Mars seen by the Hubble Space Telescope. Photo: NASA/ESA/STScI

Seasonal flows of extremely salty water on Mars could be longer-lasting and more frequent than initially thought, though they likely aren't suitable to life as we know it, according to a study in the journal Nature Astronomy this week.

Why it matters: If these brines on the Red Planet are not habitable for microbes as we understand them, then scientists may not need to worry about potentially contaminating these regions during future missions, opening up new avenues of exploration on Mars.

What they found: Seasonal brines on Mars don't get warmer than about -55°F, a much colder temperature than life is known to thrive in.

  • Those liquids can form on about 40% of the Martian surface for as long as six hours, according to the study.

Yes, but: While the study shows it's unlikely that Earth-originating microbes could find safe purchase in Martian brines, that doesn't mean space agencies should send rovers to explore these parts of Mars from very close range.

  • It's still possible that some type of yet-to-be-discovered life on Earth could find a way to live in even this extreme environment on Mars.
  • "My hope is that our work motivates such further research into extremophiles on Earth," Edgard G. Rivera-Valentín, an author of the new study, told Axios via email.

Go deeper: Where to hunt for life on Mars

Go deeper

Jul 28, 2020 - Science

Perseverance will carry a Martian helicopter, other tech to the Red Planet

Artist's illustration of the Mars Ingenuity helicopter. Image: NASA/JPL-Caltech

Perseverance will carry new tech to Mars that represents major technological advances since NASA's last rover — Curiosity — landed on the Red Planet in 2012.

Why it matters: These new experiments and technology demonstrations will fill in gaps in knowledge scientists have about the world and set up future robotic missions in the process.

Updated 2 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 3 a.m. ET: 19,648,084 — Total deaths: 727,024 — Total recoveries — 11,941,723Map.
  2. U.S.: Total confirmed cases as of 3 a.m. ET: 4,998,105 — Total deaths: 162,425 — Total recoveries: 1,643,118 — Total tests: 61,080,587Map.
  3. Politics: Trump signs 4 executive actions on coronavirus aid — Democrats, and some Republicans, criticize the move
  4. Public health: Fauci says chances are "not great" that COVID-19 vaccine will be 98% effective — 1 in 3 Americans would decline COVID-19 vaccine.
  5. Science: Indoor air is the next coronavirus frontline.
  6. Schools: How back-to-school is playing out in the South as coronavirus rages on — Princeton, Johns Hopkins, Howard to hold fall classes online.
Updated 3 hours ago - World

Brazil coronavirus death toll tops 100,000 and case numbers surpass 3 million

Brazilian President Jair Bolsonaro posted a photo of himself to Facebook congratulating his soccer team, Palmeiras, for winning the state title Saturday, moments after the health ministry confirmed the national COVID-19 death toll had surpassed 100,000.

Why it matters: Brazil is only the second country to confirm more than 100,000 deaths from the coronavirus. On Sunday morning, it became the second country to surpass 3 million cases, per Johns Hopkins. Only the U.S. has reported more. Bolsonaro has yet to address the milestones. He has previously tested positive for COVID-19 three times, but he's downplayed the impact of the virus, which has crippled Brazil's economy.

Editor's note: This article has been updated with the latest coronavirus case numbers and more context.