Number 20 : 24/05/2003
A scientific publication by SGF and NEODyS

Latest news: The case of 2003 EE16 was solved thanks to observations conducted on May 22/23 with one of the ESO VLT 8-m class telescopes at Cerro Paranal. 2003 EE16 was about magnitude 24 at the time of the observations. This data was obtained in the course of a Target of Opportunity program which was started in April and will continue to the end of September, at least. This initiative is dedicated to the observations of objects carrying remote collision solutions that cannot be observed with smaller facilities. Further information is available at :

NEOs' spacemissions: mission GIOTTO

In this issue we sill start a new series about past, present and future space missions involved in NEOs' science. In the series you will find, month by month, articles written by team members of the mission, 3d interactive models of the spacecrafts, images, links, and much, much more. The first special of the series is dedicated to the very famous Giotto mission.

Giotto mission's fast facts: an introduction

The Giotto mission, launched in 1985, was the first ESA deep space mission, designed to study Comet P/Halley, and also to studiy a second comet called P/Grigg-Skjellerup during its extended phase. Giotto was also the first spacecraft to image the nucleus of a comet, to encounter two comets and to change orbit by returning to Earth for a gravity assist... (read the introduction)


The Giotto mission to Comet Halley by Horst U. Keller - MPI

Interest in cometary physics was strongly stimulated when it has been realized that comets are building blocks of the planets and hence remnants of the early solar system.With the advent of space exploration it was only consequential that there was strong interest in a mission to a comet. At the end of the 1970s serious planning of a mission was triggered by the recurrence of the famous Comet Halley, one of the brightest short periodic comets. Its last very bright display in 1910 was still widely remembered. Comet Halley would reach its closest distance from the sun (perihelion) in 1986... click for the full article

The night of the comet by Ettore Perozzi - Telespazio

March 13, 1986: at ESOC, where Giotto's control centre is located, everything is ready for Europe's first deep space adventure. Here is the live coverage of the "Night of the comet"... click for the full article

The International Halley Watch by Donald K. Yeomans - JPL

For the 1986 return to perihelion of comet Halley, the International Halley Watch movement began in 1979 when JPL scientist Louis Friedman convinced NASA that a major international effort would be required to maximize the scientific return from ground-based and space-based observations of the comet during its upcoming apparition. Starting from that moment, The International Halley Watch idea grew into an international success story... click for the full article

Other resources:

a 3D interactive model of the spacecraft and of its scientific instruments. Navigate it, zoom it , and have fun ... (click here)
...and other resources such as images, links, video, a paper model of the spacecraft and much more (click here)

The history of NEOs' science

The discovery of EROS: a peculiar 3 body problem
by Ettore Perozzi - Telespazio

The discovery of the first NEA (433) Eros on the night of the 13 August 1898 was announced by Gustav Witt both, but this simple statement does not tell the whole story... click for the full article

Other articles:

Resonant returns, keyholes and all that
by Giovanni B. Valsecchi - Director of the SCN

A rather popular word in NEO jargon is "keyhole", introduced by Paul Chodas. Learn what this term means... click for the full article


Editor: Nanni Riccobono
Assistant Editor, web master and graphics: Livia Giacomini (

Spaceguard Foundation (SGF) is a private, non profit scientific organization aimed at supporting and co-ordinating NEO researches in the world.
NEO Dynamic Site (NEODyS) is a service offered by the University of Pisa (Italy). It provides catalogues, computation of orbits, and projection of the behavior of NEOs in the future, in order to identify possible impacts in advance.
Our sponsors:
The Astronomic Observatory of Mallorca (OAM)

Images of the heading: courtesy of NASA