Look into the night sky and you'll glimpse the stars from hundreds of billions of galaxies. Some galaxies are swirling blue disks like our own Milky Way, others are red spheres or misshapen, clumpy ...

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. These levitating spheres may appear red, purple or green at first glance, but in actuality, all ...