Light Echoes Solve Mystery of Tycho's Supernova

Ponca City, We love you writes "Powerful telescopes in Hawaii and Spain are using 'light echoes' from the original supernova explosion that have bounced off dust in the surrounding interstellar clouds to identify the precise type of supernova that Tycho Brahe saw 436 years ago. Although the echoed light from Tycho's supernova is around 20 billion times fainter than the original light observed in 1572, the team took identical images of the sky a few months apart and then digitally subtracted one from the other to find evidence for several sets of light echoes rippling across patches of dust in the northern Milky Way. 'Using light echoes in supernova remnants is time-travelling in a way, in that it allows us to go back hundreds of years to observe the first light from a supernova event. We got to relive a significant historical moment and see it as the famed astronomer Tycho Brahe did hundreds of years ago,' said Tomonori Usuda, of the Subaru Telescope in Hawaii. Tycho's original observations were particularly important as he immediately concluded that the new star, visible even by day, could not be closer than the Moon challenging the Aristotelian view of the cosmos, widely accepted since ancient times, which held that the sky beyond the Moon never changed."

Comments

Wikipedia links just for the sake of completeness

[Anonymous Coward]

Here's a link to the supernova in question. Also, here's Brahe himself. Remember that all his observations were naked-eye - pre telescopes.

Reverse Ray Tracing

[Doc Ruby]

When can we point our telescopes at an object hundreds or thousands of lightyears distant, and pick up the light reflected back at us that previously traveled from Earth to that object, then reassemble it into images? Images of the Earth's past, twice as old as the lightyear distance of the object?

We could look at an object 1000 lightyears distant for reflections of Jesus being crucified. Search among objects 250-600 lightyears distant for reflections of people arriving in the "Americas" on ships before Columbus. 176ly distant objects could show us images of Newton getting hit by a falling apple.

Finally a use for the combined computing power of all Earth's computers.

Re:Light echoes?

[mrsquid0]

North in the sky is defined to be the point directly above the Earth North Pole of rotation. The northern half of the sky is the part of the sky between the celestial equator and the north celestial pole. For a planet north is defined using the right hand rule of rotation. Curl the fingers of your right hand. That is the direction of the planet's rotation. Stick out your right thumb. That is the direction of the planet's north pole. The same rule applies to Galactic north. Just apply the rotation rule to the Galaxy. Once you get outside the Galaxy supergalactic coordinates are used, which are defined here: http://en.wikipedia.org/wiki/Supergalactic_plane.