Comment by sounds | Hacker News Reader

Comment by sounds | Hacker News Reader

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There are more major issues I would hope the article authors would correct. I know, not likely to happen. Here's a few notes to think about -

> The analysed star cluster IRS 13 is located 0.1 light years from the centre of our galaxy. This is very close in astronomical terms, but would still require travelling from one end of our solar system to the other twenty times to cover the distance.

If the "one end to the other" metric, at best, is 2 x 100,000 AU [1] if it means the edge of the Oort cloud. That's about 3.16 light-years.

But GCIRS 13E appears to be 26,000 light-years away. Hint: 3.16 light-years x 20 is not even close to 26,000 light-years.

The article never mentions any theories on the formation of these intermediate-mass black holes, or why confirming the existence of one in our own galaxy would be meaningful science.

[1] https://en.wikipedia.org/wiki/Oort_cloud

[2] https://en.wikipedia.org/wiki/GCIRS_13E

> But GCIRS 13E appears to be 26,000 light-years away. Hint: 3.16 light-years x 20 is not even close to 26,000 light-years.

The article isn't describing how far away from Earth IRS 13 is. It's describing how far from the galactic center it is (0.1 light-year, not 26,000 light-years).

To help narrow down what the author is referring to by "one end of our solar system to the other", one can divide 0.1 light-year by 20 to get 0.005 light-year, which is about 316 AU. I'm going to assume th⁹at the reference is to the heliosphere, then, since it's apparently about 300 AU across:

"The Sun's stellar-wind bubble, the heliosphere, a region of space dominated by the Sun, has its boundary at the termination shock. Based on the Sun's peculiar motion relative to the local standard of rest, this boundary is roughly 80–100 AU from the Sun upwind of the interstellar medium and roughly 200 AU from the Sun downwind."[1]

[1] https://en.wikipedia.org/wiki/Solar_System

My understanding is that the formation of intermediate mass black holes is pretty mysterious. In principle you could get those and the supermassive from stellar mass black holes colliding but in practice it takes more time than they’ve had.

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