We’ve been using the Hubble Space Telescope to watch a jet of material coming out of galaxy NGC 3862 for over twenty years. Only recently, after piecing together a string of pictures, have we seen what’s really happening.
The black hole at the center of NGC 3862 galaxy has been shooting out massive jets of plasma for a long time. The ejections form little bundles, like glowing bullets. In the last two decades, the black hole has ejected one “bullet” so fast that it has smashed into the back of the previous bullet, causing them both to glow.
We’ve just recently noticed that, despite the fact that the Hubble Telescope has been taking pictures of the galaxy for twenty years. The images, though sharp, were still. It was only when a researcher at the Space Telescope Science Institute, who wanted to study the motion of the matter, took a look at the images in sequence that the collision became apparent. The video above is a sequence of still image made into a “film” to make the motion more apparent.
Scientists don’t know exactly why the later material moved faster than the earlier one, but think it might be because the first jet clears a path through the material in space, cutting down the resistance felt by later bundles of material.
Images: Credit: NASA, ESA, and E. Meyer (STScI)