Category Archives: Philae

20 Facts About Rosetta and the Philae Lander

picture credit, ESA
picture credit, ESA


1. Gets its name from the famous Rosetta stone that led to the deciphering of Egyptian hieroglyphics almost 200 years ago

2. Will help scientists unlock the mysteries of the oldest building blocks of our Solar System – the comets

3. Changed target: its original target was comet 46P/Wirtanen, but after postponement of the initial launch a new one was found: Comet 67P/Churyumov-Gerasimenko

4. Was launched on 2 March 2004 and travelled 10 years to reach its rendezvous point Comet 67P/Churyumov-Gerasimenko

5. Has a mass of around three tonnes and carries 11 scientific instruments

6. Is the first solar-powered probe to fly beyond the orbit of Jupiter thanks to its two giant solar panels equipped with advanced solar-cell technology that allows it to operate over 800 million kilometres from the Sun, where sunlight levels are only 4% of those on Earth

7. Will fly an artificial tri-angle orbit around the comet and follow it closely as it approaches the Sun

8. Passed by the asteroid belt and imaged two asteroids on its journey to intercept the comet: 2867 Steins on 5 September 2008 and 21 Lutetia on 10 July 2010

9. Was put into a hibernation mode for two and a half years to travel in energy-saving mode, using the equivalent power of six light bulbs. The three-axis stabilisation attitude controlled spacecraft changed into a spin stabilised mode pointing to the Sun. During this period, Rosetta had to fend for itself and survive without any assistance from ground

10. Has to withstand temperature variations of -270°C to +100°C, surviving close to the Sun, at the distance of Venus, and in deep space

11. Will use optical navigation techniques when nearing its target, so it will autonomously keep the comet always in focus of the instruments

12. Will be the first spacecraft to examine from close proximity how a frozen comet is activated and transformed by the warmth of the Sun

13. Will obtain the first detailed images from a comet’s surface in close orbit

14. Will analyse and map the comet and determine the best place for its Philae lander to touch down

15. Will be the first spacecraft to deliver a lander to the Surface of a comet



16. Is named for the island in the river Nile on which an obelisk was found that had a bilingual inscription that helped to translate the hieroglyphs of the Rosetta stone

17. Weighs 100 kg and carries ten scientific instruments, including a drill to sample subsurface material

18. Will be released from a height of about one kilometre. Touchdown will take place at walking speed – less than one metre per second

19. Will be anchored by a harpoon to the surface once it touches down; the self-adjusting landing gear will ensure that it stays upright, even on a slope and its feet will drill into the ground to secure it to the comet’s surface in the low gravity environment

20. Will obtain the first images from a comet’s surface and make the first in situ analysis to learn what a comet is made from 10679tl

Text and featured image courtesy of Airbus Space and Defence