A weekend of science, part 1

"Introduction to Rocket Science" was organised by the British Interplanetary Society (the world's oldest space advocacy organisation) and held at the Royal Institution; the library was used as one of the lunch rooms -

What a great day, with 14 sessions about space, satellites, earth observation, the future - and very little of that off-putting mathemtical stuff, much more about people's personal stories and involvement.

Rocket-launch ties and starry waistcoats were in evidence -

 as well as NASA teeshirts in the audience (and one little girl wore her astronaut costume).

The first big surprise was a gorgeous model airplane, used to demonstrate the principles of flight. During his 50 years as an aerospace engineer, Bob also made model planes of his own design. The one he's holding weighs all of 2 grams -

so not much energy is needed to get it airborne -

Before lunch we learned how to build a spacecraft - or rather, about what's involved in a team building a spacecraft; found out how many satellites it takes to provide worldwide coverage (Oneweb will use about 800 to provide global internet coverage); saw a satellite image that just about showed a person moving - and voted on whether to send humans or robots into space (opinion was split). That and more before lunch.

After lunch, a quiz chaired by Stuart Eves got us to our feet and putting hands on heads or bums for answers "higher" or "lower" for answers to questions like: "The moon is moving away from earth at 4cm a year. Since Neil Armstrong walked on it, has it moved more or less than his height (180cm)." How stressful is it to do mental arithmetic in public! Get it wrong and you have to sit down, eliminated.

I was one of five who lasted to the penultimate round - last woman standing. The moons of Jupiter were my downfall - more than 60, or fewer?

Involving the under-12s - Mars Rover engineer Abbie Hutty gave them balls of various sizes for Earth, Moon, Mars - and a speck of dust for a satellite - and arranged them by relative distance - the satellite 50cm from the centre of the football, the moon 5 metres away ... and Mars (the girl in the astronaut overall) would be in Hyde Park -

Next up, exoplanets and aliens - the Drake equation estimates that about 20,000 technological civilisations have existed. Wow.

It's always a good idea to have a Real Live Astronaut in attendance - Cady Coleman told us about her life in space - 159 days in total - and back on earth -

Not many people get to see this happening in front of their eyes

Quote of the day: "Things change when you have a different way of looking at them." What would it be like to spend time off-earth?

Why explore space, though? Two reasons: to get above the effects of the atmosphere; and, to go to "interesting places" - such as sending probes to Venus found that under its clouds the air pressure is 90 times that on Earth, and the temperature is about 700 degrees. Not somewhere for humans to live, then. And Saturn's rings are "a natural laboratory for gravity".

The James Webb Space Telescope is one of the next big things (remember the excitement of Hubble, launched 27 years ago?). The JWST has an enormous sunshield and a huge mirror made of hexagonal mirrors that have a grid of tiny holes, allowing them to deform slightly (interesting; but I've forgotten why this is necessary). Due to launch in 2018, it will be looking at "old light" and sending 235 gigabytes of information back to Earth each day, ie lots and lots and lots of data.

Another next big thing, at the other end of the size spectrum, is cubesats, made possible by shrinking technology. They measure 10x10x11cm and the units can be linked into arrays. All those little things whizzing round the planet - surely there are collisions?

At the end of a long day, the final talk was titled "We're doomed!" and when you're tired, that's not what you want to hear. But the message is more hopeful - yes, one day a big "near earth body" will hit us, and we don't know when, but bear in mind that 100-150 tonnes of stuff from space (mostly dust) hits Earth every day, and that there's an inverse relationship between the size of the object and the frequency of hits.

The day ended with a bang of a different sort: a giant participatory "experiment" in the famous Faraday Lecture Theatre, where, amid glorious pandemonium, the balloons we'd written our names on and blown up went whizzing round, hoping to land on the prizes laid out on the floor -

I got lucky! -

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