altimeter measurements
41Wave radar — Ocean surface waves can be measured by several radar remote sensing techniques. Several instruments based on a variety of different concepts and techniques are available to the user and these are all often called wave radars. This article (see… …
42geoid — geoidal, adj. /jee oyd/, n. 1. an imaginary surface that coincides with mean sea level in the ocean and its extension through the continents. 2. the geometric figure formed by this surface, an ellipsoid flattened at the poles. [1880 85; < Gk… …
43Pitot-static system — A pitot static system is a system of pressure sensitive instruments that is most often used in aviation to determine an aircraft s airspeed, Mach number, altitude, and altitude trend. A pitot static system generally consists of a pitot tube, a… …
44Measuring instrument — Captain Nemo and Professor Aronnax contemplating measuring instruments in Twenty Thousand Leagues Under the Sea …
45LIDAR — A FASOR used at the Starfire Optical Range for LIDAR and laser guide star experiments is tuned to the sodium D2a line and used to excite sodium atoms in the upper atmosphere …
46List of astronomy acronyms — This is a compilation of acronyms commonly used in astronomy. Most of the acronyms are drawn from professional astronomy and are used quite frequently in scientific publications. However, a few of these acronyms are frequently used by the general …
47Mars Express — CG image of Mars Express Operator ESA Mission type Orbiter + Lander Satellite of …
48Synthetic aperture radar — (SAR) is a form of radar in which the highly directional (and thus very large) rotating antenna used by conventional radar is replaced with many low directivity small stationary antenna positions scattered over some area near or around the target …
49Above ground level — In aviation and atmospheric sciences, an altitude is said to be above ground level (AGL) when it is measured with respect to the underlying ground surface. This is as opposed to above mean sea level (AMSL), or in broadcast engineering, height… …
50Mars — /mahrz/, n. 1. the ancient Roman god of war and agriculture, identified with the Greek god Ares. 2. Astron. the planet fourth in order from the sun, having a diameter of 4222 miles (6794 km), a mean distance from the sun of 141.6 million miles… …
