Two invisible stars are bending space-time deep in the Milky Way

The stars are turning the space between them into a field of cosmic magnifying glasses, and that’s screwing with our view of a star much farther away.

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Tau.Neutrino said:

Two invisible stars are bending space-time deep in the Milky Way

The stars are turning the space between them into a field of cosmic magnifying glasses, and that’s screwing with our view of a star much farther away.

more…

> In summer 2016, astronomers watched a star 2,500 light-years away in the Cygnus constellation flash to life as if preparing to explode in a fiery supernova. The next day, however, the star dimmed back to normal again — no fuss, no kaboom. Within a few weeks, the strange cycle repeated itself: The star suddenly brightened, then dimmed again within a day. Over the following year, the cycle occurred again and again, repeating five times within 500 days.

Got another explanation? I can’t think of one off-hand, but it’s very unusual for star velocities relative to one another to be so small that you get more than one or two gravitational microlensing events.

Let me try a few numbers. The relative speed of stars in the Milky Way is close to 20 km/s. That’s local variation, over larger distances such as this, relative speeds could be much larger. 20 km/s over the 500 days is about 850 million km. The diameter of a red dwarf is, by comparison 200,000 km. For a red dwarf in a binary system to cause a microlensing event the centre would have to pass within about 10% of the radius of the direct line of sight, about 10,000 km. Which is a heck of a lot less than 850 million km.

Which looks like a probability approaching one part in 85,000 of this being possible. That’s only a ballpark order of magnitude and more complete data would change that, but a more likely explanation is needed. (eg. running lights from an alien spacecraft).