The mass of the Earth is big enough that the gravitational force it creates can pull the hard shape of ice, rock and metal into a sphere.
NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center
Imagine the Earth pulling everything it is made up of, all of its mass, towards its centre. This happens evenly all over the Earth, causing it to take on a round shape.
Sofia Boutella plays the new Mummy.
The latest reboot of The Mummy is all you should expect from a Hollywood blockbuster on an ancient Egyptian curse. But what about the science?
Between the Earth and the moon: An artist’s rendering of a refueling depot for deep-space exploration.
Sung Wha Kang (RISD)
To get us to Mars and beyond, a team of students from around the world has a plan involving lunar rovers mining ice and a space station between the Earth and the moon.
Look ma, no gravity!
Every moment of life on our planet has had the force of gravity in the background. But the prospect of long-distance space travel means it's time to figure out what happens to our biology in its absence.
An artist’s impression of a Sun-like star close to a rapidly spinning supermassive black hole, with a mass of about 100 million times the mass of our Sun.
ESA/Hubble, ESO, M. Kornmesser
The discovery of a new black hole adds to our understanding of these celestial objects that fascinate in both fact and fiction.
There’s a lot we still don’t know about antimatter.
One of the great mysteries of the universe is why there is so much more matter than antimatter. Now a new experiment is helping us understand the nature of antimatter better than ever before.
Einstein’s theories are still not taught in school.
Einstein's theories of relativity underpin our understanding of the universe, yet they're not taught in high school. How can we change that?
Why weightlessness in space is about balancing forces rather than a lack of gravity.
There's a good reason you should care about the discovery of gravitational waves, even if you don't understand the science.
A team effort: Dr David Reitze, of the LIGO Laboratory at Caltech, shows the merging of two black holes that led to the detection of gravitational waves.
The discovery of gravitational waves involved a team of more than 1,000 scientists from across the globe, including Australia. So how does such an international collaboration work?
Massive bodies can send ripples through space time in the form of gravitational waves.
The long awaited discovery of gravitational waves has sent ripples through the scientific world. Here top experts respond to the historic announcement.
When two black holes collide, the resulting gravitational ripples can be felt across the cosmos.
The detection of gravitational waves is the final confirmation of Einstein's theory of general relativity, and opens up a new window into the cosmos.
Binary black holes come in a variety of forms, but they are all astounding.
NASA, ESA, and G. Bacon (STScI)
It takes something as stupendous as the merger between two black holes to generate detectable gravitational waves. Here's how such incredible cosmic objects form.
Two black holes collide.
University of Glasgow
It is the physics discovery of the century – even bigger than the Higgs Boson. Here's how it happened and what it means, by a key member of one of the lead teams
Struggle to understand modern physics? Blame Einstein.
Space, time and space-time: it's all relative.
It’s possible that had Einstein not conceived of general relativity, then we’d still be at a loss to explain gravity to this day.
Special relativity was inspired, but it took true genius to conceive of general relativity. Had Einstein not come up with it, it may have taken decades for us to figure it out.
You can feel the weight of an object on Earth because of its mass. But what is mass?
We talk about mass all the time but what is it that actually gives an object mass? And why do some things have mass and others have no mass at all?
A visualisation of gravitational waves emitted by two orbiting supermassive black holes.
A new study has failed to find evidence of gravitational waves, but that doesn't mean Einstein was wrong about their existence.
Astronaut Cady Coleman harvests one of our plants on Space Shuttle Columbia.
Plants on the International Space Station must figure out how to grow in a completely novel environment. Their adaptability hints at how they'll react to changes here on Earth – or in future space outposts.
How do we think about something we can’t see and don’t experience in our everyday lives, but seems to be pushing our universe apart ever faster?
NASA, ESA, G. Illingworth, D. Magee, and P. Oesch (University of California, Santa Cruz), R. Bouwens (Leiden University), and the HUDF09 Team
Einstein's theory of gravity says dark energy must be out there, accelerating the expansion of our universe. But what is it and how can we try to figure out more about it?