When a periodic comet flies by the Sun enough times, it can become depleted of its volatile elements. Once it is depleted, what distinguishes it from an asteroid, other than records of past sightings

Neutrons can, especially in extreme circumstances (and large concentrations) emit electromagnetic radiation. I specifically asked about this in Physics S.E. Has a free neutron ever been shown to ab…

Magnetosphere Astronomy dictionary, letter M It is the outermost region of the Earth's atmosphere, also known as the exosphere. It extends above the ionosphere, starting at 500 km. In this region the ionized particles are governed by the Earth's magnetic field and form a characteristic envelope modeled by the lines of force of the magnetic field and by the interaction with the Solar Wind.

So, recently I was shopping for telescopes and I decided on the following telescope: https://www.amazon.com/Celestron-21049-127EQ-PowerSeeker-Telescope/dp/B0007UQNKY/ I had exactly $180 to spend,…

I was reading up on Bootes void and came across this list of the largest voids in the visible universe, and apparently the one we're in, the KBC void, is not only the biggest, but damned-near spher…

If I've taken an image of the Galactic bulge with the pixel units in MJ per steradian: and I've looked down each column of the image and added up the values: then do the units change? My thinking…