This year has been the year of Mars. The red planet is closer to Earth now than it has been for 60,000 years, and on Christmas Day, the UK's Beagle 2, an unmanned spacecraft about the size of a backyard barbecue, will land on its surface. With 11 sophisticated instruments capable of detecting traces of life in subsurface rocks and Mars's atmosphere, the craft will use solar power to transmit key data back to Earth. Scientists on Professor Colin Pillinger's team at the Open University at Milton Keynes may be able, at last, to unravel the mystery of life beyond the terrestrial.
One who will be glued to the news as it unfolds is Monica Grady. A world authority on extraterrestrial geology, Dr Grady was for a decade on Professor Pillinger's team and is married to his second-in-command, Dr Ian Wright, who played a key role in devising Beagle 2's experiments. This year she is giving the Royal Institution's Christmas lectures, on the theme of voyages in space and time.
"My interest came from going out into the Yorkshire Dales and seeing geology there in the landscape, looking up and seeing the stars," says Dr Grady. Head of the petrology and meteorites division at the Natural History Museum, London, and honorary reader in geological sciences at University College, London, Dr Grady is so keyed into her chosen field that she has even had an asteroid (4731 Monicagrady) named after her. The study of carbon and nitrogen in meteorites sounds dryly scientific, but in her enthusiastic hands it reveals itself as astrobiology: the study of what, if any, life there may be beyond our planet Earth, as evidenced by clouds of dust and stones that rain down on us every minute from the cosmos.
The eldest of eight children born to a zoologist mother and an inspiring, classics teacher father, the young Monica Grady enjoyed school, particularly geography lessons, at her girls' grammar in Leeds. But it was rambles with an older family friend that set the seal on her life's passions - the sky and the land. She fears, she says, for modern urban children, who can scarcely see the stars for city light pollution. "I like to know, when I come home late at night and look up, that Orion is there looking out for us. It's a shame that when I go to schools, so many children don't know what or where Orion is."
This year, as well as Mars being at its closest to us for 60,000 years, there has been a European space probe - Mars Express, which carries the Beagle 2 lander, and much public interest in space and stars. But, she says: "We need to tell people that the sky is interesting all the time. You can see meteors, not just when there are big showers when you're on holiday in August. If you watch the sky for an hour you will see one or two. It's beautiful, much more beautiful than floodlit buildings. But floodlighting blocks our view of the stars."
Mary McCormack, her inspiring geography teacher, was no starry-eyed sweety.
She was, says Dr Grady, "often sarcastic, and didn't suffer fools gladly.
But I found her lessons entertaining, she had a knack of knowing when she was in tune with me - which wasn't in the human geography lessons."
Still, in the 1970s it was difficult to take geography A-level as well as maths and physics, even if you wanted, as Monica Grady did, to be a meteorologist. So geography remained a hobby, while chemistry, "which I came to absolutely love", moved centre stage. At Durham, where she studied chemistry with geology, she took some time to find her academic feet.
It was in 1979, her final year, she remembers, that she realised what she wanted to do. The joint honours course required two pieces of research, and, off mapping by herself in Wales ("they'd never allow that nowadays") and back writing up her results and seeing patterns emerge, she realised that this kind of hard work with blazes of insight was what she most enjoyed. Off to Cambridge to do a PhD on meteorites, she met her future husband on her first day, abandoning the boyfriend with whom she had come to the university.
What drew her to a life of research? "I was always retiring at school, but I was conscientious," says this engaging, forthright woman, laughing at the suggestion that she is "married to Mars". "I'm married to Ian," she points out, though adding that they do talk about science and work and the big questions all the time, as well as their son, Jack. "I just drifted," she says now, "I followed my interests. If you do what interests you, you'll work hard at it."
Dr Ian Wright is second in the team running Beagle 2, under the leadership of Professor Pillinger at the Open University. Dr Grady, too, had worked with Professor Pillinger happily for many years, following him when he moved to the Open University in 1983 to set up the Planetary and Space Science Institute, until, in 1991, the "perfect" job came up at the Natural History Museum. "I have blossomed here," she declares.
At the time, the move entailed a tough decision, as Jack was only a baby.
They decided to have only one child, so the long commute from Milton Keynes would not be too stressful on family life, a decision, Dr Grady says, that has meant Ian does more than his share of the childcare and organisation, as he works nearer. "We've not regretted it."
She says: "As a Catholic, I thought about it a lot. There never is a right time to have a child." Jack, who goes to the independent Bedford school, shows little signs of wanting to follow in his parents' scientific footsteps, though "he is good at science. With us at home, he can't help it." History is more his field, and history - of the largest kind - is one of the themes of this year's lectures.
