I was going to write more, but I’ve decided to let the image speak for itself.

• Scorecard co-editor and Brookings Senior Fellow Justin Vaïsse!
• Former head of UN peacekeeping and foreign affairs guru Jean-Marie Guéhenno!!
• James Traub, superstar essayist for the New York Times and Foreign Policy!!!
• Me.

This is an open event.  Fuller details and an address for RSVPs are available here.

Playboy magazine is not the most obvious choice for those preoccupied with nuclear proliferation. Yet, Joshua Pollock’s article on “The Secret Treachery of A.Q. Khan” in the January/February 2012 issue has proved to be as titillating as the all-revealing photos that made the publication infamous.

The article, written in the whodunit oeuvre, uncovers that in addition to the three known customers of the Khan network—Iran, North Korea and Libya— there was a fourth hitherto unknown customer and reveals the “last country on the list: India, Pakistan’s foe.”

It’s worth reading the whole column.  But I want to know whether the publication of Pollock’s piece resulted in a big rise of sales of Playboy in news agents around the International Atomic Energy Agency’s Vienna headquarters.  Was some aspiring Hans Blix sent out in a grubby mack to purchase copies of the top shelf magazine for his superiors?   Did IAEA Director General Yukiya Amano have to flick through pages of poorly-clad minor celebrities to find the article (curiously, there is no mention of it in his “Director’s Corner”)?  Is the Bulletin of Atomic Scientists, which has a slightly stronger pedigree on nuclear issues, going to change its approach to illustrations now?

These are all puerile questions.  But you know you want them answered.

As it turns out, though, Sunday’s solar flare was just a warm-up. Another even larger one – scoring 9 on a strength scale that runs to 10 – set off towards us at about 4am GMT yesterday, which means it will be arriving in about 4 hours’ time (2pm GMT on 24 January).  The image below is from NASA’s Solar Dynamics Observatory; see also this movie from SOHO, NASA’s Solar and Heliospheric Observatory.

Does this mean we’re in for a Carrington Event? Doesn’t look like it - 95% of the CME is going to miss us, so we’ll only catch the edge. Had it hit us square on, we’d be looking at very substantial disruption to internet, GPS and telecoms. But if you live in a northern latitude and you have a clear evening, then certainly worth keeping an eye on the sky – could be pretty spectacular.

From XKCD, via Tim Harford.

A new index published in the journal Astrobiology scores planetary bodies on their suitability for life. As the Economist explains,

Tipping its hat to the possibility that aliens could have dramatically different biochemistry from earthlings, the index confines itself to measuring big-picture factors such as the presence of a solid surface, the average surface temperature, the strength of a planet’s magnetosphere (which helps shield it from cosmic radiation) and the like.

Unsurprisingly, Earth comes top of the list. Interestingly, though, Titan, a Saturnian moon covered in hydrocarbon lakes, takes the second spot in our solar system, ahead of Mars. And with a decent score too. Time to start packing?

It’s so hard to know which global threat to worry about most these days. Global warming? Weaponized bird flu? WMD? Well, now you can add the Death Star to your list. Viewers of Star Wars will of course recall the planet-sized spaceship that could blow up planets, but they may have dismissed it as entertainment.  The fools…

Such an act of destruction would seem impossible to us–it seemed so to many of the movie’s characters until it happened. But perhaps not, say three students at the University of Leicester in England who last year published a study on the subject in their university’s undergraduate physics and astronomy journal.

The study’s authors start off by making some simple assumptions: The planet being fired upon doesn’t have some sort of protection, like a shield generator. And it’s about the size of Earth but solid through and through (Earth isn’t solid, but the planet’s layers would have significantly complicated the math here). They then calculate the planet’s gravitational binding energy, which is the amount of energy required to pull apart an object. Using the mass and radius of the planet, they calculate that destruction of the object would require 2.25 x 10³² joules. (One joule is equal to the amount of energy required to lift an apple one meter. 10³² joules is a lot of apples.)

The energy output of the Death Star isn’t given directly in the movie, but the space station was said to have had a “hypermatter” reactor that had the energy output of several main-sequence stars. For an example of a main-sequence star, the authors look to the Sun, which puts out 3 x 10²⁶ joules per second, and they conclude that the Death Star could “easily afford to output [the energy required for an Earth-like planet's destruction] due to to its tremendous power source.”

Fantastic.  The only good news is that the Death Star probably couldn’t take out Jupiter without self-destructing.  Perhaps the need to get to larger planet explains China’s recent burst of enthusiasm for manned space flight?

[H/t: Vanessa Parra.]