LangbasenInterferometrie

LangbasenInterferometrie, or long-baseline interferometry, is a technique in observational astronomy that combines light collected by two or more telescopes separated by large distances. By coherently correlating the incoming wavefronts, the method synthesizes a telescope with an aperture equal to the baseline, dramatically increasing angular resolution compared with any single telescope.

In practice, light beams from the individual telescopes are brought together with precise path-length control to within a fraction of a wavelength. The resulting interference fringes are measured as a function of baseline and time. Each measurement samples a point in the source's Fourier transform (the uv plane); imaging is performed by combining many samples through aperture synthesis and careful calibration.

Optical and infrared implementations contend with atmospheric turbulence, requiring fringe tracking, adaptive optics, and bright calibrators, while radio interferometry relies on stable electronics and long baselines. LangbasenInterferometrie thus spans both optical/IR and radio regimes, using different technical solutions to achieve coherence over large distances.

LangbasenInterferometrie has enabled direct measurements of stellar diameters, surface features on evolved stars, imaging of binary systems, protoplanetary disks, and compact regions in active galactic nuclei. Notable facilities include optical/IR arrays such as the Very Large Telescope Interferometer (VLTI) and the CHARA Array, as well as radio Very Long Baseline Interferometry (VLBI) networks.

Challenges include sensitivity limits, complex data reduction, calibration demands, and phase errors from the atmosphere or instruments. Despite these, long-baseline interferometry remains a cornerstone of high-resolution astronomy, complementing direct imaging and other high-resolution techniques.