Ethiopia tends to conjure images of sprawling dusty deserts, bustling streets in Addis Ababa or the precipitous cliffs of the Simien Mountains – possibly with a distance runner bounding along in the background. Yet the country is also one of the most volcanically active on Earth, thanks to Africa’s Great Rift Valley, which runs right through its heart.
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.
You might be in a medical experiment and not even know it
In the long view, modern history is the story of increasing rights of control over your body – for instance, in matters of reproduction, sex, where you live and whom you marry. Medical experimentation is supposed to be following the same historical trend – increasing rights of autonomy for those whose bodies are used for research.
How quantum materials may soon make Star Trek technology reality
If you think technologies from Star Trek seem far-fetched, think again. Many of the devices from the acclaimed television series are slowly becoming a reality. While we may not be teleporting people from starships to a planet’s surface anytime soon, we are getting closer to developing other tools essential for future space travel endeavours.
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.
Five claims about coconut oil debunked
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.
Human evolution is more a muddy delta than a branching tree
Until recently, anthropologists drew the human family tree in the same way that my 10-year-old son solves a maze. He finds it much easier to work from the end to the beginning, because blind alleys lead with depressing sameness away from the start. In just this way, scientists once traced our own lineage from the present into the past, moving backward through a thicket of fossil relatives, each perched upon its own special branch to extinction.
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.
Having a backup plan might be the very reason you failed
The great mystery of mathematics is its lack of mystery
In one sense, there’s less mystery in mathematics than there is in any other human endeavour. In math, we can really understand things, in a deeper way than we ever understand anything else. (When I was younger, I used to reassure myself during suspense movies by silently reciting the proof of some theorem: here, at least, was a certainty that the movie couldn’t touch.) So how is it that many people, notably including mathematicians, feel that there’s something ‘mysterious’ about this least mysterious of subjects? What do they mean?
Dark matter: The mystery substance physics still can’t identify that makes up the majority of our universe
I’ve always wondered: why do our computing devices seem to slow down?
How far beyond Earth will we go to safeguard our species?
Why we must keep the fires of the magical firefly burning
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.
Final decision? Why the brain keeps on changing its mind
Benjamin Franklin once quipped: ‘There are three things extremely hard: steel, a diamond, and to know oneself.’ Every decision we make, from pinpointing the source of a faint sound to choosing a new job, comes with a degree of confidence that we have made the right call. If confidence is sufficiently low, we might change our minds and reverse our decision. Now scientists are using these choice reversals to study the first inklings of self-knowledge. Changes of mind, it turns out, reflect a precisely tuned process for monitoring our stream of thoughts.
How we learn to read another’s mind by looking into their eye
How the rainbow illuminates the enduring mystery of physics
This summer I went on a family holiday to Cornwall, on the Helford River. The peninsula south of the river is, rather wonderfully, called The Lizard. Standing on its cliffs, you are at the southernmost point of mainland Britain. North of the river is the port of Falmouth, from where packet-ships kept the mail services of the British Empire running until 1851.