| ||Darwin factsheet|
Finding Earth-like planets
Name The Darwin mission is named after British naturalist Charles Darwin who wrote the ground-breaking book The Origin of Species. Like its namesake, the Darwin mission is looking for the origins of life.
Description Darwin is a flotilla of four or five spacecraft that will search for Earth-like planets and analyse their atmospheres for the chemical signature of life. One spacecraft will be a central communications hub. The other three will function as 'light collectors', redirecting light beams to the hub spacecraft.
In addition the flotilla will be able to carry out high-resolution imaging using aperture synthesis, to provide pictures of celestial objects with unprecedented detail.
Launch Date to be defined in the context of ESA's Cosmic Vision scientific programme (two Soyuz-Fregat launches probably from Kourou).
Status In development.
Journey Instead of an orbit around the Earth, Darwin will be placed far away, beyond the Moon. At a distance of 1.5 million kilometres from Earth, in the opposite direction from the Sun, Darwin will operate from a special location known as Lagrangian Point L2.
Notes Looking for extrasolar planets, that is, planets orbiting around stars, is very hard. Even for nearby stars, it is like trying to see the difference between the feeble light from a candle next to a lighthouse from a point 1000 kilometres away.
At optical wavelengths, a star outshines an Earth-like planet by a thousand million to one. Partly to overcome this difficulty, Darwin will observe in the mid-infrared. At these wavelengths, the star-planet contrast drops to a million to one, making detection a little easier.
Another key reason for observing in the infrared is because life on Earth leaves its mark at these wavelengths. Gases emitted by planets and animals, and other markers, such as water, leave their fingerprints by absorbing certain wavelengths of infrared light. Darwin will look for these fingerprints.
To meet a general astrophysics objective, and to go one step beyond JWST, Darwin is designed to provide images with 10 - 100 times more detail than can be achieved now.
Darwin will also provide detailed images of other objects, such as active galaxy nucleii.
Last update: 17 November 2006