A telescope in San Diego, California, methodically surveys the whole night sky every two nights. The Zwicky Transient Facility (ZTF) is a telescope that examines millions of stars in search of astronomical objects behaving strangely. Astronomers just spotted a record-breaking “black widow” pulsar consuming its victim.
A team of scientists reveals what seems to be a pulsar and a tiny star circling each other faster than astronomers have ever observed in an article published Wednesday in the peer-reviewed magazine Nature. However, this will not last indefinitely. This pulsar, which scientists refer to as a “black widow,” is sucking matter and energy from its unfortunate partner.
The glimmer of starlight encodes celestial secrets.
Stars are not “uninteresting, stagnant things,” according to physicist Tom Prince, a ZTF researcher and co-author of the new work. “A significant proportion of stars display dips, pulsations, or periodic brightenings that provide insight into their nature.” ZTF enables academics to examine some of these patterns in more depth than ever before.
The remarkable technique detailed in the current study was discovered after post-doctoral researcher Kevin Burdge, now at MIT, developed an algorithm that identifies objects that get significantly brighter or darker over the span of about 80 minutes. The algorithm alerted the researchers to J1406+1222, the focus of the current publication. Every 62 minutes, its brightness fluctuates by a factor of 13. The telescope cannot see it well enough to witness what is happening firsthand, but it can see well enough to alert researchers to the fact that something weird is occurring.
“This 62-minute orbit is fascinating since we have no idea how the stars achieved such a close orbit,” Burdge explains. “The mechanism by which the pulsar annihilates its companion should actually separate them. This is stretching the envelope of what we previously believed was feasible.”
The pulsar is known as the “black widow” and devours its victim.
If the researchers are correct, what they are seeing is a little companion star revolving on its axis. The effect of the black widow pulsar on the brown dwarf has resulted in one side of the smaller star being cooler than the other. When the hot side is towards Earth, the whole system looks dazzling to San Diego viewers. When it dissipates, the system becomes dull.
The two objects are not the system’s lone stars. From a considerable distance, researchers have discovered a third star orbiting the other two. The two central stars in the system circle each other for little more than an hour. The trip of the third star takes 10,000 years.
This is a plausible explanation for ZTF’s observations, but it may not represent the whole picture. “Our findings imply that we are dealing with a black widow binary, but it may be something completely else,” Burdge explains. NASA’s Chandra X-ray Observatory, a space observatory that circles the Earth in a vast elliptical, will validate the discovery.