At first glance, an image taken by NASA’s Spitzer Space Telescope looks like every Star Wars fan’s dream come true: Darth Vader’s lightsaber just hanging out in a galaxy far, far away.
In truth, it’s a galaxy that is far, far away — Galaxy NGC 5866, about 44 million light-years from Earth, to be exact. The red lightsaber appearance is because the entire galaxy can be seen on its side, according to a NASA release.
Spitzer allows us to glimpse the edge, which is why it looks like a beam of light, rather than how it might appear head-on. The red color appears because Spitzer detects infrared light and the red color in the image corresponds to an infrared wavelength typically emitted by dust, according to NASA.
The one structural detail astronomers can determine is that the galaxy likely has a flat dust disk around its outer region, which can form when galaxies merge. But there is no other sign of a merger, adding to the mystery.
Looking at this galaxy’s orientation doesn’t offer many clues to its actual shape or its cosmic history. But it’s not unlike when astronomers try to study our own galaxy, the Milky Way, which is like trying to study an entire forest while standing in the middle of it.
Ground and space-based observatories act like detectives on behalf of astronomers, seeking out the details of the universe obscured by distance, light and dust. Earlier this week, once-invisible ancient, massive galaxies were uncovered by the Atacama Large Millimeter/submillimeter Array in Chile.
And space observatories like Spitzer spot details in infrared that would never be captured by visible light telescopes.
The Spitzer Space Telescope is in NASA’s Great Observatories family. Spitzer detects infrared light, while Hubble captures visible and UV light, Compton was designed for gamma rays and Chandra sees X-rays.