James Webb Space Telescope

[☎need4naiim☎]

NASA's dedicated JWST page:
https://www.jwst.nasa.gov/index.html


Ladies and Gentlemen;

After 25 years of unbelievably detailed level of engineering, NASA has launched the most powerful space telescope ever made, in collaboration with ESA and Ariane Team. The worthy successor to the iconic Hubble Space Telescope is now on its way to the L2 orbit after a perfect launch on Christmas Day. Called the James Webb Space Telescope, JWST promises to transform the way we study the cosmos. It is also called as "Time Machine" because it MAY change the known Age of Universe by catching the lights which are even older than 13.8 billion years.

I have made this thread as a place to share all-new "historical" news and unbelievably detailed photos of distant cosmos that will hopefully come from the telescope after a successful launch and an unfurling process that will take up to two weeks to complete.

After its launch, this telescope will go to a distance of 1 million miles away from Earth (unlike Hubble Space Telescope's 547 km) to the Lagrange Point 2 (L2). The Webb will orbit the Sun near L2, a gravitationally stable solar orbit that's roughly 1 million miles from Earth, on the opposite side of our planet from the Sun.

This is an extremely complicated launch and mission, with many opportunities for things to go wrong during the processes. But if everything goes right, the world’s astronomers will have an incredibly powerful tool at their disposal for the next 5.5 to 10 years.

JWST is equipped with enough tools and machinery to unravel more mysteries of supermassive blackholes, distant alien worlds, stellar explosions, Dark Matter, and possible new planets or moons of known planets in Solar System.


It is said that it can spot a stationary bee on the surface of the Moon. It is claimed that JWST can spot which seat a person sits in a hypothetical car on the surface of Pluto. Can you believe that? 👀

Since i can't write every little aspect of this telescope here, one by one, you can read a more detailed description in these links:

https://www.theverge.com/22826899/james-webb-space-telescope-jwst-launch-mission-what-to-expect

https://spaceflightnow.com/2021/12/23/webb-telescope-is-a-time-machine-for-astronomers-to-see-the-cosmic-dawn/

NASA TV’s provided live video coverage of the Ariane 5 launch with JWST at 3 a.m. EST (08:00 GMT) on Dec. 25 2021. You can directly reach NASA TV from here, anytime:

https://m.youtube.com/watch?v=21X5lGlDOfg



This will be the most important space mission of this Century if JWST can operate smoothly on its orbit. 🚀

[RRW359]

Messaggio originale di Tiberius:

Messaggio originale di Ⓜ Ⓐ Ⓢ Ⓠ Ⓤ Ⓔ:

Not to minimize the issue *too* much, but I think we laypersons tend to underestimate the scale of it all, when it comes to space junk, and the relative size of the sphere in question, which has, by its very nature, a greater diameter and far more area than even the surface of the earth.

Sure there's a lot of space junk, but there's also a lot of space between it all. More, I think, than most people can even imagine, even if they squint and try to think really hard about it. It's not to the point where it's super dangerous to go up, like Frogger in space or anything.

Its just space junk that are travelling more than 15000mph. Nothing to worry abt

If both space junk and satellites are traveling at about the same speed doesn't that mean they are relative?

[Tiberius]

Messaggio originale di RRW359:

Messaggio originale di Tiberius:

Its just space junk that are travelling more than 15000mph. Nothing to worry abt

If both space junk and satellites are traveling at about the same speed doesn't that mean they are relative?

Yea they both totally go on the same direction. Nothing to worry about

[RRW359]

Messaggio originale di Tiberius:

Messaggio originale di RRW359:

If both space junk and satellites are traveling at about the same speed doesn't that mean they are relative?

Yea they both totally go on the same direction. Nothing to worry about

Also they're all at the same height, right? And orbits like the ISS don't need regular boosting or anything to stop them from crashing back to Earth.

[davidb11]

Guys, none of the objects currently floating around Earth are going 15,000 miles an hour.
That's not how physics work.

Besides, there's still too much empty space.

Just like a rogue star, Neutron or other wise, we have no reason to worry about junk in space causing problems right now.

[Rumpelcrutchskin]

Messaggio originale di davidb11:

Guys, none of the objects currently floating around Earth are going 15,000 miles an hour.
That's not how physics work.

Besides, there's still too much empty space.

Just like a rogue star, Neutron or other wise, we have no reason to worry about junk in space causing problems right now.

Actually that`s exactly how physics works, all that junk orbits around there with speeds up to 28K km/h so even very small object can have a pretty big impact. International space station has been hit with couple of those tiny debris leaving behind craters in the solar panels and even crack on the observation dome window that looks like someone took a shot at it.

[davidb11]

I don't know how it's possible for any of those objects to get that fast.
That makes no sense to me.

Every object in orbit can't become that fast.
Space has no decay of momentum.
So, nothing can become slower than what it first started at without being acted on by an outside force.

Nothing can become faster than it started at either without an outside force.
Nothing in space around Earth can be travelling at 28 Thousand KM an hour because nothing in orbit was ever travelling that fast.

