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How can the International Space Station orbit without burning up? – Mateo, 8 years old, New York, New York

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Thousands of satellites and two operational space stations fly through Earth's orbit, including the International Space Station, which weighs as much as 77 elephants. The International Space Stationor ISS, is home to scientists and researchers from around the globe who contribute to discoveries in medicine, microbiology, earth and space science, and more.

One of my first jobs in aerospace engineering was working on the ISS, and the ISS stays considered one of my favorite aerospace systems. I now work at Georgia Tech, where I teach aerospace engineering.

The ISS orbits the Earth in a short time at 5 miles per second (8 kilometers per second), meaning it could fly from Atlanta to London in 14 minutes. But at the identical time, small pieces of rock called meteoroids shoot through space and burn up once they hit the Earth's atmosphere. How is it that some objects – corresponding to the International Space Station – orbit the Earth unscathed, while others, corresponding to asteroids, burn up?

To answer why the ISS can remain in orbit unscathed for many years, you first need to know why some things, like meteoroids, actually burn up once they enter our planet's atmosphere.

Why do meteoroids burn up within the atmosphere?

Meteoroids are small pieces of rock and metal that orbit the sun. These space rocks can travel at speeds between 7 and 25 miles per second (12 to 40 km per second). That's fast enough to cross your entire United States in about 5 minutes.

Sometimes a meteoroid's orbit overlaps with Earth's and the meteoroid enters Earth's atmosphere – where it burns up and disintegrates.

Even though you possibly can't see them, the atmosphere is filled with particles, mostly nitrogen and oxygen, that make up the air you breathe. The further you’re from the Earth's surface, the lower the density of particles within the atmosphere.

The The atmosphere consists of several layers. When something enters Earth's atmosphere from space, it must go through each of those layers before reaching the bottom.

Meteoroids burn up partially of the Earth's atmosphere called mesospherewhich is 48 to 80 kilometers above the bottom. Even though the air up there may be thin, meteoroids still encounter air particles as they fly through.

When meteoroids hurtle through the atmosphere at very high speeds, they’re destroyed by a process that causes them to heat up and break apart. The meteoroid pushes the air particles together, just like how a bulldozer pushes earth. This process creates a whole lot of pressure and warmth. The air particles hit the meteorite at hypersonic speed – much faster than the speed of sound – causing atoms to interrupt away and form cracks within the meteoroid.

The high pressure and hot air penetrate into the cracks, cause the meteorite to interrupt apart and burns because it falls through the sky. This process known as Meteoroid ablation and is what you really see while you witness a “shooting star.”

Why doesn't the ISS burn?

So why isn't this happening with the International Space Station?

The ISS doesn’t fly within the mesosphere. Instead, the ISS flies in the next and significantly less dense layer of the atmosphere called the thermospherewhich extends from 50 miles (80 km) to 440 miles (708 km) above Earth.

The Kámán Lineconsidered the frontier of space, lies within the thermosphere, 62 miles (100 kilometers) above the Earth's surface. The space station flies even higher, about 250 miles (402 km) above the surface.

The thermosphere incorporates too few particles to transfer heat. At the peak of the space station, the atmosphere is so thin that you just would wish a box the scale of Lake Superior to gather enough particles comparable to the mass of an apple!

As a result, the ISS doesn’t experience the identical interactions with atmospheric particles, nor the high pressure and warmth that meteoroids flying closer to Earth experience, so it doesn’t burn up.

A top-class research center

Although the ISS doesn’t burn up, there are large temperature fluctuations. As it orbits the Earth, it’s exposed to alternating periods of direct sunlight and darkness. Temperatures can reach 250 degrees Fahrenheit (121 degrees Celsius) when exposed to the sun, after which they’ll drop as little as -250 degrees Fahrenheit (-156 degrees Celsius) when it’s dark – a variation of 500 degrees Fahrenheit (277 degrees C) because it moves through orbit.

The engineers who designed the station fastidiously chosen materials that might withstand these temperature fluctuations. The interior of the space station is kept at comfortable temperatures for the astronauts, just as people on Earth heat and funky our homes to remain comfortable inside.

Research on the ISS has led to progress as improved Water filtration technologiesa greater understanding of the earth Water and energy cycles, Techniques for Growing Food in Space, Insights into black holesa greater understanding of how the human body changes during prolonged space travel and latest studies on quite a lot of diseases and coverings.

NASA plans to maintain the ISS lively until 2030, when all astronauts return to Earth and the ISS will accomplish that deorbitedor be deorbited by a specially designed spacecraft.

As it sinks through Earth's atmosphere throughout the deorbiting process, it enters the mesosphere, where many parts of it heat up and decay.

