Betelgeuse is a red supergiant star, one of the largest visible to the naked eye. It is usually the tenth-brightest star in the night sky and the second-brightest in the constellation of Orion. It is a semiregular variable star with an apparent magnitude varying between +0.0 and +1.6. It has the widest range of brightness displayed by any first-magnitude star.
Beginning in October, 2019, Betelgeuse began to dim noticeably, and by February, 2020, its brightness had dropped from magnitude 0.5 to 1.7, a factor of 3. It then returned to more normal brightness by April, 2023. Observations using the Hubble Space Telescope suggest that dust created by a surface mass ejection was the cause of the unusual dimming.
The image above show Betelgeuse surrounded by a clumpy envelope of material in its immediate vicinity. It was taken by the Herschel Space Observatory in 2013.
Image Credit: ESA
This infrared view of the Andromeda galaxy from the Herschel Space Observatory show relatively cool lanes of gas where new stars are forming.
This false color image from infrared data taken by the Herschel Space Observatory shows a stellar nursery about 5,000 light-years away. These dust clouds are associated with the Rosette Nebula in the constellation Monoceros. The bright smudges are cocoons of dust surrounding massive embryonic stars, which will grow up to 10 times the mass of our Sun. The small spots near the center of the image are the embryos of less massive stars.
The famous Hubble Space Telescope image of the Pillars of Creation,the light-years long star forming columns of cold gas and dust inside the Eagle Nebula is inset on the left. This false-color composite image above shows the nearby stellar nursery using data from the Herschel Space Observatory. Herschel‘s far infrared detectors record the emission from the region’s cold dust directly. The famous pillars are included near the center of the scene.
