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First Pictures: Color View of the Earth & A Tropical Depression from Space – October 5, 1954

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While today we are inundated with color images of the Earth, our earliest views from space were confined to monochromatic or black and white images (see “First Pictures: The View of Earth from Space – October 24, 1946”). During the post war years when we began to explore the frontier of space, color photographic film was not sensitive enough, compared to black and white film of the era, requiring longer exposure times which tended to blur the resulting photographs. Combined with other technical issues, it was not until 1954 (eight years after the first space photographs of Earth were taken) that color film technology had advanced enough to make it possible to perform high altitude photography of the Earth from a fast moving rocket.

 

The Experiment

The person responsible for the first color photographs of the Earth taken from space was Dr. Otto Berg (1917-2017) then working at the Naval Research Laboratory (NRL). An astrophysicist by training, Dr. Berg was involved with high altitude research using surplus V-2, then later Aerobee sounding rockets, during the post war years. The Aerobee was originally designed and built for NRL by the Aerojet Engineering Corporation (which today is part of Aerojet Rocketdyne) under the guidance of the Applied Physics Laboratory at Johns Hopkins University.

Cutaway diagram showing the major components of the Aerobee sounding rocket. Click on image to enlarge. (NASM)

The initial design of what was officially designated RTV-N-8 called for a two-stage vehicle with a mass of 540 kilograms capable of hurling a 60 kilogram payload to an altitude of 125 kilometers. The main stage of the Aerobee was powered by a 12-kilonewton liquid propellant XASR-series engine burning the hypergolic propellant mixture of red fuming nitric acid (RFNA) as well as a 65:35 mix of aniline and furfuryl alcohol. The rocket was 5.74 meters long, excluding the payload, and 38 centimeters in diameter. It used a solid propellant booster stage at liftoff to provide 93 kilonewtons of thrust for 2.5 seconds to get the rocket traveling fast enough for its fins to provide stability during flight as it left its launch tower.

The first batch of 20 rockets was so successful that in 1952 the USAF and US Navy requested the development of improved versions of the Aerobee incorporating Aerojet’s new AJ-10-series engines. For the NRL-sponsored flight which would take the first color photographs of the Earth from space, a one-off variant of the Aerobee with improved performance, officially designated RTV-N-10b, was employed. Unlike the earlier RTV-N-10 which used an XASR-2 engine, the main stage of this version of the Aerobee used an Aerojet AJ-10-24 engine which generated almost 18 kilonewtons of thrust.

Here is a photograph of the sole Aerobee RTV-N-10b variant taken on October 1, 1954 – just four days before its flight which obtained the first color photographs of the Earth from space. (USN/WSMR Museum)

In order to secure photographs from the Aerobee to assess the usefulness of high altitude photography of the Earth, Dr. Berg included a pair of modified 16 mm movie cameras in the rocket’s payload each capable of taking 6 frames per second. The first camera used Kodak Super XX black and white film with a speed of ISO 200. It was fitted with a wide angle, f/4.5 lens providing a 90° field of view with an exposure time of 1/1500th of a second in order to minimizing blurring. The second camera, fitted with a semi-telephoto f/3.5 lens, used Kodachrome color film with 1/500th of a second exposure time. Earlier attempts at color photography of the Earth from space using sounding rockets were thwarted by the strong blue haze from Rayleigh scattering in Earth’s atmosphere which washed out the colors in the recorded scene. In order to reduce this problem, Dr. Berg fitted the color movie camera with a Wratten 2B filter. This pale yellow, longpass filter with a cutoff at a wavelength of 395 nm blocked the shortest blue and UV wavelengths in order to cut through the strong blue atmospheric haze.

 

The Flight & Afterwards

At 11:15 AM MST (18:15 GMT) on October 5, 1954, the Aerobee lifted off from its pad in the White Sands Proving Ground in New Mexico (today known as the White Sands Missile Range). With the pair of onboard cameras looking out from the side of the ascending rocket, they recorded the ascent as planned. As the Aerobee approached its 160-kilometer apogee, the slow spin of the rocket allowed strips of the Earth scene below to be photographed. Initially, the horizon was recorded but as the Aerobee ascended, its slowly increasing tilt allowed adjacent swaths of the scene to come into view until the cameras were almost looking straight down (as can be seen in the video below). During its descent, the cameras, which were mounted inside an armored container, were ejected and parachuted safely back to Earth where they were quickly recovered in good condition.

As Dr. Berg and his team inspected the films from their camera experiment, they found several hundred frames that were of excellent quality. The use of fast film, short exposure times and the color filter allowed the scene to be recorded in great detail with good color balance. A subset of 90 color frames acquired when the Aerobee was approaching apogee were selected for enlargement to create a large mosaic of the Earth below. Because the disk of the Earth subtended to an angle of about 155° at the 160-kilometer apogee height, the mosaic was assembled on a large sphere to take into account the distortions of such a wide effective field of view and subsequently rephotographed as shown below.

Here is the first color photo-mosaic of the Earth taken from space on October 5, 1954 as assembled by Dr. Otto Berg and his team. Click on image to enlarge. (NRL)

Here is a black and white context image of the view of Earth with major cities and geographical features labelled. The spiral shaped storm marked “Hurricane” is actually a tropical depression over the Big Bend region of Texas. Click on image to enlarge. (USN)

This spectacular, first of its kind color mosaic of the Earth as seen from space covered an area of about three million square kilometers stretching from Kansas City to Baja California with the horizon of the Earth some 1,400 kilometers distant. While the scene was dotted with cumulus and other cloud formations, by chance this color mosaic also captured a view of a spiral shaped tropical system over the Big Bend region of Texas. Labelled as a “hurricane” in the black and white context image above, this system started as a tropical depression off the coast of Cuba on October 2, 1954 and slowly moved westward over the Gulf of Mexico without noticeably intensifying beyond its surface winds of about 16 m/s. The system made landfall about 64 kilometers north of Brownsville, Texas on October 4 dropping 7.8 cm of rain on that city in just 45 minutes and over 15 cm in three hours. This unnamed storm was a weakening tropical depression when it was imaged by Dr. Berg and his team on October 5. Analysis of these images once again proved the value of imaging storms from space providing a vital prelude to the first weather satellite to be launched just 5½ years later (see “The First Weather Satellite”)

 

Related Reading

“First Pictures: The View of Earth from Space – October 24, 1946”, Drew Ex Machina, October 24, 2021 [Post]

“The First Weather Satellite”, Drew Ex Machina, April 1, 2015 [Post]

“First Pictures: Atlas 71D Color Photos of Earth from Space – October 13, 1960”, Drew Ex Machina, October 13, 2020 [Post]

 

General References

L.F. Hubert and Otto Berg, “A Rocket Portrait of a Tropical Storm”, Monthly Weather Review, Vol. 83, No. 6, pp. 119-124, June 1955

Jeremy Theoret, “First Color Photo of the Earth from Space Unearthed!”, Apollospace, February 6, 2023 [Post]

“A 100 Mile High Portrait of the Earth”, Life, Vol. 39, No. 10, pp. 10-11, September 5, 1955

 


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