Solar System Archives (2025)

Mercury, the closest planet to our Sun, is also one of the least understood in the Solar System. On the one hand, it is similar in composition to Earth and the other rocky planets, consisting of silicate minerals and metals differentiated between a silicate crust and mantle and an iron-nickel core. But unlike the other rocky planets, Mercury’s core makes up a much larger part of its mass fraction. Mercury also has a mysteriously persistent magnetic field that scientists still cannot explain. In this respect, Mercury is also one of the most interesting planets in the Solar System.

But according to new research, Mercury could be much more interesting than previously thought. Based on new simulations of Mercury’s early evolution, a team of Chinese and Belgian geoscientists found evidence that Mercury may have a layer of solid diamond beneath its crust. According to their simulations, this layer is 15 km (9 mi) thick sandwiched between the core and the mantle hundreds of miles beneath the surface. While this makes the diamonds inaccessible (for now, at least), these findings could have implications for theories about the formation and evolution of rocky planets.

Continue reading “Mercury Could be Housing a Megafortune Worth of Diamonds!”

It should not be surprising that Venus is dry. It is famous for its hellish conditions, with dense sulphurous clouds, rains of acid, atmospheric pressures comparable to a 900 meter deep lake, and a surface temperature high enough to melt lead. But it’s lack of water is not just a lack of rain and oceans: there’s no ice or water vapour either. Like Earth, Venus is found within our Solar System’s goldilocks zone, so it would have had plenty of water when it was first formed. So where did all of Venus’s water go?

Continue reading “Where Did Venus's Water Go?”

Does another undetected planet languish in our Solar System’s distant reaches? Does it follow a distant orbit around the Sun in the murky realm of comets and other icy objects? For some researchers, the answer is “almost certainly.”

Continue reading “New Evidence for Our Solar System’s Ghost: Planet Nine”

Untangling what happened in our Solar System tens or hundreds of millions of years ago is challenging. Millions of objects of wildly different masses interacted for billions of years, seeking natural stability. But its history—including the migration of the giant planets—explains what we see today in our Solar System and maybe in other, distant solar systems.

New research shows that giant planet migration began shortly after the Solar System formed.

Continue reading “The Giant Planets Migrated Between 60-100 Million Years After the Solar System Formed”

The dwarf planet Ceres has some permanently dark craters that hold ice. Astronomers thought the ice was ancient when they were discovered, like in the moon’s permanently shadowed regions. But something was puzzling.

Why did some of these shadowed craters hold ice while others did not?

Continue reading “Ice Deposits on Ceres Might Only Be a Few Thousand Years Old”

Everyone knows that solar energy is free and almost limitless here on Earth. The same is true for spacecraft operating in the inner Solar System. But in space, the Sun can do more than provide electrical energy; it also emits an unending stream of solar wind.

Solar sails can harness that wind and provide propulsion for spacecraft. NASA is about to test a new solar sail design that can make solar sails even more effective.

Continue reading “NASA’s Next Solar Sail is About to Go to Space”

The edge of the Solar System is defined by the heliosphere and its heliopause. The heliopause marks the region where the interstellar medium stops the outgoing solar wind. But only two spacecraft, Voyager 1 and Voyager 2, have ever travelled to the heliopause. As a result, scientists are uncertain about the heliopause’s extent and its other properties.

Some scientists are keen to learn more about this region and are developing a mission concept to explore it.

Continue reading “Want to Leave the Solar System? Here’s a Route to Take”

Universe Today has had some fantastic discussions with researchers on the importance of studying impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, and planetary geophysics, and how these diverse scientific fields can help researchers and the public better understand the search for life beyond Earth. Here, we will investigate the unique field of cosmochemistry and how it provides researchers with the knowledge pertaining to both our solar system and beyond, including the benefits and challenges, finding life beyond Earth, and suggestive paths for upcoming students who wish to pursue studying cosmochemistry. But what is cosmochemistry and why is it so important to study it?

Continue reading “Cosmochemistry: Why study it? What can it teach us about finding life beyond Earth?”

Astronomers discovered another asteroid sharing Mars’ orbit. These types of asteroids are called trojans, and they orbit in two clumps, one ahead of and one behind the planet. But the origins of the Mars trojans are unclear.

Can this new discovery help explain where they came from?

Continue reading “An Asteroid Found Sharing the Orbit of Mars”

Nature often defies our simple explanations. Take comets and asteroids, for example. Comets are icy and have tails; asteroids are rocky and don’t have tails. But it might not be quite so simple, according to new research.

Continue reading “Citizen Scientists Find Fifteen “Active Asteroids””