The ice particles in Saturn’s E ring and measurements of the Cassini Cosmic Dust Analyzer and its High Rate Detector
Tervo, Wille (2019-04-29)
Tervo, Wille
W. Tervo
29.04.2019
© 2019 Wille Tervo. Tämä Kohde on tekijänoikeuden ja/tai lähioikeuksien suojaama. Voit käyttää Kohdetta käyttöösi sovellettavan tekijänoikeutta ja lähioikeuksia koskevan lainsäädännön sallimilla tavoilla. Muunlaista käyttöä varten tarvitset oikeudenhaltijoiden luvan.
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:oulu-201904301556
https://urn.fi/URN:NBN:fi:oulu-201904301556
Tiivistelmä
This thesis is a literature review on Saturn’s E ring and the respective results obtained by the Cassini Cosmic Dust Analyzer and its subsystem High Rate Detector during Cassini-Huygens mission to Saturn.
The Cassini spacecraft spent 13 years orbiting Saturn while studying the planet, its many satellites and its various rings. One of the most interesting rings to an in-situ instrument is the vast E ring, which originates from the tiny ice-surfaced moon Enceladus. Enceladus’ active southern polar region has massive geysir-like phenomena powered by the moon’s global subsurface ocean. The jets of (dominantly) water vapor and ice grains are launched to such heights that some of the ice particles do not fall back on the moon and form the E ring. The ring is constantly supplied with new material and it has spread to cover an orbital distance of 1 000 000 kilometers, making it the second largest planetary ring in the Solar System.
The E ring was previously observed with different imaging techniques, but the Cassini opened new research possibilities for in-situ observations with its various instruments. For this thesis, a major focus is the Cosmic Dust Analyzer (CDA) instrument and its subsystem, the High Rate Detector (HRD). The CDA is an instrument for determining properties, such as mass, velocity and mass spectra, of dust particles that collide with it, while the HRD is used to get data on the number of occurring impacts, ie. number density of particles. These properties allowed scientists to determine, for example, the composition of particles within the E ring and the ring’s spatial density. The CDA and the HRD had a crucial impact all the way to the last years of the mission where it played a key role in exploring the subsurface conditions of Enceladus and its habitability.
The Cassini spacecraft spent 13 years orbiting Saturn while studying the planet, its many satellites and its various rings. One of the most interesting rings to an in-situ instrument is the vast E ring, which originates from the tiny ice-surfaced moon Enceladus. Enceladus’ active southern polar region has massive geysir-like phenomena powered by the moon’s global subsurface ocean. The jets of (dominantly) water vapor and ice grains are launched to such heights that some of the ice particles do not fall back on the moon and form the E ring. The ring is constantly supplied with new material and it has spread to cover an orbital distance of 1 000 000 kilometers, making it the second largest planetary ring in the Solar System.
The E ring was previously observed with different imaging techniques, but the Cassini opened new research possibilities for in-situ observations with its various instruments. For this thesis, a major focus is the Cosmic Dust Analyzer (CDA) instrument and its subsystem, the High Rate Detector (HRD). The CDA is an instrument for determining properties, such as mass, velocity and mass spectra, of dust particles that collide with it, while the HRD is used to get data on the number of occurring impacts, ie. number density of particles. These properties allowed scientists to determine, for example, the composition of particles within the E ring and the ring’s spatial density. The CDA and the HRD had a crucial impact all the way to the last years of the mission where it played a key role in exploring the subsurface conditions of Enceladus and its habitability.
Kokoelmat
- Avoin saatavuus [32026]