A brand new telescope is coming online, but it doesn't look all that new to most.
The Expanded Very Large Array, or EVLA, uses the same Y-shaped array of radio dishes that fans of "Contact" are familiar with, but its new equipment and capabilities seem to open it up to a new universe of objects to explore. Take for example, this image of a galaxy with a recent supernova which is contributing to scientific progress during commissioning.
The image is of a galaxy 100 million light years away, NGC 2967. Even at that great distance, the EVLA can resolve structure in the radio emission. Because it is made of several (27, in fact) telescopes spread across the plains of San Augustine in New Mexico, it acts as one large telescope, achieving very fine spatial resolution.
Resolution is on the order of a few arcseconds, where an arcsecond is 1/3600th the width of your finger at arms length, or reading a letter an inch high from 3 miles away.
In July, this galaxy had a supernova go off called a Type 1a supernova. This means that a white dwarf, or an extremely dense and hot, but small star, had too much gas dumped on to it be a neighbor, and it underwent a violent explosion.
SLIDE SHOW: Using a powerful supercomputer to visualize the inner workings of a Type Ia supernova.
However, it is not clear which supernovae come from a single white dwarf event or a binary white dwarf. Each kind has its own pattern of changing brightness in the first few weeks after the initial explosion Astronomers caught this one just 10 days after the initial burst, and the same day that it was optically identified.
The colors in the image indicate brightness. Radio astronomers are free to color their plots however they like since we don't see radio light with our eyes. Red is the brightest and the supernova itself is the red dot just to the left of the main galaxy emission.
The new and improved sensitivity of the EVLA will make detecting these supernovae -- and many more astrophysically interesting phenomena -- possible in ways that has not been done before.
It seems that you can teach an old telescope new tricks!
Image: Images of NGC 2967 at 5 GHz taken with the EVLA. The one on the right is in a more sensitive, but currently still more experimental mode. Credit: NRAO/AUI (Chomiuk, Soderberg, Chevalier, Badenes, and Fransson.)
Thanks @privong for tweeting about it!
Tags: Astrophysics, Supernova, Telescopes
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