way. In fact, the Large Magellanic cloud is on a very slow collision course with the Milky Way — it’s predicted that they will collide 2.4 billion years from now.

The Large Magellanic Cloud only contains about one hundredth as much mass as the Milky Way, but it still contains billions of stars. The open cluster NGC 2164 is in good company in the Large Magellanic Cloud — the satellite galaxy is home to roughly 700 open clusters, alongside about 60 globular clusters. This image of NGC 2164 was taken by the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 (WFC3), which has previously imaged many other open clusters, including NGC 330 and Messier 11.

Credit:

ESA/Hubble & NASA, J. Kalirai, A. Milone

Coordinates
Position (RA):  	5 58 58.53
Position (Dec): 	-68° 31' 2.90"
Field of view:  	2.48 x 2.16 arcminutes
Orientation:    	North is 18.0° right of vertical

Colours & filters Band	Wavelength	Telescope
Ultraviolet UV  	225 nm	Hubble Space Telescope WFC3
Optical U       	336 nm	Hubble Space Telescope WFC3
Optical I       	814 nm	Hubble Space Telescope WFC3
Optical H-alpha 	656 nm	Hubble Space Telescope WFC3