Solar System

NASA has released the first significant findings from the Parker Solar Probe's first two close encounters with the Sun that began in November 2018. Four new studies outline how the spacecraft has both confirmed theories and sprung a few surprises.

An instrument aboard NASA's New Horizons is sending back data that could help scientists predict when the unmanned deep-space probe will reach interstellar space. Using the SWAP instrument, scientists are learning more about the solar winds.

In 2006, Pluto was downgraded from planet to dwarf planet – and now, based on the same definition an object in the asteroid belt may need to be upgraded from asteroid to dwarf planet. New observations of asteroid Hygiea suggest it fits the criteria.

The discovery of 20 new moons around Saturn brings its total to 82 – three more than Jupiter, which was previously thought to hold the record.

A strange object recently discovered in our solar system has been confirmed to be interstellar in origin, and it now has an official name: 2I/Borisov.

Data from the Juno probe found that Jupiter's core is less dense and more spread out than expected. Now, astronomers believe they have an answer – a huge ancient planet, with 10 times the mass of Earth, crashed into the gas giant in the early days of the solar system.

When scientists need to learn about something, recreating it in the lab is often one of the best ways – and now that even applies to the Sun itself. Physicists from the University of Wisconsin-Madison have built a mini-Sun in the lab, and used it to probe the secrets of the real thing.

The Japanese spacecraft Hayabusa 2 has successfully pulled off a second touchdown on the surface of the distant asteroid Ryugu. The risky dive saw the probe collect material that had been exposed during the creation of an artificial crater on April 5.

Saturn sports an impressive ring system, but Uranus also has some, although they’re usually too faint to see without a powerful telescope. Striking new images shows these rings in very clear detail thanks to thermal imaging, allowing astronomers to measure their temperature for the first time.

An international team of physicists has finally found proof of circumplanetary disks, adding substantial weight to current theoretical models of planet formation. These disks of gas surrounded by dust have eluded detection, until now.

New research suggests some asteroids could actually be alien, captured during close flybys with other star systems. These close encounters could also explain objects like Oumuamua and might even provide an alternative to the “Planet Nine” hypothesis.

According to research by planetologists at the University of Münster, the collision with a Mars-sized planetoid that formed the Moon 4.4 billion years ago brought with it almost all the water that makes our planet habitable.