Captain's Quarters

[JD400]

James Webb Just Turned On Its Camera To Look At Its First Target

The Secrets of the Universe

The iconic James Webb Space Telescope has turned on its camera to look at its first target, star HD 84406, in the constellation of Ursa Major, the Great Bear. It's a sun-like star about 260 light-years away and is too dim to be seen with naked eyes. HD 84406 will help the telescope align its 18 honeycombed-shaped mirrors.

These images will be taken by Webb's most crucial camera - the NIRcam. The Near-Infrared Camera (NIRCam)will cover the infrared wavelength range of 0.6 to 5 microns. NIRCam has to first cool down to a temperature of just -237 ºC (36 K). It will detect light from the earliest stars and galaxies in the formation process, the population of stars in nearby galaxies, and young stars in the Milky Way and Kuiper Belt objects. It is also equipped with coronagraphs, which allow astronomers to take pictures of very faint objects around a central bright object like star systems.

NIRCam will keep staring at HD 84406 while Webb's optics experts move the mirror segments in nanometer-scale steps to create a perfectly smooth surface. This work is expected to last until late April. The first proper images will probably be released in late June or early July.