[Rumpelcrutchskin]

Messaggio originale di davidb11:

I don't know how it's possible for any of those objects to get that fast.
That makes no sense to me.

Every object in orbit can't become that fast.
Space has no decay of momentum.
So, nothing can become slower than what it first started at without being acted on by an outside force.

Nothing can become faster than it started at either without an outside force.
Nothing in space around Earth can be travelling at 28 Thousand KM an hour because nothing in orbit was ever travelling that fast.

You realize that Earth`s escape velocity is 40320 km/h, that`s just to get off the ground and into the orbit.

[Pocahawtness]

Messaggio originale di davidb11:

I don't know how it's possible for any of those objects to get that fast.
That makes no sense to me.

Every object in orbit can't become that fast.
Space has no decay of momentum.
So, nothing can become slower than what it first started at without being acted on by an outside force.

Nothing can become faster than it started at either without an outside force.
Nothing in space around Earth can be travelling at 28 Thousand KM an hour because nothing in orbit was ever travelling that fast.

But the space station is travelling at 17000 km/h and the escape velocity of the earth is 40,000km/h ( the speed you need to get to to go to the moon ) so it's not really difficult to imagine that some objects are doing 28,000km/h.

[Devsman]

Ok lemme clear some things up here.

First:

Gravitational orbit is the situation in which an object falls with the same acceleration as is required to travel in a circle.

Gravitational force is modeled by the law of universal gravitation, F = -Gm1m2/r^2, where G is the universal gravitational constant, the m's are masses, and r is the distance between them.

Dividing out mass, which we can do since we're discussing matter, which by definition cannot have 0 mass, we get a = -Gm/r^2, where the remaining m is (in this case) the mass of Earth.

Centripetal acceleration is defined by a = -v^2/r, where v is velocity (fun fact, there's a really underrated form of this equation that is fantastic for working with space elevators and other really really tall structures, a = -r(omega)^2, where omega is rotational velocity).

Setting them equal to each other gives us the fundamental formula for gravitational orbit: -Gm/r^2 = -v^2/r. A little algebra later: Gm = rv^2

Gm is roughly 4*10^14 m^3/s^2, and the lowest possible r (to not be underground or something stupid) is around 6500 km, so the fastest possible orbit is about 7800 m/s, or about 28000 km/h.

Second:

Outer space really isn't as ideal for motion as it seems. Certainly not near Earth. The Earth-orbiting system will radiate its velocity (albeit extremely slowly) out until failure via gravitational waves, whose existence were hypothesized by Einstein and finally detected by LIGO in a test run from September 2015 to January 2016.

In addition to that, there's also a miniscule (as in so small it's hard to measure) atmospheric pressure that is believed to be present in even the remotest places of the universe. Near Earth, it's definitely larger. This could theoretically cause drag.

Third:

Escape velocity is not the velocity required to reach orbit. Escape velocity is the velocity at which, if you were to stop pushing exactly at the surface of the body in question, the moving object would continue moving away indefinitely (as opposed to sub-escape velocities, where it would eventually come back down).

It's really more a statement about the body's (in this case, Earth's) gravitational energy, just stated in kinetic terms. It's equivalent to, if we dropped a ball from infinitely high, how fast it would be going when it landed.

By integrating force over distance (this being how energy is calculated in general), from the radius of Earth to infinity, we can arrive at the total gravitational energy. The mass being constant with respect to r, we can cancel it when we determine the velocity represented by the statement of this energy in kinetic terms, according to K = 1/2 mv^2. I'll spare you the calculus (because my phone doesn't have the symbols for it) and just drop the resultant equation v = sqrt(2Gm/r), which for Earth, is about 11.2 km/s, or about 40,000 km/h.

This is much higher than our earlier calculation of the fastest possible orbit.

[Pocahawtness]

Very Newtonian.

[davidb11]

Alright. I think I get it now.

[Pocahawtness]

Messaggio originale di davidb11:

Alright. I think I get it now.

Just remember that is for the purposes of calculation and isn't what is happening at all, lol.

[Devsman]

Messaggio originale di ｢C❤️A｣ Pocahawtness:

Messaggio originale di davidb11:

Alright. I think I get it now.

Just remember that is for the purposes of calculation and isn't what is happening at all, lol.

Yes and no.

It's just a model, but it's a pretty good model.

[Pocahawtness]

Messaggio originale di Devsman:

Messaggio originale di ｢C❤️A｣ Pocahawtness:

Just remember that is for the purposes of calculation and isn't what is happening at all, lol.

Yes and no.

It's just a model, but it's a pretty good model.

Mathematically, yes, but it does nothing towards understanding what is really going on. To me the why was always more important than the what!

[Tiberius]

Messaggio originale di RRW359:

Messaggio originale di Tiberius:

Yea they both totally go on the same direction. Nothing to worry about

Also they're all at the same height, right? And orbits like the ISS don't need regular boosting or anything to stop them from crashing back to Earth.

no they're not. i was being sarcastic. do you honestly think space debris and satellite travel on the same trajectory? smh