ROCKET SCIENCE explained in 15 minutes! And How do satellites work?
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Rocket Science and orbital mechanics of Satellites.
There are about 3000 operational satellites, owned by over 100 different countries orbiting the earth right now. About 550 of these are in geo stationary orbits - the satellite appears stationary compared to the rotation of the earth. Communications satellites are typically in such orbits. These allow you to leave your satellite dish in one position, and never have to change it.
Orbital mechanics is rooted in Keppler’s laws of planetary motion & Newton’s laws of universal gravitation.
These laws allow us to calculate the period and speed of such a satellite.
Speed = S = sq root(mu/r) mu= standard gravitational parameter
Period = T = 2pi*sq root(r^3/mu)
r = radius of orbit = altitude + radius of earth
mu = Newton’s universal gravitational constant x mass of planet
A geostationary orbit is 35,786 km from the equator. The orbital period is 23.93 hours, or 23 hours 56 minutes which is the time it actually takes for the earth to complete one rotation. The reason we normally count 24 hours as being one day, is because 24 hours is the precise time the sun is at the same spot in the sky every day.
To got into its orbit, the satellite is launched on a rocket. In the United States, one workhorse rocket has been the Atlas V. It weighs 700,000 lbs at launch and can lift 28,000 lbs to geostationary orbit. The main engine is powered by liquid oxygen, the oxidizer and RP-1 - which is form of kerosene, similar to jet fuel.
Rocket engines are an application of Newton’s third law, for every action, there is an equal and opposite reaction. The combustion of fuel causes high pressure exhaust gases to be expelled at supersonic speed. The rearward acceleration of the mass of the fuel leaving the rocket nozzle causes the equal and opposite reaction of forward thrust powering the rocket upward.
Maintaining a stable straight flight comes from swiveling the thrust nozzle to keep it stable. This is called gimbaled thrust.
A geosynchronous orbit is achieved in stages. Typically, the rocket takes the satellite on its orbital altitude, but the initial orbit is elliptical. This elliptical orbit has to be changed to a circular orbit to become geostationary. The satellite continues on an elliptical orbit until accelerating the rocket at precisely the right time during its trajectory forms a circular orbit at the geostationary distance, which is at 35,786 km above the earth’s equator. There is no other geostationary orbit.
Since there are 500 satellites at that altitude, the real estate is limited. This real estate at the geo stationary orbit is tightly controlled by an organization called, the international telecommunications union (ITU) which assigns each satellite a slot at this perimeter.
In addition, unless the rocket is launched from somewhere in the equator, it will have an orbit that is not quite geo stationary because it will not be in line or in the same plane relative to the equator. So for example, when satellites are launched from Cape Canaveral, which is located at about 28.5 degrees north latitude, the orbit will be inclined 28.5 degrees from the equator. This has to be adjusted, in a directional change requiring fuel. Thus, it is beneficial for countries to launch their rockets as close to the equator as possible so that less rocket fuel is needed to make this adjustment.
The first thing that happens after a satellite reaches its permanent orbit is that solar panels are deployed so that the satellite can have power to function. It orients itself relative to the sun and the earth, and establishes communication links. The main function of the satellite is to receive signals from earth mainly in the form of radio transmissions, amplify them, and relay them back at a different frequency back to the surface of the earth. The shift in frequency is used to prevent interference of incoming signals with outgoing signals.
#geostationary
#rocketscience
#satellites
Since radio waves are a form of electromagnetic radiation, same as visible light, they do not bend around the curvature of earth - photons are too fast after all, the job of the satellite is to transmit radio waves over long distances. Otherwise, this would require a string of thousands of relay stations on earth to do the same task.
Interestingly, a geostationary orbit is sometimes called the Clarke orbit, named for science fiction writer Arthur C. Clarke, who wrote 2001-a space odyssey. Believe it or not, he was the first person to detail the usefulness of such an orbit in a story he wrote back in 1945. - วิทยาศาสตร์และเทคโนโลยี
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Love , blessing and praise from India🇮🇳
You must be from up north, people from south India look horrible. Love from Indonesia 🇮🇩
@@yetygamer94 Maybe u have some bad experience with South India. Sorry for that but people from South India also look good.
