Science ❯ Astronomy

Planetary Characteristics

Brightness Venus Mercury Super-Earths Size and Shape Planetary Atmospheres Atmospheric Conditions Mass and Size Temperature Planetary Features

Mars and Uranus Form an Unusually Close Predawn Pairing on July 4

This optical appulse will let observers use bright Mars as a guide to find the faint ice giant Uranus before sunrise.

TESS Confirms Two Jupiter‑Sized Super‑Puff Planets

Three Planets Will Form a Brief Evening Mini-Alignment in Early June

Study Challenges 'Ice Giant' Label for Uranus and Neptune

Six-Planet Parade to Line Up in Saturday’s Twilight Sky

JWST Charts Uranus’s Upper Atmosphere in 3D, Exposing Auroral Bands and a Cooling Trend

Mercury Retrograde Begins Feb. 26 in Pisces, Running Through March 20

Six-Planet Parade Peaks Feb. 28 After Sunset: When, Where and How to Watch

Six-Planet Parade to Peak on Feb. 28, but Only Some Will Be Visible Without Optics

Juno Radio Occultations Sharpen Jupiter’s Dimensions, Reveal Greater Oblateness

Earth-Sized Exoplanet Candidate Found 146 Light-Years Away Around a K-Dwarf

Jupiter at Opposition Tonight, Brightest and Largest of 2026

Webb Finds Carbon-Rich Atmosphere on Lemon-Shaped Planet Orbiting a Pulsar

Saturn's Rings Seem to Vanish in Rare Edge-On Alignment on Nov. 23–24

Scientists Detect Habitable-Zone ‘Super‑Earth’ GJ 251 c Just 18 Light‑Years Away

Webb Spots Tiny New Moon Around Uranus, Bringing Count to 29

NASA to Target Super-Earth TOI-1846 b With James Webb Space Telescope

Study Reveals Jupiter Was Once Twice Its Current Size with a Magnetic Field 50 Times Stronger

Astronomers Confirm Super-Earths Are Common in Distant Orbits Across the Milky Way

Uranus’ Day Found to Be 28 Seconds Longer Than Previously Measured