Before the first Landsat (1972), perhaps the best examples of multispectral photographs were those taken by a four camera array mounted in the Apollo 9 (1968) spacecraft window. Skylab later used a six camera array.

### History of Remote Sensing: Apollo 9 Multispectral Images

The first multispectral photography from space happened during the famous 1968 Apollo 9 mission. Scientist mounted four Hasselblad cameras in a holder such that they all aimed at the same target point when an astronaut triggered their shutters simultaneously. Below are three filtered b & w photos of southern California around San Diego, which the astronauts took in the green, red, photo IR bands, and a (false) color IR picture.

Green | Red
Photo IR Bands | False Color IR

I-18: Note that clouds, snow on the mountains, and light desert soils (right center) all appear white in the false color composite image and the three black and white filter images. There are several areas of bright to medium red in the f.c. composite. Try to find their corresponding locations in the three filter images and be aware of their gray levels. Answers

A six-camera multispectral system flew on the Skylab spacecraft, which several crews occupied between May 1973 and February 1974. The photos they took helped show the value of multispectral photography to discipline scientists , particularly geologists, hydrologists, agronomists, foresters, and those concerned with environmental monitoring and land use and cover assessment.

Primary Author: Nicholas M. Short, Sr. email: nmshort@ptd.net