- 2925 - SPACE - living there and the weather? The Space Station has been an orbiting lab with 20 years of continuous human presence. On Nov. 2, 2000, the first crew, Expedition 1, arrived at the ISS. NASA astronaut William Shepherd was the space station's first commander, paving the way for 20 years of humans living and working in low Earth orbit. Space weather is one of today’s explorations.
--------------------------- 2925 - SPACE - living there and the weather?
- Since that first historic mission in 2000, the orbiting space lab has been continuously occupied by humans. The space station is in low Earth orbit, meaning astronauts spend months in microgravity. However, weightlessness, or zero gravity, can have significant short-term and long-term effects on astronauts.
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- Astronauts notice big differences in their body’s muscles in terms of how much they atrophy in your legs and how the fluid shifts that occurs once you go into a micro-g or zero-gravity environment. The fluid in the body normally held down by gravity on Earth shifts up into an astronaut's upper torso, chest and head.
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- Everybody who goes into space feels really stuffed up. They have a massive head cold for a couple days, then eventually comes to some type of steady state. The body adapts to that environment and you feel better and then you can go about your daily chores."
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- In the microgravity environment of the space station, astronauts float around, so "up" and "down" mean different things than on Earth. Once your body does get used to microgravity, up is wherever your head is.
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- However, for the first couple days in orbit, you are feeling upside down all the time and having no appetite. It was not until her fourth day in space that you finally start to feel acclimated to the microgravity environment.
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- Astronauts also tend to experience changes to their taste buds, such that food tastes more bland, so spicier foods are preferred while in orbit. Another difficulty of living in space is the challenge of going to the bathroom in microgravity, which the astronauts compared to sitting on a vacuum cleaner.
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- NASA has been studying how living in microgravity affects astronauts in preparation for crewed missions to return to the moon and one day travel to Mars or beyond. Longer space missions are known to impact the human body in a variety of ways, including triggering changes to astronauts' brain structure and function, vision, heart muscle cells and the diversity of bacteria in the gut.
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- Living and working in microgravity for long periods of time can also cause a loss of bone and muscle mass. On a short-duration space shuttle flight, you can probably get away without doing some high impact resistant and resistive exercise, and come back to Earth and your bones are still OK. If you do that on a long-duration flight, you'll come back with 20% less bone mass. So we are militant about 2 to 2.5 hours of working out a day, vitamin D supplements and understanding shifts in vision.
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- Long-duration spaceflight can also be associated with feelings of isolation due to the extended separation from family and friends. Learning to deal with this as astronauts can be applied to current events on Earth, such as the shelter-in-place orders amid the COVID-19 pandemic.
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- Space is not a single thing. It as many unknowns and many new discoveries to be found. And we are trying in this new age of discovering space. The just below the space station, the edge of space has an ever-growing fleet of satellites in low-Earth orbit that are locked in a constant, precarious battle with friction.
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- These satellites orbit in a normally quiet region hundreds of miles above the surface, at the edge of Earth's atmosphere. Usually, the satellites only feel a gentle push due to the headwinds of the rarified air there, but extreme storms from the Sun can change Earth's atmosphere enough to pull a satellite farther off orbit in one day than they'd normally experience in a year. They can also affect the space station’s orbit.
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- These orbital deviations don't cause satellites to fall out of the sky, but they can disrupt their communication with Earth, shorten their life spans, and can even increase the chances of a terminal collision in space. And what about our GPS readings. I could miss my turn.
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- While researchers have long been aware of this effect, known as “orbital drag“, a new collection of research led by NASA scientists is finding that less intense, but longer-lasting storms surprisingly have bigger effects on satellites' orbits than the shorter, more severe events.
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- NASA scientists have carefully monitored space weather and tracked orbital drag for years, since low-Earth orbit satellites provide the backbone to Earth and weather observations and telecommunications systems.
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- The new research, which looked at rare extreme historic storms, will help satellite operators better understand satellite lifetimes and dynamics, making the near-Earth space environment safer when the next big superstorm hits.
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- Orbital drag is very important. This new result highlights the fact that even during less extreme space weather events, orbital drag of satellites is of greater impact than we anticipated. And it is becoming more and more of an issue, simply because we've got more and more and more spacecraft up there.
