Public
- Public
- Network
- Groups
- Popular
- People

Animation of a light echo. A star in the center of the frame sends out a spherical pulse of light. This hits three dust clouds at the right edge of the frame. Light, represented as red arrows, reflects off of the dust clouds and travels to the left, back towards the star. A blue arrow, representing light from the star also travels to the left. The camera pivots, so we are now looking at a frame where we see the star and gas clouds from the side. The arrows continue and they are now moving past the star towards the viewer. The blue line hits the frame first, and the star flashes. The red lines hit the frame later, and the clouds flash. This shows the delay between when the initial pulse from the star and when the reflected light reaches the viewer.

Download link

Animation of a light echo. A star in the center of the frame sends out a spherical pulse of light. This hits three dust clouds at the right edge of the frame. Light, represented as red arrows, reflects off of the dust clouds and travels to the left, back towards the star. A blue arrow, representing light from the star also travels to the left. The camera pivots, so we are now looking at a frame where we see the star and gas clouds from the side. The arrows continue and they are now moving past the star towards the viewer. The blue line hits the frame first, and the star flashes. The red lines hit the frame later, and the clouds flash. This shows the delay between when the initial pulse from the star and when the reflected light reaches the viewer.

Notices where this attachment appears

Kelly Lepo (kellylepo@astrodon.social)'s status on Thursday, 16-Nov-2023 19:09:00 UTC Kelly Lepo

You've heard of a sound echo: Sound bounces off of a surface and reflects back, causing a delay.
Did you know that light echos are also a thing? If there is a flash of light from something like a supernova, that light can hit interstellar clouds of dust and then reflect back, giving you light from the original supernova but on a delay.
We can use this delayed light to learn about what kind of star blew up in the supernova.
🎞️ https://www.spitzer.caltech.edu/video/ssc2008-09v2-dissecting-a-light-echo
#astronomy #space

In conversation about a year ago from astrodon.social permalink