High up in Earth’s orbit, millions of human-made objects large and small are flying at speeds of over 15,000 miles per hour. The objects, which range from inactive satellites to

Of the seven Earth-sized worlds orbiting the red dwarf star TRAPPIST-1, one planet in particular has attracted the attention of scientists. This planet orbits the star within the “Goldilocks zone”—a

In the leading model of cosmology, most of the universe is invisible: a combined 95% is made of dark matter and dark energy. Exactly what these dark components are remains