Engineering topics

Smith, Edward

Publications and source records attributed to Smith, Edward.

3 records

NASA NTRS2005

Chromospheric observations in the helium 1083NM line : a new instrument

Photometric, spectroscopic and polarimetric observations in the Helium 1083 nm line provide important diagnostic information on the structure and dynamics of the chromosphere. We describe an imaging instrument designed to probe the chromosphere in the Helium 1083nm line, based on a Helium magneto-optical filter. The instrument has two narrow passbands ((almost equal to) 0.006 nm) in the wings of each line of the Helium 1083nm triplet, high throughput and stability, making it ideal for making high cadence observations in support of studies of chromospheric dynamics and wave propagation. We describe the characteristics of the instrument and present preliminary observations and discuss future plans.

solar atmosphere↗

NASA NTRS1994

Compact Electric- And Magnetic-Field Sensor

Compact sensor measures both electric and magnetic fields. Includes both short electric-field dipole and search-coil magnetometer. Three mounted orthogonally providing triaxial measurements of electromagnetic field at frequencies ranging from near 0 to about 10 kHz.

Winterhalter, Daniel↗

NASA NTRS1986

Dynamic pressure model derived from an observation by Sakigake for Comet Halley on 31 December, 1985

An outstanding disconnection event (DE)-like knot was observed on 31 Dec. 1985 in P/Halley's tail. Analysis of the Sakigake/IMF data reveals that comet Halley did not encounter the heliospheric neutral sheet on the day, demanding a new explanation of the DE-like event. During this event, the comet encountered a high-speed solar wind from a coronal hole tongue of the Sun. The event can be explained by a dynamic pressure model, according to which the DE-like plasmoid was caused by a sudden increase in the dynamic pressure of the solar wind. A simulation result is found to support this interpretation. The dynamic pressure model for a comet can be compared with the mechanism of a possible geotail disturbance during a spacecraft triggered auroral substorm.

Saito, Takao↗