"The surface of the Earth is the shore of the cosmic ocean... Recently, we've managed to wade a little way out, and the water seems inviting." - Carl Sagan
Spitzer stares into the heart of new supernova in M82
The closest supernova of its kind to be observed in the last few decades has sparked a global observing campaign involving legions of instruments on the ground and in space, including NASA’s Spitzer Space Telescope. With its dust-piercing infrared vision, Spitzer brings an important perspective to this effort by peering directly into the heart of the aftermath of the stellar explosion.
Dust in the supernova’s host galaxy M82, also called the “Cigar galaxy,” partially obscures observations in optical and high-energy forms of light. Spitzer can, therefore, complement all the other observatories taking part in painting a complete portrait of a once-in-a-generation supernova, which was first spotted in M82 on Jan. 21, 2014. A supernova is a tremendous explosion that marks the end of life for some stars.
"At this point in the supernova’s evolution, observations in infrared let us look the deepest into the event," said Mansi Kasliwal, Hubble Fellow and Carnegie-Princeton Fellow at the Observatories of the Carnegie Institution for Science and the principal investigator for the Spitzer observations. "Spitzer is really good for bypassing the dust and nailing down what’s going on in and around the star system that spawned this supernova."
Supernovas are among the most powerful events in the universe, releasing so much energy that a single outburst can outshine an entire galaxy. The new supernova, dubbed SN 2014J, is of a particular kind known as a Type Ia. This type of supernova results in the complete destruction of a white dwarf star-the small, dense, aged remnant of a typical star like our sun. Two scenarios are theorized to give rise to Type Ia supernovas. First, in a binary star system, a white dwarf gravitationally pulls in matter from its companion star, accruing mass until the white dwarf crosses a critical threshold and blows up. In the second, two white dwarfs in a binary system spiral inward toward each other and eventually collide explosively.
Type Ia supernovas serve a critically important role in gauging the expansion of the universe because they explode with almost exactly the same amount of energy, shining with a near-uniform peak brightness. The fainter a Type Ia supernova looks from our vantage point, the farther away it must be. Accordingly, Type Ia supernovas are referred to as “standard candles,” which allow astronomers to pin down the distances to nearby galaxies. Studying SN 2014J will help with understanding the processes behind Type Ia detonations to further refine theoretical models.
Image credit: NASA/JPL-Caltech/Carnegie Institution for Science