Did You Know That Ancient Mars Had Glaciers?
Did you know that ancient Mars had glaciers? While some people might find this hard to believe, it’s true! Scientists have found glacial deposits as old as four billion years on the planet Mars. However, these glaciers were not like those found on Earth today.
On Earth, polar ice caps hold as much as 75% of all fresh water
On Earth, the water on our planet is split between the vast oceans and other bodies of water. However, if you know where to look you'll find that there are more lakes on land than in any one place on Earth's oceans. Estimates say that about 1/4 of all fresh water can be found within lakes. Lake Baikal in Siberia is the largest lake by volume on Earth and holds roughly 23% of all freshwater on our planet! Nearby Lake Titicaca in Peru also contains an estimated 8% of total global freshwater and holds almost 7 times as much water as Los Angeles County, CA with an area that's over 31 times smaller. And, scientists estimate these two lakes combined could fill 80% of California's footprint! But what does this have to do with ancient Mars? Well, it turns out that ancient Mars had glaciers! Scientists believe that at one point the Martian climate was similar to Earth's. In fact, many of the valleys and channels we see today were likely carved out by glaciers during this time. The Red Planet may not have been a habitable world back then because of its low atmospheric pressure and lack of a thick ozone layer, but it would have been cold enough for some form of ice sheet or glacier to form. It just so happens that a few million years ago something happened on Mars and caused a drastic change in its atmosphere. Whether this was due to changes in volcanic activity, asteroid impacts, or whatever else we're still unsure of, but the end result was temperatures rose too high for any kind of permanent glaciation to happen again. Today, Mars has large deposits of carbon dioxide ice in its polar regions, but nothing like Earth's great glaciers! The last major glacial period here lasted from 25,000 - 15,000 years ago when ice sheets up to 3 miles thick formed around the globe. By comparison, Antarctica's Vostok Glacier alone is 6 miles deep! These periods of intense glaciation have punctuated the history of our planet throughout time and interestingly coincide with various extinction events. Just how quickly did they form? Over 10,000 years in less than 100 years! When climates warmed, they would retreat back into their icy homes until another cooling trend came along. We think that earlier lifeforms evolved to take advantage of these periods when natural resources were more abundant. And while it's difficult to tell whether these glaciers led directly to mass extinctions on Earth, they certainly seemed to coincide with them quite often and helped shape life as we know it today.
The other 10% of fresh water lies in glaciers covering Antarctica and Greenland
Earth's surface is 71% water and we need it to sustain our planet. But there are only 2% of fresh water on the planet. Six out of those seven percent is in glaciers that cover Antarctica and Greenland, according to National Geographic. Some scientists say this poses a significant problem if we rely too heavily on Earth's resources, while others claim it is not an issue as water will recede from the ice sheet to Earth eventually. One thing for sure is that climate change can drastically alter the amount of available freshwater, so we must find ways to conserve what little we have left. Experts also say that melting glaciers could lead to rising sea levels, which would make some areas uninhabitable. What other natural disasters are caused by global warming? According to the World Health Organization, experts predict more heat waves, more intense storms, worsening floods and droughts, worsening wildfires. More than 400 cities may be underwater by 2100 due to changes in the ice sheets, according to a recent study by Climate Central. The study found that at least 180 cities worldwide - including Miami and New Orleans - face high or very high risk of flooding due to meltwater from Antarctic ice sheets flowing into the ocean or directly onto land. Another report by NASA warns that most major coastal cities worldwide are at risk because of potential sea level rise due to global warming. Climate change impacts all people across communities around the world because no one is immune when extreme weather conditions occur; storms become stronger with warmer oceans, for example. What steps should we take now to protect our future generations? We can start by changing how we live day-to-day: driving less, recycling more, choosing sustainable food options. By making small changes in your lifestyle today you can help ensure that there will be clean air, fresh water and food for future generations. With drastic effects on the environment happening every day, we need to act now. Global warming is happening faster than scientists originally predicted; studies show that 97% of scientists agree that human activity has been largely responsible for climate change over the past century. If humans don't do anything about these devastating environmental effects then life as we know it could cease to exist in just a few decades. To stop these negative consequences from happening here are some things you can do: 1) Recycle whenever possible! Making everyday items like paper cups recyclable has helped keep plastic bottles off landfills and out of waterways where they contribute towards pollution (PDF). 