Historic images are the dramatic climax of a 25-year dream

The Cassini-Huygens mission was launched on 15 October 1997, from Cape Canaveral Florida, but the origins of the £2bn project go back a quarter of century. It is a joint collaboration between the Nasa and the European Space Agency.

The Cassini-Huygens mission was launched on 15 October 1997, from Cape Canaveral Florida, but the origins of the £2bn project go back a quarter of century. It is a joint collaboration between the Nasa and the European Space Agency.

During its seven-year journey to Saturn and its moon Titan, the spacecraft travelled some two billion miles in a series of elliptical moves. To help it on its way, the spacecraft made four "gravity assist swing-bys" ­ two around Venus and one each around Earth and Jupiter ­ when it used the planets' gravitational pull to give it successive, cumulative boosts on its way.

Cassini, the mother spacecraft for the Huygens probe, is about as tall as a two-storey house and is one of the largest and heaviest interplanetary spacecraft ever built ­ only two Soviet built spacecraft were heavier. It arrived at Saturn last July when it successfully went into orbit. Cassini is due to continue orbiting and taking measurements of the planet and its complicated ring system for a further four years.

On Christmas Day, Cassini released the Huygens probe, which is about the size of a domestic washing machine. Powerless and without direct control from Earth, Huygens took a further 22 days to reach Titan, the largest of Saturn's moons.

The probe is named after Christiaan Huygens, a 17th century Dutch astronomer who discovered Titan in 1655. It has an outer carapace protecting an interior packed with six delicate instruments for making measurements of the moon's atmosphere and surface.

On its arrival at the outer fringes of Titan's atmosphere, a series of alarm clocks woke up the Huygens probe from its seven-year slumber. Travelling at 11,200mph, it made its initial entry into the dense atmosphere of the moon ­ which is ten times as thick as that on Earth ­ at an altitude of 789 miles above the surface. Its protective heat shield and set of three parachutes slowed the spacecraft down during its descent to the surface of Titan.

Pilot parachutes and friction with the atmosphere slowed the probe enough for the larger main parachute to be deployed. The probe would have reached the surface travelling at a relatively sedate 12mph.

After the heat shield fell away, the main scientific instruments were exposed, allowing them to gather crucial data ranging from the composition of the surrounding gasses to the velocity of sound. As it descended the probe rotated to allow its cameras to scan panoramic views. Its cameras ­ which took images in digital slices that have to be reconfigured by computers ­ took more than 1,000 pictures.

Before yesterday's events, Professor Ian Halliday, chief executive of the Particle Physics and Astronomy Research Council, said the ambitious targets of the Huygens mission should not be underestimated. "Superlatives can come easy when talking about space missions but this particular voyage of scientific discovery is truly awesome," Professor Halliday said.

"Titan is a mysterious place and raises many scientific questions. Its thick atmosphere is mostly nitrogen, but there are also methane and many other organic compounds. Some of them would be signs of life if they were on our planet.

"Organic compounds form when sunlight destroys methane. If sunlight is continuously destroying methane on Titan, how is methane getting into the atmosphere," he said.

Scientists believe the composition of Titan's atmosphere resembles that of Earth's four billion years ago, when life had yet to evolve here. Monica Grady, a planetary scientist at the Natural History Museum in London, said: "Because of the similarities in the atmospheres, it will give us a fascinating analogue of the type of reactions that would have been happening on Earth."

Scientists calculated that the Huygens probe had a 70 per cent chance of surviving the soft landing. Yesterday's signals show that it has survived the most dramatic fall in the history of interplanetary exploration.

PUSHING THE FINAL FRONTIER

4 October, 1957: Sputnik 1, the first man-made object to orbit the Earth, is launched by the USSR.

12 April, 1961: Yuri Gargarin becomes the first man in space aboard Vostok 1. He orbits the Earth once.

20 July, 1969: Neil Armstrong and "Buzz" Aldrin make the first landing on the Moon using Apollo 11.

15 December, 1970: Soviet Venera 7 is the first probe to land on Venus, transmitting for 23 minutes.

2 March, 1972: Pioneer 10 is launched. It returns the first close-up images of Jupiter in 1973.

5 April, 1973: Pioneer 11 is launched, flying past Saturn in September 1979, where it discovers new rings.

3 September, 1976: Viking 2 lands on Mars where it discovers water frost.

August-September, 1977: Voyager 1 and 2 leave Earth to meet with Jupiter in 1979 and Saturn in 1980.

12 April, 1981: The first manned mission of the original space shuttle, Columbia, is launched.

2 July, 1985: The European Space Agency launches the Giotto spacecraft. It encounters Halley's Comet in 1986.

January, 1986: Voyager 2 flies past Uranus.

