LINDA – the Astrid-2 Langmuir probe instrument

Abstract

Abstract. The Swedish micro-satellite Astrid-2, designed for studies in magnetosperic physics, was launched into orbit on 10 December 1998 from the Russian cosmodrome Plesetsk. It was injected into a circular orbit at 1000 km and at 83 degrees inclination. The satellite carried, among other instruments, a double Langmuir Probe instrument called LINDA (Langmuir INterferometer and Density instrument for Astrid-2). The scientific goals of this instrument, as well as the technical design and possible modes of operation, are described. LINDA consists of two lightweight deployable boom systems, each carrying a small spherical probe. With these probes, separated by 2.9 meters, and in combination with a high sampling rate, it was possible to discriminate temporal structures (waves) from spatial structures. An onboard memory made it possible to collect data also at times when there was no ground contact. Plasma density and electron temperature data from all magnetic latitudes and for all seasons have been collected.

Astrid-2, an advanced microsatellite for auroral research

“…Despite the lack of ASC data on Astrid-2, we could, however, retrieve the attitude (to an accuracy of half a degree) from the high-quality magnetic field measurements. Descriptions of the various instruments and their capabilities are presented in the accompanying studies of this special issue (see Holback et al, 2001;Norberg et al, 2001). …”

DC Langmuir Probe for Measurement of Space Plasma: A Brief Review

“…Although these satellites are not purely dedicated to ionosphere study, all of these satellites carry a DC Langmuir probe (Holback et al 2001;Lebreton et al 2006;Buchert et al 2014). The data measured by Astrid has shown unexpectedly high T e (Holback et al 2001), and the T e measured by CHAMP at night is sometimes overestimated.…”

“…Although these satellites are not purely dedicated to ionosphere study, all of these satellites carry a DC Langmuir probe (Holback et al 2001;Lebreton et al 2006;Buchert et al 2014). The data measured by Astrid has shown unexpectedly high T e (Holback et al 2001), and the T e measured by CHAMP at night is sometimes overestimated. The T e values at night (period 20 to 03 LT) during the March equinox are sometimes about 500K higher than the HINOTORI satellite data indicates (Su et al 1995Balan et al 1997).…”

“…Since a DC Langmuir probe was first flown in a V-2 rocket from White Sands in New Mexico, USA (Reifman & Dow 1949) to measure the lower E-region ionosphere, the probe has been flown in many sounding rockets and satellites there (Boggess et al 1959;Spencer et al 1965;Brace et al 1973;Brace 1998) and in Russia (Andreyeva et al 1971). Even now, DC Langmuir probes are generally employed in low earth orbit satellites, such as Astrid (Holback et al 2001), Detection of ElectroMagnetic Emissions Transmitted from Earthquake Regions (DEMETER) (Lebreton et al 2006), Challenging Minisatellite Payload (CHAMP) (Cooke et al 2003), SWARM (Buchert et al 2015), and Communications/Navigation Outage Forecasting System (C/NOFS) (Costa et al 2014). This is because N e and T e are two basic parameters that are fundamental for study of the ionosphere/plasmasphere.…”

EMMA - the Electric and Magnetic Monitor of the Aurora on Astrid-2

“…To facilitate the inclusion of adequate instrumentation on a space and mass constrained micro-satellite, significant new instrument development was necessary. Holback et al (2001) describe the Langmuir probe instrument and Norberg et al (2001) describe the particle detectors and UV imagers. Overviews of the Astrid-2 mission are given by Blomberg et al (1999) and Marklund et al (1997b;2001a).…”