You are here

The Scorpion’s Tail

July 21, 2012

The celestial scorpion packs a mighty sting — the two stars that mark its “stinger” are quite impressive.

Scorpius is low in the south at nightfall, with its brightest star, orange Antares, near its middle. The tail curls to the lower left of Antares, forming a hook with the barbed stinger at the end.

The brighter of the stinger stars is Lambda Scorpii. It’s actually a system of three stars. Two of them are hot giants that are thousands of times brighter than the Sun. They’re also much more massive than the Sun. In fact, one of them may be massive enough to end with a titanic explosion — a supernova. Either way, both stars are nearing the ends of their “normal” lifetimes and soon will enter their final phases.

Lambda Scorpii’s third star may be on the other end of the age scale — an infant that hasn’t yet settled into stellar maturity. If so, it’ll outlive its siblings by millions or billions of years.

Upsilon Scorpii forms the stinger’s tip. It’s more than 500 light-years away — half again as far as Lambda. Yet indications are that it’s a single star, which makes it impressive indeed — about 12,000 times brighter than the Sun. It’s a similar mass to the two older stars of Lambda. But it appears to be a little bigger, which is why it shines so brightly. It, too, may end its life as a supernova — adding a little more zing to the scorpion’s sting.

We’ll talk about some stars that are close to the stinger tomorrow.


Script by Damond Benningfield, Copyright 2012


Get Premium Audio

Listen to today's episode of StarDate on the web the same day it airs in high-quality streaming audio without any extra ads or announcements. Choose a $8 one-month pass, or listen every day for a year for just $30.