  Multispacecraft and multiwavelength observations of solar eruptions such as
flares and coronal mass ejections are essential to understand the complex
processes behind these events. The study of solar burst events in the
radio-frequency spectrum has relied almost exclusively on data from
ground-based observations and a few dedicated heliophysics missions such as
STEREO or Wind. Reanalysing existing data from the Mars Reconnaissance Orbiter
(MRO) Shallow Radar (SHARAD) instrument, a Martian planetary radar sounder, we
have discovered the instrument was also capable of detecting solar radio
bursts, and was able to do so with unprecedented resolution for a space-based
solar instrument. In this study we aim at demonstrating the reliability and
value of SHARAD as a new solar radio-observatory. We characterised the
sensitivity of the instrument to type-III solar radio bursts through a
statistical analysis of correlated observations, using STEREO and Wind as
references. Using 38 correlated detections, we establish the conditions under
which SHARAD can observe solar bursts in terms of acquisition geometry. As an
example of scientific application, we also present the first analysis of
type-III characteristic times at high resolution beyond 1 AU. A simple logistic
model based purely on geometrical acquisition parameters can predict burst show
vs. no-show in SHARAD data with an accuracy of 79.2%, demonstrating the
reliability of the instrument for detecting solar bursts and laying the
foundation for using SHARAD as a solar radio-observatory. The extremely high
resolution of the instrument, both in temporal and frequency directions, its
bandwidth, and its position in the solar system enable SHARAD to make
significant contributions to heliophysics; it could inform on plasma processes
on the site of the burst generation and along the propagation path of
associated fast electron beams.
