A low-frequency radio burst from deep space has been detected by a radio telescopes in Canada, adding to the mystery of a puzzling phenomenon. The Canadian Hydrogen Intensity Mapping Experiment (CHIME) detected a rare burst of low-frequency radio waves in July, and astronomers don’t know what caused the signal. This odd occurrence could be due to black holes, collapsing stars, or even aliens.
Fast radio bursts (FRB’s) are vast releases of energy, taking place well away from the Milky Way Galaxy. First detected in 2007, these events last just a few thousandths of a second. These bursts come unexpectedly, making finding the events a rare occurrence. This burst, FRN 180725A, displayed electromagnetic radiation at a frequency of 580 megahertz (MHz) – almost 200 MHz lower than the previous record. This first confirmed low-frequency burst was only first detected on July 25, 2018, but it has already been joined by other similar events.
“Additional FRBs have been found since FRB 180725A and some have flux at frequencies as low as 400 MHz. These events have occurred during both the day and night and their arrival times are not correlated with known on-site activities or other known sources of terrestrial RFI [radio frequency interference],” Patrick Boyle of McGill University reported in The Astronomer’s Telegram.
Rainbows of light contain far more “colors,” or frequencies than what we see with the naked eye. At longer wavelengths than red sit infrared, microwave, and radio waves. At the other end of the spectrum, beyond blue and violet, lie ultraviolet, X-ray, and gamma rays. The ultra-low frequency and the magnitude of the burst suggests the event responsible for the FRB was immensely powerful, although they were located far from Earth.
There are several explanations which could explain these mysterious FRB’s, including massive stars collapsing in on themselves as they perish, black holes, or the ultra-dense stellar corpse – neutron stars. One possible explanation for these FRB’s is a neutron star trapped in a gravitational embrace with a black hole.
An intelligent alien source for these displays cannot yet be ruled out, however. Since the first FRB was recorded in 2007, fewer than 50 of the events have been seen by astronomers. However, only one – FRB 121102 – repeats the display.
The radio telescope at the Canadian Hydrogen Intensity Mapping Experiment is a unique observatory, having no moving parts. The radio telescope is capable of observing approximately 200 degrees of arc in the sky at one time – more than 30 percent more than is visible with the human eye. This quality makes the instrument ideal for discovering new FRB’s.