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- The “Solar Dynamics Observatory” caught a glimpse of a huge coronal mass ejection, leaving the Sun on July 23, 2012. If such a coronal mass ejection had hit Earth, it could have caused trillions of dollars in damage to telecommunications and infrastructure.
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- What Causes Orbital Drag? Our closest star, the Sun, provides the light to nurture life on Earth. But it also spews dangerous particles and radiation that can affect astronauts and technology in space. Scientists study the many affects from these outpourings, including what happens when such eruptions are extreme.
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- When it comes to the thousands of active satellites in space, however, one of the key concerns is indirect effects from particles and radiation, even from lesser storms.
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- High-energy particles and radiation from the Sun can heat Earth's atmosphere as they collide with common molecules, like nitrogen and oxygen. The heated air rises and causes the atmosphere to expand like a balloon.
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- If a storm is strong enough, it will cause the atmosphere to expand so much that it engulfs the orbits of low-Earth orbit satellites that would otherwise fly through areas with little to no atmosphere.
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- Increased atmosphere is like running in a headwind and it slows you down. This is what causes “drag”. For a satellite, this resistance causes it to slow and drop down in altitude. During an extreme magnetic storm event, a satellite could drop nearly a third of a mile in elevation in one day.
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- A third of a mile is as much as a satellite would typically lose in a year. Improved models are finding that the effects of orbital drag extend twice as high into space as previously expected. This work also found more extreme storms heat and cool the upper atmosphere faster than smaller storms.
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- Scientists are finding that the effects of weaker, but longer-lasting storms might be just as impactful, if not more, than extreme storm events.
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- Such superstorms from the Sun are rare, only one has occurred since the dawn of the space age, and it was only half as powerful as the 1921 event. However, in the same period there have been dozens of lesser magnetic storms from the Sun, not all of which have reached Earth. Many more are aimed in a different direction.
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- The researchers found that the strongest storms don't necessarily produce the most drag. The effects of a longer, less intense storm can build up over time, ultimately causing more orbital drag than a short, powerful storm.
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- Solar storms disproportionately affect low-Earth orbit satellites, which live within the first 375 miles of space above Earth's surface, which can be enveloped by a swelling atmosphere. The space station orbit is 200 miles up.
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- The vast majority of new satellites call this region home, including the quickly growing constellations of communications satellites launched by private industries. Once a satellite is knocked out of orbit, the effects only worsen, since at lower altitudes there is more atmosphere and thus more drag, even in calm conditions. The lower a satellite is dragged, the amount of drag it experiences only increases.
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- Orbital drag is bad for a satellite that wants to stay at a working altitude, but it's also bad for nearby satellites that might collide with a satellite that's been dragged off-course.
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- Even tiny pieces of space debris pose a huge risk for satellites, so minimizing collisions is key to keeping the near-Earth environment a functional space for satellites.
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- The new results are just one aspect of space weather and the field of “helophytic“, in which scientists try to understand how activity on the Sun ripples across the solar system and affects Earth.
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- Space weather is all about prediction - we need to predict it, we need to be safe.
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- Scientists at NASA have been monitoring the space weather and effects of drag on satellites for decades, particularly since the 1970s when solar activity led to increased drag on NASA's Skylab mission, causing it to deorbit earlier than expected.
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- Improved models over the years have helped scientists better understand the effects of normal solar activity on orbital drag. The rarity of extreme events has made it difficult to know exactly how they might affect current satellites.
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- In order to provide advance warning of coming storms, many of NASA's heliophysics missions help monitor the Sun's activity. Missions like the “Solar Dynamics Observatory” and the “Solar and Heliophysics Observatory’ keep a constant eye on the Sun, while other missions like the “Ionospheric Connection Explorer“, “Space Environment Testbeds‘, and the upcoming “Atmospheric Waves Experiment” study how space weather and solar variability affect Earth's upper atmosphere and satellites and other technology.
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- There is a lot to Google if you want to learn more. This new information helps keep NASA astronauts and assets in space safe during space weather events. No one can predict exactly when the next big solar superstorm or long-lasting storm will hit.
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- The Sun might be 93 million miles away, but that doesn't mean it doesn't have a huge impact on Earth. Living in space is no cake walk. Admire the men and women that are willing to go up there and learn about it. Experience is a tough teacher. Reading is a much safer education.
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- December 3, 2020 2925
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