![]() It also allowed Römer to estimate the speed of light as 214,000 km/s. The different times for Io’s orbit reflected the different distances light had to travel. Römer realised his observations could be explained by the varying distance between Jupiter and Io, and Earth. ![]() The cumulative effect meant the predicted times could be in error by more than 10 minutes. At times when the Earth was moving away from Jupiter, the time between Io’s eclipses gradually increased as it moved closer the time decreased. Römer observed that the time between eclipses varied slightly depending on the time of year. ![]() The time for Io to make one complete circuit around Jupiter had been measured at 1.769 days. One of the ways sailors at sea checked their clocks was to observe the eclipse of Jupiter by its moon Io. Undaunted, Galileo concluded that light’s movement, “if not instantaneous, is extraordinarily rapid”.īut not long after, in 1676, we got a fair estimate of light’s speed from a young Danish astronomer by the name of Ole Römer. He had no such time keeping device and his reaction time would be way slower than that. The experiment failed dismally! To succeed, Galileo would have had to register a time difference of microseconds. Galileo would then time how long it took to see the return flash. The idea was that as soon as Galileo’s assistant saw the flash, he uncovered his lantern. He and an assistant perched themselves on distant mountaintops with covered lanterns. Galileo was among the first to think that light travelled at a finite speed. But why is it so?īefore the 1600s most people assumed light moved instantaneously. And that happens to be 299,792.458 kilometres per second. ![]() We all know the number one traffic rule of the universe – nothing can travel faster than the speed of light. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |