Impenetrable ice, Mars rumbles and nuclear-fusion lab

20 MARCH 2019
Impenetrable ice, Mars rumbles and nuclear-fusion lab
The week in science: 15–21 March 2019.

EVENTS
Thick ice thwarts Antarctic mission Thick sea ice has halted plans to explore a unique polar ecosystem in the Southern Ocean that was revealed when a giant iceberg calved from the Antarctic Peninsula in 2017. An international science team on board the German research ice-breaker RV Polarstern (pictured) had set off for the Larsen C ice shelf from Chile on 18 February. The ship navigated the Antarctic waters at the tip of the peninsula, but encountered dense sea ice to the east, in the Weddell Sea. After a week of fruitless attempts to find a route, Polarstern’s captain abandoned plans made earlier this month to sail farther south towards Larsen C. The research teams agreed to do alternative fieldwork in more-accessible regions. It is the third time that an expedition has failed to reach the calving site. Towering sea ice stopped a British Antarctic Survey team from getting there in February last year. A South African vessel retrieved ice samples about 200?kilometres north of the site before turning back in January.



German research icebreaker Polarstern has struggled to navigate thick sea ice near Antarctica.Credit: Ingo Arndt/Minden/Getty

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Mars rumbles NASA’s Mars InSight lander has measured low-frequency rumbles, known as infrasound, produced by weather systems passing above the spacecraft. It is the first time that infrasound has been detected on Mars, Philippe Lognonné of the Paris Institute of Earth Physics told the Lunar and Planetary Science Conference in The Woodlands, Texas, on 18 March. InSight landed last November in a region known as Elysium Planitia, and placed a seismometer on the surface. This picked up the infrasound rumbling, but has yet to detect ground shaking from a marsquake, which scientists hope will tell them about the red planet’s interior.

More:
https://www.nature.com/articles/d41586-019-00877-5