@@yetygamer94 u guessed it right....but south indians do look beautiful.....and are undoubtedly the most honest , innocent, intelligent people across the globe..
@@yetygamer94 what's wrong with you mate, this is a science channel not a cosmetic shit show or some shitty social media platform where stupid people are all about looks. You should know better earlier humans were Africans and its not because our look but of our mind and intellect qualities that we humans have reached where we are now.
@@yetygamer94 hey listen...i think you should scrap your comment...
Dr. Ash- as an educator, I have to say I love, LOVE your explainer videos. This video, for example, or the "all physics in 20 minutes" are amazing. I'd be in awe if you resumed making these types of videos.
Fascinating. I always learn something new off Arvin!
I looked up how many countries are on the equator. There are 13: Ecuador, Colombia, Brazil, Sao Tome & Principe, Gabon, Republic of the Congo, Democratic Republic of the Congo, Uganda, Kenya, Somalia, Maldives, Indonesia and Kiribati.
If I was running one of these countries I’d try to take advantage of my geography to establish a low cost commercial rocket launch industry. Or maybe persuade the other 12 in to some kind of club of equator-based nations to pool resources.
The Latin American countries on the equator could cater for the Americas, the African ones for Europe and the Asian ones for Asia.
Now, you're thinking like an entrepreneur! That's a good idea. There are probably some technical barriers to this, but worth exploring for those countries.
Arvin Ash
Technical barriers, yes...but it’s only rocket science! 😁
Well, European satellites are launched from Equatorial Guinea, a French colony kept pretty much for this purpose alone. Then there's the possibility to launch from ships, which have some advantages, such as not having to ship the rocket as far, and having a ready source of hydrogen and oxygen by electrolysis of water. Furthermore you are generally limited to launch-sites at the east-coast, as having a lot of empty space (ocean, desert, uninhabitated mountains) to the east of your launch site is useful, since you tend to drop spend rocket stages there.
@@ArvinAsh sir can u kindly make detail Courses In different science topics in future in this Channel from Basic to academic research
Good Day Mr Arvin, on Video 9:45 stated KSFC AT Florida is at 28degree Latitude, do we need to add 23 degree to IT as Our earth tilted 23 degree? I mean here the ecliptic plane is same as equatorial plane or am i wrong?
Arvin Ash has amazing communication skills.. He is like a big communication satellite 😀😂
lame comment
And I have poor communication skills.
_The questions are: “WHO are his employers, and is HE telling us the TRUTH?_
_All those guys explain phenomena and things, as if their audience were retarded kindergarten kids._ _Little colored balls in kaleidoscopic graphics, unrealistic swarming of satellites around the globe, teaching people platitudes as: “When you are watching the weather forecast you are connected with a satellite._ _After all it’s ROCKET SCIENCE, and you as a US Citizen ought to be proud of it, very, very proud._ _The prouder the better, and easier to bamboozle._
_When you explain Newtons Third wrongly, then rockets can fly in a vacuum._
What a great video Arvin. All the answers about geostationary orbits of satellites we wanted to know. Clear animated graphics helped me understand all the difficult bits about orbits and where satellites are placed to be so useful. Great. Thanks.
Thank you, Mr Ash. I learn so much watching your videos
Thank you, sir for explaining complex issues in a simple and lucid manner. 🙏
Arvin, your videos are exceptional. So well presented. Thanks.
Great video arvin! :D Keep up the good work
This is becomming one of my fav channel.. Tq u sir💝
On of the best teachers I have seen so far.
Thank you sir.
