Meteor experts don't think it's a meteor. Atmospheric scientists don't think it's lightning. The photographer insists that the streak and flash on the above image has not been created digitally. So what is it? Nobody is sure.

Where do comet tails come from? Although it is common knowledge that comet tails and comas originate from comet nuclei, exactly how that happens is an active topic of research. One of the best...

What does Comet Leonard look like from space? Today's featured image from Origin.Space's Yangwang-1 space telescope shows not only the currently bright comet -- but several other space delights as well. Taken...