What will the sciences look like in 1997 and who will be the people to watch? Graham Lawton, in the final part of the series, spots the projects to watch

The new year will be one of celebration for particle physics. 1997 marks the centenary of the discovery that gave birth to the field, J. J. Thomson's announcement that he had isolated the first fundamental particle, the electron.

A century of research has equipped physics with a widely applicable theory of elementary particles. The so-called Standard Model is regarded as a successful theory, but it is clearly incomplete. One physicist calls it "disgustingly successful" because locating its weaknesses has proved so difficult. But over the next 12 months researchers could go some way to challenging the model's hegemony.

In the summer a new experiment will probe some of the theories clearest frailties - the solar neutrino problem. The sun is powered by nuclear reactions that produce enormous numbers of particles called neutrinos, some of which are propelled towards earth. Physicists can calculate how many neutrinos should reach the earth. But when they count them there never seem to be as many as expected.

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The reason for the missing neutrinos remains controversial. One idea is that during their journey the solar neutrinos change type and thus evade detection. If this is true it reveals a chink in the Standard Model. If solar neutrinos are changing form, they must have mass. But under the Standard Model neutrinos are massless and cannot change their form. The new experiment has been set up to look for altered solar neutrinos (see box).

Researchers at CERN, the European Laboratory for Particle Physics, will also be using 1997 to probe the Standard Model. The electron-positron collider experiments will continue to look for a long sought-after particle called the Higgs Boson, a central part of the model which explains the existence of mass. If they find it then CERN staff can expect a few celebratory hangovers in 1997.

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Experiments at CERN could also open a new window on the big bang theory. By smashing lead nuclei together scientists are trying to create a state of matter that is thought to have existed in the early universe. Next year should see initial results that give indications whether or not this stuff, called a quark-gluon plasma, can exist.

1997 also promises to be an exciting year for space science. Astronomers will be upgrading the Hubble Space Telescope and continuing to work on Martian meteorites, which should give us a clearer view of the possibility of extra terrestrial life.

1997 also sees the launch of a major new space mission. If everything goes to plan then the final stage of the exploration of the outer solar system will begin on October 6 with the launch of the Cassini-Huygens mission to Saturn. The ship will take seven years to reach its destination via gravitational assists from Venus (twice), the Earth and Jupiter. The main craft, Cassini, is the largest and most sophisticated ever sent to the outer planets (see box). Thanks to Nasa's economy drive we may never see its like again.