24 April, 1990: The space shuttle Discovery deploys the Hubble space telescope.

7 December, 1995: The Galileo spacecraft drops a probe into Jupiter's atmosphere.

31 March, 1997: Contact with Pioneer 10 is terminated. The probe has travelled 6.7 billion miles from Earth.

14 February, 2001: The NEAR probe lands on the asteroid 433 Eros.

25 December, 2005: Scientists lose contact with British-built Beagle 2 after it lands on Mars.

18 May, 2004: Robotic exploration rover Opportunity finds signs of water on Mars.

Suggested Topics
Travel
travel
News
Tim Vine has won the funniest joke award at the Edinburgh Festival 2014
peopleTim Vine, winner of the Funniest Joke of the Fringe award, has nigh-on 200 in his act. So how are they conceived?
Sport
sportBesiktas 0 Arsenal 0: Champions League qualifying first-leg match ends in stalemate in Istanbul
News
Jamie and Emily Pharro discovering their friend's prank
video
PROMOTED VIDEO
News
ebooksAn evocation of the conflict through the eyes of those who lived through it
Sport
Manchester United are believed to have made a £15m bid for Marcos Rojo
sportWinger Nani returns to Lisbon for a season-long loan as part of deal
News
news
News
i100
Arts and Entertainment
O'Toole as Cornelius Gallus in ‘Katherine of Alexandria’
filmSadly though, the Lawrence of Arabia star is not around to lend his own critique
Life and Style
fashion
Independent
Travel Shop
the manor
Up to 70% off luxury travel
on city breaks Find out more
santorini
Up to 70% off luxury travel
on chic beach resorts Find out more
sardina foodie
Up to 70% off luxury travel
on country retreats Find out more
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Junior DBA (SQL Server, T-SQL, SSIS, SSAS) London - Finance

£30000 - £33000 per annum + Benefits + Bonus: Harrington Starr: Junior DBA (SQ...

Business Anaylst

£60000 - £75000 per annum + BONUS + BENEFITS: Harrington Starr: Business Anal...

Senior Project Manager

£60000 - £90000 per annum + Bonus: Harrington Starr: Global leading Energy Tra...

Associate CXL Consultant

£40000 - £60000 per annum + BONUS + BENEFITS: Harrington Starr: CXL, Triple Po...

Day In a Page

Ferguson: In the heartlands of America, a descent into madness

A descent into madness in America's heartlands

David Usborne arrived in Ferguson, Missouri to be greeted by a scene more redolent of Gaza and Afghanistan
BBC’s filming of raid at Sir Cliff’s home ‘may be result of corruption’

BBC faces corruption allegation over its Sir Cliff police raid coverage

Reporter’s relationship with police under scrutiny as DG is summoned by MPs to explain extensive live broadcast of swoop on singer’s home
Lauded therapist Harley Mille still in limbo as battle to stay in Britain drags on

Lauded therapist still in limbo as battle to stay in Britain drags on

Australian Harley Miller is as frustrated by court delays as she is with the idiosyncrasies of immigration law
Lewis Fry Richardson's weather forecasts changed the world. But could his predictions of war do the same?

Lewis Fry Richardson's weather forecasts changed the world...

But could his predictions of war do the same?
Kate Bush asks fans not to take photos at her London gigs: 'I want to have contact with the audience, not iPhones'

'I want to have contact with the audience, not iPhones'

Kate Bush asks fans not to take photos at her London gigs
Under-35s have rated gardening in their top five favourite leisure activities, but why?

Young at hort

Under-35s have rated gardening in their top five favourite leisure activities. But why are so many people are swapping sweaty clubs for leafy shrubs?
Tim Vine, winner of the Funniest Joke of the Fringe award: 'making a quip as funny as possible is an art'

Beyond a joke

Tim Vine, winner of the Funniest Joke of the Fringe award, has nigh-on 200 in his act. So how are they conceived?
The late Peter O'Toole shines in 'Katherine of Alexandria' despite illness

The late Peter O'Toole shines in 'Katherine of Alexandria' despite illness

Sadly though, the Lawrence of Arabia star is not around to lend his own critique
Wicken Fen in Cambridgeshire: The joy of camping in a wetland nature reserve and sleeping under the stars

A wild night out

Wicken Fen in Cambridgeshire offers a rare chance to camp in a wetland nature reserve
Comic Sans for Cancer exhibition: It’s the font that’s openly ridiculed for its jaunty style, but figures of fun have their fans

Comic Sans for Cancer exhibition

It’s the font that’s openly ridiculed for its jaunty style, but figures of fun have their fans
Besiktas vs Arsenal: Five things we learnt from the Champions League first-leg tie

Besiktas vs Arsenal

Five things we learnt from the Champions League first-leg tie
Rory McIlroy a smash hit on the US talk show circuit

Rory McIlroy a smash hit on the US talk show circuit

As the Northern Irishman prepares for the Barclays, he finds time to appear on TV in the States, where he’s now such a global superstar that he needs no introduction
Boy racer Max Verstappen stays relaxed over step up to Formula One

Boy racer Max Verstappen stays relaxed over step up to F1

The 16-year-old will become the sport’s youngest-ever driver when he makes his debut for Toro Rosso next season
Fear brings the enemies of Isis together at last

Fear brings the enemies of Isis together at last

But belated attempts to unite will be to no avail if the Sunni caliphate remains strong in Syria, says Patrick Cockburn
Charlie Gilmour: 'I wondered if I would end up killing myself in jail'

Charlie Gilmour: 'I wondered if I'd end up killing myself in jail'

Following last week's report on prison suicides, the former inmate asks how much progress we have made in the 50 years since the abolition of capital punishment