Search NASASearch

Engineering topics

Moldwin, Mark

Publications and source records attributed to Moldwin, Mark.

Development of New Research-Quality Low-Resource Magnetometers for Small Satellites

Researchers from the University of Michigan (UM) and NASA Goddard Spaceflight Center (GSFC) are partnering to develop new types of magnetometers for use on future small satellites. These new instruments not only fulfill stringent requirements for low-amplitude and high-precision measurements, they are also enabling the team to develop a new approach to achieve high-quality magnetic measurements from space, without the need for a boom. Typically, space-based magnetometers are deployed on a boom that extends from the space vehicle to reduce exposure of magnetic noise emanating from the spacecraft, which could potentially contaminate measurements. The UMNASA team has developed algorithms to identify and eliminate spacecraft magnetic noise, which will allow placement of these economical, science-grade instrument magnetometers on and inside the satellite bus, instead of on a boom.

Small Spacecraft

Lightning Studies Using VHF Waveform Data

Several atmospheric electricity studies were begun utilizing VHF lightning data obtained with the lightning detection and ranging system (LDAR) at the Kennedy Space Center (KSC). The LDAR system uses differences in the time of arrival of electromagnetic noise generated by the lightning process to seven antennas to calculate very accurate three dimensional locations of lightning. New software was developed to obtain the source location of multiple, simultaneous, and spatially separate lightning signatures. Three studies utilizing these data were begun this summer: (1) VHF observations of simultaneous lightning, (2) ground based VHF observations of transionospheric pulse pairs (TIPPs), and (3) properties of intra-cloud recoil streamers. The principal result of each of these studies are: (1) lightning commonly occurs in well separated (2-50 km) regions simultaneously, (2) large amplitude pairs of VHF pulses are commonly observed on the ground but had not been previously identified due to the large number of signals usually observed in the VHF noise of close lightning, and (3) the VHF Q-noise and pulse signatures associated with K-changes within intra-cloud lightning propagate at velocities of more than 10(exp 8) m/s. The interim results of these three studies are reviewed in this brief report.

Moldwin, Mark