Saturday, February 26, 2000

2/26/00 12:49:04 PM

• Too quiet, White Man. The X-ray source Cygnux X-3 is about to blow. Last Thursday its radio emissions dropped dramatically and have stayed low; its hard-X-ray emissions have been minimal for the last month. The last time Cyg X-3 went nearly silent in both radio and hard X-ray, in 1997, a massive eruption followed.

  Cyg X-3 is believed to be a binary system within our own galaxy consisting of a neutron star or black hole orbiting a Wolf-Rayet star. The latter is a class of stars 7 to 50 times as massive as our sun that have blown off their outer layer of hydrogen; the resulting helium star features a vigorous stellar wind. All the electromagnetic activity happens in the accretion disk surrounding the collapsed junior partner of the binary system. During a major outburst, Cyg X-3 shoots X-ray jets in opposite directions from the poles of the accretion disk. We happen to be positioned looking right down the barrel of one of those polar jets.

  When Cyg X-3 blows this time, mankind will be ready and watching. NASA scientist Mike McCullough has been granted "target of opportunity" time to observe Cyg X-3 with the Chandra X-ray Observatory, the Compton Gamma Ray Observatory, and the Rossi X-ray Timing Explorer. McCollough and colleagues are now monitoring Cyg X-3 using instruments in West Virginia, Britain, Russia, and New Mexico. When the flare begins these instruments will be joined by the Very Long Baseline Array, which is effectively a radiotelescope as big as the earth.

Sunday, February 20, 2000

2/20/00 2:33:50 PM

• A spam magnet. TBTF Irregular Steve Yost came across this clever use of Hypermail while browsing one of his sites' referrer logs. An outfit called Tinaa has set up a spam attractor. Here's the idea: when you sign up for some service on the Web that requires an email address, and you suspect that providing one might subject you to spam, use the address spam@tinaa.com instead. Then visit Tinaa's mail page from time to time to see what spam you've harvested.