en.wikipedia.org/wiki/Event_Horizon_Telescope
3 corrections found
100 μas corresponds to a linear distance of 6 billion pc
This distance scale is off by roughly ten orders of magnitude. Published EHT material gives 100 μas at z = 0.902 as about 0.803 parsecs, not 6 billion parsecs.
Full reasoning
The number in the article does not match the published EHT result for NRAO 530.
In the 2023 paper "The Event Horizon Telescope Image of the Quasar NRAO 530", the source is described as having redshift z = 0.902, and the paper states that 100 μas corresponds to a linear distance of 0.803 pc. An independent NRAO 530 study likewise gives 1 mas = 7.8 pc at this redshift, which implies 100 μas = 0.1 mas ≈ 0.78 pc.
So the article's value of 6 billion pc is not a small rounding difference; it is wildly inconsistent with the published scale and is even comparable to the source's cosmological distance, not the tiny linear size subtended by 100 microarcseconds. This appears to be a major unit/number typo.
2 sources
- The Astrophysical Journal, 943:170 (19pp), 2023 February 1
NRAO 530 has a redshift of z = 0.902 (Junkkarinen 1984), for which 100 μas corresponds to a linear distance of 0.803 pc.
- High-frequency very long baseline interferometry studies of NRAO 530 | Monthly Notices of the Royal Astronomical Society | Oxford Academic
At a redshift of 0.902 ... 1 mas of angular separation corresponding to 7.8 pc ...
On March 22, 2024, the EHT Collaboration released an image of Sagittarius A* in polarized light.
The polarized Sagittarius A* image was released on March 27, 2024, not March 22, 2024.
Full reasoning
The release date in the article is five days early.
Multiple official announcements from institutions in the EHT collaboration date the polarized-light image of Sagittarius A* to March 27, 2024. ESO's press release is dated 27 March 2024 and says the results were "published today." The University of Arizona's release is also dated March 27, 2024 and says the results were published that day.
So the statement that the EHT released this image on March 22, 2024 is incorrect.
2 sources
- Astronomers unveil strong magnetic fields spiraling at the edge of Milky Way's central black hole | ESO
Press Release ... 27 March 2024 ... This research was presented in two papers by the EHT Collaboration published today ...
- Astronomers capture magnetic fields twirling around black hole | University of Arizona News
University Communications March 27, 2024 ... The results were published on March 27 in the journal The Astrophysical Journal Letters.
James Clark Maxwell Telescope (JCMT)
The observatory's name is wrong. JCMT stands for the James Clerk Maxwell Telescope, not the James Clark Maxwell Telescope.
Full reasoning
This caption misspells the name of the JCMT.
The observatory's official website names it the James Clerk Maxwell Telescope. An official EHT-partner press release from ESO also lists the 2017 array member as the James Clerk Maxwell Telescope (JCMT).
So "James Clark Maxwell Telescope (JCMT)" is incorrect; the correct name is James Clerk Maxwell Telescope (JCMT).
2 sources
- James Clerk Maxwell Telescope - Operated by East Asian Observatory
James Clerk Maxwell Telescope Operated by East Asian Observatory
- Astronomers unveil strong magnetic fields spiraling at the edge of Milky Way's central black hole | ESO
The individual telescopes involved in the EHT in April 2017 ... the James Clerk Maxwell Telescope (JCMT) ...