Space News & Blog Articles

Mercury is one of the four rocky planets of the Solar System, yet its chemistry is very different from Earth, Venus, and Mars. Missions to the planet show that it has an iron-poor, but sulfur- and magnesium-rich crust, which has implications for its interior makeup. Furthermore, it's known to planetary scientists as the most reduced planet in the Solar system. That means the chemicals it contains are dominated by sulfides, carbides, and silicides, as opposed to oxides like we see here on Earth.

Astronomers don't have to work hard to find binary stars in the Milky Way. They're common, even abundant. For a long time, they thought that these stars are unlikely to host exoplanets. The complex gravitational environment made things so chaotic, so the thinking went, that the planet formation process is disrupted.

One of the most intriguing puzzles in cosmology is the existence of supermassive black holes that seem to appear very early in the history of the Universe. Astronomers keep finding them at times when, by all that they understand about the infant Universe, they shouldn't be there. The standard theory of black hole formation suggests that they hadn't enough time to grow as massive as they appear to be. Yet, there they are, monster black holes with the mass of at least a billion suns. The James Webb Space Telescope (JWST) has found a large population of them in early epochs, and they've been observed in very early quasars as well by such missions as the Chandra X-Ray Observatory.

In a first, ESA’s Proba-3 space-based coronagraph tracks space weather back to its source.

Laser sail propulsion is an idea that won't go away. By aiming powerful Earth-based lasers at tiny spacecraft with light sails, tiny spacecraft can be accelerated to near-relativistic speeds without carrying fuel or an energy source, and without carrying any kind of propulsion system at all. There are clear advantages to this idea, if it can be implemented.

Our Sun is a patient rotator. Over its lifetime it has shed angular momentum steadily, swept away on the solar wind, slowed by the invisible drag of its own magnetic field. From birth to death, stars typically spin down to between a hundred and a thousand times slower than their original rotation rate. It's one of the most reliable patterns in stellar physics, and astronomers have long assumed that magnetic fields interacting with the churning plasma inside a star were the mechanism behind it.

Think of the night sky and you probably picture stars as individual points of light, scattered at random. But stars are rarely born alone. They arrive in vast clusters, forged deep inside enormous clouds of gas, and within each cluster the variety is staggering. Some stars are cool, dim, and modest, only a fraction of the Sun's bulk. Others are stellar monsters, ten times heavier than our Sun and blazing with a hundred thousand times its brilliance. They burn fast and die young, but while they last, they dominate everything around them.

I have spent a fair amount of time thinking about what happens to the human body and mind under extreme conditions. But here is something I had not fully considered… when astronauts arrive in space after a lifetime on Earth, their brains still think gravity is there. And that turns out to matter rather a lot.

On top of Kitt Peak in the Arizona Desert, a robotic surveyor just completed a five year mission to catalogue the positions of tens of millions of galaxies. The Dark Energy Spectroscopic Instrument (DESI) has now created the largest, most detailed 3D map of our universe ever constructed. And it’s not done yet, its main mission has been extended through 2028.