Credit: ESA/Webb, NASA & CSA, M. Meixner
The James Webb Telescope has captured detailed information about the galaxy NGC 6822, one of our Milky Way’s closest neighbors. This metal-poor galaxy may hold the key to understanding the early Universe New Webb image shows irregular galaxy NGC 6822, captured by the Space Telescope’s Near Infrared Camera (NIRCam). NIRCam probes space using near-infrared light, allowing it to see stars through gas and dust.
The photo clearly demonstrates the power of Webb’s tools. The image shows NGC 6822’s vast, dense field filled with stars. No other telescope can see them through the layer of dust and gas. In the photo, they are only visible as faint red threads.
The brightest stars in the image are light blue and cyan. The bright blue ball in the lower left corner is especially visible: it is a globular cluster. Many background galaxies of various shapes and sizes are visible behind the stars. Galaxy NGC 6822 is located 1.6 million light years from Earth in the direction of the constellation Sagittarius. At one time, NGC 6822 played an important role in the history of astronomy. In 1925, Edwin Hubble, based on observations of Cepheids and bright diffuse nebulae, determined that it was more than 700,000 light-years away from the Milky Way.
Thus, NGC 6822 turned out to be the first object, other than the Magellanic Clouds, whose nature was determined to be extragalactic. This happened at a time when it was not known that other galaxies lay outside the Milky Way, and some astronomers determined that the size of the entire Universe was only 300,000 light years.