A Sense of Doubt blog post #1702 - Life on Mars: maybe? Rivers: Yes! And elsewhere...
Just sharing.
But what more is there to say than life on others planets, even Mars?
LOW POWER MODE: I sometimes put the blog in what I call LOW POWER MODE. If you see this note, the blog is operating like a sleeping computer, maintaining static memory, but making no new computations. If I am in low power mode, it's because I do not have time to do much that's inventive, original, or even substantive on the blog. This means I am posting straight shares, limited content posts, reprints, often something qualifying for the THAT ONE THING category and other easy to make posts to keep me daily. That's the deal. Thanks for reading.
https://science.slashdot.org/story/19/10/14/0350210/nasa-consultant-convinced-we-found-evidence-of-life-on-mars-in-the-1970s
NASA Consultant 'Convinced We Found Evidence of Life on Mars in the 1970s' (ibtimes.com)
"A consultant for NASA slammed the agency for deliberately ignoring the results of the experiment he handled that showed signs of alien life on Mars," reports the International Business Times. "According to the consultant, NASA refuses to conduct new life-detection tests on the Red Planet."Engineer Gilbert Levin served as a principal investigator on NASA's Viking missions, which sent two identical landers to Mars. For his role, Levin handled the missions' biological experiments known as Labeled Release (LR). These experiments focused on identifying living microorganisms on Mars. The experiments were sent to the Red Planet through the Viking 1 and Viking 2 missions in 1975....
"As the experiment progressed, a total of four positive results, supported by five varied controls, streamed down from the twin Viking spacecraft landed some 4,000 miles apart," Levin wrote in Scientific American. "The data curves signaled the detection of microbial respiration on the Red Planet," he continued. "The curves from Mars were similar to those produced by LR tests of soils on Earth. It seemed we had answered that ultimate question."
Despite the results of the LR experiment, the findings were discarded by NASA due to the agency's previous experiment on Mars.
More from Levin's article in Scientific American:Life on Mars seemed a long shot. On the other hand, it would take a near miracle for Mars to be sterile. NASA scientist Chris McKay once said that Mars and Earth have been "swapping spit" for billions of years, meaning that, when either planet is hit by comets or large meteorites, some ejecta shoot into space. A tiny fraction of this material eventually lands on the other planet, perhaps infecting it with microbiological hitch-hikers.
"As the experiment progressed, a total of four positive results, supported by five varied controls, streamed down from the twin Viking spacecraft landed some 4,000 miles apart," Levin wrote in Scientific American. "The data curves signaled the detection of microbial respiration on the Red Planet," he continued. "The curves from Mars were similar to those produced by LR tests of soils on Earth. It seemed we had answered that ultimate question."
Despite the results of the LR experiment, the findings were discarded by NASA due to the agency's previous experiment on Mars.
More from Levin's article in Scientific American:Life on Mars seemed a long shot. On the other hand, it would take a near miracle for Mars to be sterile. NASA scientist Chris McKay once said that Mars and Earth have been "swapping spit" for billions of years, meaning that, when either planet is hit by comets or large meteorites, some ejecta shoot into space. A tiny fraction of this material eventually lands on the other planet, perhaps infecting it with microbiological hitch-hikers.
https://science.slashdot.org/story/19/03/28/2343206/mars-had-big-rivers-for-billions-of-years-study-suggests
Mars Had Big Rivers For Billions of Years, Study Suggests (space.com)
A new study suggests that Mars once had giant rivers larger than anything on Earth after the planet lost most of its atmosphere to space. "That great thinning, which was driven by air-stripping solar particles, was mostly complete by 3.7 billion years ago, leaving Mars with an atmosphere far wispier than Earth's," reports Space.com. "But Martian rivers likely didn't totally dry out until less than 1 billion years ago, the new study found." From the report:"We can start to see that Mars didn't just have one wet period early in its history and then dried out," study lead author Edwin Kite, an assistant professor of geophysical sciences at the University of Chicago, told Space.com. "It's more complicated than that; there were multiple wet periods." The team's work suggests that Martian rivers flowed intermittently but intensely over much of the planet's 4.5-billion-year history, driven by precipitation-fed runoff. The rivers' impressive width -- in many cases, more than twice that of comparable Earth catchments -- is a testament to that intensity.
