If a large asteroid such as the recently identified 2004 VD17 – about 500 meters (1,640 feet) in diameter collides with the Earth it could spell disaster for much of our planet. As part of the European Space Agency’s (ESA) Near-Earth Object (NEO) deflecting mission Don Quijote, three teams of European industries are now carrying out studies on how to prevent this type of event.
ESA has been addressing the problem of how to prevent large NEOs from colliding with the Earth for some time. In 1996 the Council of Europe called for the agency to take action as part of a "long-term global strategy for remedies against possible impacts". Recommendations from other international organizations, including the United Nations and the Organization for Economic Cooperation and Development, soon followed.
In response to these and other calls, ESA commissioned a number of threat evaluation and mission studies through its General Studies Program. In July 2004 the preliminary phase was completed when a panel of experts appointed by ESA recommended giving the Don Quijote asteroid-deflecting mission concept maximum priority for implementation.
Now it is time for industry to put forward their best design solutions for the mission. Following an invitation to tender and the subsequent evaluation process, three industrial teams have been awarded a contract to carry out the mission phase-A studies. :
a team with Alcatel Alenia Space as prime contractor includes subcontractors and consultants from across Europe and Canada.
a consortium led by EADS Astrium, which includes Deimos Space from Spain and consultants from several European countries, brings their experience of working on the design of many successful ESA interplanetary missions such as Rosetta, Mars and Venus Express.
a team led by QinetiQ (U.K.), which includes companies and partners in Sweden and Belgium, draws on their expertise in mini and micro satellites including ESA’s SMART-1 and Proba projects.
This month the three teams began work and a critical milestone will take place in October when the studies will be reviewed by ESA with the support of an international panel of experts. The results of this phase will be available next year.
The risk of an asteroid hitting Earth is still small however, and may decrease even further when new observations are carried out, ESA said in a press release last week. "Still, if this or any other similar-sized object, such as 99942 Apophis, an asteroid that will come close enough to the Earth in 2029 to be visible to the naked eye, collided with our planet the energy released could be equivalent to a significant fraction of the world’s nuclear arsenal, resulting in devastation across national borders."
In 1908 an asteroid that exploded over Siberia devastated an unpopulated forest area. Had it arrived just a few hours later, Saint Petersburg or London could have been hit instead.
On the Earth alone the remains of more than 160 asteroid impacts have been identified, some as notorious as the Chicxulub crater located in Mexico’s Yucatan peninsula, believed to be a trace of the asteroid that caused the extinction of the dinosaurs 65 million years ago.
Because asteroids and comets are remnants of the turbulent period in which the planets were formed, they are in fact similar to ‘time capsules’ and carry a pristine record of those early days. By studying these objects it is possible to learn more about the evolution of our Solar System as well as ‘hints’ about the origins of life on Earth.
Comet 67P/Churyumov-Gerasimenko is one of these primitive building blocks and will be visited by ESA’s Rosetta spacecraft in 2014, as a part of a very ambitious mission – the first ever to land on a comet. Rosetta will also visit two main belt asteroids (Steins and Lutetia) on its way to comet 67P/Churyumov-Gerasimenko.
With an early launch provisionally scheduled for 2011, Don Quijote will serve as a ‘technological scout’ not only to mitigate the chance of the Earth being hit by a large NEO but also for the ambitious journeys to explore our solar system.
Don Quijote will comprise of two spacecraft – one of them (Hidalgo) impacting an asteroid at a very high relative speed while a second one (Sancho) would arrive earlier at the same asteroid and remain in its vicinity before and after the impact to measure the variation on the asteroid’s orbital parameters, as well as to study the object. Secondary mission goals have also been defined, which would involve the deployment of an autonomous surface package and several other experiments and measurements.