Flik
Encyclopedia
In radio astronomy
, the unit flik was coined by a group at Lockheed
in Palo Alto, California
as a substitute for the SI derived unit
W cm−2 sr−1 µm−1, or watt
s divided by centimeters squared, steradian
s, and micrometers
.
This is primarily used as a unit of spectral radiance or sterance. While it started out used only in Lockheed, many in the radio astronomy field adopted its use.
Radio astronomy
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The initial detection of radio waves from an astronomical object was made in the 1930s, when Karl Jansky observed radiation coming from the Milky Way. Subsequent observations have identified a number of...
, the unit flik was coined by a group at Lockheed
Lockheed Corporation
The Lockheed Corporation was an American aerospace company. Lockheed was founded in 1912 and later merged with Martin Marietta to form Lockheed Martin in 1995.-Origins:...
in Palo Alto, California
Palo Alto, California
Palo Alto is a California charter city located in the northwest corner of Santa Clara County, in the San Francisco Bay Area of California, United States. The city shares its borders with East Palo Alto, Mountain View, Los Altos, Los Altos Hills, Stanford, Portola Valley, and Menlo Park. It is...
as a substitute for the SI derived unit
SI derived unit
The International System of Units specifies a set of seven base units from which all other units of measurement are formed, by products of the powers of base units. These other units are called SI derived units, for example, the SI derived unit of area is square metre , and of density is...
W cm−2 sr−1 µm−1, or watt
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
s divided by centimeters squared, steradian
Steradian
The steradian is the SI unit of solid angle. It is used to describe two-dimensional angular spans in three-dimensional space, analogous to the way in which the radian describes angles in a plane...
s, and micrometers
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
.
This is primarily used as a unit of spectral radiance or sterance. While it started out used only in Lockheed, many in the radio astronomy field adopted its use.