Some spacecraft, corresponding to the crew capsules that carry astronauts to and from the ISS, can survive re-entry into the atmosphere Heat shield. This is a special layer fabricated from materials that may withstand very high temperatures. The ISS just isn’t designed for this and subsequently doesn’t have a heat shield.

If you need to see the space station because it flies over your area, you possibly can accomplish that Check out NASA's website to search out out when it could be visible in your area.

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SpaceX's upcoming Polaris Dawn mission must be historical in additional ways than one. Polaris Dawn won’t only orbit the Earth higher than any astronaut in over 50 years, but may also enable the primary private spacewalk.

The launch of the mission was originally planned for August 27, but there have been delays – first for a helium leak after which for bad weather. SpaceX representatives have said They observe the weather to postpone the beginning.

The crew consists of 4 people: mission commander Jared Isaacman, Scott Poteet, a 20-year Air Force veteran, and SpaceX employees Anna Menon and Sarah Gillis. The launch took place on a Falcon 9 rockettravel in a SpaceX Dragon capsule called resilience.

As Space policy expertI consider this mission to be a crucial step in the event of economic spaceflight. If successful, this mission will show that personal firms are working to develop the capabilities needed to fly to the Moon or Mars.

Commercial space travel

Polaris Dawn will spend its time in space testing communications between it and Earth. Starlink satellites and accomplished nearly 40 experiments. Many of those experiments will study how the human body reacts in low gravity environments and measure the radiation to which the capsule is exposed.

Polaris Dawn's biggest task, nevertheless, will likely be its first private spacewalk. Spacewalk will Test SpaceX's latest extravehicular activity suits and find out how they function within the gravitational environment of space.

Polaris Dawn will not be the primary industrial space mission that SpaceX has launched. In addition to providing Launch services for NASASpaceX also sells flights on its Falcon 9 rocket and Dragon crew capsule to individuals and corporations.

SpaceX's first industrial mission, Inspiration4, launched in 2021 and was led by Isaacman, the commander of Polaris Dawn.

After that mission, Isaacman purchased three more flights from SpaceX and worked with the corporate to launch the Polaris program. Although neither Isaacman nor SpaceX have published exact figuresSeats on the Dragon have already sold for around 55 million US dollars.

Polaris Dawn is simply the primary of three planned Polaris missions. While few details have been released concerning the second, The third mission will likely be the primary launch of the SpaceX spacecraft with humans on board.

High orbit

Given SpaceX’s ambitions To conduct its own missions to the Moon and Mars, the corporate must develop and test the numerous elements required for such missions. It must design and test space suits, conduct longer missions that mimic travel time to places just like the Moon, and show the flexibility to speak with Earth.

Polaris Dawn's high-flying orbit will take people further from Earth than within the last 50 years.

At its peak, Polaris Dawn plans to orbit greater than 850 miles (1367 kilometers) from Earth. That is greater than twice the gap between Earth and the International Space Station, which is positioned at an altitude of 408 km across the. It may also be the best orbit humans have ever reached for the reason that Apollo program sent astronauts around and to the moon.

Testing latest suits

Perhaps more importantly, the spacewalk will latest EVA suitsDeveloping these suits is maybe one of the crucial difficult tasks ever.

NASA learned early on that Spacesuits are incredibly trickyThey must provide life support and protection from the space environment while allowing astronauts freedom of movement. This is especially difficult because pressure suits are bulky and difficult to maneuver around in, resulting in exhaustion.

NASA developed its current generation of EVA suits within the Eighties. This summer alone, NASA has cancelled several spacewalks attributable to Suit Discomfort And Coolant leaks.

The Polaris Dawn crew is predicted to conduct their extravehicular activities on August 30. They will lower their orbit to about 434 miles (700 km) to scale back the crew Radiation exposure.

All 4 crew members of the Polaris Dawn will prepare for the spacewalk. After all the capsule is depressurized, two crew members – Isaacman and Gillis – will leave the relative safety of the Dragon capsule to spend about two hours in space.

A charitable cause

Polaris and Polaris Dawn aim to boost money for childhood cancer research while expanding SpaceX’s space exploration capabilities. As a tech billionaire, Isaacman has a long story of charitable donations.

Like Isaacman’s earlier Mission of Inspiration4Polaris Dawn is also collecting donations for St. Jude Children's Research Hospital, in a single case asking for donations in return for Doritos chips specially developed for space.

Isaacman's commitment to combining this mission along with his philanthropy suggests that he understands the criticisms many individuals have of the so-called billionaire space club. These arguments often include the concept that billionaires like Elon Musk and Jeff Bezos would help people more in the event that they spent their money on things like poverty alleviation reasonably than on space missions.

