People commonly expect that astronomy is done by a lonely astronomer peering through a telescope all night long. That idea has been wrong for more than 100 years.
Earlier this week astronomers from the Palomar Transient Factory announced the discovery of another supernova. The discovery was announced electronically via the Astronomer's Telegram, specifically #2470. The text is written for astronomers and may not be too digestible to the general public, but it and the follow-up announcement give a glimpse on how modern astronomers work to understand the universe.
I have talked about it before, but the Palomar Transient Factory uses the wide-angle 48-inch Samuel Oschin Telescope to first survey the sky. The telescope is robotically operated. Data collected from the 96-megapixel camera is beamed away via the High-Performance Wireless Research and Education Network (HPWREN) to a computing center at Berkeley where they are compared to previous images taken of the same location in the sky. In the recent case they found a faint (from our distant vantage on Earth) new supernova (named PTF 10bzf) located in an distant unnamed galaxy the night of February 23. The same portion of the sky had been previously surveyed four nights earlier and the supernova was not there. This means that the supernova was only four days old, or possibly even younger, giving astronomers a chance to catch key details of the stellar explosion as they unfold.
Typically, there is an early set of follow-up observations with the Palomar 60-inch telescope to obtain brightness and color information and then other telescopes are called into play to obtain a spectrum. To the astronomer a spectrum is essentially DNA evidence that provides key evidence toward understanding of an object or event. The Gemini North telescope on the Big Island of Hawai'i was able to provide the first spectrum of the supernova, allowing astronomers to classify this outburst as a "broad-line Type Ic supernova".
Type Ic supernovae are thought to be produced by the collapse of massive stars that have had their outer layers stripped away. Some of these events may also give rise to gamma-ray bursts.
To study the supernova further astronomers began a multi-wavelength follow-up campaign. Just as a doctor may use a variety of instruments to diagnose a person's ailment, astronomers use a wide variety of telescopes, that peer into different parts of the electromagnetic spectrum, to diagnose and understand the mechanics of what happens as a star explodes.
The first reports of those observations are just starting to roll in.
Telegram #2471 reports observations from NASA's Swift satellite which can detect gamma-rays and X-rays. These are types of light that are very short in wavelength and very high in energy. Because these types of light are absorbed by Earth's atmosphere satellites, like Swift are essential in letting astronomers probe
The next report of observations, telegram #2473, came from the Combined Array for Research in Millimeter-wave Astronomy (CARMA) facility located in Cedar Flat, CA. CARMA looks at light that is longer in wavelength than visible (or even infrared) light, but shorter than what most people call radio waves.
Other telescopes have likely already been called into action. Observations will continue across many wavelengths of light, possibly for months to come as the supernova evolves. The analysis of the details of this supernova explosion will also take many months as astronomers work to piece together the story of how and why this star died.
Excellent...thank you
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