http://www.newsweek.com/mystery-radio-signals-ross-128-star-637682
Scientists have discovered mystery signals coming from a star 11 light-years away. The “very peculiar” pulses appear to be unique to the red dwarf, scientists say, with observations of similar nearby stars showing no similar behavior.
Researchers at the Arecibo Observatory, in Puerto Rico, were observing a group of red dwarf stars in a bid to identify planets and other objects orbiting them. In April and May, the team recorded information coming from Gliese 436, Ross 128, Wolf 359, HD 95735, BD +202465, V* RY Sex and K2-18.
After analyzing the data, they noticed something odd: Ross 128 had been emitting strange radio signals. In a blog post, Abel Méndez, director of the Planetary Habitability Laboratory at the University of Puerto Rico at Arecibo, said the origin of the radio signals is not known.
more here:
http://phl.upr.edu/library/notes/ross128
Two weeks after these observations, we realized that there were some very peculiar signals in the 10-minute dynamic spectrum that we obtained from Ross 128 (GJ 447), observed May 12 at 8:53 PM AST (2017/05/13 00:53:55 UTC). The signals consisted of broadband quasi-periodic non-polarized pulses with very strong dispersion-like features. We believe that the signals are not local radio frequency interferences (RFI) since they are unique to Ross 128 and observations of other stars immediately before and after did not show anything similar.
We do not know the origin of these signals but there are three main possible explanations: they could be (1) emissions from Ross 128 similar to Type II solar flares, (2) emissions from another object in the field of view of Ross 128, or just (3) burst from a high orbit satellite since low orbit satellites are quick to move out of the field of view. The signals are probably too dim for other radio telescopes in the world and FAST is currently under calibration.
Each of the possible explanations has their own problems. For example, Type II solar flares occur at much lower frequencies and the dispersion suggests a much farther source or a dense electron field (e.g. the stellar atmosphere?). Also, there are no many nearby objects in the field of view of Ross 128 and we have never seen satellites emit bursts like that, which were common in our other star observations. In case you are wondering, the recurrent aliens hypothesis is at the bottom of many other better explanations.
Therefore, we have a mystery here and the three main explanations are as good as any at this moment. Fortunately, we obtained more time to observe Ross 128 next Sunday, July 16, and we might clarify soon the nature of its radio emissions, but there are no guarantees. We will also observe Barnard’s star that day to collaborate with the Red Dots project. Results from our observations will be presented later that week.