Hubble assists Rosetta comet mission

September 9, 2003

Paris, 08 Sep 2003

Results from the NASA/ESA Hubble Space Telescope have played a major role in preparing ESA's ambitious Rosetta mission for its new target, comet 67P/Churyumov-Gerasimenko.

Hubble has been used to make precise measurements of the size, shape and rotational period of the comet. Information that is essential if Rosetta is to rendezvous with the comet and then drop down a probe, something never before attempted and yet a major step towards elucidating the origins of the solar system.

Observations made by Hubble in March this year revealed that comet 67P/Churyumov-Gerasimenko (67P/C-G) is approximately five by three kilometres in size and shaped like a rugby ball. ESA mission scientists were concerned about the exact size of the solid nucleus, which is needed to adapt the mission to the comet's gravity.

"Although 67P/C-G is roughly three times larger than the original Rosetta target, its highly elongated shape should make landing on its nucleus feasible, now that measures are in place to adapt the lander package to the new scenario," says Dr Philippe Lamy of the Laboratoire d'Astronomie Spatiale in France, who is presenting the Hubble results on comet 67P/C-G today at the annual meeting of the Division for Planetary Sciences of the American Astronomical Society in California, USA.

Mission scientists began looking for an alternative target when the Rosetta mission's launch date was postponed. The delay meant that the original target comet, 46P/Wirtanen, was no longer easily reachable. But scientists did not have enough information on the back-up comet, 67P/C-G, and sought data from the largest telescopes.

Using a technique developed over the past decade by Philippe Lamy, Imre Toth (Konkoly Observatory, Hungary), and Harold Weaver (Johns Hopkins University Applied Physics Laboratory, Laurel, USA), the team snapped 61 Hubble images of comet 67P/C-G over a period of 21 hours on 11 and 12 March. Hubble's Wide Field Planetary Camera 2 isolated the comet's nucleus from the coma, the diffuse gas surrounding the nucleus, quickly providing the figures required. The telescope showed that the nucleus is ellipsoidal and measured its rotation rate at approximately 12 hours.

Rosetta's launch is currently planned for February 2004, with a rendezvous with the comet about 10 years later.

Notes for editors

The team is made up of P. L. Lamy and L. Jorda (Laboratoire d'Astronomie Spatiale, France), I. Toth (Konkoly Observatory, Hungary), and H.A. Weaver (Johns Hopkins University Applied Physics Laboratory). The movie simulation of the Hubble results is provided by Mikko Kaasalainen (University of Helsinki, Finland) and Pedro Gutierrez (Laboratoire d'Astronomie Spatiale, France).

The observations were made possible through a special programme approved by the Director of the Space Telescope Science Institute, S. Beckwith.

For more information, please contact:

Philippe Lamy
Laboratoire d'Astronomie Spatiale, France
Cellular: +33-630-14-92-33
E-mail: lamy@astrsp-mrs.fr

Lars Lindberg Christensen
Hubble European Space Agency Information Centre, Garching, Germany
Tel: +49-89-3200-6306 (089 within Germany)
Cellular (24 hr): +49-173-3872-621 (0173 within Germany)
E-mail: lars@eso.org

Ray Villard
Space Telescope Science Institute, Baltimore, MD, USA
Tel: +1-410-338-4514)
E-mail: villard@stsci.edu

Michael Buckley
Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
Tel: +1-443-778-7536
E-mail: michael.buckley@jhuapl.edu

European Space Agency
http://www.esa.int/export/esaCP/index.ht ml
Item source: http://www.esa.int/export/esaCP/SEMB8SZO 4HD_index_0.html

You've reached your article limit.

Register to continue

Registration is free and only takes a moment. Once registered you can read a total of 3 articles each month, plus:

  • Sign up for the editor's highlights
  • Receive World University Rankings news first
  • Get job alerts, shortlist jobs and save job searches
  • Participate in reader discussions and post comments
Register

Have your say

Log in or register to post comments

Most Commented

James Fryer illustration (27 July 2017)

It is not Luddism to be cautious about destroying an academic publishing industry that has served us well, says Marilyn Deegan

Hand squeezing stress ball
Working 55 hours per week, the loss of research periods, slashed pensions, increased bureaucracy, tiny budgets and declining standards have finally forced Michael Edwards out
Jeffrey Beall, associate professor and librarian at the University of Colorado Denver

Creator of controversial predatory journals blacklist says some peers are failing to warn of dangers of disreputable publishers

Kayaker and jet skiiers

Nazima Kadir’s social circle reveals a range of alternative careers for would-be scholars, and often with better rewards than academia

hole in ground

‘Drastic action’ required to fix multibillion-pound shortfall in Universities Superannuation Scheme, expert warns