Trans-Neptunian Object (TNO)

For the first time, scientists used the combined power of NASA's Hubble and James Webb Space Telescopes to study some of the most far-flung bodies in our solar system, trans-Neptunian objects (TNOs). Some are the smallest and faintest ever directly seen. The researchers unexpectedly found fewer small TNOs than expected and that the colors of these bodies followed the same relationships as those of their larger family members.

More than 3 billion miles (4.8 billion kilometers) from Earth, an ancient icy object is slowly awakening. As it drifts inward through the solar system, the frozen body known as Centaur 450P/LONEOS has begun releasing gas and dust—behavior more commonly associated with comets than with centaurs, the small icy objects that typically orbit between Jupiter and Neptune.

A team of professional and amateur Japanese astronomers have found evidence for a thin atmosphere around a small body in the outer solar system. The object is so small that it should not have a sustainable atmosphere, raising questions about when and how the atmosphere formed. Future observations to better characterize the atmosphere will help solve these mysteries.

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?