Dr Grady speaks with deep enjoyment of her life. The commute is tiring, but, she says: "You can sleep on the train, read on the train.
Intellectually, this job has allowed me to pursue all my interests. It was my boss who encouraged me to develop teaching packages, charts, exhibitions, to use the huge instrumental resources we have here, to reach out and communicate the fascinations of science, to teach post-doctorally.
To apply for these lectures and get them was the icing on the cake." The cake consists of Mars and Martian meteorites, stars and the dust around them, what we can learn from telescopes and microscopes, how planets are formed and whether there is evidence for life beyond Earth.
Most fundamentally, she says, she wants her target audience of 12 to 15-year-olds to know that there is "still so much to be done in science, so much unknown about the universe, to come and join in the adventure of learning". If Tony Blair wants big questions, she says laughing, "I've got some really big questions."
Royal Institution of Great Britain: www.rigb.org. Beagle: from Darwin's epic voyage to the British mission to Mars, by Colin Pillinger (Faber and Faber, pound;14.99). Search for Life by Monica Grady (Natural History Museum, pound;9.95)
VOYAGES IN SPACE AND TIME: THE CHRISTMAS LECTURES
This year's lectures at the Royal Institution in London will be broadcast on Channel 4, including a live transmission on December 29, as follows:
Sunday December 28, 1.55pm Blast Off
The accepted theory of the formation of the universe from a Big Bang still leaves many questions unanswered. Calculations of the mass of material in the universe show that the billions of stars and tonnes of dust we can see with our eyes and instruments account for only three per cent of the whole.
Wimps (weakly interacting massive particles) can pass through the holes in atoms leaving no trace, and account for a further 20 per cent or so. But 75 per cent can only be accounted for by postulating "dark matter", a kind of negative, unseen mass and energy that we have no way of analysing. Einstein called this force, which pulls everything apart with huge speed, the "cosmological constant". He thought he had been mistaken, but scientists now believe he was right.
Monday December 29, 12.05pm Live from Mars
This is timed to coincide with early data from the landing of Beagle 2 on Mars on Christmas Day. Why is our nearest neighbour so interesting? Could we land there? Could we live there? What adaptations would life on this arid ball need? As Beagle 2's instruments grind up rocks from above and below the surface and analyse them, looking for specific carbon ranges which could denote past bacterial activity, what does this mean for our understanding of the universe? Are we alone? If we are, was the universe made for us? Or not? If we are not, who else is out there?
Tuesday December 30, 12.05pm Planet patrol
Who or what are our nearest neighbours in space? How are they like us? What do we know of their satellites, atmospheres? What would it be like to live and work in space?
Wednesday December 31, 12.05pm Collision course
How space interacts with earth. Every year 60,000 tonnes of matter falls on the earth, mostly as dust. Half a ton falls on London in an hour: there are plans afoot to show this in the Royal Institution with glitter, but Dr Grady says: "I'm only doing that if I don't have to hoover it up."
Thursday January 1 2004, 12.05pm Anybody out there?
Be it ET or interplanetary microbes, how we search for extra-terrestrial life, how we might travel, what new technologies are envisioned. What does Monica Grady think? "I just don't know. Sometimes I think it's too anthropic to think no, but I do wonder how we would react if some other life landed here." She brightens. "One day we will find out."
MEET THE NEIGHBOUR
Distance from Sun Mars: 142 million miles, Earth: 93 million miles
Speed in orbit Mars: 14.5 miles per second, Earth: 18.5 miles per second
Diameter Mars: 4,220 miles, Earth: 7,920 miles
Year Mars: 687 Earth days, Earth: 365.25 days
Day Mars: 24 hours 37minutes, Earth: 24 hours
Number of moons Mars: 2, Earth: 1
Average temperature Mars: - 65C Earth: 15C
Atmosphere Mars: carbon dioxide and water vapour, Earth: nitrogen, oxygen, carbon dioxide
Gravity Mars: 0.375 times Earth's
Journeys to Mars: the highlights
October 1960 First unmanned flyby (USSR)
November 1964 Mariner 4 (US). Flyby and return
1971 Mariner 9. Orbited Mars and returned
1974 Missions from USSR landed. Little data
1975 Viking (US). Orbited. Returned. Left lander
19967 Global Surveyor (US). Orbiter still sending back information
1997 Pathfinder (US). Lander and rover, now silent
1998 Nozumi orbiter (Japan). Now orbiting Sun
1999 Polar Lander (US). Lost after landing
2001 Mars Odyssey (US). Still orbiting
2003 Beagle 2. Touches down on Christmas Day after a six-month journey on Mars Express