ATS-2 (

Applications Technology Satellite The Applications Technology Satellites (ATS) were a series of experimental satellites launched by NASA, under the supervision of, among others, Wernher von Braun. The program was launched in 1966 to test the feasibility of placing a satellite i ...

) was a

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. C ...

launched by NASA on April 6, 1967, on an

Atlas-Agena The Atlas-Agena was an American expendable launch system derived from the SM-65 Atlas missile. It was a member of the Atlas family of rockets, and was launched 109 times between 1960 and 1978. It was used to launch the first five Mariner uncrew ...

rocket A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely fr ...

from

Cape Canaveral , image = cape canaveral.jpg , image_size = 300 , caption = View of Cape Canaveral from space in 1991 , map = Florida#USA , map_width = 300 , type =Cape , map_caption = Location in Florida , location ...

Objectives

The ATS-2 had the following objectives: test new concepts in spacecraft design, propulsion and stabilization; capture high quality images of cloud cover; collect data measurements in an aerospace environment; and test improved communication systems.

Features

The satellite had a cylindrical shape with a diameter and a height of . After including the motor cover, the satellite was about tall. The surface of the satellite was covered by

solar panel A solar cell panel, solar electric panel, photo-voltaic (PV) module, PV panel or solar panel is an assembly of photovoltaic solar cells mounted in a (usually rectangular) frame, and a neatly organised collection of PV panels is called a photo ...

s, and it utilized

gravity-gradient stabilization Gravity-gradient stabilization (a.k.a. "tidal stabilization") is a method of stabilizing artificial satellites or space tethers in a fixed orientation using only the orbited body's mass distribution and gravitational field. The main advantage ove ...

for control.

Experiments

The following 12 experiments were conducted: *

Radio astronomy Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation comin ...

* Magnetospheric electric fields * Electron magnetic spectrometer deflection * Particle telescope * Omnidirectional proton and electron detectors * Very low frequency (VLF) receiver * Earth's

albedo Albedo (; ) is the measure of the diffuse reflection of solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that refl ...

( DoD) * Microwave communication transponder (Hughes Co.) * Gravity-Gradient Stabilization (General Electric Co) * Advanced Vidicon Camera System (AVCS) * Thermal coating degradation * Solar cell degradation

Mission

The launch of ATS-2 went entirely according to plan up to the first Agena burn. When the second burn was initiated, the Agena engine failed to restart and thus the satellite could not be placed in the correct orbit. Postflight investigation found that the oxidizer isolation valve had failed to close after the first burn. This valve was supposed to prevent propellant from escaping the tanks and filling the turbopump during the coasting phase, but since it remained open, the pump developed vapor lock and thus it became impossible to pump oxidizer in. A tiny amount of ISP was generated by the gas generator igniter cartridge. The low periapsis of the orbit caused the satellite to tumble more than the stabilization system could compensate, which complicated its mission. The satellite still produced some usable data from the experiments, most notably those regarding cosmic rays and particles. It reentered the

atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...

on September 2, 1969.

References

External links

ATS, Past NASA Missions

ATS, NASA Science Missions
{{Orbital launches in 1967 1967 in spaceflight NASA satellites orbiting Earth Applications Technology Satellites