As we all know, the stars we see in the night sky might already be dead. I was wondering though, when was this fact or conclusion commonly established? Today, most people (let's assume with an above average education) would probably be aware of this fact.

When is the earliest time when the same could be said? I am particularly interested if the same could be said for the time period revolving around the period 1850 - 1900.

I know that the speed of light was approximated fairly accurately in the 17th century. Knowing this (finite) speed, it's not hard for me to draw the conclusion that the source of the light I see may not be there anymore. Would this be an easy conclusion to draw a hundred years ago however? Maybe they thought stars don't die?


closed as off-topic by Emilio Pisanty, Jon Custer, Kyle Kanos, Aaron Stevens, ZeroTheHero Aug 5 at 2:47

  • This question does not appear to be about physics within the scope defined in the help center.
If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ ^As he said. en.wikipedia.org/wiki/History_of_supernova_observation $\endgroup$ – Signus Sep 19 '13 at 23:13
  • $\begingroup$ Ancient theories tended to have stars as being infinite, but you could also ask from the other direction: When did we have a theory that could explain why stars lived for so long? Once we understood chemistry and/or gravitational binding energy, these were proposed as sources of energy for the Sun, but geologists kept insisting Earth was billions of years old, far too long to be powered by such meager sources. $\endgroup$ – user10851 Sep 20 '13 at 2:42
  • 1
    $\begingroup$ The chances that any of the stars we see is already "dead" are very small. They are not far enough away to make it likely. $\endgroup$ – Rob Jeffries Jul 26 at 4:33
  • 5
    $\begingroup$ I'm voting to close this question as off-topic because, as per the site guidelines, it belongs on History of Science and Mathematics. $\endgroup$ – Emilio Pisanty Jul 28 at 16:16

Super novae were known a long time ago. But they were not understood as a the death throes of a star.

In spite of the apparent immutability of the heavens, Chinese astronomers were aware that new stars could appear. In 185 AD, they were the first to observe and write about a supernova, now known as the SN 185. The brightest stellar event in recorded history was the SN 1006 supernova, which was observed in 1006 and written about by the Egyptian astronomer Ali ibn Ridwan and several Chinese astronomers. The SN 1054 supernova, which gave birth to the Crab Nebula, was also observed by Chinese and Islamic astronomers.

But it wasn't until later we understood they had a life-cycle. The Greek philosopher Aristotle even proposed that the stars were made of a special element, not found on Earth, that never changes.

The Chinese might have been the first to suggest the idea as they took careful note of "guest stars" which suddenly appeared among the fixed stars.

It would seem that another person who suggested the idea was probably Tycho Brahe (14 December 1546 – 24 October 1601) as he coined the term nova meaning new star. And likely with this new mind set births brings deaths. He also is famous for realizing stars are very far away (due to parallax). In 1572 he witnessed a super nova and in 1573 he published a small book, "De nova stella" (The New Star) based on the super nova he saw. (Most super novae were assumed to be new stars, not dieing stars).

The event of understanding stars die probably just fell out of understanding what stars are. I'm not sure you can point to one event or person in history that could prove to know stars die prior to understanding stars themselves.


Conservation of energy dates back to ca. 1840. Once that was established, it was natural to suspect that a star had a finite lifetime, which could be calculated if its energy source was understood. The most popular theory in the 19th century was that stars converted gravitational energy into heat. Lord Kelvin also hypothesized that meteors crashed into the sun and resupplied it with energy. All of these mechanisms gave lifetimes for stars that were relatively short, and, e.g., too short to be consistent with the kinds of terrestrial timescales being proposed by Darwin and the geological gradualists. More info here: http://www.nobelprize.org/nobel_prizes/themes/physics/fusion/sun_1.html


Not the answer you're looking for? Browse other questions tagged or ask your own question.