NASA’s SOFIA mission is upgraded and back in action, and the Cigar Galaxy makes a perfect target.
In theory, cold, neutral gas is the key to stars and galaxies.
A visualization of gas falling into a young galaxy shows what it might appear to look like, if the gas (rather than the stars) were visible to the naked eye. Note that this gas is a required ingredient for star formation; when gas collapses, new stars are born, but without this gas, no new stars can form. (R. CRAIN (LJMU) AND J. GEACH (U. HERTS))
When gas clouds gravitationally collapse, new stars can form.
A cloud of gas collapses, forming new stars, while radiation works to evaporate it. The evaporative ultraviolet radiation comes from two sources: the proto-stars forming inside, and the radiation of young stars from outside of it. When the cloud, known as a frEGG (free-floating evaporating gaseous globule) evaporates, a mix of true stars and “failed” stars will be left behind. (ESA/HUBBLE & NASA, R. SAHAI)
One the gas is completely gone, however, star formation ceases.
A map of neutral hydrogen (in red) overlaid on this galaxy in the Coma Cluster shows how much gas is being quickly stripped from this galaxy as it travels through the cluster. Galaxies found in environments like this one become ‘red and dead’ far more quickly than galaxies in less dense regions of space. Note the redder elliptical galaxies towards the left; they have been devoid of gas for billions of years already. (NASA, ESA, AND W. CRAMER AND J. KENNEY (YALE UNIVERSITY))
Paradoxically, the largest starbursts can ruin a galaxy’s future star-forming potential.
Combined observations from Chandra (purple), the Very Large Array (yellow) along with Hubble (red, green, and blue) have provided astronomers with a detailed new look at how galaxy and black hole formation may have occurred in the early Universe. Galaxy bulges and supermassive black holes grow in tandem in the modern Universe, but this galaxy appears to be an outlier. (X-RAY (NASA/CXC/VIRGINIA/A.REINES ET AL); RADIO (NRAO/AUI/NSF); OPTICAL (NASA/STSCI))
Starburst galaxies are rare, occurring when the entire galaxy becomes a star-forming region.
The Cigar Galaxy, M82, and its supergalactic winds (in red) that showcase the rapid new star formation occurring within it. This is the closest massive galaxy undergoing rapid star formation like this to us, and its winds are so powerful that nearly all of the heavy elements produced by the deaths of these stars would be permanently ejected without dark matter to keep it gravitationally bound. (NASA, ESA, THE HUBBLE HERITAGE TEAM, (STSCI / AURA); ACKNOWLEDGEMENT: M. MOUNTAIN (STSCI), P. PUXLEY (NSF), J. GALLAGHER (U. WISCONSIN))
The closest one is
the Cigar Galaxy (Messier 82), merely 12 million light-years away.
Located just outside the Big Dipper, the objects M81 and M82 have often been used as an analogy for Andromeda and the Milky Way. While Andromeda still has more stars, it’s possible that the Milky Way is nearly as large and luminous. M81 and M82, the Cigar Galaxy, are gravitationally interacting, with new stars and great galactic winds arising in M82. (MARKUS SCHOPFER / C.C.-BY-2.5)
larger neighbor’s gravitational influence is triggering this starburst.
NASA’s SOFIA telescope, which flies on board a modified Boeing 747, is uniquely suited to making high-quality, high-altitude far-infrared observations while still having serviceable, upgradable instruments on board. (ECHO ROMEO / PHYSICS CENTRAL / AMERICAN PHYSICAL SOCIETY)
In 2019, NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA)
studied the Cigar Galaxy’s gas with unprecedented sensitivities.
NASA’s Stratospheric Observatory for Infrared Astronomy, SOFIA, has an enormous advantage over space telescopes: it’s easily serviceable and upgradeable. New instruments, like High-resolution Airborne Wideband Camera-Plus (HAWC+) shown here or the newly-added German REceiver for Astronomy at Terahertz Frequencies (GREAT) instrument, enable observations that perhaps couldn’t have been even envisioned when SOFIA was first designed. (NASA)
SOFIA observes at 41,000+ feet,
avoiding 99% of atmospheric water vapor: infrared astronomy’s biggest nemesis.
The transmittance or opacity of the electromagnetic spectrum through the atmosphere. Note all the absorption features in gamma rays, X-rays, and the infrared, which is why the greatest of our observatories in these wavelength are all located in space. The infrared, in particular, suffers from water vapor in the atmosphere, but extremely high altitude observations are possible there, not merely space-based. (NASA)
its enormous galactic wind is aligned along internal magnetic field lines.
This composite image shows the magnetic field detected by SOFIA (streamlines), where the outflows of gas, shown in red, appear to point along the same direction as the magnetic field lines. At just 12 million light-years away, this galaxy, Messier 82, is our closest laboratory for studying starburst galaxies. (NASA/SOFIA/E. LOPEZ-RODRIGUEZ; NASA/SPITZER/J. MOUSTAKAS ET AL.)
Enormous quantities of gas and dust — upwards of 50,000,000 Suns — is being transported into intergalactic space, dragging the field with it.
This infrared image from NASA’s Spitzer Space Telescope shows the Cigar Galaxy in two different wavelengths, where the shorter-wavelength (blue) light traces the galaxy’s hot stars, while the longer-wavelength (red) light traces the galaxy’s dust particles, which are being blown out into intergalactic space. (NASA/JPL-CALTECH/UNIVERSITY OF ARIZONA)
This episode of copious star formation may deplete the Cigar Galaxy entirely.
Post-merger, large spirals will result in the formation of a single, giant elliptical galaxy. Over time, the stars inside will become redder as the blue ones die the fastest. The galaxies M81 and M82 will merge together eventually, but M82 may run out of gas even before that due to the ongoing starburst triggered by M82. (NASA, ESA, AND THE HUBBLE HERITAGE TEAM (STSCI/AURA))
Novel science continues, even during this pandemic, with international cooperation.
In February and March of 2021, NASA’s SOFIA will conduct science flights over Germany for the first time. The German Aerospace Center, DLR, has been a joint partner with NASA on SOFIA for over 25 years, and science teams in Bonn and Cologne are eager to take advantage of this new opportunity. (ALEXANDER GOLZ)
New SOFIA observations are
being conducted over Germany, investigating ionized carbon: a key tracer of star formation.
The unusual hot massive young star WR 22 is silhouetted against a portion of the Carina nebula here, and exhibits signs of highly, multiply ionized heavy elements like carbon and nitrogen. Observations of ionized carbon can help astronomers identify the warmest dust regions, which are heated by nearby newborn, massive stars. (ESO)
Combined observations of star birth, winds, and matter transport will reveal key relationships underlying galaxy evolution.
An enormous star-forming region in the dwarf galaxy UGCA 281, as imaged by Hubble in the visible and the ultraviolet, as part of the LEGUS survey. The blue light is starlight from hot, young stars reflected off of the background, neutral gas, while the brightest patches indicate the greatest emission of UV light. The red portions, however, are evidence of ionized hydrogen gas, which emits a characteristic red glow as electrons combine with the free protons. The gas is being expelled from this region due to stellar winds from the hottest young stars. (NASA, ESA AND THE LEGUS TEAM)
Mostly Mute Monday tells an astronomical story in images, visuals, and no more than 200 words. Talk less; smile more.
Starts With A Bang is written by Ethan Siegel , Ph.D., author of Beyond The Galaxy , and Treknology: The Science of Star Trek from Tricorders to Warp Drive .