Microwave Components for Deep Space Missions to Comets

Comets are the remainders of material formed in the coldest part of our solar system. Comet impacts played a major role in the evolution of the Earth, primarily during its early history billions of years ago. Some believe that they brought water and a variety of organic molecules to Earth. Thales has contributed to cometary missions and aided the discovery of what these organic ‘time capsules’ can reveal.
 

Rosetta and Philae

Rosetta is a space probe built and launched by the European Space Agency. Along with Philae, its lander module, Rosetta is performing a detailed study of comet 67P/Churyumov–Gerasimenko (67P). Rosetta was launched on 2 March 2004 and reached the comet on 6 August 2014, becoming the first spacecraft to orbit a comet. On 12 November 2014, the mission performed the first successful landing on a comet. As the space probe  approaches the  end of its natural lifespan, Rosetta is set to complete its mission in a controlled descent to the comet's surface on 30 September 2016.  Rosetta will be collecting invaluable scientific data until the very end. During the  dramatic final hours of descent there will be a unique opportunity to capture very high-resolution images  and make important measurements.

Thales’ traveling wave tubes (TH4604C) in the 30 watt power range are installed in the X band transponder and play a vital role for communications with Earth, such as receiving images of the comet and analysing the transmitted data.

Giotto

The mission was launched in July 1985 with the objective of studying the Comet 1P/Halley. The major objectives were to obtain colour photographs of the comet’s nucleus, determine the composition of volatile components in the cometary coma, characterise the physical and chemical processes that occur in the cometary atmosphere, determine the composition of dust particles, measure the total gas-production rate, dust flux and dust-to-gas ratio; and examine plasma flows resulting from the cometary-solar wind interaction.
Giotto successfully approached the comet at a distance of 596 kilometres. Giotto provided clear images of the nucleus, which was very dark, suggesting it was covered in dust. It discovered that roughly 3 tonnes of material was ejected per second, 80% of which was water, 10% was carbon monoxide and 2.5% was a mix of ammonia and sodium.

Thales provided X band TWTs (TH4604C) in the 20 watt power range to enable data transmission.

OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security – Regolith Explorer)

OSIRIS-REx is the third selected mission in the New Frontiers Program and will be launched in 2016. Its target is the asteroid named (101955) Bennu (1999 RQ36) which was discovered in 1999 and has a diameter of 575 metres.
The OSIRIS-REx mission will return the first samples ever from this special type of asteroid. The reason the asteroid is unique is that 1999 RQ36 is a time capsule from the early solar system rich with organic compounds that may have seeded life on Earth.
OSIRIS-REx will provide geologic samples that will return to Earth in the year 2023 and will enable precise analyses unequalled by any spacecraft-based instruments. It will be the first time that pristine carbonaceous materials can be analysed in laboratories on Earth.

Thales has provided X band TWTs (TH4300C) in the 100 watt power range to enable the mission to transmit data back to Earth.