The Effects of Atmospheric Turbulence on Simulated Starlight in a Low-Pressure Telescope Environment

We investigated the feasibility of using nulling interferometry techniques in the stratosphere to search for extra-solar planets. Studies have shown wavefront distortions from atmospheric turbulence to be too large to obtain clear ground-based images. Wavefront errors caused by atmospheric turbulence in the stratosphere are on the scale of 1 angstrom [4], however, the level of the wavefront error inside a telescope tube is unknown. We used Kite, a system level testbed created by the Jet Propulsion Laboratory for the External Metrology System of the Space Interferometry Mission, to simulate atmospheric turbulence conditions inside a telescope tube in the stratosphere. We obtained 40 minutes of laser metrology gauge readings in relatively stabilized temperatures at 5 mb. The data was analyzed using adaptive optics and blanking techniques to reduce the level of instrument noise. The integrated total error was approximately 1.849 angstroms, validating the possibility of applying nulling interferometry techniques without sending a telescope into space.