2) Support green companies who care about both profit and sustainability! 3) Reduce water use by installing a low flow shower head and taking shorter showers. 4) Switch to renewable energy sources, like solar panels, that won't emit greenhouse gases. 5) Reducing meat consumption can help reduce methane emissions from livestock. 6) Save water by letting it flow before turning on the faucet and composting kitchen scraps to decrease the need for more bottled water. 7) Use fewer products that come in single-use packages. 8) Choose a diet that includes vegetables, fruits, and grains to consume more plant-based foods. 9) Avoid using straws and reusable water bottles, as these single-use plastics contribute to our country's landfills. 10) Participate in the March for Science on April 22nd 2017 to support evidence-based policy and research on climate change, the environment, and public health! The event is about bringing awareness to climate change and science. What will you do on Earth Day?
These kinds of polar ice caps are called paleo-ice caps
The southern polar ice cap of Mars is larger than the northern one. Similar to Earth, this ice cap has long-term shrinking and thickening trends. These are believed to be driven by changes in the sun's distance and changes in the tilt of the planet's rotational axis. The ice caps on Mars currently cover at least 70% of its pole, making it a distinctive icy world with a diameter close to that of Greenland! This helps scientists understand how glaciers may have formed on ancient, wetter, warmer Martian climate during earlier periods in the planet's history. For example, these kinds of paleo-ice caps likely existed in early Mars' time, when there was liquid water flowing over the surface. If so, this would indicate that early Mars had an environment friendly for life! It also suggests that some form of warming might have taken place on Mars which could explain why liquid water disappeared from the surface around 3 billion years ago. However, scientists believe that both sides of the poles were once covered in glaciers as recently as 200 million years ago. These glaciers would have been much smaller in size compared to today’s glaciers, but they still left their mark on the landscape. Scientists now think that most of the ice melted away due to volcanic activity or seasonal heat variations within the planet’s atmosphere. They've also determined that the present-day ice caps on Mars didn't come into existence until about 800,000 years ago. Interestingly enough, these new Martian ice caps are significantly younger than those of other planets in our solar system such as Saturn (2.5 billion years old) and Jupiter (1.6 billion years old).
This makes them potentially interesting places to search for signs of past habitability. By studying the deposits found under the ice sheets on Mars scientists can determine what types of materials were deposited before each freeze cycle began - including whether this region ever had liquid water at any point in its history! In order to do this, however, it is important for scientists to study geological features like channels and outflow valleys on Mars. Studies of these formations led researchers to conclude that Mars experienced a prolonged period of heavy rainfall more than 3 billion years ago. So far though, they haven't found evidence suggesting large amounts of liquid water at the current time! That being said, we know that liquid water flowed on ancient Mars, but slowly. There is a lot of research underway about where exactly this water went and if it had anything to do with the evolution of life on Mars. If scientists find conclusive evidence of liquid water on Mars, then it will be a huge discovery. Life needs the right ingredients to survive: oxygen, food, liquid water, and energy. On Mars, the first three requirements exist. What happens next depends on your interpretation of the age of Mars and its prospects for future habitability. Some scientists have estimated that Mars is too cold and its thin atmosphere doesn't allow for enough liquid water to exist on the planet's surface. Some scientists, on the other hand, say that Mars is similar to Earth in terms of the amount of liquid water it has had in its history. This means that water may have remained at Mars's surface even after billions of years ago. Evidence for this comes from the observation of gullies on slopes of glaciers as well as boulders scattered across these slopes. Both observations suggest that liquid water has seeped down slope and produced erosion along the way.
