Trinity College tomorrow launches International Heliophysical Year, an attempt to learn more about our nearest star, the Sun, writes Danielle Barron
Those with an interest in Chinese astrology will probably already know that 2007 is the Year of the Pig. What you may not know, however, is it also happens to be International Heliophysical Year (IHY).
Sponsored by the United Nations, European Space Agency and Nasa, IHY aims to bring together scientists to study the Sun and the entire solar system as a single massive science problem.
IHY will be officially launched tomorrow, which also happens to be the date of this year's Winter Solstice. It misses its usual arrival date on December 21st, occurring instead at 20 minutes past midnight.
"The heliosphere is an immense magnetic bubble that envelops the entire solar system. The Sun is at its centre, and it extends out to three times the distance of Pluto," explains Dr Peter Gallagher of the Astrophysics Research Group in the school of physics at Trinity College Dublin.
"What we are trying to do with IHY is bring together planetary scientists and solar scientists in order to study the fundamental physics, chemistry and even biology that determines how the whole solar system works as an entire unit," according to Gallagher
Astrophysicists have long known that events on the sun can affect geospace, including the Earth's climate. Even a fractional change in the energy output of the sun could play havoc with the stability of our weather systems, Gallagher says. He cites the example of the "Little Ice Age" that affected northern Europe during the 1600s, thought to have been caused by the dearth of sunspots on our nearest star around that time.
Our other neighbours in the heliosphere are not immune to such solar misbehaviour. "The Sun drives climate on our planet but it also drives climate on Mars, Venus and all of the other planets," he explains.
The sun is also constantly emitting charged particles into space. These electrons and protons manifest themselves in our night skies as the aurora borealis or northern lights. But solar storms caused by sunspots can throw huge amounts of particles out into space, affecting what is known as "space weather".
"Technological consequences of this space weather include interruption of GPS signals and radio blackouts. Just a couple of weeks ago there were major radio blackouts due to a massive solar storm," says Gallagher.
A large part of IHY is devoted to education and a public outreach effort to "demonstrate the beauty and relevance of the sun to the general public". Gallagher and his colleagues at Trinity, in collaboration with Queen's University and Armagh Planetarium, will be visiting secondary schools on both sides of the Border to speak to students about the Sun's impact on life on Earth, and also the future of interplanetary exploration.
Voyagers I and II, space probes launched almost 30 years ago to carry out fly-bys of Jupiter and Saturn have only recently reached the boundary of the heliosphere and the now vintage spacecraft are still transmitting valuable data all the way back home to Earth, says Gallagher.
"There is still debate about whether they really are at the edge of the heliosphere but humankind will probably never travel this far away again in our lifetime," he adds.
Find out more about International Heliophysical Year at www.ihy2007.ie