Trans-Neptunian Object (TNO)

Using preliminary data from the Vera C. Rubin Observatory, scientists have discovered over 11,000 new asteroids. The data were confirmed by the International Astronomical Union's Minor Planet Center (MPC), making this the largest single batch of asteroid discoveries submitted in the past year. The discoveries were made using data from Rubin's early optimization surveys and offer a powerful preview of the observatory's transformative impact on solar system science.

Our solar system hosts almost 900 known moons; more than 400 orbit the eight planets while the remaining orbit dwarf planets, asteroids, and Trans-Neptunian Objects (TNOs). Of these, only a handful are targets for astrobiology and could potentially support life as we know it, including Jupiter's moons Europa and Ganymede, and Saturn's moons Titan and Enceladus. While these moons orbit two of the largest planets in our solar system, what about moons orbiting giant exoplanets, also called […]

A Southwest Research Institute-led team has reported the first detection of gas on the distant dwarf planet Makemake, using NASA's James Webb Space Telescope (JWST). This discovery makes Makemake only the second trans-Neptunian object, after Pluto, where the presence of gas has been confirmed. The gas was identified as methane.

Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers had put it forward as an explanation for Uranus's orbit, which drifts from the path of orbital motion that physics would expect it to follow. The gravitational pull of an undiscovered planet, several times larger than Earth, was seen as a possible reason for the discrepancy.

Trans-Neptunian objects (TNO) are some of our solar system's lesser-known objects. They number in the thousands, and they get their name from their orbits. These dwarf planets orbit the sun at a greater average distance than Neptune does. Pluto is the group's most well-known member, having been demoted from planet to TNO in recent years.

A team of astronomers led by the Center for Astrophysics | Harvard & Smithsonian has discovered a rare object far beyond Neptune, from a class known as trans-Neptunian objects, that is moving in rhythm with the giant planet. This object, called 2020 VN40, is the first confirmed body that orbits the sun once for every ten orbits Neptune completes.

If our solar system seems stable, it's because our short lifespans make it seem that way. Earth revolves, night follows day, the moon moves through light and shadow, and the sun hangs in the sky. But in reality, everything is moving and influencing everything else, and the fine balance we observe can easily be disrupted. Could passing stars have disrupted Earth's orbit and ushered in dramatic climatic changes in our planet's past?

A group of astronomers from across the globe, including a team from the University of Washington and led by Queen's University Belfast, have revealed new research showing that millions of new solar system objects will be detected by a brand-new facility, which is expected to come online later in 2025.

For centuries, astronomers have sought to understand the formation and evolution of the solar system and the dynamics that govern it. In particular, there is the long-standing question of whether or not the planets' orbits will remain stable over time. However, these studies have generally treated the solar system as an isolated system, focusing solely on the gravitational interactions between the planets. This is in spite of the fact that astronomers have known for some time that stars in the […]

In the cold, dark outskirts of planetary systems far beyond the reach of the known planets, mysterious gas giants and planetary masses silently orbit their stars—sometimes thousands of astronomical units (AU) away. For years, scientists have puzzled over how these "wide-orbit" planets, including the elusive Planet Nine theorized in our own solar system, could have formed. Now, a team of astronomers may have finally found the answer.