While private missions like this should not financed with taxpayers' money and doesn’t require public support. Isaacman's decision to make St. Jude a partner creates tangible and immediate advantages on Earth.

Like a lot of SpaceX's activities, Polaris Dawn is ambitious but needed for the corporate's future plans. Before SpaceX can fly to Mars, it must first take a walk – or more accurately, a spacewalk.

SpaceX's upcoming Polaris Dawn mission needs to be historical in additional ways than one. Polaris Dawn won’t only orbit the Earth higher than any astronaut in over 50 years, but can even enable the primary private spacewalk.

The launch is scheduled for August 27, 2024. The crew consists of 4 people: mission commander Jared Isaacman, Scott Poteet, a 20-year-old Air Force pilot, and SpaceX employees Anna Menon and Sarah Gillis. The launch will happen on a Falcon 9 rockettravel in a SpaceX Dragon capsule called resilience.

As Space policy expertI consider this mission to be a crucial step in the event of economic spaceflight. If successful, this mission will reveal that non-public corporations are working to develop the capabilities needed to fly to the Moon or Mars.

Commercial space travel

Polaris Dawn will spend its time in space testing communications between it and Earth. Starlink satellites and accomplished nearly 40 experiments. Many of those experiments will study how the human body reacts in low gravity environments and measure the radiation to which the capsule is exposed.

Polaris Dawn's biggest task, nevertheless, shall be its first private spacewalk. Spacewalk will Test SpaceX's latest extravehicular activity suits and find out how they function within the gravitational environment of space.

Polaris Dawn will not be the primary industrial space mission that SpaceX has launched. In addition to providing Launch services for NASASpaceX also sells flights on its Falcon 9 rocket and Dragon crew capsule to individuals and firms.

SpaceX's first industrial mission, Inspiration4, launched in 2021 and was led by Isaacman, the commander of Polaris Dawn.

After that mission, Isaacman purchased three more flights from SpaceX and worked with the corporate to launch the Polaris program. Although neither Isaacman nor SpaceX have published exact figuresSeats on the Dragon have already sold for around 55 million US dollars.

Polaris Dawn is barely the primary of three planned Polaris missions. While few details have been released in regards to the second, The third mission shall be the primary launch of the SpaceX spacecraft with humans on board.

High orbit

Given SpaceX’s ambitions To conduct its own missions to the Moon and Mars, the corporate must develop and test the numerous elements required for such missions. It must design and test space suits, conduct longer missions that mimic travel time to places just like the Moon, and reveal the flexibility to speak with Earth.

Polaris Dawn's high-flying orbit will take people further from Earth than within the last 50 years.

At its peak, Polaris Dawn plans to orbit greater than 850 miles (1367 kilometers) from Earth. That is greater than twice the gap between Earth and the International Space Station, which is positioned at an altitude of 408 km across the. It can even be the very best orbit humans have ever reached for the reason that Apollo program sent astronauts across the moon and to the moon.

Testing latest suits

Perhaps more importantly, the spacewalk will latest EVA suitsDeveloping these suits is probably one of the difficult tasks ever.

NASA learned early on that Spacesuits are incredibly trickyThey must provide life support and protection from the space environment while allowing astronauts freedom of movement. This is especially difficult because pressure suits are bulky and difficult to maneuver around in, resulting in exhaustion.

NASA developed its current generation of EVA suits within the Eighties. This summer alone, NASA has cancelled several spacewalks as a consequence of Suit Discomfort And Coolant leaks.

The Polaris Dawn crew is anticipated to conduct their extravehicular activities on August 30. They will lower their orbit to about 434 miles (700 km) to scale back the crew Radiation exposure.

All 4 crew members of the Polaris Dawn will prepare for the spacewalk. After your complete capsule is depressurized, two crew members – Isaacman and Gillis – will leave the relative safety of the Dragon capsule to spend about two hours in space.

A charitable cause

Polaris and Polaris Dawn aim to boost money for childhood cancer research while expanding SpaceX’s space exploration capabilities. As a tech billionaire, Isaacman has a long story of charitable donations.

Like Isaacman’s earlier Mission of Inspiration4Polaris Dawn is also collecting donations for St. Jude Children's Research Hospital, in a single case asking for donations in return for Doritos chips specially developed for space.

Isaacman's commitment to combining this mission along with his philanthropy suggests that he understands the criticisms many individuals have of the so-called billionaire space club. These arguments often include the concept that billionaires like Elon Musk and Jeff Bezos would help people more in the event that they spent their money on things like poverty alleviation reasonably than on space missions.

While private missions like this should not financed with taxpayers' money and doesn’t require public support. Isaacman's decision to make St. Jude a partner creates tangible and immediate advantages on Earth.