In school I was great at geometry, ok in algebra, bad at trigonometry, and I flunked calculus. But thanks to TH-cam in just 13 minutes I'm a rocket scientist. My how we have progressed.
lol
time to get a job in the space industry then!~
there is no way btw, that you can just be "ok at algebra, bad at trigonometry and flunk calculus" and actually fully understand and be able to manipulate and solve problems using the mathematics in this video...., I understand you might be joking but I just figure i might say it anway. not to mention all the chemistry and other subjects ect ect in this video
@@neonblack211 Of course I'm just joking. Except about flunking calculus.
Apparently, even rocket science is not quite "Rocket Science"
Why you're so accurate..
Lol
After two years, I have watched this video the second time. It is a pleasure listening to you.👍
He is a wonderful communicator. So lucid in whatsoever explains, be it quantum physics, or cosmology or rocket science. 👌 I didn’t know that Arthur Clarke had anticipated the geostationary orbit. Good enlightenment.
Stunning presentation!
If you're looking for ideas for future videos, I would personally love to know more about the debris orbiting earth. How much space junk is up there, what kind of obstacles does this present current and future generations of space explorers/pioneers, and what actions are being taken or are under (serious) consideration for dealing with this problem? I am super curious as to the sheer amount of stuff that's orbiting earth, functional or otherwise. Great video as always, thanks for your work!
What a clear presentation . Thanks man.
2 interesting things to add.
1. The use of an elliptical orbit to reach a circular orbit (as shown in the process used to reach geostationary orbit) is called a Hohmann transfer
2. A rocket engine becomes more efficient the at faster speeds (relative to the earth), since the lower your altitude, the faster your speed this means that the most efficient place to use the boosters is at the perigee.
This is called the oberth effect
Interesting. Thank you.
Another way to think about it: Work = Force X Distance.
Rocket engines apply a constant force regardless the speed that the vehicle is travelling.
So, when the engine fires at higher velocity (for the same duration) the force is applied over a longer distance resulting in more work being done.
_The best way to get out of reach of a Force is not orbiting around it, but in distancing yourself from the Force perpendicularly._
U cant accelerate a rocket in space
@@yasirpanezai5690 So if a rocket PUSHES mass out the back that will NOT propel the rocket forward?
Maybe you should review Newtons Laws?
A very very very informative video, thanks a lot sir for sharing your wonderful knowledge with us too.
Addicted to your videos...❤️💯
Such a superb video. Thank you 🙏
Very clean and concise explanation 😇
This is the best clear explanation with excellent animations about rickets and launching satellites... I am thankful to Arvin Ash for this wonderful presentation which I am sure many like me have enjoyed watchibg. Super explanation better than the lectures of MIT and Stanford and Caltech.
Amazing video. Thank you.
I always wait for ur video arvin ❤️
Great explanation,, this is a so worthy video..
Expecting videos just like this
Hey. Love the way you explain. So can you please make more videos about rocket science?
Great video, learned a lot
Some 20 years ago my director said to me "This is not rocket science. We know how to build rockets but we don't know how to do "... In the first moment I was shocked as I did not expected the turn he put into is words. Then I laughed out loud. ;-)
Sometimes, you have to turn the problem on it's head, and see it from a completely different pov, in order to solve it. ;)
Thank you Arvin.
Very nicely done !!
Thank you! Cheers!
Nicely explained... 👌
Very good video. Thanks.
Another great video Arvin! I came across the wikipedia page for tachyons this evening which I found interesting, I know that most physicists don't believe they exist, but they and other hypothetical particles might make for a good future video.
That's a good idea. I just noted it down on my list. Thank you.
@@ArvinAsh Thanks!
Beautiful explanation
excellent information.
A small typo error ....at 1:53 the figure shows 36,786 kms for Geostationary orbit distance....it should be 35,786 kms.
What a talent you have.
Wonderful video.
Excellent explanation. As simple as rocket science 😁
Great explanation
Great video
Great explanation as always, I guess Rocket science is easier in theory than on practice. Can you please make a video on ultraviolet catastrophe.
Yeah that's the thing. It's one thing to calculate clean Newtonian orbits, and use the odd classical equation here or there. Rocket science is at most moderately difficult at that level of analysis.
