Since the distance from Earth to Mars changes drastically as the planets orbit the Sun, Mars’ appearance changes dramaticaly. Mars is bright now, and it’s getting closer and brighter still […]

Why does asteroid 2015 BZ509 orbit the Sun the backwards? As shown in the featured animation, Jupiter’s trojan asteroids orbit the Sun in two major groups — one just ahead […]

How many of these can you find in today’s featured photograph: an aurora, airglow, one of the oldest impact craters on the Earth, snow and ice, stars, city lights, and […]

Does it rain on the Sun? Yes, although what falls is not water but extremely hot plasma. An example occurred in mid-July 2012 after an eruption on the Sun that […]

This stunning group of galaxies is far, far away, about 450 million light-years from planet Earth and cataloged as galaxy cluster Abell S0740. Dominated by the cluster’s large central elliptical […]

Named for a cosmic cloud hunter, Australian astronomer Colin Stanley Gum (1924-1960), The Gum Nebula is so large and close it is actually hard to see. In fact, we are […]

This galaxy is having a bad millennium. In fact, the past 100 million years haven’t been so good, and probably the next billion or so will be quite tumultuous. Visible […]

Why does the right part of this image of the Moon stand out? Shadows. The terminator line — the line between light and dark — occurs in the featured image […]

How do Jupiter’s clouds move? To help find out, images taken with NASA’s Juno spacecraft during its last pass near Jupiter have been analyzed and digitally extrapolated into a time-lapse […]

Posing near the western horizon, a brilliant evening star and slender young crescent shared reflections in a calm sea last Thursday after sunset. Recorded in this snapshot from the Atlantic […]