Two amateur astronomers based in Florida yesterday helped set in motion a global network of ground- and space-based telescopes to point to a violent explosion of one of our Galaxy's distant stellar inhabitants.

The object, U Scorpii, is a recurrent nova that was predicted to outburst during a two-year window beginning in spring 2008. Amateur astronomers Barbara Harris of New Smyrna Beach, Florida and Shawn Dvorak of Clermont, Florida were active participants in the global research campaign run by the American Association of Variable Star Observers (AAVSO) to monitor the star, and their detection of activity early on the 28 Janaury meant that professional telescopes and space-based telescopes could quickly slew to that location to monitor the outburst.

Harris reported the first detection just before 6am local time, with Dvorak's independent observation confirming the event shortly after. Within an hour the campaign's organiser Bradley Schaefer of Louisiana State University set in motion the global network of observatories, which included the Rossi X-Ray Timing Observatory and the INTEGRAL satellite.

“This again shows the real advantage of the worldwide distribution of amateur astronomers for detecting transient events like this,” says AAVSO Director Arne Henden. “Harris and Dvorak could watch U Sco rise over the Atlantic, hours before professional astronomers in the Western U.S. would have a chance. Then, because of the winter weather for most U.S. professional observatories, amateurs continued monitoring U Sco from New Zealand and Australia, catching the important first hours of the outburst.”

A subsequent set of time-series images by Dvorak suggests that U Scorpii was caught at or near maximum, prior to its expected rapid decline.

Schaefer had been coordinating both professional and amateur observers from around the globe, monitoring U Sco every night during the last years. They will continue to monitor the outburst over the coming months, in wavelengths from radio to X-rays.

“Amateurs have the option of observing what they want, when they want,” comments AAVSO’s Observing Campaign coordinator Matthew Templeton. “Sometimes, the only source of observational data for projects such as this is the amateur community. The observers of the AAVSO have been working with the professional community for decades to provide this kind of help. It’s a key part of the process of doing scientific research, and the work of the amateur community makes it possible.”

The progress of the U Scorpii outburst can be followed online at http://www.aavso.org/news/usco.shtml where anyone can view observational data as they are submitted in real time through the AAVSO website.