Is there anything equal to speed of light? The speed of light c is exactly equal to 299,792,458 metres per second (approximately 300,000 kilometres per second; 186,000 miles per second; 671 million miles per hour)….Speed of light. Exact values kilometres per...
How can NASA look back in time? The JWST was designed to use a broad range of infrared light. And this is a key reason the JWST can see further back in time than Hubble. Galaxies emit a range of wavelengths...
What if we place a mirror 10 light-years away from Earth? If we put a giant mirror 10 light years away from Earth and looked at it through a telescope theoretically we’d see 20 years into the past. What would happen...
What is the farthest back in time we can see? So the furthest out we can see is about 46.5 billion light years away, which is crazy, but it also means you can look back into the past and try to...
Is looking into space looking back in time? Looking far out into the Universe is also looking back in time, so Hubble has now taken us to within a stone’s throw of the ‘Big Bang’ event itself. Hubble can now see...
Do mirrors work in space? At home or in space, mirrors must have completely smooth surfaces to make undistorted images. Making space mirrors involves particularly laborious and elaborate polishing, as this great photo of the Hubble Space Telescope’s mirror being polished...
What would you see if you looked at Earth from Mars? As seen from Mars, the Earth is an inner planet like Venus (a “morning star” or “evening star”). The Earth and Moon appear starlike to the naked eye, but observers...
What is the speed of light in km in a year? Light-year is the distance light travels in one year. Light zips through interstellar space at 186,000 miles (300,000 kilometers) per second and 5.88 trillion miles (9.46 trillion kilometers) per year....
At what speed does special relativity apply? Special relativity, developed by Albert Einstein, applies to situations where objects are moving very quickly, at speeds near the speed of light. Generally, you should account for relativistic effects when speeds are higher than...
Does time go slower in a car? The reason time slows down in a moving vehicle is because, according to the theory of relativity, the speed of light is constant. If the beam of light has to go farther than before...