A seismic tremor on Mars has been detected by NASA’s Insight. Initial analysis of the tremor has confirmed that it originated from inside the planet and not due to atmospheric disturbances such as winds.
This breakthrough came five months after robotic probe InSight, which has been designed specifically for studying the interior regions of planets, landed on Mars for a two-year seismological mission. There are a number of instruments in InSight for measuring different properties of a planet’s surface such as its temperature, rotation. It has been manufactured by Lockheed Martin and NASA’s Jet Propulsion Laboratory manages it. The main objectives of InSight are to put a seismometer on Mars’ surface which can not only help in measuring seismic activity but also generate exact 3D models of the interior surfaces of Mars.
Till now most of the sample collected by the Seismic Experiment for Interior Structure (SEIS) instrument consisted of background noise, but on April 6, the instrument recorded seismic tremors for the first time. Scientists naturally were quite excited for this moment as they had to wait for several months to obtain this signal. Philippe Lognonné, team head of SEIS reported that the scientific community is quite excited to have evidence that Mars is active seismically.
The seismic waves on propagation through a planet often slow down as they strike different types of materials. This helps the researchers get a clear picture of the internal structure and composition of the planet. However, the signal Sol 128 was very weak and hence scientists could not deduce much about the interior of Mars. Although Mars is not active tectonically, this signal indicates that there is seismic activity on Mars.
The signal Sol 128 has a resemblance to that of the seismic profiles of the moonquakes which were detected with the help of seismometers placed on the surface of the moon by the astronauts who went on the historic Apollo missions.
The moon similar to Mars is not active tectonically but seismic activity has been recorded there. This is due to the slow shrinking of the Moon’s interior surface which has been occurring since it was formed about 5 billion years ago. Due to the shrinking of the interior, stresses are produced on the outer crust until there is a crack, causing tremors.
Scientists believe that similar processes occur in Mars. Bruce Banerdt, head investigator of InSight reported that although they have been gathering background noise for some time, this event has officially led to a new field of research, Martian seismology.