Maths confirms Pluto’s not a planet
A new formula seeks to define a planet. As Rick Lovett reports, 99% of the exoplanets found so far qualify, but Pluto does not.
Did a missing trace element trigger mass extinctions?
Selenium shortages coincide with species collapse.
Dark matter uncovered
Most of the matter in the Universe consists of stuff we can’t see. It is dubbed “dark matter” and we know it must be out there. Without dark matter rapidly spinning galaxies (such as those circled, above) would not have sufficient gravitational glue to hold their stars and gas clouds together. These elements would fly off into space instead, like rain drops on a spinning bicycle wheel. What might this ghostly, galaxy glue be made of? Nobody knows. But in 2006 astronomers got a new clue.
A new way of defining temperature?
Atoms wriggle – they can’t help themselves. And the warmer they are, the faster they writhe. By using lasers to measure how fast atoms of the element caesium zip around a vacuum chamber, Australian scientists have shown they can calculate the sample’s temperature. The super-accurate technique could be adopted as the basis of a new definition for the standard unit of temperature, the Kelvin.
Invisibility becomes reality?
As far back as Plato people imagined the power of invisibility. Now the fantasy is being made real.
What does an electron cloud really look like?
A new microscopy technique allows us to see the glue that holds molecules together.
Ghost traps: the hunt for dark matter
We have no idea what most of the matter in the Universe is made of. Are we finally closing in on dark matter?
Why the building blocks in our cells turned to the left
Amino acids could have become “left-handed” on a journey through space. Viviane Richter explains.
Ancient forest microbes live 2.5 kilometres under the sea
Scientists drilling off the coast of Japan have awoken an ancient creature from its long slumber. But don’t worry – they did not find Godzilla. They revived a community of microbes, trapped beneath the ground for around 20 million years.