Betelgeuse

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

IR Andromeda

Cool_AndromedaThis view of the Andromeda galaxy from the Herschel space observatory shows relatively cool lanes of forming stars. Herschel was sensitive to the far-infrared light from cool dust mixed in with the gas where stars are born. This image reveals some of the very coldest dust in the galaxy (colored red here) that is only a few tens of degrees above absolute zero. Warmer regions such as the densely populated central bulge, home to older stars, appear as blue. Star-formation zones are in the spiral arms with several concentric rings interspersed with dark gaps where star formation is absent.

Andromeda (aka M31) is the nearest major galaxy to our own Milky Way about 2.5 million light-years away. Herschel was a European Space Agency mission.

Image Credit: ESA

A Cosmic Keyhole

V380 Orionis is a reflection nebula, a cloud of dust and gas illuminated by a young star. At its center is an inky black region that appears like a keyhole into a darkened space beyond the nebula. When the Hubble telescope took this image in 1999, it wasn’t clear if the apparent keyhole was an actual hole through the nebular material, or a dark mass of particularly cold gas or dust. Subsequent observations by the Herschel Space Observatory confirmed that the keyhole really is a hole offering a view to space on the far side of the nebula.

Video Credit: ESA

Another Stellar Nursery

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.

Image Credit: ESA

A Stellar Nursery

This infrared view (click the image to embiggen it) made by the Herschel Space Observatory of Cygnus X spans some 6×2 degrees of one of the closest, massive star forming regions in the plane of our Milky Way galaxy. The rich stellar nursery already holds the massive star cluster known as the Cygnus OB2 association. Those stars are more evident by the region cleared by their energetic winds and radiation near the bottom center of the picture. They can’t be detected by Herschel instruments operating at long infrared wavelengths, but Herschel does reveal the region’s complex filaments of cool gas and dust around the locations where new massive stars are forming. Cygnus X lies some 4500 light-years away toward the heart of the northern constellation of the Swan. This picture covers a view about 500 light-years wide.

Image Credit: ESA

Cool Andromeda

Cool_AndromedaThis view of the Andromeda galaxy from the Herschel space observatory shows relatively cool lanes of forming stars. Herschel was sensitive to the far-infrared light from cool dust mixed in with the gas where stars are born. This image reveals some of the very coldest dust in the galaxy (colored red here) that is only a few tens of degrees above absolute zero. Warmer regions such as the densely populated central bulge, home to older stars, appear as blue. Star-formation zones are in the spiral arms with several concentric rings interspersed with dark gaps where star formation is absent.

Andromeda (aka M31) is the nearest major galaxy to our own Milky Way about 2.5 million light-years away. Herschel was a European Space Agency mission active from 2009 to 2013.

Image Credit: ESA

Acquisitions and Mergers

This video starts with data from a survey of galaxies (blue and green) done by ESA’s Herschel Space Observatory and zooms in on a source that astronomers found interesting. The zooming in continues using observations performed with the Atacama Pathfinder Experiment (APEX; red). Finally, the video shows further observations obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) at higher resolution. Those observations revealed that the interesting source isn’t an ancient, massive galaxy, but of a pair of distinct massive galaxies about to merge. These two galaxies, each roughly as massive as our Milky Way, were informally dubbed the ‘Horse’ and the ‘Dragon’.

Video Credit: ESA

Herschel’s View of the Eagle Nebula

Herschel_Eagle_Nebulapillars6_hst_960The 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.

Image Credit: ESA

International Crab

International CrabThe Crab nebula is the remnant of a supernova explosion recorded by Chinese astronomers in the year 1054. This is composite view of the Crab nebula was assembled using data from the Herschel Space Observatory and the Hubble Space Telescope. Herschel is a European Space Agency (ESA) mission with important NASA contributions, and Hubble is a NASA mission with important ESA contributions.

Hubble‘s view of the nebula at visible wavelengths used three different filters sensitive to the emission from oxygen and sulphur ions and is shown here in blue. Herschel’s far-infrared image reveals the emission from dust in the nebula and is shown here in red.

Image Credit: ESA/NASA

A Not-So-Empty Hole

Lockman's HoleThere’s an area in the night sky called the “Lockman Hole.” It’s found in the constellation of Ursa Major (The Big Bear; the Big Dipper forms the lower body and tail of the larger constellation.) This “hole” appears almost empty to the naked eye and small telescopes. Regions like this one are almost completely devoid of objects in our Milky Way galaxy. With little local clutter in the way the Lockman ideal for studying galaxies in the distant universe.

Here’s what this empty part of the sky looked like when it was surveyed in infrared light by the Herschel Space Observatory. All of the little dots in this picture are distant galaxies. Their collective light is known as the cosmic infrared background. By studying this pattern, astronomers were able to measure various effects of dark matter.

Image credit: ESA

Betelgeuse

betelgeuse_bow_shockThe supergiant star Betelgeuse, the bright red star in Orion’s shoulder, is surrounded by an envelope of nearby material which is probably matter that it shed as it evolved into a supergiant. The arcs to the left in this image taken by the Herschel Space Observatory are material ejected from the star as it evolved into a red supergiant, and are shaped by its bow shock interaction as it move through the interstellar medium. The faint linear bar of dust on the left may represent a dusty filament connected to the local galactic magnetic field or the edge of an interstellar cloud. If so, then Betelgeuse’s motion across the sky implies that the arcs will hit the wall in 5,000 years time, and the star itself will smack into the wall 12,500 years later.

Image Credit: ESA

A Dwarf Galaxy

This infrared light picture of the Small Magellanic Cloud galaxy was assembled using data from the Herschel Space Observatory, a European Space Agency-led mission, and NASA’s Spitzer Space Telescope. The Large and Small Magellanic Clouds are the two biggest satellite galaxies of our home galaxy. They are considered dwarf galaxies compared to the big spiral of the Milky Way.

By combining data from Herschel and Spitzer, the irregular distribution of dust in the Small Magellanic Cloud becomes clear. A stream of dust called the galaxy’s “wing” extends to the left in the picture, and a vertical line of star formation is on the right.

The colors in this image indicate temperatures in the dust in the Cloud. Regions where star formation is at its earliest stages or is shut off are cooler. Warm spot occur around new stars heating surrounding dust. The coldest areas and objects are red, corresponding to infrared light taken up by Herschel’s at 250 microns (A micron is 0.000001 m). Herschel 100 and 160 micron data shown in green indicates warmer areas.1 The warmest spots appear in blue and are derived from 24 and 70 micron data from Spitzer.

Image Credit: ESA/NASA/JPL