Engineering topics

Maas, D.

Publications and source records attributed to Maas, D..

3 records

NASA NTRS1992

The Ulysses dust experiment

The Ulysses dust experiment is intended to provide direct observations of dust grains with masses between 10 exp -16 g and 10 exp -6 g in interplanetary space, to investigate their physical and dynamical properties as functions of heliocentric distance and ecliptic latitude. Of special interest is the question of what portion is provided by comets, asteroids, and interstellar particles. The investigation is performed with an instrument that measures the mass, speed, flight direction, and electric charge of individual dust particles. It is a multicoincidence detector with a mass sensitivity 10 exp 6 times higher than that of previous in situ experiments which measured dust in the outer solar system. The instrument weighs 3.8 kg, consumes 2.2 W, and has a normal data transmission rate of 8 bits/s in nominal spacecraft tracking mode. On 27 October 1990 the instrument was switched-on. The instrument was configured to flight conditions and science data collection started immediately. In the period to 13 January 1991, at least 44 dust impacts have been recorded. Flux values are given covering the heliocentric distance range from 1.04 to 1.7 AU.

Gruen, E.↗

NASA NTRS1992

The Ulysses dust experiment

The Ulysses dust experiment is intended to provide direct observations of dust grains with masses between 10(exp -16) g and 10(exp -6) g in interplanetary space, to investigate their physical and dynamical properties as functions of heliocentric distance and ecliptic latitude. Of special interest is the question of what portion is provided by comets, asteroids and interstellar particles. The investigation is performed with an instrument that measures the mass, speed, flight direction, and electric charge of individual dust particles. It is a multicoincidence detector with a mass sensitivity 10(exp 6) times higher than that of previous in-situ experiments which measured dust in the outer solar system. The instrument weighs 3.8 kg, consumes 2.2 W, and has a normal data transmission rate of 8 bits/s in nominal spacecraft tracking mode. On 27 Oct. 1990 the instrument was switched on. The instrument was configured to flight conditions, and science data collection started immediately. At least 44 dust impacts had been recorded by 13 Jan. 1991. Flux values are given covering the heliocentric distance range from 1.04 to 1.7 AU.

Gruen, E.↗

NASA NTRS1990

The Galileo dust detector

The Galileo Dust Detector is intended to provide direct observations of dust grains with masses between 10(sup -19) kg and 10(sup -9) kg in interplanetary space and in the Jovian system, to investigate their physical and dynamical properties as functions of the distances to the Sun, to Jupiter and to its satellites, to study its interaction with the Galilean satellites and the Jovian magnetosphere. Surface phenomena of the satellites (like albedo variations), which might be effects of meteoroid impacts will be compared with the dust environment. Electric charges of particulate matter in the magnetosphere and its consequences will be studied; e.g. the effects of the magnetic field on the trajectories of dust particles and fragmentation of particles due to electrostatic disruption. The investigation is performed with an instrument that measures the mass, speed, flight direction and electric charge of individual dust particles. It is a multi-coincidence detector with a mass sensitivity 10(sup 6) times higher than that of previous in-situ experiments which measured dust in the outer solar system. The instrument weighs 4.2 kg, consumes 2.4 W, and has a normal data transmission rate of 24 bits/s in nominal spacecraft tracking mode. On December 29, 1989 the instrument was switched-on. After the instrument had been configured to flight conditions cruise science data collection started immediately. In the period to May 18, 1990 at least 168 dust impacts have been recorded. For 81 of these dust grains, masses and impact speeds have been determined. First flux values are also given.

Gruen, E.↗