spaceconnect logo

Earth and Mars ‘tug of war’ warms planet every 2.4m years

Researchers from the University of Sydney have discovered that the “gravitational tug of war” between Earth and Mars is linked to the global warming of our planet every 2.4 million years.

The previously undiscovered cycle speeds up deep ocean circulation and was revealed by analysing half a century of scientific drilling data from hundreds of sites worldwide.

The study’s results have been published in Nature Communications, following a collaboration with scientists at Sorbonne University in Paris.

Co-author Professor Dietmar Müller will appear on the Space Connect Podcast this week to discuss the findings in detail.


Writing in The Conversation, he explained, “Scientific ocean drilling data collected since the 1960s have generated a treasure trove of information on deep-sea sediments through time across the global ocean.

“In our study, we used sedimentary sequences from more than 200 drill sites to discover a previously unknown connection between the changing orbits of Earth and Mars, past global warming cycles, and the speeding up of deep-ocean currents.

“Most studies focus on complete, high-resolution records to detect climate cycles. Instead, we concentrated on the parts of the sedimentary record that are missing – breaks in sedimentation called hiatuses.

“A deep-sea hiatus indicates the action of vigorous bottom currents that eroded seafloor sediment. In contrast, continuous sediment accumulation indicates calmer conditions.


“Analysing the timing of hiatus periods across the global ocean, we identified hiatus cycles over the past 65 million years.

“The results show that the vigour of deep-sea currents waxes and wanes in 2.4 million-year cycles, coinciding with changes in the shape of Earth’s orbit.

“Astronomical models suggest the interaction of Earth and Mars drives a 2.4-million-year cycle of more sunlight and warmer climate alternating with less sunlight and cooler climate. The warmer periods correlate with more deep-sea hiatuses, related to more vigorous deep-ocean currents.”

Adam Thorn

Adam Thorn

Adam is a journalist who has worked for more than 40 prestigious media brands in the UK and Australia. Since 2005, his varied career has included stints as a reporter, copy editor, feature writer and editor for publications as diverse as Fleet Street newspaper The Sunday Times, fashion bible Jones, media and marketing website Mumbrella as well as lifestyle magazines such as GQ, Woman’s Weekly, Men’s Health and Loaded. He joined Momentum Media in early 2020 and currently writes for Australian Aviation and World of Aviation.

Receive the latest developments and updates on Australia’s space industry direct to your inbox. Subscribe today to Space Connect here.

Receive the latest developments and updates on Australia’s space industry direct to your inbox. Subscribe today to Space Connect.