At the same time, NASA announced the extension of the STS-130 Endeavor mission by a day to complete activities to install water purification systems that had to be abandoned during the current mission
Under the direction of Steve Robinson, Benken installed an insulating cover on part of the outer side of the component. He also prepared Tranquility for moving the observation deck to the cupola, and opened a shutter for the camera as well as installed systems that would secure the cupola in place.
Patrick at the same time installed an air valve to Traquility and attached eight rails to the outside of the component.
It was the second of three spacewalks planned for this mission and the 232nd performed by American astronauts. It was also the 139th mission in support of the construction and maintenance of the International Space Station. Meanwhile inside the station the crew completed the necessary procedures to activate Tranquility.
NASA also announced that the Endeavor mission has been extended by one day, and is now scheduled to land on Sunday, February 21, after leaving the station Friday night. The day that was added, the 11th in number will be used to transfer two water purification systems and cabinets for them, a garbage treatment facility and an oxygen production system into Tranquility. This activity was postponed from previous days of the mission due to the need to carry out repairs and quality checks.
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jewel:
What would happen to the satellite if the gravity all of a sudden disappeared. How would it affect his trajectory?
And another question, what would have happened to the satellite's orbit if its mass had increased a billion times while its speed did not change and the force of gravity remained the same.
Many thanks to Miki and especially to Adi for the detailed answers!
Mickey, you have an error in the calculations (actually you have two, but the second one is probably just a calculation error).
You took the height of the satellite (200 km) as the radius in your calculations, which of course is not correct. The radius of the earth is about 6300 km (approximately), so in your calculations you should have used about 6500 km, and then you would have accepted that the forces The real (gravitational) and the virtual (centrifugal) balance each other. It also makes sense, otherwise if what you wrote was true all the countries of the world would lose their satellites at a dizzying rate 🙂
And I'm bothered
Did they manage to get a building permit for the balcony?
Angular momentum of a body/system is maintained as long as no torques act on the body. Torque is the part of the force that affects angular momentum. I will explain:
Just as a body has linear momentum (the amount of movement in a straight line - it's simply mass times velocity), which is preserved, as long as no force is applied to the body (applying a force causes a change in velocity and momentum changes), so a torque changes the angular momentum (imagine a door on a hinge. When you press Perpendicular to the door far from the hinge, near the handle it turns easily. When you press the door close to the hinge, it hardly turns. When you press near the handle but on the narrow side of the door, meaning your finger is parallel to the door and you press in the direction of the hinges, it probably does not turn at all. In the first case you applied a large torque, in the second case you applied a small torque, and in the third case you applied no torque at all, even though in all three cases you pressed with the same force).
The case of a central force (gravitation) is a case in which the force acts in a radial direction (that is, on a line connecting the body and the center of force), as in the third case of the door, and therefore does not exert a torque on the body, and therefore angular momentum is conserved (it would be conserved even if it were not There were forces at all. This may seem strange to you, since if there are no forces at all the body will continue to move in a straight line and not rotate, that is true, but relative to a certain point the body does rotate - draw it for yourself and you will see that at every point on the trajectory the line connecting the body and the point forms an angle different, and therefore there is a momentary rotation around the point).
Sentence 2 is correct.
Sentence 3 is incorrect - the bodies move closer and further apart, they move in all kinds of trajectories. There are open orbits (an asteroid that comes from afar, passes by the sun, changes its orbit slightly and disappears into space again) and closed orbits, which are an ellipse and its special case - a circle. Most bodies move in ellipses, meaning they move closer and further apart. What I said is that conservation of angular momentum means that if a body started with some velocity in a direction not parallel to the direction of the center of force, then it will never crash into the center - there is a minimum radius less than which the body cannot approach - I explained why bodies do not crash into each other. If the speed of the body (kinetic energy) is small enough (we will not go into why it should be small now) then the orbit is closed as mentioned - an ellipse, therefore there is also a maximum distance that the body cannot move away from, this time it is because of gravity that pulls the body, therefore the body will move Between these two distances, it will zoom in and out and make an elliptical motion.
