As yet no observatory has obtained a direct image of an extrasolar planet. The vast majority are detected through the effect of their gravitational force on their parent stars. As the unseen planet orbits, the star shifts back and forth in space. The light of the star changes slightly, increasing and decreasing in wavelength due to the 'Doppler shift’.
Earth-like planets exert a much smaller force on stars than giant planets like Jupiter. The resulting Doppler shift is much smaller, making it much more difficult to find terrestrial planets. But within the next decade both ESA and NASA plan to use orbiting observatories to look for them.
On a side note: the "HD" in this star's designation stands for the Henry Draper Catalogue.
You can read about this pioneering 19-century astrophotographer HERE.
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