It's unclear how much water Martian rivers carried, because their depth is hard to estimate. Determining depth generally requires up-close analysis of riverbed rocks and pebbles, Kite said, and such work has only been done in a few locations on Mars, such as Gale Crater, which NASA's Curiosity rover has been exploring since 2012. The ancient Mars rivers didn't flow in just a few favored spots; rather, they were distributed widely around the planet, Kite and his colleagues found.
It's unclear how much water Martian rivers carried, because their depth is hard to estimate. Determining depth generally requires up-close analysis of riverbed rocks and pebbles, Kite said, and such work has only been done in a few locations on Mars, such as Gale Crater, which NASA's Curiosity rover has been exploring since 2012. The ancient Mars rivers didn't flow in just a few favored spots; rather, they were distributed widely around the planet, Kite and his colleagues found.
Earth-Like Planets May Be Common Outside Our Solar System, Scientists Discover (vice.com)
Scientists have directly observed the rocky guts of exoplanets, which are worlds from different star systems, by watching the fallout of these objects crashing into the corpses of dead stars. From a report:This mind-boggling technique has revealed that exoplanets are similar in composition to planets in our own solar system, implying that worlds like Earth may be plentiful in our galaxy, according to a study published on Thursday in Science. "It's pretty cool because this is really the only way to measure the geochemistry of exoplanetary bodies directly," said lead author Alexandra Doyle, a graduate student of geochemistry and astrochemistry at UCLA, in a phone call. Co-author Edward Young, a professor of geochemistry and cosmochemistry at UCLA, added that the study represents "the first time such an advanced way of looking at the geochemistry of these bodies has been used," in the same call.
We are living through a golden age of exoplanet discoveries. Thousands of exoplanets have been detected, including an Earth-sized world orbiting the closest star to the Sun. But it is still extremely difficult to capture details about the interior composition and dynamics of these worlds. Unlike other planetary properties such as mass or atmospheric composition, a planet's geochemistry cannot be deduced just by looking at an object passing in front of its host star. White dwarfs, as it turns out, can help plug this information gap. These objects are the remains of stars that have blown up and collapsed into tiny, dense spheres about the size of Earth (our own Sun will embark on this transition in about five billion years). The pyrotechnic deaths of these stars scramble the orbits of many objects in our solar system, such as asteroids and planets. Some of these worlds may end up hurtling toward the star's posthumous white dwarf, which tears them apart over the course of about 100,000 to one million years.
We are living through a golden age of exoplanet discoveries. Thousands of exoplanets have been detected, including an Earth-sized world orbiting the closest star to the Sun. But it is still extremely difficult to capture details about the interior composition and dynamics of these worlds. Unlike other planetary properties such as mass or atmospheric composition, a planet's geochemistry cannot be deduced just by looking at an object passing in front of its host star. White dwarfs, as it turns out, can help plug this information gap. These objects are the remains of stars that have blown up and collapsed into tiny, dense spheres about the size of Earth (our own Sun will embark on this transition in about five billion years). The pyrotechnic deaths of these stars scramble the orbits of many objects in our solar system, such as asteroids and planets. Some of these worlds may end up hurtling toward the star's posthumous white dwarf, which tears them apart over the course of about 100,000 to one million years.
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- Bloggery committed by chris tower - 1910.16 - 10:10
- Days ago = 1565 days ago
- New note - On 1807.06, I ceased daily transmission of my Hey Mom feature after three years of daily conversations. I plan to continue Hey Mom posts at least twice per week but will continue to post the days since ("Days Ago") count on my blog each day. The blog entry numbering in the title has changed to reflect total Sense of Doubt posts since I began the blog on 0705.04, which include Hey Mom posts, Daily Bowie posts, and Sense of Doubt posts. Hey Mom posts will still be numbered sequentially. New Hey Mom posts will use the same format as all the other Hey Mom posts; all other posts will feature this format seen here.
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