What would nights be like if Earth were located in the galaxy Messier 77? Say it’s not too far from the galaxy’s nucleus; close enough to see the fireworks.
As we gaze toward the galactic center, the way we look to the beautiful star clouds of Sagittarius low in the south on a clear summer night, an incredible scene presents itself. A monstrous, thick, glowing structure reaches outwards, a vast tunnel of energy that changes in brightness within days. It’s a tornado of hot plasma with brighter swirls and blobs creeping along it, moving out from the base.
At least, that’s how I imagine it might look, based on observations by radio telescopes and two great NASA orbiting facilities, the Hubble Space Telescope and the Chandra X-Ray Observatory.
Here’s how I actually saw M77, based on more than three hours’ work with my telescope and camera, set up in Jerry and Cindy Foote’s driveway a few miles outside Kanab.
[Galaxy M77, taken through my Meade 12-inch-diameter telescope, night of Oct. 29-30, near Kanab. Photo by Joe Bauman]
M77, also known as NGC1068, is one of the closest examples of a Seyfert galaxy, that is, the type that possesses an active galactic nucleus. It’s near enough — an estimated 50 million light-years away — to serve as a convenient target for many studies.
The galaxy is in the constellation Cetus, the sea monster, which is floating high just now. The active nucleus is a source of intense X-rays and radio rays, both generated by the supermassive black hole in the middle of the galaxy. The bright spiral shape at the center is surrounded by much dimmer, fluffy-looking extensions of the arms.
In 2006, NASA estimated the galaxy is 60 million light-years away, which would make its disk more than 100,000 light-years across, bigger than the Milky Way. Last year the agency said M77 is 50 million light-years away, which would make the diameter somewhat smaller than the earlier estimate.
The black hole’s size seems hard to pin down, since StarDate, maintained by the University of Texas McDonald Observatory, claims it is “about 15 million times the mass of our Sun” while the National Radio Laboratory estimated in 2000 that it is “about 10 million times more massive than the Sun.” It may be twice as large as the black hole at the center of our Milky Way Galaxy but it’s far more active, devouring gigantic amounts of matter.
The black hole is pulling in material from shredded stars and other victims. As the gas swirls around the drain at 1 million miles an hour, much is sucked into the hole, vanishing, drawn to a single point of incomprehensible density and mass.
But outside the black hole, the speed of the whirling gas is so great that this torus heats up to 180,000 degrees F., magnetic lines of force form, and some of the material shoots away from the center in a gigantic jet, according to the Chandra site operated by the Smithsonian’s Astrophysical Observatory in Cambridge, MA.
A Chandra study shows that each year, “several times the mass of our sun is being deposited out to large distances, about 3,000 light-years from the black hole,” reads a Chandra press release dated March 3, 2010. “The wind likely carries enough energy to heat the surrounding gas and suppress extra star formation.”
[The box drawn in the middle of this photo of M77 by the Palomar Digital Sky Survey shows the location of the following view. The box is about 7,000 light-years across. Credit: Pal.Obs. DSS]
[This view of M77 would fill the square above. It is a composite of X-ray imaging by Chandra, radio signals gathered by the Very Large Array of radio telescopes in New Mexico, and false-color optical photos by Hubble. Credit: X-ray (NASA/CXC/ MIT/C.Canizares, D.Evans et al), Optical (NASA/STScI), Radio (NSF/ NRAO/VLA]
I’m grateful to live in a time when we can begin to comprehend the terrible beauty of the universe.