This spring, astronomers at the Arecibo Observatory in Puerto Rico were sorting through data from recent observations when they found something strange. The radio telescope had detected what they describe as “some very peculiar signals” coming from a nearby star, unlike anything they had ever observed before.
The star in question is Ross 128, a red dwarf located about 11 light-years from Earth in the constellation Virgo. Red dwarfs are the smallest and most common types of stars in the universe. They’re far dimmer than stars like our sun, and can’t be seen with the naked eye. For about 10 minutes on May 12, a radio transmission came from the direction of Ross 128. Stars can emit various wavelengths of electromagnetic radiation, including radio waves. But the pulses that came from Ross 128 were at a frequency astronomers haven’t detected before in red dwarfs.
The Arecibo astronomers reported the mystery detection in a online post last week, but they don’t yet know its origins.
There are several possible explanations, all of which have some limitations. Scientists have known for decades that red dwarfs can emit flares, intense eruptions of electromagnetic radiation, like the kind that occur on our own sun. But the flares that have been observed on red dwarfs occur at much lower frequencies and travel in different directions than what was seen around Ross 128. If the cause is indeed a solar flare, it would be a new classification of flares astronomers have never observed before.
The radio signals could be coming from another object in the telescope’s field of view of Ross 128, but astronomers haven’t observed many other celestial bodies there.
They could have been emitted by a passing satellite, a common occurrence in stellar observations. But the astronomers say they have never …read more
Source:: The Atlantic – Science