'Weird Object' Discovered Beyond Neptune: A Clue in the Quest for Planet Nine?

The newly discovered object called Niku is a real oddity (artist's conception). It is also part of a group of many such objects far past Neptune in the outer Solar System. Image Credit: ESO/L. Calçada/Nick Risinger

The newly discovered object called Niku is a real oddity (artist’s conception). It is also part of a group of many such objects far past Neptune in the outer Solar System. Image Credit: ESO/L. Calçada/Nick Risinger

For the most part, the Solar System seems to be a rather well-ordered place; the planets, dwarf planets, […]

New Worlds Galore: Kepler Space Telescope Confirms 1,284 More Exoplanets

Artist's conception of the many different exoplanets which have been discovered by Kepler so far. Image Credit: NASA/W. Stenzel

Artist’s conception of the many different exoplanets that have been discovered by Kepler so far. Image Credit: NASA/W. Stenzel

For several years now the Kepler Space Telescope, as well as other telescopes, has been discovering an increasing number of exoplanets, with over 2,000 such confirmed worlds found so far (and nearly 5,000 candidates). Today, NASA […]

Is 'Planet 9' Really a Second Massive Kuiper Belt?

The Kupier Belt is a massive collection of dwarf planet and asteroid-sized worlds orbiting far past Neptune. Is the hypothetical Planet 9 really a second such belt? Image Credit: T. Pyle (SSC)/JPL-Caltech/NASA

The Kuiper Belt is a massive collection of dwarf planet- and asteroid-sized worlds orbiting far past Neptune. Is the hypothetical Planet 9 really a second such belt? Image Credit: T. Pyle (SSC)/JPL-Caltech/NASA

The announcement of a possible large ninth planet in our Solar System way beyond Neptune last month caused a lot of excitement, […]

Mysterious World: 30 Years Since Voyager 2's Encounter With Uranus (Part 2)

Uranus and its six largest moons, from left Puck, Miranda, Ariel, Umbriel, Titania and Oberon. Image Credit: NASA

Uranus and its six largest moons, from left Puck, Miranda, Ariel, Umbriel, Titania, and Oberon. Image Credit: NASA

At 12:59 p.m. EST (5:59 p.m. GMT) today, exactly three decades passed since NASA’s Voyager 2 spacecraft became the first machine fashioned by human hands to visit Uranus, the seventh planet in line from the Sun. […]

Uncertain Journey: 30 Years Since Voyager 2's Encounter With Uranus (Part 1)

Visible only as a crescent, Uranus recedes from Voyager 2 in the days after Closest Approach. Photo Credit: NASA

Visible only as a crescent, Uranus recedes from Voyager 2 in the days after Closest Approach. Photo Credit: NASA

Thirty years ago, today and tomorrow, NASA’s Voyager 2 spacecraft gave humanity its first close-up glimpse of Uranus. Known for more than two centuries, and frequently the “butt” of many off-color jokes, this giant gaseous […]

Has 'Planet X' Finally Been Found? A Cautionary Tale

Artist's conception of Planet Nine. Image Credit: Image: Caltech/R Hurt (IPAC)

Artist’s conception of Planet Nine. The new evidence is the best so far that a massive planet exists far past Neptune in the outer Solar System. Image Credit: Caltech/R. Hurt (IPAC)

For a long time now, there have been theories and rumors regarding the possible existence of another planet in our Solar System, far […]

A Moon Falling Apart: Grooves on Phobos Are a Sign of its Eventual Catastrophic Fate

The unusual grooves on Phobos' surface, such as those on the left side of this image, are now thought to be caused by tidal stress. The large crater Stickney is in the upper portion of the image. Image Credit: NASA/JPL-Caltech/University of Arizona

The unusual grooves on Phobos’ surface, such as those on the left side of this image, are now thought to be caused by tidal stress. The large crater Stickney is in the upper portion of the image. Image Credit: NASA/JPL-Caltech/University of Arizona

Phobos is the largest of Mars’ two tiny moons, but 50 million […]

Back to the Ice Giants: Proposed New Mission Would Re-Visit Uranus or Neptune (or Both!)

Uranus (left) and Neptune (right). These two ice giants and their many moons are awaiting further exploration. Image Credit: NASA

Uranus (left) and Neptune (right). These two ice giants and their many moons are awaiting further exploration. Image Credit: NASA

The outer Solar System has been a busy place lately, with the ongoing Cassini mission at Saturn and New Horizons’ recent spectacular flyby of Pluto. Literally in-between those two worlds, however, it has been […]

One Day to Pluto: Looking Back at Humanity's First-Time Successful Encounters With the Sun's Planets

Tomorrow’s historic flyby of the dwarf planet Pluto and its binary companion, Charon, will mark the completion of humanity’s first-time exploration of each of the Solar System’s nine traditional planets. Photo Credit: NASA

Tomorrow, the United States will become the first nation to have conducted a close-range reconnaissance of all nine “traditional” planets in […]

The Science of Pluto: The Gates of the Planetary Underworld (Part 1)

A computer-generated impression of the view from the surface of Pluto. The Sun looks like a very bright star on the sky (upper right), while Charon, Pluto’s biggest satellite, looms large near the horizon (at left). The scientific study of the Pluto-Charon system, has been one of expanding horizons and increased awareness of our […]