Astronomers have found what may be the first exoplanet in another galaxy ever detected

This looks exciting here for possibly finding a exoplanet in M51 (a very good target for telescope users). I note in the report, "However, the object won't transit in front of its star again for 70 years, so it will be a long time before scientists are able to make this observation again. "Unfortunately to confirm that we're seeing a planet we would likely have to wait decades to see another transit," co-author Nia Imara, a researcher at the University of California at Santa Cruz, added in the same statement. "And because of the uncertainties about how long it takes to orbit, we wouldn't know exactly when to look." It is possible, but highly unlikely, the researchers acknowledge in the statement, that the dimming could be caused by something like a cloud passing in front of the star."

Confirmation looks tough. Here is another report on this possible exoplanet some 28 million light years distance. Astronomers may have discovered the first planet outside of our galaxy (

"...The team used this method to detect the exoplanet candidate in a binary system called M51-ULS-1, located in M51. This binary system contains a black hole or neutron star orbiting a companion star with a mass about 20 times that of the Sun. The X-ray transit they found using Chandra data lasted about three hours, during which the X-ray emission decreased to zero. Based on this and other information, the researchers estimate the exoplanet candidate in M51-ULS-1 would be roughly the size of Saturn, and orbit the neutron star or black hole at about twice the distance of Saturn from the Sun. While this is a tantalizing study, more data would be needed to verify the interpretation as an extragalactic exoplanet. One challenge is that the planet candidate's large orbit means it would not cross in front of its binary partner again for about 70 years, thwarting any attempts for a confirming observation for decades."

Difficult and tough confirmation awaits here. Using 20 au for the distance for this possible exoplanet from the neutron star or BH and a distance of 8.58 x 10^6 pc, a telescope operating near 1 arcsecond angular resolution would be about 8.58 x 10^6 au diameter resolution. A long way from seeing 20 au across at that distance :)

Another new exoplanet report is 2M0437 b.
Reference paper cited, Zodiacal Exoplanets in Time (ZEIT) XII: A Directly-Imaged Planetary-Mass Companion to a Young Taurus M Dwarf Star,, 16-Oct-2021.

Jaw-Dropping Direct Image Shows a Baby Exoplanet Over 400 Light-Years Away,, 24-Oct-2021.

It is easier to verify exoplanets like this report for 2M0437 b when you compare with the possible exoplanet report in M51. M51-ULS-1 looks to be very difficult to confirm.
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