Even NASA’s new-generation space observatory can’t directly observe supermassive black holes, but that doesn’t mean astronomers can’t use its data to better understand the mysterious behemoths.
The possibilities are even visible in the first science-quality images from the James Webb Space Telescope (nicknamed JWST or Webb), which NASA unveiled on July 12. While supermassive black holes themselves are invisible to all light-gathering observatories, JWST will be able to observe the structures indirectly.
Actually already there. Consider a new portrait of five galaxies that seem to be involved in a cosmic dance. “The picture of Stefan’s Quintet that we showed you is beautiful and it tells you so many things in one picture,” said John Mather of NASA’s Goddard Space Flight Center in Maryland, senior scientist at the James Webb Space Telescope. press conference held on July 19 by the Committee on Space Research (COSPAR) in connection with its annual assembly, which took place last week in Athens.
Gallery: First photos of the James Webb Space Telescope
In this image, astronomers can see a supermassive black hole, or more specifically, light emitted by heating matter and entering a massive structure that has a mass about 24 million times that of the Sun, according to the Space Telescope Science Institute in Baltimore. where the observatory operates. (The black hole is also called an active galactic nucleus because of its location at the center of the galaxy NGC 7319.)
The stunning image released by NASA combines images taken by the Near Infrared Camera (NIRCam) and the Mid Infrared Instrument (MIRI). But JWST didn’t just take photographs. Both tools also collected what scientists call data cubes, which include both images and spectral analysis, a technique that determines how much light of a given wavelength comes from a source.
The results allowed scientists to take apart the cloud surrounding the supermassive black hole and determine where many particularly interesting chemicals are located. “We are testing the environment of a black hole,” Mather said of these observations. “Now we have images of the shape of a hydrogen cloud, iron cloud, atomic hydrogen cloud, molecular hydrogen cloud as they orbit or try to get into the black hole’s gravitational field.”
(Image credit: NASA, ESA, CSA, STScI)
And, like all the observations released this month, the Stefan Quintet observations were made before the telescope began to seriously engage in scientific activity; now the JWST has embarked on what astronomers hope will turn out to be a 20-year tenure leading pioneering science.
The predecessor of the JWST, the Hubble Space Telescope, has been in operation for over 30 years and continues to operate, and this old observatory has also contributed to scientists’ understanding of supermassive black holes.
“Hubble was the first to prove without a doubt that we have black holes at the centers of galaxies, because they were able to observe the movement of stars rapidly orbiting a black hole,” Mather said.
(Image credit: NASA, ESA, CSA, STScI)
Webb will take a few more steps forward, he said. In particular, Mather hopes that the JWST observations will tell astronomers about the origin of active galactic nuclei, the supermassive black holes that lurk at the core of every galaxy. “There is a giant black hole at the center of every galaxy, and the origin of this black hole is completely unknown at the moment.”
As scientists try to unravel this mystery, they need to figure out when supermassive black holes arrived on the cosmic scene. Unlike Hubble, which sees most clearly in the visible and ultraviolet ranges of light, JWST, optimized for infrared, can reach deep enough into the history of the universe to observe a time before such structures existed.
“It’s bigger and therefore can see farther in time and farther in space, so we have more targets that we can find,” Mather said of the new observatory’s capabilities compared to Hubble’s. “We also get slightly sharper images, and since infrared radiation can penetrate dust clouds, we can see black holes much closer to the core.”
And for Mather, studying supermassive black holes is no idle pastime. He noted that the supermassive black hole at the heart of the galaxy is the dominant player in the life of everything else in the galaxy, in part because the energy released by the behemoth shapes the galaxy around it. This is no less true of our own Milky Way than it is of the distant galaxy in Stefan’s quintet.
“The history of the solar system would be very different without a black hole in our galaxy,” Mather said.
Email Meghan Bartels at mbartels@ or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.