Its observations like these that really give us an idea about how big the cosmos actually is. A star in a small galaxy called the Large Magellanic Cloud (LMC), some 160,000 light years from Earth, exploded as a massive supernova 400 years ago (Earth years that is). Combining the observations from an X-ray observatory and an optical telescope, scientists are currently observing the reflected light off galactic dust, only just reaching the Earth hundreds of years after the explosion…
Shakespeare’s first run the stage production, Hamlet, will have been in full-swing. Galileo might have been experimenting with his first telescope. Guy Fawkes could have been plotting to blow up the British parliament. These events all occurred around the beginning of the 17th Century when a bright point of light may have been seen in the night sky. This point of light, in the Large Magellanic Cloud (LMC), is a massive star exploding, ending its life in a powerful supernova.
Now, 400 years after the event, we can see a “supernova remnant” (SNR), and this particular remnant is known as SNR 0509-67.5 (not very romantic I know). The remnant of superheated gas slowly expands into space and still emits X-rays of various energies. The 400 year old explosion has even been imaged in great detail by the Chandra Observatory currently observing space in X-ray wavelengths. Analysis of the SNR indicates that it was most likely caused by a Type Ia supernova after analysis of the composition of the gases, in particular the quantities of silicon and iron, was carried out. It is understood that the supernova was caused when a white dwarf star in a binary system reached critical mass, became gravitationally unstable (due to fusion reactions in the core stopping) and exploded.
When SNR 0509-67.5 exploded all those years ago, it will have radiated optical electromagnetic radiation (optical light) in all directions of space. Now, for the first time, optical Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory (Chile) has observed reflected light from within the LMC originating from the supernova, 400 years after the event. Using the (reflected) optical light and X-ray emissions directly from the supernova remnant, scientists have been able to learn just how much energy was generated by the explosion.
Astronomers have even assembled a time-lapse video from observations of the light “echo” from 2001 to 2006. Although there are only five frames to the video, you can see the location of the reflected light change shape as different volumes of galactic dust are illuminated by the flash of supernova light. In each progressive frame, the clouds of gas that become illuminated will be further and further away from us, we are effectively looking further back in time as the light “echoes” bounce off the galactic matter.
An amazing discovery.
Source: Chandra X-ray Observatory
Hello! My name is Ian O’Neill and I’ve been writing for the Universe Today since December 2007. I am a solar physics doctor, but my space interests are wide-ranging. Since becoming a science writer I have been drawn to the more extreme astrophysics concepts (like black hole dynamics), high energy physics (getting excited about the LHC!) and general space colonization efforts. I am also heavily involved with the Mars Homestead project (run by the Mars Foundation), an international organization to advance our settlement concepts on Mars. I also run my own space physics blog: Astroengine.com, be sure to check it out!