What is the dimmest star in the constellation Leo?
The dimmest star would be one so dim that we can’t see it even with the best telescope, and therefore one that has never even been discovered. If you don’t limit the stars to those in this galaxy it would certainly be some small insignificant star in some distant galaxy in Leo that in itself is only a faintly discernible smudge even with the best telescopes. As for an example of a dim star, I have the complete Tycho-2 star catalogue loaded onto this computer. A quick browse revealed the imaginatively titled Tycho 1431-1042-1 at a lowly magnitude 12.68. That certainly isn’t the faintest star known – the Hubble guide star catalogue goes much fainter than Tycho-2 for instance, but that star is already over 250 times too faint to see with the naked eye under even the darkest sky.
