Long Duration Exposure Facility
(LDEF) Archive System

NASA Langley Research Center
Hampton, Virginia

Experiments

Langley Home Page
Space Environments &Technology Archive System Home Page
Space Environments &Effects Home Page
NASA Home Page

If you would like to receive further information on SETAS, or have suggestions on what information you would like to see accessible through this archive, please fill out the SETAS request form.
SETAS Request Information
Last Update: February 10, 1998

Comments and Question concerning this WEB Page should be directed to Thomas H. See or Claire Dardano
Experiment: AO139A

Experiment Title: Growth of Crystals From Solutions in Low Gravity

Original Principal Investigator(s): Nielsen, Dr. Kjeld Flemming - Invest. Role: Original, Nielsen, Dr. Kjeld Flemming - Invest. Role: Present, Lind, David - Invest. Role: Original, Lind, David - Invest. Role: Present,

Experiment Description:

These crystal growth experiments are an extension of preliminary experiments performed during the Apollo-Soyuz Test Project flight and similar experiments for a Spacelab flight. Following the crystal growth experiments with unidirectional conductors on the European Spacelab by K.F. Nielsen and the Apollo-Soyuz investigations on room temperature solute diffusion crystal growth by M.D. Lind, it was decided by both investigators to share what was later named experiment AO139A on the LDEF. The crystal growth method used consisted of allowing two or more reactant solutions to diffuse slowly toward each other into a region of pure solvent, in which they react chemically to form single crystals of a desired substance. This method depends on suppression of convection and sedimentation. Suppression of convection should also eliminate the microscopic compositional fluctuations often caused by time-dependent convection in crystal growth systems. In many cases, convection and sedimentation can be completely eliminated only under the conditions of continuous low gravity attained during orbital space flight. Ideally, this type of crystal growth process requires that a low level of gravity (less than 0.0004 g) be maintained for a period of weeks or months. The LDEF flights were the only space flights planned that fully satisfy this requirement.

Associated Tray(s) Tray Location: G06 - Orientation: Earth-facing end

Photograph Classification: Flight

Associated Photograph(s):
LaRC - L90-10391
KSC - None
JSC - S32-76-066
LaRC - L89-04391
KSC - KSC-384C-256.02
JSC - None
LaRC - L91-11642
KSC - KSC-390C-1704.05
JSC - None


Back to Experiments Page

LDEF Archive System Home Page