If there are aliens, what will they look like?

[Jstpssng]

Believe in MAGIC It is all around.

Next you will be telling me to believe in luck.
While I do agree there are many things we don't understand, I don't believe in either of the above.

 

[CalG]

Next you will be telling me to believe in luck.
While I do agree there are many things we don't understand, I don't believe in either of the above.

I just thank my lucky stars that all my guardian angles keep working overtime! With short pay!

Now.. numerology ....that is the future

But, have you ever stopped to consider that astrology is BASED on observation of events, then finding the position of the celestial entities after? NOT the other way round. NO PREDICTIONS ! It's all bastardized now, people being what we are.

As Voltaire once wrote to his king. "I have studied it, and You have not!

Just for a moment, THINK of the possibilities!

Angels fly because they take themselves lightly!

Better yet is from "The Little Prince" by A. de Saint- Exupery

"What is Essential, is invisible to the eye. One sees rightly only with the Heart"


This is a comic relief thread ...Right? Aliens appearance and all....

Next you will be telling me to believe in luck.
While I do agree there are many things we don't understand, I don't believe in either of the above.

What do you think of the "Multi-verse hypothesis" ?

If you follow the science, which I am sure you do ;-) The math indicates "IT MUST BE SO".

Quite a stretch "to the untrained eye"

On a side note. Can you imagine, the ocean depth at the very edge of this flat earth is still more than 10,000 feet!

How do they keep all that salt water from spilling over the edge? a flimsy ice wall?

Must be aliens!
;-)

 

[Jstpssng]

I just thank my lucky stars that all my guardian angles keep working overtime! With short pay!

Now.. numerology ....that is the future

But, have you ever stopped to consider that astrology is BASED on observation of events, then finding the position of the celestial entities after? NOT the other way round. NO PREDICTIONS ! It's all bastardized now, people being what we are.

As Voltaire once wrote to his king. "I have studied it, and You have not!

Just for a moment, THINK of the possibilities!

Angels fly because they take themselves lightly!

Better yet is from "The Little Prince" by A. de Saint- Exupery

"What is Essential, is invisible to the eye. One sees rightly only with the Heart"


This is a comic relief thread ...Right? Aliens appearance and all....

What do you think of the "Multi-verse hypothesis" ?

If you follow the science, which I am sure you do ;-) The math indicates "IT MUST BE SO".

Quite a stretch "to the untrained eye"

On a side note. Can you imagine, the ocean depth at the very edge of this flat earth is still more than 10,000 feet!

How do they keep all that salt water from spilling over the edge? a flimsy ice wall?

Must be aliens!
;-)

You're starting to make a believer out of me! Please tell me, if you can; how far to the point of know return?

 

[BravoXray]

Oh come on, don't be such a spoilsport. Everybody loves a good conspiracy theory. Next you'll be telling us that JFK isn't living on a tropical island with Elvis and Marilyn.

No, conspiracy theories aren't harmless.
Remember the moron that drove to a pizza joint and shot it up because he believed the conspiracy theory that Hillary was holding children in the basement for satanic rituals and sacrifice.
Too many people don't have the cognitive ability to separate fact from fiction to call conspiracy theories harmless.

 

[BravoXray]

I can see it's really not much use to respond to your posts...
Better to just ignore them, I'm afraid

I told you so!

 

[Jstpssng]

No, conspiracy theories aren't harmless.
Remember the moron that drove to a pizza joint and shot it up because he believed the conspiracy theory that Hillary was holding children in the basement for satanic rituals and sacrifice.
Too many people don't have the cognitive ability to separate fact from fiction to call conspiracy theories harmless.

Then there are those who can't recognize a joke when they see one.

 

[MossRoad]

3) Long distance shooting (battleships, snipers) do not take into consideration the supposed rotation of the earth.

Long Range Shooting: External Ballistics - The Coriolis Effect

Master long-range shooting by understanding the Coriolis effect. Our expert guide explains how to adjust for optimal accuracy.

thearmsguide.com

From:

Ballistics

In the northern hemisphere, the trajectory will be deflected to the right. A projectile traveling 1000 m/s due north at latitude 30o N would be accelerated to the right at 0.07 m/s2. For a 30 second time-of-flight, corresponding to about 30 km total distance traveled, the projectile would be deflected by about 60 m. So for long range artillery, the Coriolis correction is quite important. On the other hand, for bullets and water going down the drain, it is insignificant!

Bruce

That's a very informative and easy to understand article. Thanks.

It also debunks the bunks.

 

[MossRoad]

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QUESTION #221

previous | next​

If space is a vacuum, then how do space capsule's retrorockets steer?​

Asked by: Mr. Wood

Answer​

The fact that space is a vacuum nicely isolates this problem as a demonstration of Newton's third Law, commonly phrased as 'every action has an equal and opposite reaction.'

It is not necessary for the rocket exhaust to push against anything EXCEPT THE SHIP ITSELF. You see, when the combustion of fuel takes place inside the rocket (think of a long vertical cylinder with the 'bottom' open) the exhaust gasses produced expand quickly in all directions. The molecules slam into anything in their path exerting a small force each. Thus some molecules push against the 'right' side and some push against the 'left' side, and all these sideways forces cancel each other out. Some molecules slam against the 'top' of the cylinder, but since there is no bottom of the cylinder, there is no force to cancel this out! Therefore the net force will be in the 'up' direction.

Another way to think about the situation is as a conservation of momentum problem. Any isolated system will conserve total momentum. Thus if you imagine a stationary ship, plus the fuel and oxygen molecules on the ship, p=0. If a few trillion atoms of exhaust are shot in one direction into the vacuum of space, the rest of the ship must move in the OPPOSITE direction with the same momentum (mass x velocity)

You can simulate this situation by throwing some bean bags (or bowling balls, or any other objects you have lying around) in one direction as you sit in a chair with wheels or stand on roller blades or ice skates. Whatever direction you push on the object, the object will push back on your hand with the same force, but in the opposite direction. Therefore you and the object you throw will move in opposite directions.
Answered by: Rob Landolfi, Science Teacher, Washington, DC

Retro-rockets are usually used to decelerate, not steer, a spacecraft. They operate like any rocket engine in the vacuum of space, by propelling gases in one direction to create an opposite and equal force on the craft. There is no need for air for those gases to 'push against' thanks to Newton's third law of motion.

'Steering' a spacecraft means changing its existing orbit or trajectory. That is usually done by using small attitude control rockets to point the vehicles main, larger rocket engine opposite to the direction you want to head. The main rocket engine is then fired to alter the vehicles original path. That same main rocket engine can be used as a retro-rocket by using the small control rockets to point it in the direction of motion before firing it.
Answered by: Paul Walorski, B.A., Part-time Physics Instructor

I've heard the bean bag analogy before. When you throw it forward while sitting on the wheeled cart, your body is pushing against the beanbag, not the air. The weight of the beanbag propels you backward before it leaves your hand. No air necessary to push against. Same thing with retrorockets. The force is pushing IN against the inside of the engine, not OUT against the vacuum of space.

Score another point for the debunkers!

 

[MossRoad]

Ya think we're gonna get in a brawl?

It would be less painful than the conversation!

 

[CalG]

You're starting to make a believer out of me! Please tell me, if you can; how far to the point of know return?

Well

In one of my early "science courses", (must have been biology) The teacher lined me up with one of the female classmates across the class room.
Instructing us both to "halve the distance between you two.."
This was repeated several times.

Then the lesson was given.

In Theory, by halving the distance between, the two objects will NEVER contact.

BUT

For all practical purposes, the two DO come in contact! I will attest to that! ;-)