This "selfie" was created using a special lens inside the NIRCam instrument, which was designed to image segments of the primary mirror instead of images of the cosmos. This configuration is not used during scientific operations and is used solely for tuning purposes. In this case, the bright segment was pointing at the bright star, while the other segments were not looking in the same direction. This image provided an early indication of the primary mirror being aligned with the instrument.

Engineers are now confident that NIRCam is successfully receiving light, which is critical to its ultimate goal of helping to image objects in space. "NIRCam will be used for almost the entire length of the telescope's mirror alignment," NASA said. “However, it is important to note that NIRCam is operating well above its ideal temperature when capturing these initial engineering images, and visual artifacts can be seen in the mosaic.”

As Webb continues to cool, "artifacts" will shrink and the telescope will be better prepared for its work, NASA added. The telescope is designed to operate in the infrared (thermal) wavelength range, so it must be sufficiently cold to perform this operation.

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