Question

Most of the exoplanets we have found to date are:

a) larger than Earth, with longer orbital periods.
b) smaller than Earth, with longer orbital periods.
c) about the same size as Earth, with about the same orbital period.
d) larger than Earth, with shorter orbital periods.
e) smaller than Earth, with shorter periods.

Answer 1

Most exoplanets discovered to date are larger than Earth which is an observational bias of current detection technology like the Doppler and transit methods.

Step-by-step explanation:

Most of the exoplanets we have found to date are larger than Earth, which reflects an observational bias because smaller planets are more difficult to detect. This is partly due to the sensitivity and limitations of our current detection techniques, including the Doppler and transit methods, which are better at finding planets that are of a significant size and gravitational influence. The Kepler mission, while it has discovered a large number of exoplanets, was limited to detections of planets with orbital periods of less than 400 days and sizes larger than Mars. Interestingly, although Kepler has found that planets like Earth might be the most common type of planet, it encounters an observational limit in detecting very small planets due to the technical difficulty of observing their transits.