This hypothesis leads us to a question that many people ask themselves: Could humans live on Mars? While it sounds like science fiction, it's actually not impossible!
Was there ever a paleo-ice cap on Mars?
Mars is a cold, inhospitable place. Temperatures are very low, and ice cannot exist at the surface. However, there are many features on the Martian surface that look like they would be consistent with glaciers. There were two hypotheses proposed as to how this could happen: it could be seeping ice water or glaciers! The discovery of glacial-like flows in Hale Crater, pictured above, answered this question definitively – some of these areas were once covered by glaciers! It’s been estimated that such glaciers existed on Mars more than 3 billion years ago. These flowing icy masses may have slowed down erosion processes and helped deposit sediments over time. Scientists estimate that around 0.1% of the area of ancient Mars was once covered by glaciers; a similar amount as present day Antarctica! As mentioned before, when we think about Earth’s glaciers, we often envision them melting and retreating due to climate change. But what if you found out that ancient Mars had them too? Imagine trying to figure out why this happened. What caused their disappearance? One hypothesis is that after an asteroid impact on the planet, billions of years ago, climates changed rapidly enough for the glaciers to disappear into oblivion. Others say that it was just a natural event in Earth’s history - nothing unique about our Solar System! One thing remains clear - there are still many questions left unanswered about the past environment of Mars. What else do you wonder about Mars? Leave your comments below! Did you know that not only did ancient Mars have glaciers, but other celestial bodies might also have had glaciers? Pluto has made headlines recently because images from NASA's New Horizons mission showed mountains apparently coated in ice. With both of these discoveries scientists have gained new information about the environments where life might potentially exist elsewhere in our solar system. So stay tuned for future updates on space exploration! In the meantime, you can find me here on my couch watching Netflix. I'm always looking for new documentaries to watch so let me know if you have any recommendations. I love sci-fi and astronomy stuff! But sometimes science fiction can be really weird and doesn't match up with what we actually know. For example, take the idea of alien intelligence... If aliens exist then they must live somewhere right? Wouldn't aliens need something called water to survive?! Well, it turns out that planets in habitable zones usually have abundant amounts of water. And even better news is that astronomers now believe there are habitable planets out there orbiting stars within 100 light years from Earth! Hooray for intelligent life being closer than we thought!!
Scientists Find New Evidence That Ancient Mars Once Had a Paleo-Ice Cap
Every so often, some new research is released on ancient Mars that seems to suggest the Red Planet was once habitable. Researchers have long-known that glaciers flowed in a geologically recent past, and now there's new evidence that, yes indeed, glaciers have left their mark on the planet at some point. The discovery took place when scientists studied an impact crater of a meteor on the surface of the planet and found something quite unusual-a swath of ice older than any other ice that has been seen before. Analysis showed there were about 250 meters of ice below just one section of this crater - suggesting there's more ice still preserved in these regions since it can't all be seen from space. These findings show that the water is likely only frozen beneath the surface, not mixed into its soil like we see with Earth's permafrost. It tells us two things, says Patrick McGovern, who led the team of researchers. One: There had to be liquid water somewhere in Mars' history near this site. And two: It had to go underground or maybe evaporate because if it remained at or near the surface then we would see evidence for it. Either way, it means Mars must have gone through cycles of freezing and thawing over time. This deposit is probably a relic of an ice sheet that grew as snow piled up over many years, he said. A few individual snowfalls could never accumulate enough snow to form an ice sheet. The magnitude of the ice layer indicates that it may have formed over several thousand years, according to McGovern.E rosion created channels which allowed melted ice to flow down slopes and across the terrain. All this evidence combined points to a glacial period on ancient Mars; but how do they know that there weren't periods of glaciation before this one? They don't really know yet, but I think it's fascinating that we are able to piece together clues about our neighboring planet like this!
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