The globular cluster M92 in Hercules is a well-recognized goal for beginner astronomers, a compact swarm of stars close to M13, one of many brightest globulars seen from the northern hemisphere. M92 can be one of many oldest recognized globulars within the Milky Way, made up of stars between 12 billion and 13 billion years previous.
Astronomers utilizing the James Webb House Telescope imaged M92 final summer time as a part of an ongoing examine of stellar evolution. The traditional cluster was additionally focused to assist calibrate Webb’s science devices utilizing a area of comparatively close-packed, resolved stars.
“We … selected M92 as a result of it is extremely dense,” stated Rutgers College researcher Roger Cohen. “There are numerous stars packed collectively very carefully. Taking a look at M92 permits us to check how Webb performs on this specific regime, the place we have to make measurements of stars which might be very shut collectively.”
Whereas M92 has been extensively studied with the Hubble House Telescope and different ground- and space-based devices, Webb operates at infrared wavelengths and is ideally fitted to finding out cool, low-mass stars.
“We have been really in a position to attain right down to the bottom mass stars, stars lower than 0.1 occasions the mass of the sun,” stated Cohen. “That is very near the boundary the place stars cease being stars. … These observations weren’t really designed to push very exhausting on the boundaries of the telescope. So it’s very encouraging to see that we have been nonetheless in a position to detect such small, faint stars with out attempting actually, actually exhausting.”
