We'll Say Goodbye To Our Planet In 1,000 Years, Says Stephen Hawking
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Humans have been on Earth for hundreds of thousands of years. So far so good, right? Well, according to famed physicist Stephen Hawking, things around here are about to get ugly for us. It's time to start poking around the neighborhood for a better place to call home. And by place, we mean planet.
Rogue Planets Wander The Galaxy Without A Star To Call Home
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Billions of stars orbit the center of our galaxy, and many of these stars have at least one planet orbiting them. But not all stars belong to a galaxy, and not all planets orbit a star. Rogue planets are worlds that drift untethered to any star, and experts estimate that there are billions of them in our galaxy alone.
The Trailblazing Scientific Career Of Maria Zuber
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"In planetary science, you can ask really big questions," said Maria Zuber, Vice President of Research at MIT, in an interview with Smithsonian Magazine. Maria has been tackling big questions her entire career. She was the first woman to run a NASA spacecraft mission, the first woman to lead a science department at MIT, and one of the first two women to receive NASA's Distinguished Public Service Medal. Her passion is planetary science, which includes the study of planets, moons, and planetary systems.
Earth May Have Entered A New Epoch
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We may be in a new epoch. Like the humans that survived the last glacial period to move from the Pleistocene to the Holocene, modern humans may have left the Holocene to enter the brand-new Anthropocene—the "age of humans." To delineate these stretches of time, geologists must identify individual boundaries in layers of rock known as strata. If a boundary is found in rock all over the world, the International Commission on Stratigraphy (ICS) appraises it for entry in the International Chronostratigraphic Chart, which defines geologic time in terms of eons, eras, periods, epochs, and ages. Often, these rock boundaries are caused by natural events such as ice ages and volcanic activity. The Anthropocene is not yet an official epoch, but if it becomes one, it will be defined by human activity—specifically, the significant changes we've made to the land, air, and water. The date of the epoch's start is up in the air, but it will most likely be 1945, the date of the first nuclear bomb detonation. There's another thing that's unusual about the Anthropocene beyond its human influence: geologic time is usually captured in rock, and it's too early to see human influence in the geologic record. If the ICS adds this epoch, it will be the first of its kind. Explore the science of strata with the videos below.
70% Of Earth's Fresh Water Is Frozen
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About 71% of the Earth is covered in water. Most of that is in oceans, rivers, and lakes, but some is frozen in the Earth's two ice sheets. Those ice sheets, which cover most of Greenland and Antarctica, only contain 2% of the world's total water supply, but a whopping 70% of the Earth's fresh water. Scientists estimate that if the Antarctic Ice Sheet—the larger of the two—melted, sea level would rise by around 60 meters (200 feet). Not only that, but it could affect the weather: a study showed that less sea ice in the Arctic causes rainier summers in western Europe, and another study suggests that it's causing more extreme heat waves in the United States and elsewhere. And counterintuitively, melting ice also causes more melting ice. A 2016 study found that a shrinking in the Greenland Ice Sheet causes what are known as "blocking events," where high-pressure systems park themselves on top of one area for days or even weeks. This brings warm, moist air that heats the surface below and causes even more ice to melt. Explore the relationship between polar ice and climate change in the videos below.