Extending our reach in 2000

BBC News Online science editor Dr David Whitehouse takes a personal look back at 2000

The past year has been a dramatic one in science. Particles, genes, cells and planets all gave up a few of their secrets and pointed the direction research will take in the first decade of the new millennium.

This year, the ISS received its first residents

In a sense, the future began in 2000 with the completed "first draft" of the human genome sequence and the first crew installed on the International Space Station.

They marked the beginning of real power over our bodies and our first colony in space.

With these efforts, humankind's reach extended outward to the cosmos and inward to the universe that is ourselves.

Living things

Now that scientists have read virtually all our DNA, they are looking beyond this first proof of the book of life to try to understand what all our genes mean - functional genomics researchers call it.

With these efforts, humankind's reach extended outward to the cosmos and inward to the universe that is ourselves

The detailed genetic comparison between species will be a very rewarding area, showing just how related are all lifeforms on our planet.

We will see clearly how even minor differences in the genetic code can determine quite big differences in the nature of living things.

Sharing and analysing the reams of genetic information in this research will require new ways of representing data. A version of Napster, the person-to-person MP3 music sharing program, is already being adapted to share DNA sequence data.

Cell engineering

Stem cells generated much excitement and controversy throughout the year. Stem calls can - in principle - develop into any type of body tissue and so have enormous potential in medicine, replacing damaged tissues and some day even organs.

Human chromosomes: We are just beginning the journey into ourselves

The UK's politicians are currently debating whether to give the nation's scientists permission to use embryos to harvest what many believe to be the most powerful of these "master" cells.

But opponents of the use of embryonic stem cells believe researchers can do the same science using cells taken from adults or umbilical cords, and they point to some promising early results.

However, it seems clear that although in the long-term adult stem cells will prove extremely adaptable and useful, a fundamental understanding of cell engineering will only come from the knowledge gained in the research done on embryonic cells.

Little Earth

Knowledge of the Universe without has also expanded rapidly during 2000. Data from distant galaxies are providing evidence that the cosmos is expanding - and at an accelerating rate. This is probably the last outcome astronomers would have expected just a few years ago.

The more we find out about the Red Planet in its early history, the more it reminds us of the Earth

Yet more worlds found orbiting other stars in 2000 tell us, without doubt, that the Universe is teeming with planets. But the planets so far discovered are gas giants - the techniques required to detect Earth-sized planets do not exist at the moment.

This will require new instruments to be positioned in space. If there are Earths out there, we may have a picture of one by 2010. It will be just a pale dot and astronomers will be debating what can be deduced from an analysis of the planet's light.

Closer to home, we are discovering swarms of icy bodies residing in the cold outer-reaches of the Solar System. These leftovers from planetary formation are unchanged for billions of years, preserving clues to the planets' birth and recording galactic history since then.

How like us?

And what can be said about Mars that is not rapidly superseded by something more amazing? The more we find out about the Red Planet in its early history, the more it reminds us of the Earth; a world that was warm and wet.

Mars: Pictures of the planet's surface continue to astonish researchers

Biogeologists are realising just how swiftly life arose on the primitive Earth; within a few tens of millions of years, where the conditions allowed. If it happened on our planet so fast, could it not have happened on Mars as well?

Towards the end of the year, the team of scientists that in 1996 claimed to have found evidence of life in a Martian meteorite returned with an impressive research paper suggesting that magnetic grains in the rock were identical to features produced by bacteria on Earth.

The debate about life on Mars is wide open.