In a recent study published in the Proceedings of the National Academy of Sciences, an international team of researchers led by Monash University in Australia have verified the existence of a rare hexagonal structure of diamond called lonsdaleite, within ureilite meteorites from the inside of a dwarf planet that formed approximately 4.5 billion years ago.
Lonsdaleite is named after Dame Kathleen Lonsdale, a famous British pioneering crystallographer responsible for developing several X-ray methods for studying crystal structures, and was the first woman elected as a Fellow to the Royal Society in 1945. This study holds the potential for further unlocking the secrets of the formation of our solar system, and was conducted with collaboration from RMIT University, the Australian Synchrotron and Plymouth University, and CSIRO.
Comets, with their long, beautiful, bright tails of ice, are some of the most spectacular sightings in the night sky. This was most apparent when Comet NEOWISE passed by Earth in the summer of 2020, dazzling viewers from all over the planet while being mainly visible in the northern hemisphere. Even though the sky might look the same night after night, comets are a humble reminder that the universe is a very active and beautiful place.
When Sicilian astronomer Giuseppe Piazzi spotted Ceres in 1801, he thought it was a planet. Astronomers didn’t know about asteroids at that time. Now we know there’s an enormous quantity of them, primarily residing in the main asteroid belt between Mars and Jupiter.
Ceres is about 1,000 km in diameter and accounts for a third of the mass in the main asteroid belt. It dwarfs most of the other bodies in the belt. Now we know that it’s a planet—albeit a dwarf one—even though its neighbours are mostly asteroids.
But what’s a dwarf planet doing in the asteroid belt?
When a young solar system gets going it’s little more than a young star and a rotating disk of debris. Accepted thinking says that the swirling debris is swept up in planet formation. But a new study says that much of the matter in the disk could face a different fate.
It may not have the honour of becoming part of a nice stable planet, orbiting placidly and reliably around its host star. Instead, it’s simply discarded. It’s ejected out of the young, still-forming solar system to spend its existence as interstellar objects or as rogue planets.
Planets form from the accumulation of countless grains of dust swirling around young stars. New computer simulations have found that planets begin forming earlier than previously thought, when a planet’s star hasn’t even finished forming yet.
Many planetary systems may get snuffed out before they even get a chance to form, according to new research. The culprit: nearby stars, capable of evaporating entire protoplanetary disks just when they begin to form.
200 light-years away from Earth, there’s a K-type main-sequence star named TOI (TESS Object of Interest) 178. When Adrian Leleu, an astrophysicist at the Center for Space and Habitability of the University of Bern, observed it, it appeared to have two planets orbiting it at roughly the same distance. But that turned out to be incorrect. In fact, six exoplanets orbit the smallish star.
And five of those six are locked into an unexpected orbital configuration.
I don’t know if you’ve noticed by now, but the Earth is a little bit wet. How Earth got all its water is one of the major mysteries in the formation of the solar system, and a team of Japanese researchers have just uncovered a major clue. But not on Earth – the clue is on Mercury.
For some time now, astronomers have known that the majority of systems in our galaxy consist of binary pairs rather than individual stars. What’s more, in recent decades, research has revealed that stars like our Sun are actually born in clusters within solar nebulas. This has led to efforts in recent years to locate G-type (yellow dwarf) stars in our galaxy that could be the Sun’s long-lost “solar siblings.”
And now, a new study by Harvard astronomers Amir Siraj and Prof. Abraham Loeb has shown that the Sun may once have once had a very similar binary companion that got kicked out of our Solar System. If confirmed, the implications of this could be groundbreaking, especially where theories on how the Oort Cloud formed and whether or not our system captured a massive object (Planet Nine) in the past.
The Milky Way has a number of satellite galaxies; nearly 60 of them, depedending on how we define them. One of them, called the Sagittarius Dwarf Spheroidal Galaxy (Sgr d Sph), may have played a huge role when it comes to humans, our world and our little civilization. A collision between the Milky Way and the Sgr d Sph may have created the Solar System itself.