My kids saw something on the telly recently about how people are booking the first holidays in space. There was an interview with a rather well-off pensioner who is shelling out hundreds of thousands of pounds to be suspended several miles above Earth for the weekend, courtesy of Virgin Galactic, and, predictably, it has given my little treasures some big ideas. They've decided that if he can do it, so can they - and they've been pestering me to get booking ever since. I've started saving my pennies.
In the meantime, though, there are still some places on our own planet that might just be worth a visit. You don't have to get into a rocket to find other-worldly landscapes.
Hop over the Irish sea and head for County Antrim, at the northernmost point of Ireland, for example, and you'll find the amazing Giant's Causeway, 40,000 stone pillars sticking out of the sea which were created by intense volcanic activity 60 million years ago (no, Stanley, I wasn't alive then). The surrounding chalk and basalt landscape has an almost lunar feel - it certainly doesn't look like anything else on Earth - which might be exactly what the kids are after. (Just dig out their Buzz Lightyear dressing-up gear and give them a couple of hours' imaginative play. Richard Branson, eat your heart out.) And for some much-needed creature comforts, post-mission, stay at the family friendly Bushmills Inn Hotel (028-2073 3000; bushmillsinn.com).
Further afield, how about a volcanic island to get your mini-astronauts into training for Mars? Last year, I discovered that a hike up a smouldering volcano was one of the few ways to get my kids to be quiet. While on holiday in the Canaries, we visited the Timanfaya Volcano Park, on Lanzarote. The kids were particularly impressed by the volcano-top demonstrations: they watched boiling water shoot 100ft in the air as a park ranger created a man-made geyser. Better still, they ate pizzas cooked in the depths of a sleeping volcano in a hidden restaurant built into the rocks.
While you're in the Canaries, take a trip to Fuerteventura's Dunas de Corralejo National Park, too, where you'll find scenery that "looks like something out of Dr Who". The miles of white sand dunes and volcanic rock provided hours of pleasure for my kids. Go it alone with James Villas (08700 505058; james villas.co.uk), or, if you fancy having it all laid on for you, follow our example and stay in the Oasis Papagayo with Thomson. The kids loved everything about this place: the food, entertainment and excursions (0870-165 0079; thomson.co.uk).
For volcanic adventures further afield, how about Costa Rica, known for its family-friendliness with stunning landscapes to boot: check out The Adventure Company's (0845-450 5316; adventure company.co.uk) Natural Magic Family Holiday. It takes in volcanoes galore as well as offering lots of opportunities to let off some steam in its natural hot springs. Sounds out of this world to me - and with any luck it'll put a stop to my kids asking for the moon for a while...
Katy's top tip
Take your brood for an Italian volcanic adventure on the little island of Salina. Explore black -sand beaches and watch natural firework displays courtesy of Stromboli from your own private terrace at the Hotel Signum (020-7377 8518; thinksicily.com) </p>