  Discovering an Earth-like exoplanet in habitable zone is an important
milestone for astronomers in search of extra-terrestrial life. While the radial
velocity (RV) technique remains one the most powerful tools in detecting and
characterizing exo-planetary sys- tems, we calculate the uncertainties in
precision RV measurements considering stellar spectral quality factors, RV
calibration sources, stellar noise and telluric contamination in different
observational bandpasses and for different spectral types. We predict the
optimal observational bandpass for different spectral types using the RV
technique un- der a variety of conditions. We compare the RV signal of an
Earth-like planet in the habitable zone (HZ) to the near future state of the
art RV precision and attempt to answer the question: How close are we to
detecting Earth-like planet in the HZ using the RV technique?
