New images from the NASA/ESA/CSA James Webb Space Telescope capture the barred spiral galaxy Messier 77 as a whirlpool of glowing dust, newborn stars and a brilliantly active core.
This image of Messier 77 from Webb’s Mid-Infrared Instrument (MIRI) highlights its swirling spiral arms, the dust in its disk and its piercingly bright core like never before. The bright orange lines appearing to radiate out from the galaxy’s center are not actually a feature of the galaxy: they are a type of distortion that arises from the optical design of the telescope. Called diffraction spikes, they are created because the intense light from the unresolved AGN is bent (diffracted) very slightly at the edges of Webb’s hexagonal mirror panels and around one of the struts that hold up its secondary mirror. Image credit: NASA / ESA / CSA / Webb / A. Leroy.
Located about 62 million light-years from Earth in the constellation of Cetus, Messier 77 is one of the brightest and best-studied galaxies in the night sky.
Also known as the Squid Galaxy, NGC 1068, LEDA 10266 and Cetus A, this galaxy has an apparent magnitude of 9.6.
Messier 77 was discovered by the French astronomer Pierre Méchain in 1780, who originally identified it as a nebula. Méchain then communicated the discovery to his colleague, French astronomer Charles Messier.
Messier believed that the highly luminous object he saw was a cluster of stars, but as technology progressed its true status as a galaxy was realized.
At 100,000 light-years across, Messier 77 is one of largest galaxies in the Messier catalogue — so massive that its gravity causes other nearby galaxies to twist and become warped. It is also one of the closest galaxies with an active galactic nucleus (AGN).
Messier 77 is also classified as a Type II Seyfert galaxy, characterized by being particularly bright at infrared wavelengths.
“At the heart of Messier 77 is a compact region filled with hot gas that handily outshines the rest of the galaxy put together, even overcoming the light-gathering capacity of Webb’s cameras,” the Webb astronomers said in a statement.
“This is an AGN, and it’s powered by M77’s central supermassive black hole, which is eight million times as massive as our Sun.”
“Gas in the galaxy’s central regions is pulled by the strong gravity into a tight and rapid orbit around the black hole, where it crashes together and heats up, releasing tremendous amounts of radiation.”
This image of Messier 77 was captured by Webb’s Near-Infrared Camera (NIRCam). Image credit: NASA / ESA / CSA / Webb / A. Leroy.
“Messier 77 is not just known for its easily visible AGN, but also as a prolific star-forming galaxy,” they added.
“The near-infrared image of Messier 77 reveals a bar spanning across the central region, which doesn’t appear in visible-light images of the galaxy.”
“The bar is enclosed by a bright ring, called a starburst ring, formed by the inner ends of Messier 77’s two spiral arms.”
“Starburst regions in galaxies are typified by extremely high star-formation rates.”
“This ring is more than 6,000 light-years across and displays intense and widespread starbursts, visible in this image by the densely concentrated orange bubbles all around the ring.”
“Since Messier 77 is relatively close to Earth, this starburst ring is a very well-studied example of the phenomenon.”
“As an active spiral galaxy, Messier 77’s disk is filled with gas and dust which is both a product of and fuel for future star formation.”
“Webb’s MIRI fills out our view of the galaxy with the glow of interstellar dust grains emitted at longer wavelengths, shown here in blue.”
“The dust forms a huge vortex of smoky, swirling filaments with cavities in between.”
“The glowing orange bubbles carved out by newly formed star clusters are also prominently visible out along the galaxy’s arms.”
“Beyond Webb’s quite focused view, Messier 77’s arms join into a faint extended ring of hydrogen gas thousands of light-years wide, where yet more star formation is taking place.”
“Vast, tenuous filaments of hydrogen gas stretch across this ring and out into intergalactic space, forming an outermost layer around the galaxy.”
“For the tentacle-like appearance of these filaments, Messier 77 is also named the Squid Galaxy.”
