3 ms·
1st 'graph of the related paper explains the significance: Ultrafaint dwarf galaxies are critical probes of the properties of dark matter and the physical driv
by dredmorbius 2y ago
1st 'graph of the related paper explains the significance:
Ultrafaint dwarf galaxies are critical probes of the properties of dark matter and the physical drivers of galaxy formation at very low mass scales. In the roughly two decades since their first discovery, tens of ultrafaint satellite galaxies of the Milky Way have been discovered. As individual systems, they are extremely dark matter dominated and most appear to have primarily early star formation that is impacted strongly by reionization.
<https://iopscience.iop.org/article/10.3847/2041-8213/adb433/pdf https://iopscience.iop.org/article/10.3847/2041-8213/adb433/...>
To be fair, this is the paper on which the article is presumably based rather than TFA itself, though I (as apparently others) was unable to read the linked source due to the indeed ridiculously stringent CAPTCHA.
Obvious reasons why faint dwarf galaxies proximate to our own home galaxy might be more observable than even those of our nearest (large) galactic neighbour are obvious, and are a trivial tangent not worth elaboration.
- sega_sai 2y agoI work in this field and written papers on these objects, so I am aware of their significance. This is exactly why I left the comment for people to know whether that's something particularly novel or interesting (for non-experts) or not.
- dredmorbius 2y agoWhat's notable is less the faintness, and more the distance / proximity. I don't know that this is the most distant very faint dwarf satellite observed, but it is the faintest orbiting the Andromeda galaxy, to date. That may speak to observations not possible with nearer VFDGs, or speak to new observational methods / techniques / equipment which made the observation possible. I'd hope that someone working in the field (I do not) might be able to comment more substantively on such matters, rather than quibble over the relatively uninteresting fact that nearer VFDGs have been observed with far lower absolute luminosity, which ... is rather to be expected.