But it's an entirely different story to actually build a rocket and get it into space... Many complications we don't consider in elememtary context, like air resistance at launch, come into play.
The only thing I can think of that genuinely is even more complicated is making micro chips.
very good presentation
Very interesting.
What a fantastic explanation! as always. Now I know Rocket science. Lol
However, I'm still waiting for the video on quantum computing, as promised! @arvin
How satellite rectified radio waves? And how satellite knows where to deliver signals?
By the way great video
Thank you sir for great video
Thank you! 👍🙂
Nice video Arvin. It could be better ,but rocket science is a tough subject.
Excellent.❤
I'm glad you referenced Arthur C. Clarke and the Clarke otbit. Now if we could just get remote operated manipulators to be called Waldos. They used to use the term in the early nuclear industry to remotely handle radioactive materials. Not sure whether the term is still used.
Teacher: this is not rocket science
: wait it is
I really need it
Sooo, after take off...what next? :D This is not designed to be disrespectful; the manner by which complex concepts is explained was clear and concise. Ash's ability to explain the physics and science is always a pleasure and the wannabe space man inside of me thinks pretends he fully understands. Now, I'm going to read the manual for my new toaster
Great video, it really flowed for me and you wrapped it up quite nicely....one of your best I have seen for sure. @ 1;35 you had an animation of 'space junk'...I would love to see you do a video on that subject, possibly combined with the number of satellites that have been launched in 50+ years and where is all that metal? I find the subject very fascinating. I saw a doc. about it last year about all the different solutions a few companies have to clear it, space nets etc.
Awesome, thank you! Interesting idea. Will put it on my list.
As we know the axis of earth precesses then does these satellites also have precessional motion or not?
Yayyy now I know rocket science 🥰🥰
Do we have an orientation of rocket path such that it moves from north pole to the south pole and to north pole again?
Sure, you can put satellites in that orbit. I am not sure how many or if any are in that orbit currently.
What about the Sagnac effect? Wouldn't be worth mentioning the Sagnac correction that is built into the GPS...and what would happen without it? Or, is it beyond rocket science?
Nice ❤️
Thank you for the great video Arvin. Can I ask why there is a phenomenon called escape velocity? I why wouldn't any prolonged velocity not eventually leave the earths atmosphere?
I think what you mean is any prolonged *acceleration* (because if you want a constant velocity on earth you need to accelerate to stop drag and gravity from pulling you back), and yes, if you are constantly accelerating you will eventually leave the atmosphere.
But escape velocity is not about leaving the atmosphere, it's about leaving the earth's gravitational field. Escape velocity is the speed you need to go at so that the earth's gravity will never be able to pull you back towards it.
The centrifugal force of the rotation is balanced perfectly against the pull of gravity. The higher the orbit the less speed is needed. The lower the more speed. Your question is very valid indeed you are a thinker. If the balance is not perfect and it could never be, an increase in altitude would cause a loss of orbit because at the higher altitude the speed would be to high. This would mean the centrifugal force was greater than the gravitational pull. Its most likely to be the other way round however. A loss of speed due to atmospheric drag would slow the craft. Bthis would then decrease the centrifugal force and increase gravitation pull. This would in turn produce more drag less speed more gravity etc and so on. Boasts to maintain orbit would necessary and enough fuel could never be available. So you question is excellent it can't be done
Hi Arvin! Their are a couple of questions which I've been trying to solve for months.I hope you can answer them in the most simplest way.
Q.1) If atoms are dead then how we are alive? because we are made up of cells which are alive but cells are made atoms which are dead (cells - protein - amino acid - nitrogen and carbon atoms). Q.2) If universe is expanding then what is it expanding into?
Q.3) What's inside the Bermuda Triangle, because recently a strange thing happened in that.Trying to write in short. A pilot went into it........................ and he reached his destiny which was around 4 hours far from him in only 30 mins.
Q.4) How did the first particle of big bang came into existence?
