Kathy's Impact Diary

Production team

Day One

We are just so lucky! To be here in this crazy place of extreme weather and astonishing scenery. To be "forced" to do challenges that really are challenging and stretching, but enormous fun to do. To work with a bunch of people who are all so prepared to help and work together to try solve problems - and who are so creative. To have people available in such different areas of knowledge and skill too is just so interesting (as well as crucial for getting the challenges done!).

And now for this challenge we're being flown and helicoptered to Meteor Crater in Arizona. It's just too good to be true! It's a long journey, though, after an excruciatingly early start, and we don't have very long to make measurements.

Making the measurements isn't so easy either ... it's amazingly windy and very, very hot. And the terrain isn't exactly smooth and easy. In the lab, or the mine, it's so easy to decide what to do without realising how much harder the fieldwork will actually be.

At the end of the day I'm desperate to make more measurements to help us estimate the diameter of the crater. It's clearly not circular, so we need to try to estimate the diameter at several points to get a reasonable average.

Iain, the film crew and Kate all need to film Iain doing some geology, so I go off to do another measurement alone. It's a nightmare! The wind is so strong now that my cardboard table is almost wrenched away and keeps bending and breaking, the string is pulled like a kitestring and the tripods are blown over. It's all so ridiculously hard it becomes funny.

I eventually manage to do it all - with huge errors, I suspect - and sit and wait for the others to come pick me up. They take hours and hours, and the sun sets over Meteor Crater. It's a staggering view; all I can do is wait, breathe deeply, and enjoy the scenery - it feels a real privilege.

Production team

Day Two

Another excruciatingly early start. Back to the crater to finish off, with Iain doing his geological observations.

He's like a mountain goat - he leaps up near vertical rocks without a second thought. And he's so excited about geology. It's a scary thing to be driven by him, though - he's so interested in the rocks flashing by, you occasionally need to remind him about oncoming vehicles (as we veer into their lane).

Flew back direct to Lone Pine - right over the Grand Canyon and Death Valley. Hopelessly exciting! Grand Canyon (and Canyonlands beyond) is just vast. Amazing to see it from the air. And great to see Death Valley from above too ... trying to pick out the place Ellen did her epic walk in programme 3. And picking out 'Furnace Creek' and Zabriskie Point - amazing places I've visited before.

Day Three

In our absence, Mike B did a whole range of really careful experiments dropping balls into sand. It seems a kind of madness to be trying to scale up from ball-bearings in sand to a stonking great meteorite, but what else can we do?

We tried a bullet, which has huge speed but only a small mass, so it didn't help us as much as we hoped. The end of the challenge was the usual fight with daylight fading fast and last-minute traumas. We were so close with our estimate it was unbelievable - sheer fluke really, our errors were simply HUGE.

Jonathan and Ellen's telescope was a magical creation. The moon looked beautiful and its craters unbelievably clear. An amazing way to finish an amazing challenge!