My father intrigued me with your question and I looked into the matter. To answer your question, you need to understand what the forces are that act on these bodies, sum them up vectorially, and from there conclude what the equal force and direction acting on those bodies are. Let's assume the following: it is a body (let's say debris from a satellite) with a mass of 100 kg, the holiday around the earth at a distance of 200 km (take a typical distance and speed for a satellite close to the earth: http://lib.cet.ac.il/pages/item.asp?item=7444), at a typical speed for such a satellite which is 8000 meters per second. There are 2 main forces moving on such a body, the gravitational force of the Earth and a centrifugal force that are opposite to each other in their directions. See the following explanations:
Gravity:
http://he.wikipedia.org/wiki/%D7%9B%D7%91%D7%99%D7%93%D7%94
Centrifugal force:
http://he.wikipedia.org/wiki/%D7%9B%D7%95%D7%97_%D7%A6%D7%A0%D7%98%D7%A8%D7%99%D7%A4%D7%95%D7%92%D7%9C%D7%99
After putting it in the two formulas we get: 1 kilo-newton in favor of gravity and on the other hand 32 kilo-newtons in favor of the centrifugal force. That is, from this result it is possible to conclude quite clearly that the same body moves away from the earth over time.
It should be noted that the assumption was that the body has no speed towards the earth or any other direction except for its tangential speed which creates the centrifugal force.
In conclusion, most of the chances indicate that these bodies will not be attracted to the Earth, but there are still many cases that they do, and even if they do, they burn up in the atmosphere and may look like meteors.
Hope I helped…
So actually gravity acts on the object and causes it to maintain its "angular momentum"..?
In your words "if the minimum radius of a piece of debris is smaller than the atmosphere" you mean that the orbit of the object is low, therefore it rubs against the atmosphere, slows down (burns) and falls, which does not happen on the moon..
So as long as there is no deceleration, say by the atmosphere, then the bodies are not expected to get closer?
It seems to me that the moon does get closer and farther away from time to time, is that true?
Father, you made a salad.
The forces that act between celestial bodies (and debris between them) are the force of attraction (gravitation). This is not about magnetism.
When a body moves under the influence of a force pulling towards the center (like gravity) there is conservation of angular momentum. Those who don't know what it is can see it as "the amount of rotational motion". Let's imagine for the moment that this is a point source of attraction (instead of the big earth there is a point that attracts with the same force. In terms of physical equations this simplification has no effect). Conservation of angular momentum inevitably entails that if the body started with some velocity that was not directed in the direction of the center of force (it has a tangential component) it will never fall on the center of force, because the amount of rotational motion must always be preserved, that is, the body always performs some kind of rotational movement around the center of force ( Whereas a state of falling is a state in which the body's velocity is directed directly to the center of force at the moment of the body's impact (otherwise it would not have hit)). The conservation of angular momentum therefore dictates that there is always a minimum distance that a body can approach the center of force (this distance can be easily found from the conservation of energy). In practice, the airspace is not a point, and it has an atmosphere that slows down the body if it enters it, therefore, if the minimum radius of a piece of debris is smaller than the atmosphere, it will fall on the airspace. On the other hand, for celestial bodies such as the Earth and the Moon, there is no problem because the radius of the Moon's orbit is much, much, much larger.
A question regarding the forces acting on "heavenly grams" large and small..
What prevents "space debris" such as "satellite debris" from being drawn back towards the Earth?
After all, the same "bone" was processed by any stabilizing factor or other factor that would keep it in orbit!
Is a combination of the "principle of persistence - inertia" as well as (relatively) low mass and weight the ones that cause the "objects" to stay in orbit and not continue (immediately) towards the Earth?
And the same question regarding much larger bodies (relatively) such as the moon and the globe and the earth, as well as the earth and the sun.
Are the same laws that keep the objects in their current location?
And if so, isn't the same force (magnetism?) that prevents a ball from moving away from the Earth strong enough to pull the Earth towards it?
I would be happy to receive an explanation on the matter.