Like lots of SpaceX's activities, Polaris Dawn is ambitious but needed for the corporate's future plans. Before SpaceX can fly to Mars, it must first take a walk – or more accurately, a spacewalk.

Most space mission systems so far have used a spacecraft designed to perform a whole mission by itself. Whether it was a weather satellite or a human-manned module like Apollo, almost every spacecraft has been deployed and carried out its one-time mission entirely by itself.

But today space corporations are exploring missions during which many satellites work together. For example, SpaceX Starlink constellations Thousands of satellites are being launched into space, and recent spacecraft may soon have the option to attach or interact with other satellites in orbit to repair or refuel them.

Some of those spacecraft are already in operation and serving customers equivalent to Northrop Grumman’s Mission Extension VehicleThis spacecraft has extends the lifespan of several communications satellites.

These recent design options and orbital capabilities make space missions seem more like large logistics operations on Earth.

We are researchers who’ve studied the space industry We have examined how the space sector could learn lessons from corporations like Amazon or FedEx to managing complex fleets and coordinating processes.

Lessons from the bottom transportation network

Space mission planners plan their routes to efficiently deliver their payloads to the Moon or Mars or into orbit, making an allowance for costs, timelines and capacities. But once they need to coordinate the collaboration of multiple spacecraft, route planning can develop into complicated.

Local logistics corporations solve similar problems daily, transporting goods and commodities across the globe, so researchers can study how these corporations manage their logistics to assist space corporations and agencies work out easy methods to plan their missions successfully.

A study funded by NASA In the early 2000s, he had an idea for simulating space logistics operations. These researchers considered orbits or planets as cities and the trajectories connecting them as routes. They also considered the payload, consumables, fuel and other items to be transported as goods.

This approach allowed them to reframe the issue of space missions as an issue of products flow – a difficulty that ground logistics corporations are continuously grappling with.

Lessons from ground logistics infrastructure

New Opportunities to refuel and repair of spacecraft in orbit create recent opportunities and challenges.

Space operators typically don't know which satellite will fail next, or when that can occur. For these recent technologies to be useful, space mission developers would wish to develop an infrastructure system. This could seem like a fleet of service vehicles and depots in space that may respond quickly to unexpected events.

Fortunately, space mission planners can learn from what happens on the bottom. City planners and emergency response organizations consider these sorts of challenges when deciding where to locate hospitals or fire departments. They also consider the capability of those facilities to answer unpredictable emergency calls.

We can draw an analogy between the design of a ground logistics system and the design of an area servicing system. In this fashion, researchers can use theories developed for ground logistics to enhance the design practice for space missions.

A study The study, published in November 2020, developed a framework for servicing spacecraft in orbit using what logistics experts call spatial queuing theory. Researchers most frequently use this modeling theory to research the performance of a ground logistics system.

Lessons from soil storage management

In the past, individual spacecraft conducted their missions independently, so if one satellite failed, mission engineers needed to design and send a substitute.

For missions with multiple satellites, equivalent to the Iridium satellite constellationOperators often Keep a number of spare parts in orbit.

This gets complicated for constellations with a whole lot or 1000’s of spacecraft. Mission planners wish to be sure they’ve enough spare satellites in orbit in order that if one satellite breaks they don't need to interrupt the mission. But sending too many spare satellites gets expensive.

In such large-scale setups, mission planners can learn from the methods Amazon and other ground corporations use to administer their warehouses. Amazon sets up these warehouses in specific locations and stocks them with specific items to make sure efficient delivery.

On-site inventory management theories may also help aerospace corporations overcome these challenges.

A study The study, published in November 2019, developed an approach that space corporations could use to administer their spare satellite strategies. This approach may also help them determine where in orbit to deploy their spare satellites to fulfill their needs while minimizing any service disruptions.

International dimensions

Spacecraft operate in a posh and rapidly changing environment. Operators have to know where other missions are operating and what rules they have to follow when refueling or making repairs in space. But in space, nobody has yet defined those rules.

Ships, aircraft and ground vehicles all have clear Road traffic rules to follow when interacting with other vehicles. For example, civilian ships and aircraft must share their location with other vehicles and officials to control traffic.

Some researchers are studying what similar rules might seem like for space. A study examined how developing rules based on a spacecraft's size, age, or other characteristics could help future space operations run more easily. For example, one rule could be that probably the most recently launched spacecraft should take responsibility for maneuvering when one other craft is in its path.

With more satellites and spacecraft being launched today than ever before, corporations and government agencies need recent technologies and policies to coordinate them. As space activities develop into more complex, researchers can proceed to use what they've learned on the bottom to recent space missions.