Edit: It’s about the physicists, don’t @ me
Edit: It’s about the physicists, don’t @ me
“Both Mars and Earth had early atmospheres that were heavy, massive, and extraordinarily rich in CO2. While Earth’s carbon dioxide got absorbed into the oceans and locked up into carbonate rocks, Mars was unable to do the same, as its oceans were too acidified. The presence of sulfur dioxide led to Martian oceans that were rich in sulfuric acid. This led to geology of Mars we’ve discovered with rovers and landers, and pointed to a different cause — the solar wind — as the culprit in the mystery of the missing Martian atmosphere.
Thanks to NASA’s MAVEN mission, we’ve confirmed that this story is, in fact, the way it happened. Some four billion years ago, the core of Mars became inactive, its magnetic field disappeared, and the solar wind stripped the atmosphere away. With our magnetic field intact, our planet will remain blue and alive for the foreseeable future. But for a smaller world like Mars, its time ran out long ago. At last, we finally know why.”
For most of the 20th century, we knew that Earth had a carbon dioxide-rich past for its atmosphere, but that those atmospheric molecules were deposited into the ocean and precipitated or fossilized out as carbonate rocks like limestone and dolomite. We assumed that Mars, which once had a thick atmosphere and a water-rich surface, lost its atmosphere the same way. But landers and rovers changed all of that, discovering very little in the way of carbonate rocks, meaning that there must have been a different process at play to strip the Martian atmosphere away.
“In 2020, two next-generation rovers will launch: ESA’s ExoMars and NASA’s Mars 2020. Instead of indirect inferences and possibilities, we’ll actually be able to understand whether the origin of these molecules is geological or biological in nature. It’s important to keep an open mind and let science, rather than our hopes or fears, decide the answer. The evidence is building, and we’re finally gaining a more robust picture of how, exactly, Mars works.
It’s producing methane seasonally, contains loads of carbon-based compounds, and had a very watery past. But does that all add up to life, past or present? In 2018, the evidence doesn’t say “yes” just yet. But in just a few years, we just might have the answer. In a few years, for the first time, we might finally know if there’s life beyond Earth.”
We use the word “organics” a lot when we talk about life (and molecules) beyond Earth. But while that word may conjure up images of reproducing molecules, new cells, and life, the scientific definition is far more mundane: a molecule containing carbon. That means carbon monoxide and cyanide are organic, even though they may be toxic to life itself. The discovery of seasonally-varying methane on Mars is interesting, but it may be better evidence for something geologically compelling than it is for anything biological. Regardless of how you interpret it, one thing is for certain: everything we’ve found on Mars so far is not yet enough to claim evidence for life.
“5.) Maps of what’s happening and where. This is perhaps the greatest resource for determining what’s occurring and where. They show fissures and flows, including present, recent, and past lava flows. They display thermal maps of the fissure system and the lava flows that have occurred, overlaid atop satellite imagery. Occasionally, they have radar images that show how things like the eruptive vent at the summit has changed over the past few weeks. Most importantly, they have updated flow fronts, lava pools, lava channels, and ocean entry points. This way, you can know not only where the lava is at any moment, but where the lava flows are headed, and how that’s changed over time.”
On May 3rd, 2018, new cracks and fissures opened up around Kilauea on the Big Island of Hawaii, creating new flows and channels of lava. The next day, a magnitude 6.9 earthquake occurred: the largest in Hawaii in over 40 years. Since then the Kilauea eruption has intensified to rival its highest levels of the past century, with dangers coming from lava flows, channels, and fountains, vog and noxious gases, and volcanic ash. Despite these incredible dangers, however, there’s little worry that this will become as disastrous or deadly as the legendary 1790 eruption, despite the fact that hundreds of times as many people live on Hawaii now as did back then. Why? The incredible work of the USGS Hawaiian Volcano Observatory in collecting and disseminating information.
“Every few months, a volcanic eruption occurs on Earth, with lava flows and enormous plumes of volcanic ash. These small eruptions might produce only ~0.01 cubic kilometers of ash, while large, rare ones can produce thousands. Unlike the result of combustion, however, what we call volcanic ash isn’t ash at all.”
