Dude, ofc they couldn’t observe the black hole itself, that’s the speed of the disc around it.
As for the rotation, even the article states 15 days. The impressive part is (with approximations) figuring out the speed of the disc (you can’t just zoom in on a billon light years & measure distances).
15 days. Great. What’s the circumference? Oh, they didn’t give that either. “15 days” is still not a rotational velocity, it’s linear.
I’m not giving these folks grief for doing near impossible measurements, I’m giving the article grief for claiming a measurement was made, and then not stating said measurement.
Dude, ofc they couldn’t observe the black hole itself, that’s the speed of the disc around it.
As for the rotation, even the article states 15 days. The impressive part is (with approximations) figuring out the speed of the disc (you can’t just zoom in on a billon light years & measure distances).
15 days. Great. What’s the circumference? Oh, they didn’t give that either. “15 days” is still not a rotational velocity, it’s linear.
I’m not giving these folks grief for doing near impossible measurements, I’m giving the article grief for claiming a measurement was made, and then not stating said measurement.