It depends on what you mean by "dead" -- atoms are active with energy. This energy combines with other atoms to make molecules which form the basis of chemistry, which forms the basis of life. Universe doesn't expand into anything, Bermuda triangle is just a very large region of the ocean. There is nothing special about it. Not currently known what happened before the big bang.
@@ArvinAsh Thanks Arvin!
@@Paradox1606 The Bermuda Triangle is like Arvin explains just a section of Ocean which is defined by 3 Landmarks. The special part of it is that lots of ships have sunk there which is probably related to weather like wind creating huge waves and strong water currents. There are claims that airplanes instruments get affected by magnetic forces which may leave pilots disoriented and in bad weather conditions lose their bearings. The Big Bang and expanding Universe are theories which try to explain the nature of things.
Actual Rocket Scientist here, aerospace engineering is consistently considered to be one of the hardest degrees to complete.... HENCE the colloquialism.
My question is: what types of material are being used is these satellites, and what are the boundary conditions to operate at this such altitude?
Thank you in advance. Please suggest me reference articles or book, if possible.
Sir....
It's not as simple as it looks..... It's a very tricky and complicated subject in Aerospace Engineering..... 🙏🙏🙏🙏
It means if you set a proper radius with blackhole orbit. You can you can rotate objects with same time as blackhole rotate around the galaxy? As geostationary mirror the earth rotation
I never knew that all geo-stationary satellites are at the exact same altitude.
@arvin
Can you use moon's gravitation to support a rocket launch? If yes, woudn't it make more sense to execute rocket launches in the night time?
It would not have much effect because the moon pulls the earth along with the rocket on the launch pad. I suppose there is somewhat of a pull from the moon on the spacecraft, but it is so small at this distance, that it would be negligible. You would only feel the effect of the moon on the spacecraft if you were much closer to the moon.
There are many things that keep Rocket Science hard. I'll drop some names: Rocket Equation, Specific Impulse, Chamber Pressure, Vacuum Optimization, Planetary Slingshot Manoevre, Hohmann Transfer Orbit.
2:06 well that particular point in space is only the same point relative to the rotation of earth. Counting earth's orbit around the sun and the sun's orbit around the galaxy it's a very complex trajectory that the satellite takes.
5:21 "high pressure exhaust gasses" - my understanding is that ideally the exhaust gas pressure should be the same as the surrounding atmospheric pressure to extract the maximum efficiency from engine. The engine bells have that shape so the gasses are expanded as close as possible to surrounding pressure. Over expansion or under expansions results in lower efficiency.
Yeah, and that’s why the nozzles for the first stage, used in atmosphere, are a different shape than the ones on later states operating in space. Everyday Astronaut has some great videos about this.
I hope all physics teacher to be like him, make it alot easier
This is beyond rocket science...
Nice vid, but i have to disagree on the 4sec distance of the satellites. If each satellite orbits at roughly the same speed of ~3.6 km/s the delta v between a set of satellites is almost zero or just a few m/h, so if they are parked at a distance of 10 km it would take much longer for them to collide and small corrections in speed are enough to correct it, or do i miss something?
We love you harry bellefonte 👌
You also need to set the satellite in rotation of 1 rotation per day to keep it aimed at the earth, right?
Yep, while the solar panels alway need to be facing the Sun. I didn't get into the mechanism of this, but it is also interesting.
I have a question . Why the exhaust's (i don't know exactly what we call the fire behind rocket😅) flame isn't blue eventhough it contains liquid o2🤔. I mean o2 emits the blue flame, isn't it.
Depends on the oxygen to fuel ratio.
and fuel type.
Blue flame is only caused when the fire is so intense and so hot that it causes the air molecules around it to glow a blue color
So as for your question, just like he said
It depends on the ratio of the oxygen/fuel you used, plus no one would dump all oxygen into the combustion chamber right away to waste all the oxygen, instead they poured the oxygen in bit by bit with a certain ratio to prevent running out of oxygen before burning all the fuel
My favorite phrase - accidentally used by a host on a home improvement show years ago “It’s not rocket surgery”.
