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jaydnul
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Is it because the speed at which the asteroid is coming in greatly increases the friction between it and the air molecules in the atmosphere?
lundyjb said:Is it because the speed at which the asteroid is coming in greatly increases the friction between it and the air molecules in the atmosphere?
kevinferreira said:The shuttle was made to survive it (aerodynamics, materials, mechanics), the asteroid wasn't.
Certainly it will if the Thermal Protection System is compromised, as was the case with Columbia. If the TPS is intact, Shuttles return to Earth safely as they have done 128 times.SteamKing said:Who says that a space shuttle won't burn up on re-entry?
Look up the space shuttle Columbia, 2003.
lundyjb said:So does it have anything to do with speed and friction? If i were moving at 50 miles an hour from the tip top of the atmosphere to the ground, i wouldn't burn up, right?
lundyjb said:So does it have anything to do with speed and friction? If i were moving at 50 miles an hour from the tip top of the atmosphere to the ground, i wouldn't burn up, right?
Drakkith said:No, you would survive easily. An asteroid is moving at several miles per second on average I believe. The space shuttle re-entered at about around Mach 25, 8,200 m/s (30,000 km/h; 18,000 mph).
chill_factor said:but you can't stay at 50 mph. you need external power to resist acceleration downwards. even when you stop accelerating your potential doesn't stop dropping, that potential just gets turned to heat.
What's wrong with a regular-old rocket engine?StrayCatalyst said:...but unless you're using antigravity, a space elevator, or some similar, your mass will be gaining speed until it hits terminal velocity.
russ_watters said:What's wrong with a regular-old rocket engine?
Yes - speed and momentum/energy transfer, as well as friction, which is a shear force.lundyjb said:So does it have anything to do with speed and friction? If i were moving at 50 miles an hour from the tip top of the atmosphere to the ground, i wouldn't burn up, right?
NASA said:TIG-1 hour
Mission Control gives the "go" for deorbit burn.
DEORBIT BURN
The orbiter and crew are officially on their way home.
During reentry and landing, the orbiter is not powered by engines. Instead, it flies like a high-tech glider, relying first on its steering jets and then its aerosurfaces to control the airflow around it.
Landing-30 minutes
Roughly half an hour after the deorbit burn, the orbiter will begin to encounter the effects of the atmosphere. Called entry interface, this point usually takes place at an altitude of about 80 miles, and more than 5,000 statute miles from the landing site.
Early in reentry, the orbiter's orientation is controlled by the aft steering jets, part of the reaction control system. But during descent, the vehicle flies less like a spacecraft and more like an aircraft. Its aerosurfaces -- the wing flaps and rudder -- gradually become active as air pressure builds. As those surfaces become usable, the steering jets turn off automatically.
To use up excess energy, the orbiter performs a series of four steep banks, rolling over as much as 80 degrees to one side or the other, to slow down. The series of banks gives the shuttle's track toward landing an appearance similar to an elongated letter "S."
As the orbiter slices through the atmosphere faster than the speed of sound, the sonic boom -- really, two distinct claps less than a second apart -- can be heard across parts of Florida, depending on the flight path.
Drakkith said:Yes I realize that. But the question was if your speed remained at 50 mph. If you could remain at 50 mph, which really isn't that far fetched, you would not burn up. I'm sure a very lightweight probe or something could be rigged with the right gear to keep it at 50 mph during its fall.
dgh856 said:I'm not sure keeping something falling through the atmosphere at 50 MPH is as simple as you think. Even with a very lightweight probe, the amount of fuel you would need to keep it at 50 MPH with a rocket engine after de-orbiting it would be incredible, and add incredible weight. Other systems, like parachutes, wouldn't become effective until the atmosphere is significantly thick, before which the body would undergo catastrophic friction anyway.
The actual ΔV to slow a falling body, especially a lightweight one, to 50 MPH wouldn't be that extraordinary, but keeping it at 50 MPH for the hours it would take to pass through the atmosphere at that velocity would be impossible. You'd need literally tons of fuel or a parachute the size of a medium-sized state.
Drakkith said:Why are we even talking about how feasible it would be? I never claimed it would be easy, only that an object moving at 50 mph would not burn up. I'm sure we can all agree that the OP is simply trying to understand the way friction works during re-entry, not develop a way to fall at 50 mph through the atmosphere.
dgh856 said:Given that the OP's original question has been correctly answered several times already, I was simply replying to what you said out of interest. Wasn't trying to upset anyone.
An asteroid burns up in the atmosphere because of friction and compression caused by air particles. As the asteroid travels through the Earth's atmosphere, it collides with air molecules at high speeds. This creates immense heat that causes the asteroid to burn up.
A space shuttle has a protective heat shield that is designed to withstand the intense heat of reentry into Earth's atmosphere. This heat shield is made of materials that can withstand temperatures up to 3,000 degrees Fahrenheit, allowing the shuttle to safely make it through the atmosphere without burning up.
The size of an asteroid does not affect its ability to burn up in the atmosphere. It is the speed and angle at which the asteroid enters the atmosphere that determines whether it will burn up or not. Larger asteroids may take longer to completely burn up, but they will still disintegrate due to the intense heat and pressure.
Yes, it is possible for an asteroid to make it through the atmosphere without burning up. This usually occurs with smaller asteroids that are less than 10 meters in diameter. These asteroids are not large enough to generate enough heat to completely burn up in the atmosphere, so they may make it to the ground and create a small impact crater.
Astronauts do not experience the intense heat of reentry because their spacecraft is designed to withstand the heat and pressure of entering the atmosphere. The spacecraft's heat shield protects the astronauts from the extreme temperatures, allowing them to safely return to Earth. Additionally, the shuttle's velocity and angle of reentry are carefully controlled to minimize the effects of friction and heat.