I was a guest on The Guardian's science weekly podcast today, talking to Alok Jha about the NASA and ESA agreement to collaborate on the Orion space missions. Previously these had been exclusively NASA missions, designed to send American astronauts to deep space.

Now, however, ESA are providing hardware for at least the first mission or two, meaning that this is now an international endeavour.

The interview is a follow-up to my article on how NASA and ESA are planning to collaborate on the Orion missions to deep space. It was published on 16 January and can be read here.

You can listen to the podcast here.  As well as my Orion discussion, there is also an interesting discussion about the Higgs boson.

I have the cover story on New Scientist this week. Provocatively titled Sacrificing Einstein: Why we must let go of a foundation of relativity, it discusses the modern attempts to leap beyond Einstein's physics and find a deeper theory of gravity.

"Our hopes of finding a theory of everything depend on upsetting a balance that Einstein cherished

COINCIDENCE is not generally something scientists have much truck with. If two things are genuinely unrelated, there is little further of interest to be said. If the coincidence keeps turning up, however, there must be some deeper underlying link. Then it is the job of science to tease out what it is and so explain why there was no coincidence in the first place.

That makes it rather odd that a large chunk of modern physics is precariously balanced on a whopping coincidence.

This coincidence is essential to the way we view and define mass. It is so fundamental to the world's workings that most of us encounter its consequences every day without giving them another thought. Yet it has vexed some of the best minds in physics for centuries. Galileo and Newton grappled with it, and ended up just accepting it, rather than understanding it. Einstein went one better: he declared it a principle of nature. He went on to use this "equivalence principle" as the fundament of his general theory of relativity, still our best stab at explaining the mysterious force of gravity.

But there is a problem. If we want to find some bigger, better theory that can unify gravity with the other forces that dictate the world's workings, the equivalence principle cannot stay. We must either unmask this coincidence - or radically rethink how physics can progress from here.

You can read the full article here but you need to sign in.

It is with the greatest of pleasure that I can unveil the front cover of The Day Without Yesterday. This is the third and final novel in The Sky’s Dark Labyrinth trilogy. It tells the dramatic story of Albert Einstein and Georges Lemaître, the two men who shaped our modern understanding of cosmology.

The Day Without Yesterday will be available in February. You can order the book online from Waterstones, amazon, and The Book Depository.

The book will also be available in your local bookshop. For those within striking distance of London, you can be the first to own a signed copy as I will be at the European Astrofest signing the very first copies of the books off the presses. Astrofest takes place on February 8-9 at Kensington Town Hall.

I have a new post over at my Across the Universe for The Guardian.

“The space agencies are about to reveal more about their collaboration to send astronauts beyond Earth's orbit. But will the Orion missions be inspirational enough for their critics?

It is now more than 40 years since a human ventured beyond Earth orbit. The last three astronauts to slip our world's gravitational tethers were those on Apollo 17. They crossed 385,000 kilometres of space to land on the moon and then returned to splashdown in the Pacific on 19 December 1972.

Since then, no human has been higher than about 600 kilometres above Earth's surface. Now it is time to reach out again. ...”

You can read the full story here.

I had the pleasure of being interviewed by Justin Trottier for The Star Spot podcast.

From their website:
“Dr. Stuart Clark joins Justin Trottier at The Star Spot to share his unique work dramatizing the great stories of science. Clark combines his background in astrophysical research with his career in science journalism and writing to author a trilogy of novels that focus on the lives of the great minds of astronomy, from the Trials of Galileo to the personality conflicts between Isaac Newton and Robert Hooke, to the discovery of the Big Bang by Einstein, Lemaitre and others. Clark also discusses his blog for The Guardian called Across the Universe, and shares his insights into teaching critical thinking and how to use the history of discovery to deepen the public appreciation and understanding of science.”

You can listen to the podcast here.