In recent years, astronomers have been looking to refine our understanding of how the Solar System formed. On the one hand, you have the traditional Nebular Hypothesis which argues that the Sun, the planets, and all other objects in the Solar System formed from nebulous material billions of years ago. However, astronomers traditionally assumed that the planets formed in their current orbits, which has since come to be questioned.
How long can a rocky world withstand the blast from a red dwarf star
Red dwarf stars have become a major focal point for exoplanet studies lately, and for good reason. For starters, M-type (red dwarf) stars are the most common type in our Universe, accounting for 75% of stars in the Milky Way alone. In addition, in the past decade, numerous terrestrial (i.e rocky) exoplanets have been discovered orbiting red dwarf stars, and within their circumstellar habitable zones (“Goldilocks Zones”) to boot.
Flying chariots and exotic birds: how 17th century dreamers planned to reach the moon
The Genesis Project: using robotic gene factories to seed the galaxy with life
In the past decade, the rate at which extra-solar planets have been discovered and characterized has increased prodigiously. Because of this, the question of when we might explore these distant planets directly has repeatedly come up. In addition, the age-old question of what we might find once we get there – i.e. is humanity alone in the Universe or not? – has also come up with renewed vigor.
You don’t need to build a rocket to prove the Earth isn’t flat – here’s the simple science
Galactic panspermia: Interstellar dust could transport life from star to star
The theory of Panspermia states that life exists through the cosmos, and is distributed between planets, stars and even galaxies by asteroids, comets, meteors and planetoids. In this respect, life began on Earth about 4 billion years ago after microorganisms hitching a ride on space rocks landed on the surface. Over the years, considerable research has been devoted towards demonstrating that the various aspects of this theory work.
The internal ocean of Saturn’s moon Enceladus could be old enough to have evolved life, finds study
We recently bade farewell to the Cassini spacecraft, which after 13 years of faithfully orbiting Saturn and its moons was directed to plunge into the giant planet’s atmosphere. The reason for the “grand finale” was to guard against the possibility that Cassini might crash into one of Saturn’s moons – in particular Enceladus.
Dinosaurs could have avoided mass extinction if the killer asteroid had landed almost anywhere else
The decline of the dinosaurs, the rise of mammals and, ultimately, the origins of humans were even more unlikely than previously thought, according to new research. The huge asteroid collision that sparked this change in the Earth’s diversity was already a highly improbable roll of the celestial dice. But a new study suggests the mass extinction that followed it was only so severe because of where the asteroid struck.
Enceladus had an internal ocean for billions of years
When the Cassini mission arrived in the Saturn system in 2004, it discovered something rather unexpected in Enceladus’ southern hemisphere. From hundreds of fissures located in the polar region, plumes of water and organic molecules were spotted periodically spewing forth. This was the first indication that Saturn’s moon may have an interior ocean caused by hydrothermal activity near the core-mantle boundary.
Are red skies at night a shepherd’s delight? An astronomer’s view
Humans have always used simple observations of nature to try to understand our complex environment and even the wider cosmos. One such example is: “Red sky at night, shepherd’s delight” and “Red sky at morning, shepherd’s warning”. These sayings – which date back to the Bible (Matthew 16:2b–3) – suggest that a particularly red sunset means clear weather is coming and a particularly red sunrise means it’s going to be bad weather or possibly a stormy day.
What is space? The 300-year-old philosophical battle that is still raging today
Mountains. Whales. The distant stars. All these things exist in space, and so do we. Our bodies take up a certain amount of space. When we walk to work, we are moving through space. But what is space? Is it even an actual, physical entity? In 1717, a battle was waged over this question. Exactly 300 years later, it continues.
Our Universe is too vast for even the most imaginative sci-fi
As an astrophysicist, I am always struck by the fact that even the wildest science-fiction stories tend to be distinctly human in character. No matter how exotic the locale or how unusual the scientific concepts, most science fiction ends up being about quintessentially human (or human-like) interactions, problems, foibles and challenges.
To find aliens, we must think of life as we don’t know it
From blob-like jellyfish to rock-like lichens, our planet teems with such diversity of life that it is difficult to recognise some organisms as even being alive. That complexity hints at the challenge of searching for life as we don’t know it – the alien biology that might have taken hold on other planets, where conditions could be unlike anything we’ve seen before.
Cosmic alchemy: Colliding neutron stars show us how the universe creates gold
For thousands of years, humans have searched for a way to turn matter into gold. Ancient alchemists considered this precious metal to be the highest form of matter. As human knowledge advanced, the mystical aspects of alchemy gave way to the sciences we know today. And yet, with all our advances in science and technology, the origin story of gold remained unknown. Until now.
Dark matter: The mystery substance physics still can’t identify that makes up the majority of our universe
How far beyond Earth will we go to safeguard our species?
Revealing Galactic Secrets
Countless galaxies vie for attention in this monster image of the Fornax Galaxy Cluster, some appearing only as pinpricks of light while others dominate the foreground. One of these is the lenticular galaxy NGC 1316. The turbulent past of this much-studied galaxy has left it with a delicate structure of loops, arcs and rings that astronomers have now imaged in greater detail than ever before with the VLT Survey Telescope. This astonishingly deep image also reveals a myriad of dim objects along with faint intracluster light.
Debris disk around stars could point the way to giant exoplanets
According to current estimates, there could be as many as 100 billion planets in the Milky Way Galaxy alone. Unfortunately, finding evidence of these planets is tough, time-consuming work. For the most part, astronomers are forced to rely on indirect methods that measure dips in a star’s brightness (the Transit Method) of Doppler measurements of the star’s own motion (the Radial Velocity Method).
Monster volcanoes on Mars: how space rocks are helping us solve their mysteries
Mars famously has the largest volcanoes known to science. The largest is Olympus Mons, pictured above, which towers 22km above the surrounding plains – over two and a half times taller than Mount Everest. This extinct volcano is 640km wide even at its narrowest point, greater than the distance between London and Glasgow, or Los Angeles and San Francisco. And Olympus Mons isn’t alone in the Earth-beating stakes – three other Martian volcanoes are more than 10km high.
Bursting with Starbirth
This oddly-shaped galactic spectacle is bursting with brand new stars. The pink fireworks in this image taken with the NASA/ESA Hubble Space Telescope are regions of intense star formation, triggered by a cosmic-scale collision. The huge galaxy in this image, NGC 4490, has a smaller galaxy in its gravitational grip and is feeling the strain.