Astronomers may have finally solved one of the weirdest mysteries of our night sky: why Betelgeuse, a massive star in the constellation Orion, seems to fade and brighten as if it were operated by a heavenly dimmer switch. Using the Hubble Space Telescope and ground-based observatories, scientists observed Betelgeuse for almost eight years and found that patterns in the star's light suggested the wake of another, unseen star was passing through its atmosphere.
This Hubble image features a trio of galaxies that appear to be very close together, but appearances can be deceiving. The large spiral galaxy at the bottom right is NGC 1356. The two apparently smaller spiral galaxies flanking it are LEDA 467699 ( top) and LEDA 95415 ( left).
NASA, ESA, I. Pasha, P. van Dokkum Day 16 of the 2025 Space Telescope Advent Calendar: The Bullseye. This recent image of LEDA 1313424, nicknamed the Bullseye Galaxy, was made by the Hubble Space Telescope.
Included in the study was NASA's SPHEREx space telescope, the European Space Agency's proposed ARRAKIHS system, and China's planned Xuntian space telescope, as well as Hubble, all of which orbit at altitudes between about 450 and 800 kilometers. The findings suggest about 39.6 percent of Hubble's images and 96 percent of images from the other three telescopes would be affected by interference from satellites.
