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NASA Reveals How Mars Went from Habitable Planet to Barren Wasteland
NASA is getting really serious about its mission to land humans on Mars in the 2030s.
NASA's mission to send humans to Mars by the 2030s is looking especially ambitious given its findings about the Martian atmosphere — or rather the lack thereof. For over a year, the MAVEN spacecraft has been measuring Mars' atmosphere and now NASA is ready to share the results.
Solar wind traveling at 1 million miles per hour is carrying away the Martian atmosphere at a rate of 100 grams per second. That's one-quarter pound of oxygen and carbon dioxide that is leaving Mars' atmosphere every hour, never to return. At that rate, it would take a couple billion years for the atmosphere to dissipate completely, so NASA scientists believe most of Mars' atmosphere was stripped away at a much earlier stage in the solar system's life cycle — when the Sun was much more active.
Could the Sun strip the Earth of its atmosphere? Besides the slow rate at which Mars is losing what remains of its atmosphere, Earth has another advantage. Its magnetic field mostly protects us from severe atmospheric degradation.
Can understanding Mars help us to eventually create a new Martian atmosphere, allowing humans to live there more easily? Yes and no, say NASA scientists. The easiest theoretical way to terraform Mars would be to unlock stores of CO2 trapped beneath the planet's surface. Unfortunately, that CO2 just isn't there: It's been blown off into space by the Sun. Understanding Mars' atmosphere, however, is essential to carrying human life to the planet and helping a NASA crew survive — without the atmosphere that crucially protects life on Earth.
In the long term, we've got to find a way to establish a colony on Mars, says Stephen Petranek. The survival of the species depends on it.
Join multiple Tony and Emmy Award-winning actress Judith Light live on Big Think at 2 pm ET on Monday.
The team caught a glimpse of a process that takes 18,000,000,000,000,000,000,000 years.
- In Italy, a team of scientists is using a highly sophisticated detector to hunt for dark matter.
- The team observed an ultra-rare particle interaction that reveals the half-life of a xenon-124 atom to be 18 sextillion years.
- The half-life of a process is how long it takes for half of the radioactive nuclei present in a sample to decay.
What we know about black holes is both fascinating and scary.
- When it comes to black holes, science simultaneously knows so much and so little, which is why they are so fascinating. Focusing on what we do know, this group of astronomers, educators, and physicists share some of the most incredible facts about the powerful and mysterious objects.
- A black hole is so massive that light (and anything else it swallows) can't escape, says Bill Nye. You can't see a black hole, theoretical physicists Michio Kaku and Christophe Galfard explain, because it is too dark. What you can see, however, is the distortion of light around it caused by its extreme gravity.
- Explaining one unsettling concept from astrophysics called spaghettification, astronomer Michelle Thaller says that "If you got close to a black hole there would be tides over your body that small that would rip you apart into basically a strand of spaghetti that would fall down the black hole."
A new study looks at what would happen to human language on a long journey to other star systems.
- A new study proposes that language could change dramatically on long space voyages.
- Spacefaring people might lose the ability to understand the people of Earth.
- This scenario is of particular concern for potential "generation ships".