Headlines > News > Astrium missions to study Earth-bound asteroid Apophis win international prizes

Astrium missions to study Earth-bound asteroid Apophis win international prizes

Published by Klaus Schmidt on Mon Mar 3, 2008 5:02 pm
More share options

(EADS Astrium) – Prize winning second and third place for space scientists in Planetary Society Apophis competition
Competition co-sponsored by NASA and the European Space Agency (ESA)
Winning designs to be presented to world space agencies

Friedrichshafen/Stevenage – Astrium space scientists and engineers in Friedrichshafen and Stevenage in two separate proposals have come in second and third in a worldwide Planetary Society competition put on in collaboration with NASA and ESA for a mission to tag an asteroid heading for Earth in 2029. The competition received 37 mission proposals from 20 countries on 6 continents. The winning entry was led by SpaceWorks Engineering of Atlanta, Georgia, USA, and second place was given to a team of Deimos Space of Madrid, Spain and Astrium, Friedrichshafen, Germany. The proposal submitted by Astrium Stevenage,UK, was awarded third place.

Apophis is a 300 metre wide primordial remnant of our solar system – thought to be made largely of rock – circling the Sun in an orbit that brings it close to the Earth. In 2029 it will have a close encounter with Earth. Apophis is subject to gravitational and non-gravitational forces that could slightly shift its orbit to put it on a collision course with Earth in 2036.

Astrium Germany´s mission proposal “A-Track” submitted to the Planetary Society in cooperation with the Spanish company Deimos as prime bidder and further scientific support by the Universities of Stuttgart and Pisa was awarded the second place and a $10 000 prize. The selection of Deimos and Astrium Germany in a worldwide competition as the leading European team underlines the excellence and competence of the involved system engineers, which has been established in a long standing close cooperation with regard to asteroid mission preparation within the European Space Agency´s Don Quijote programme. Don Quijote is a mission concept under development since 2003, which aims -besides scientific investigation of the target body- at probing potential near earth asteroid deflection methods. It features both, an orbiter and impactor spacecraft launched sequentially to the same target. The orbiter investigates the target body prior and after the impactor creates a crater and exposes primitive material which can be investigated in detail by the remote sensing instrumentation on the orbiter. Also the momentum transfer and the complex interior structure shall be determined by precise radio tracking.

The “A-Track” proposal foresees a launch in April 2013 to the near earth asteroid Aphophis using chemical propulsion for transfer and orbit insertion after 11 month transfer time. Precise radio-tracking from earth in X and K band while orbiting the asteroid will allow to determine the orbit parameters and the complex influence of non-gravitational forces (solar light pressure, thermal radiation, Yarkovsky effect) affecting those with unprecedented precision. The mission goal of a tracking accuracy of 14 km (3 sig) will be surpassed after 2 weeks of measurement and will reach order of 200 m in less than one year. That level of precision will allow a forecast of the earth close encounter parameters and whether the asteroid will pass earth within the “keyhole position” putting it onto a collision course for the next close encounter in 2036. Albeit the probability of this to happen is not very high for the case of Aphophis, the mission is a full rehearsal to cope with similar threats to be expected in coming years and once an appreciable census of near earth objects is established in the coming years. Any potential deflection measures require this type of precision knowledge prior to taking action in order to not unintentionally worsening the situation. Equally important is the exact knowledge of the asteroid composition (pile of gravel, solid), which will be investigated as well via remote sensing equipment on board of the orbiter.

A-Track is designed as a mission to make maximum use of existing and proven components derived e.g. from the existing missions MarsExpress, VenusExpress, Rosetta, LISAPathfinder and other technology developments at Astrium in order to meet the schedule and cost constraints.

The second Astrium mission proposal called “Apex” submitted to the Planetary Society was awarded third place and a $5,000 prize further confirming Astrium´s competence in that matter.

Similar to A-Track, the Apex mission concept foresees a launch in 2013 to rendezvous with the asteroid and plot its orbit accurately, map its surface in detail, and determine its thermal properties.

Under the proposal the Astrium Apex mission would rendezvous with Apophis in January 2014 and spend three years sending data back to scientists and engineers on Earth. The mission concept differs from A-Track in payload composition, budgets and cost. From the data, orbit modelling would enable an accurate prediction of the risk of collision.

Both Astrium teams in Friedrichshafen and Stevenage, respectively, have been and are involved in related activities for solar system research pursued by the European Space Agency like Rosetta, a comet orbiter and lander launched in 2004 and Bepi Colombo, a Mercury orbiter to be launched in 2013 , both missions developed in Friedrichshafen as prime contractor and further in the successful planetary orbiters MarsExpress and Venus Express.

Presently, both teams are preparing for the upcoming asteroid sample return mission Marco Polo, which has been recently selected as a candidate within ESA´s Cosmic Vision programme. Marco Polo is a mission presumably in cooperation with Japan´s JAXA for a sample return of primitive asteroid material.

It is imperative to collect data on Apophis as soon as possible to know whether it is on a collision course or not. The safest way to avoid disaster is to nudge the asteroid to change its orbit. Leaving it too long would make it impossible to build a spacecraft powerful enough to move its orbit. Ideally the orbit would need to be changed before 2025 to be sure it misses the Earth.

Apophis is known to be spinning and the effect of heat from the sun’s rays being released affects the orbit – the Yarkovsky Effect. Understanding this process in more detail is crucial to determining whether the asteroid will fly through the “keyhole” – at present it is not clear how the object is spinning.

The Planetary Society says: “If Earth were ever going to mount a defence against a dangerous asteroid, international cooperation would be vital in protecting the planet. That spirit of international cooperation was exemplified by the teams, which won second and third place overall.”

The Planetary Society is an international group founded by among others Carl Sagan (http://www.planetary.org). According to current modelling, Apophis will come within 36,000 km of Earth in 2029 – nearer than the geostationary satellites which provide global communications…many of which were built by the Astrium teams in Europe.

About Astrium
Astrium, a wholly owned subsidiary of EADS, is dedicated to providing civil and defence space systems and services. In 2006, Astrium had a turnover of €3.2 billion and 12,000 employees in France, Germany, the United Kingdom, Spain and the Netherlands. Its three main areas of activity are Astrium Space Transportation for launchers and orbital infrastructure, and Astrium Satellites for spacecraft and ground segment, and its wholly owned subsidiary Astrium Services for the development and delivery of satellite services.

EADS is a global leader in aerospace, defence and related services. In 2006, EADS generated revenues of €39.4 billion and employed a workforce of more than 116, 000.

Feel free to discuss this article in the forum…

No comments
Start the ball rolling by posting a comment on this article!
Leave a reply
You must be logged in to post a comment.
© 2018 The International Space Fellowship, developed by Gabitasoft Interactive. All Rights Reserved.  Privacy Policy | Terms of Use