Talk:Historical brightest stars

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Initiative from here: Talk:List of brightest stars Said: Rursus (☻) 18:48, 30 October 2008 (UTC)

Variable giants, bright giants, and supergiants

Aren't some stars, especially supergiants extremely variable in visual brightness over comparatively short times (100,000 years)? How can you say that, forex, ε CMa is the brightest millions of years ago when it was probably a much different star visually? Chasrob (talk) 15:45, 6 March 2011 (UTC) The original article about this pointed out that the errors in its proper motion etc could make a difference of up to a magnitude, making a nonsense of the 0.01 mag precision quoted! And of course the name of the list is wrong -- this was prehistoric, and events in the future are certainly not historic! 'Brightest stars over time' would be more accurate, but I'm not familiar enough with Wikipedia to know how changing this will affect other links.Robin Scagell (talk) 14:49, 6 February 2013 (UTC)

True, and there's another just as weak spot, and more difficult to assess: Tomkin is working from values of 1) proper motion and 2) radial velocity (movement along the sightline from the earth to a given star), and at least for the second one, we only have those values for a very short period, essentially the modern age of large telescopes. She's assuming that both sets of values will remain constant for any given star over millions of years. That's a tall call, because those values are really reflections of the real 3-D motion of the observed star through space and the 3-D movement of the sun through the Milky Way; we cannot measure the first one directly (plus the more oblique it is vs the sun the harder it will be to determine accurately) and there is nothing surprising about the option that the orbital speed or direction of a star could change as it moves along its orbit around the Milky Way. The planets have different velocities at different points in their orbits, depending on how far away they are from the sun, so the stars should be expected to have some alterations too. And if a star passes fairly close to something heavy (like, the Orion Nebula) or is impacted by the exlosive surge of a supernova, it could be expected to have its orbit swayed a bit too; this change to its orbit will then remain, it won't "return" to the previous angle. Those possibilities are left aside by Tomkin, and they are of course impossible to predict or calculate at present. But they make it clear that her table is very much an approximation. 83.251.170.27 (talk) 11:33, 16 April 2016 (UTC)

Sun

Shouldn't the Sun be listed as the brightest? ~ ~ ~ ~ 32ieww (talk) 00:50, 29 December 2016 (UTC)

Evolution of stars

Does this table take into account the evolution of stars? Because it is possible that some of the stars might explode and turn into white dwarfs and not be the brightest star when the time comes. EternalNub (talk) 03:55, 1 March 2024 (UTC)