The Sun, Our Star: Space weather

At any moment, the predictions of your local weather forecaster might be suddenly superseded by space weather, a special breed of storms fomented on the Sun and launched toward Earth with potentially devastating consequences.

Most of the time, the solar wind billowing out from the Sun blows right past our planet without causing any ill effects whatsoever, but today, with our navigation and communications technology dependent on satellite based systems, a downdraft of space weather could disrupt entire countries.

Dava Sobel turns to Aditya L1, a new satellite under construction in India, to learn how many countries are developing their own eyes to watch the sun from space.

To know the Sun is an age-old dream of humankind. For centuries, astronomers contented themselves with analysing small sips of sunlight collected through specialised instruments. They chased after eclipses that exposed otherwise hidden layers of the Sun’s substance, and they launched Earth and Sun-orbiting observatories to monitor our star from space. Today, several satellites ‘watch’ our star from outer space. In August 2018, NASA’s Parker Solar Probe, set off on a mission to go so far as to ‘touch the sun’ for the first time.

Our view of the sun from here is relatively murky, but it’s a trade-off we Earthlings have to accept: the protective bubble of the Earth’s magnetic sphere and atmosphere provides air to breathe and a shield against harmful radiation, but it distorts our view of the heavens. Nevertheless, astronomers have managed to piece together an understanding of the stars, and especially the Sun itself: how it’s constructed, how it behaves, how it came to be, forming from a vast cloud of cold hydrogen gas and the dust of older stars in a sparsely populated region of the Milky Way.

In five programmes, author Dava Sobel orbits the sun, getting as close as she dares, to understand the immense relationship we have with our nearest star.

Music composed by Chris O'Shaughnessy.
Producer: Jeremy Mortimer and Dakshiani Palicha

Audio for this programme was updated on 21 September 2020.

(Photo: An M9-class solar flare erupting on the Sun's northeastern hemisphere. Credit: Nasa/Solar Dynamics Observatory via AFP/Getty Images)