When you burn something like wood, coal, oil, or gas, the ash you produce is whatever’s left after the combustion reaction, combining the fuel with oxygen in the presence of heat, is complete. That type of ash can easily be washed away and, although it has a number of reuses, is fairly easy to clean up. But volcanic ash is fundamentally different. Instead of a product of combustion, it’s made of very small, often microscopic particles of rock, glass, or minerals. It’s produced when magma or the gases trapped within it reach the atmosphere and rapidly expand. When ashfall occurs, the consequences are not only extraordinary, but the hazards and cleanup are extraordinarily different from when combustive ashfall occurs.
“Volcanic lightning appears to occur most frequently around volcanoes with large ash plumes, particularly during active stages of the eruption, where flowing, molten lava creates the largest temperature gradients. The phenomena of lightning has been exquisitely recorded around a number of recent volcanic eruptions, including Iceland’s Eyjafjallajökull, Japan’s Sakurajima, Italy’s Mt. Etna, and Chile’s Puyehue, Calbuco and Chaiten volcanoes. But what you may not know is this phenomenon was not only captured during Mt. Vesuvius’ last eruption in 1944, but was accurately described nearly 2,000 years ago when it erupted all the way back in the year 79!”
Volcanoes are some of the most potentially destructive natural phenomena known to occur on our world. The most violent eruptions feature not only lava, but soot, ash, volatile gases, and even enormous chunks of rock hurled great distances. What you might not realize, however, is just how frequently these eruptions are accompanied by another spectacular show: volcanic lightning. Lightning isn’t only found in thunderstorms or other great electrical discharges between the clouds and the ground, but is produced in volcanic eruptions all throughout the world, and throughout history as well. After countless generations, where we wondered what could produce such an unusual but spectacular show, we’ve finally figured it out.
“3.) Different stars are visible from different latitudes. Look up at the night sky from a very high (northern) latitude location, and you’ll see the Big and Little Dippers, the bright orange giant Arcturus, and the Pleiades, among other sights. Yet if you head to the south pole, none of these celestial sights are visible, but you can see Alpha Centauri, the Magellanic Clouds, and the Southern Cross, all of which are never visible to most northern hemisphere skywatchers. If the Earth were flat, everyone on the night side of the Earth would see the same sky; this is another observation that the flat Earth can’t account for.”
There are lots of ways to demonstrate that the Earth is round. You can measure shadow differences at different latitudes and calculate its circumference, as Eratosthenes first did more than 2,000 years ago. You can circumnavigate the globe, measuring the distance you have to travel along your journey. Or you can simply fly “up” to space, and measure the curvature of the Earth directly. Yet even if you couldn’t do any of those, there are five simple observations that anyone can make that wouldn’t be the same if the Earth were flat instead of round. The night sky would look the same from everywhere on Earth, lunar eclipses would only ever occur at midnight, sunsets and sunrises would occur at the same time in New York as they did in Los Angeles, and much, much more.
Earth’s Rotation IS Slowing Down. But More Earthquakes? That’s A Hypothesis, Not A Fact
“However, there are many reasons to be skeptical. The connection between the changes in the magnetic field and Earth’s periodic slowing down appears to be correlative, but no causal link has been established. We are not certain that this mechanism is real. We’ve also only had approximately four years since 1900 that display this excess of earthquakes, and to predict that 2018 will be the fifth requires a rather large leap-of-faith. Finally, 2017 has only exhibited seven earthquakes of magnitude 7.0 or higher: well below the 15-20 average. Statistical fluctuations are large, and even if we get 25-30 earthquakes next year, that doesn’t necessarily mean that the Earth’s slowing rotation caused it.”
Predicting earthquakes has proven to be one of the most difficult scientific tasks humanity has ever taken on. Although the location — the where of earthquakes — has been relatively easy to predict on average, owing to our understanding of plate tectonics, the when of earthquakes has been thus far impossible. Since 1900, we’ve seen an average of around 15-20 earthquakes a year, but with large fluctuations. For example, even though powerful earthquakes have rocked numerous populated areas this year, there have only been 7, so far, of magnitude 7.0 or greater. Yet a bold prediction has just been made: that 2018 will see approximately 25-30 earthquakes of magnitude 7.0 or greater, owing to the slowing rotation of Earth from 2014-2018. It’s based on a long-term correlation we’ve observed, but the evidence is far from concrete.