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Selfie by NASA's rover Opportunity on Mars in 2011, showing dust covering the solar panels.

NASA’s Opportunity rover took this self-portrait in January 2014; a thick layer of dust is covering its solar panels.Credit: NASA/JPL-Caltech/Cornell/Arizona State Univ.

Opportunity lost: Goodbye to pioneering Mars rover

Opportunity’s mission is officially over. NASA’s Mars rover far exceeded its original 90-day mission, ultimately spending 15 years exploring the Meridiani Planum region of the planet. NASA had not heard from Opportunity since 10 June 2018, when a massive dust storm blocked the rover’s solar panels. With the passage of the windy season — which scientists had hoped might clear the panels — Opportunity now faces certain death in the deep freeze of a Martian winter.

Nature | 3 min read

BY THE NUMBERS

• Mission duration that Opportunity was designed for: 90 days and 1,000 metres

• Mission completed: almost 15 years and more than 45 kilometres

• Mars record for longest 1-day distance travelled: 220 metres, on 20 March 2005

• Images sent back to Earth: more than 217,000, including 15 360-degree colour panoramas

• Weeks spent stuck in the sand in 2005: nearly five

Human cells reprogrammed to create insulin

Researchers have coaxed human pancreatic cells that don’t normally make insulin to change their identity and begin producing the hormone. When implanted into mice, these reprogrammed cells relieved symptoms of diabetes, raising the possibility that the method could one day be used as a treatment for people.

Nature | 5 min read

Reference: Nature paper

Biological sex affects how cancer tumours evolve

If you have cancer, your sex can affect the number and types of mutation lurking in your tumours. A genomic analysis spanning nearly 2,000 tumours and 28 types of cancer adds to a growing realization that sex is important in cancer, and not only because of lifestyle differences. “We were expecting differences in the number of mutations, not the type,” says geneticist Paul Boutros. “For example, women might be more affected by tobacco smoke than men. We didn’t expect a new process.”

Nature | 5 min read

Reference: bioRxiv preprint

FEATURES & OPINION

What 50 PIs taught me about why I didn’t get tenure

Biochemist Bela Schmidt’s quest to understand an all-too-familiar career setback can be distilled into eight pieces of advice. From making a career plan to treating your supervisors as future colleagues, he offers tips to put you in the best position for success.

Nature | 10 min read

Three secrets of survival for science advisers

Science advisers offer essential independent, impartial expertise to legislators — but in some countries, their offices are being shuttered. Policy specialists Chris Tyler and Karen Akerlof look at successes and failures from across the globe, and find that impartiality, humbleness and providing good value for money are key to survival.

Nature | 10 min read

Nature editors review Ladybird books

The Ladybird Experts book series offers to summarize serious science in the impish style of the beloved retro children’s books. But how well do Britain’s top TV boffins explain topics such as quantum mechanics, artificial intelligence and bubbles? Pretty well, find editors from the Nature journals in their reviews of the pocket-sized publications.

Nature Ecology & Evolution Community | 22 min read

QUOTE OF THE DAY

“My battery is low and it’s getting dark.”

Science journalist Jacob Margolis paraphrases the last words of the Opportunity Mars rover to NASA Jet Propulsion Lab scientists. (Twitter)