Astronomy

A rare astronomical sight is unfolding in the southern sky. Two exploding stars are shining so brightly that both can be viewed with the naked eye.

It’s hard to predict how long these “fascinating objects” will remain that radiant, but stargazers may have another four to five nights to witness the dual phenomena, says astronomer Juan Luna of the Universidad Nacional de Hurlingham in Buenos Aires.

These stellar bursts are considered novas. Unlike star-killing supernovas, the dimmer blasts only affect a star’s outer region. A nova occurs when a dense white dwarf star pulls material from its companion star, which are stuck together in a binary system. The stolen gas accumulates, heating up and building pressure until it explodes and suddenly lights up the sky.

One of the current novas was first spotted on June 12. Named V462 Lupi, it’s located within the Lupus constellation best seen from the Southern Hemisphere, though some people have reported seeing it from the United States. The eruption reached peak brightness on June 20, and now it’s slowly dimming, Luna says.

In contrast, the second nova, called V572 Velorum, seems to be changing intensity very quickly, he says. It was detected on June 25, reached peak brightness two days later and is in the southern constellation Vela.