New Brightest Supernova!
University of California has discovered the brightest
supernova. Name is SN2014J. It is an brightest and faster Ia type supernova.
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A colour composite of SN 2014J, located in the "cigar
galaxy" M82, 11.4 million light years away, made from KAIT images obtained
through several different filters. The supernova is marked with an arrow. Other
round objects are relatively nearby stars in our own Milky Way Galaxy. Image by
W. Zheng and A. Filippenko, UC Berkeley.
When University of California, Berkeley, astronomer Alex
Filippenko's research team looked for the supernova in data collected by the
Katzman Automatic Imaging Telescope (KAIT) at Lick Observatory near San Jose,
Calif., they discovered that the robotic telescope had actually taken a photo
of it 37 hours after it appeared, unnoticed, on Jan. 14.
New telescopes to catch more supernovae
Because of the importance of supernovae in measuring the
universe, many new telescopes, such as the Palomar Transient Factor in San
Diego County and the Pan-STARRS in Hawaii, continually rescan the sky to
discover more of them. The KAIT telescope has a smaller field of view than
newer ones do, so Filippenko's team has switched its focus to discovering
supernovae earlier: it scans the same patches of sky every night or every other
night. The sooner a new explosion is discovered, the sooner astronomers can
capture information, such as spectra showing how the supernova brightens in
different colors or wavelengths.
Last year, for example, KAIT and Filippenko's Lick
Observatory Supernova Search (LOSS) team discovered and photographed SN 2013dy
within two and a half hours of its appearance, earlier than for any other Type
Ia. KAIT, which is operated by postdoctoral scholar WeiKang Zheng, is
programmed to automatically take images of likely supernovae in five different
wavelength bands, and in 2012 captured one supernova, SN 2012cg, three minutes
after its discovery.
"Very, very early observations give us the most
stringent constraints on what the star's behavior really is in the first stages
of the explosion, rather than just relying on theoretical speculation or
extrapolating back from observations at later times, which is like observing
adolescents to understand early childhood," Filippenko said.
Filippenko's colleagues include Zheng; UC Berkeley graduate
student Isaac Shivvers; assistant specialist Kelsey I. Clubb; postdoctoral
scholars Ori D. Fox, Melissa L. Graham, Patrick L. Kelly and Jon C. Mauerhan;
and amateur astronomer Koichi Itagaki of the Itagaki Astronomical Observatory
in Yamagata, Japan, who captured an image of SN 2014J just 20 hours after it
exploded.
The research was funded by the TABASGO Foundation, the
Sylvia & Jim Katzman Foundation, the Christopher R. Redlich Fund, Gary and
Cynthia Bengier, the Richard and Rhoda Goldman Fund, Weldon and Ruth Wood, and
the National Science Foundation.
Summary: The closest and brightest supernova in decades, SN
2014J, brightens faster than expected for Type Ia supernovae, the exploding
stars used to measure cosmic distances, according to astronomers. Another
recent supernova also brightened faster than expected, suggesting that there is
unsuspected new physics going on inside these exploding stars. The finding may
also help physicists improve their use of these supernovae to measure cosmic
distance.
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