Eerie, mysterious ‘dinks and donks’ deep within Mars revealed by NASA lander

2 Oct 2019

The InSight lander’s dome-covered seismometer, known as SEIS, on Mars. Image: NASA/JPL-Caltech via AP

NASA’s InSight lander has revealed the sounds of ‘marsquakes’ deep within the planet, but also some truly eerie, mysterious sounds.

NASA’s InSight lander on Mars has captured the low rumble of so-called ‘marsquakes’ and a symphony of other otherworldly sounds. Scientists released an audio sampling on Tuesday. The sounds had to be enhanced for humans to hear.

InSight’s seismometer has detected more than 100 events, but only 21 are considered strong marsquake candidates. The rest could be marsquakes — or something else.

The French seismometer is so sensitive it can hear the Martian wind as well as movements by the lander’s robot arm and other mechanical “dinks and donks”, as the team calls them. These sounds have mostly been heard during the evening.

In trying to explain them, NASA said that they’re coming from delicate parts of the seismometer and that it could be from their expansion and contraction against one another through heat loss. This is similar to when a car engine makes ticking noises after it has been turned off and begins cooling.

A mix between Earth and the moon

“It’s been exciting, especially in the beginning, hearing the first vibrations from the lander,” said Imperial College London’s Constantinos Charalambous, who helped provide the audio recordings.

“You’re imagining what’s really happening on Mars as InSight sits on the open landscape,” he added in a statement.

The recordings released by NASA suggest that the planet’s crust is similar to a mix between the Earth’s and the moon’s. On Earth, cracks in the planet’s crust eventually seal over time as water flows into them along with new minerals. This, the space agency said, allows the sound waves to flow uninterrupted through the old fractures.

InSight arrived on Mars last November and recorded its first seismic rumbling in April. A German drilling instrument, meanwhile, has been inactive for months.

Scientists are trying to salvage the experiment to measure the planet’s internal temperature. The so-called mole is meant to penetrate five metres beneath the Martian surface, but has managed barely 300cm.

Researchers suspect the Martian sand is not providing the necessary friction for digging, causing the mole to helplessly bounce around rather than burrow deeper and to form a wide pit around itself.

– PA Media, with additional reporting by Colm Gorey