I'm still can't quite put it together. I understand it whilst you're explaining it but as soon as the tutorial is over, it's still rocket science to me. Lol
That's why it;s called Rocket Science brother!
Agreed. What's not rocket science is the name Cathleen equates to " sister" as in female. Lol
@@cathleenwilliamson6668 Oops. I'm literally gender blind. Does that make me woke?
Arvin Ash, nope. Just gender blind. Lol. You're a good guy though.
If you can understand it during the explanation, then you can learn it. It's really a matter of watching a presentation a few times and absorbing more information each time. In the end, you remember the details.
I love astronomy and space technology
Next you can try explain how make round low level orbit in the moon? Apollo made it and others. Barycenter probably make something difficulties because orbit is elliptical and not moon centered.
wow we owe all of these to Watt model of early lokomotive .
or better to put it the whole history of science .
GREAT
2:45 The formula looks extremely similar to the formula of the period of a pendulum in a gravitational field in classical physics.
I also noticed that 😄
Subbed
You should explain the Einstein s photoelectric effect
Rocket science nicely explained... When you explain things we understand them better😁
What are cryogenic and thermal fuels Arvin??
I have seen some depiction of orbital paths as Snaking thru the orbital plane , undulating left , and right [ ~~~~ ] as a snake moves . 1) Is this an accurate depiction? 2) What were they trying to depict if it is not accurate ?
If I understand what you are talking about correctly, the depiction you are talking about presumes a fixed reference frame. I don't think such a frame exists in space-time.
I was ever wondered how do we measure the speed of any object moving in an empty space travelling straight as if there is nothing else near around to measure it with.
My son's favorite movie was Jimmy Neutron Boy Genius. When they are getting the carnival rides read to chase the space alliins that took their parent, Jimmy makes the statement "it isn't rocket science. wait yes it is." It has been a running joke in our family for years. My son ended up getting an Airo Space Engineering degree from NC State. He was on the competitive rocketry team for four years. I remember the math involved in the rocket they launched. I cannot even imagine the math needed for the satellites. I do like your videos.
Thanks
Do geostationary satellites have exactly 0 eccentricity or just an extremely low one? Being able to match perigee and apogee exactly seeks impossible
from looking at a satellite tracking website, it seems that they just have a very low eccentricity, like a 8-10km difference between perigee and apogee
In point of fact, actual "geostationary" orbits are practically impossible for at least two reasons: The Moon, and The Sun. Each of those exerts a significant gravitational force on the satellite which work against the Earth's pull, and this causes the satellite to drift out of even a perfectly positioned orbit over time. As such, onboard fuel/thrusters are needed to counteract this over the life of the satellite & maintain its spot in orbit. Fun Fact: in animations/visualizations of orbital objects around the Earth, you'll see not one, but two belts near the equator: the one directly over it is for active sats; the inclined orbit is a "graveyard" orbit which is where those sats end up when they can't maintain their spots any longer. =)
Also Satellites in orbit are losing time not because they are outside of
gravity but because they are moving fast. Its a lot faster then we are
moving but it is a small fraction of the speed of light thats why the
time lose is small but it is noticeable. Speed not gravity causes the time dilation.
Sir arthur . C. Clark was an hounorable srilankan citizen.im proud of that. There is a satellite center named of his name for hounour.
Wow, u made rocket science quite simpler.👍👍
Just as a helium balloon rises could there be a way to take a small satellite up at least to a low gravity altitude with a large lighter than atmosphere balloon, where a smaller rocket could then take it to the geostationary orbit? I'm not trained in physics so please accept my apologies in advance if this is a really dumb idea and question.
Arvin proved that there is no such Rocket science to understand Rocket science.
How do you keep all of this in your head?
Does anybody know about how many satellites we had in orbit around 1965-66? I have a good reason to know and I'd be happy to share after I know the approximate answer. Thanks.
Please make video on latest discovery of possible life on Venus and what kind of life could it be