theoretically ...

NASA's second rocket to Mars, the Mars Pathfinder, should have taken off at 6.09 GMT this morning - assuming all went well. This was the only time NASA had for a launch today, though there is a 24-day "launch window" lasting until 31 December. Pathfinder is due to arrive on Mars on 4 July next year. It will investigate the Martian atmosphere and surface weather, and use a small six-wheeled rover to investigate the terrain around the spacecraft, and the geology and elemental composition of rocks and soil there.

The relaunch of the Cluster project, lost when Ariane 5 blew up, is all systems go - providing national governments come up with the funding. On this page last week we forecast that the European Space Agency would probably give Phoenix the go-ahead. Now it needs the Department of Trade and Industry to stump up pounds 7m over four years to refit the experiments for launch. Watch this space.

Don't get nervous - but anxiety seems to have a genetic component. A report in last week's Science magazine found that levels of neuroticism correlated with two different variants of a gene that encodes a protein critically involved in controlling levels of the neurotransmitter, serotonin. An investigation of 505 people found that this genetic variation accounted for about 4 per cent of variation in anxiety-related traits. A small difference, but the sort that could nag away at the back of your mind.

Odd, isn't it, how there are more organic compounds with an even number of carbon atoms than an odd number? That's the observation by a five-strong international team. And they ask: could that fact mean something? In the latest Nature, they report how a database of nearly 7 million organic compounds shows that, in general, even numbers of carbon atoms are significantly more common than the adjacent odd numbers. "Could there be some underlying parity rule that is yet to be discovered?" they ask. Any answers?

A mauve carnation can be yours. Florigene, an Australian biotechnology company, has spent $A25 million (about pounds 12 million) and a decade of research to produce one, using genetic engineering. It is the first step towards a range of genetically engineered blue flowers - including the long sought- after blue rose. The company isolated the gene responsible for blue flower pigmentation in 1991. The new flowers will cost about twice as much as normal carnations, but no doubt smell as sweet.

The Internet is bad for science, suggest two researchers at MIT. They point out in Science that it tends to produce specialists who don't stray out of their own areas. "If information technology helps an algebraic topologist spend more time interacting with colleagues globally, what happens to his or her interactions with the computer scientist, the biologist or the graduate student down the hall?" they ask - pointing out that the theory dinosaurs were wiped out by a meteorite strike came from the collaboration of a geologist and physicist.