If there are aliens, what will they look like?

[CalG]

Closer to home.

Hubble Space Telescope’s ACS Celebrates 20 Years of Ground-Breaking Discovery

The ACS continues to deliver ground-breaking science. When astronauts installed the Advanced Camera for Surveys (ACS) on March 7, 2002, the Hubble Space Telescope was already famous for taking deep images of the distant universe. ACS went even deeper, pushing humanity's view of the universe back to

scitechdaily.com

I was there in Florida for the launch of the STS-109 service mission. A guest of NASA. As close as a civilian could be . ;-) What a treat!

 

[MossRoad]

Sometimes I can't keep the made up science straight. Abra Cadabra! Gravity!

Got an answer to the Gravitational constant that I asked earlier?

Yeah. Stand right over there. Hold still. Here's what happens to you when earth's gravity lets go of the moon.

 

[otlski]

Gravity, or more appropriately called the acceleration of Earth's gravity, is roughly equal to 9.8 meters/sec^2. I use accelerometers often in my work and I can say without a doubt, I witness with my own eyes, that the acceleration of Earth's gravity is the same phenomena as rectilinear acceleration, just like Einstein's elevator thought experiment. I play around with these electro-mechanical accelerometers while familiarizing myself with the signs of their coordinate system, and in the process can say that the accelerometer cannot tell the difference between gravity and acceleration.

The centripetal acceleration at Earth's surface assuming a radius of 6400 km at a rotation rate of once per 24 hrs is 0.03 meters/sec^2. Earth's normal gravity at 45 deg latitude at sea level is 9.8 meters/sec^2. Thus, the force caused by gravity is several orders of magnitude greater the the force trying to throw water off the earth.

That is why the water does not fly off.

 

[Outinstickssnafu]

ruffdog wrote "Ummm....actually, like I said before, it is the magnetic field that protects the atmosphere. Mars doesn't have a mag field so they lost the atmosphere."

That's dragging the sun into the equation which wasn't what was being asked, and another level of complexity which considering even their lack of what an orbit is an pretty fundemental stuff that should be learned in basic engineering, well ... Oh and Mars has an atmosphere - lacking a decent magnosphere doesn't quite explain why the less dense gases have departed.


the old grind wrote "Nah, a troll would try to take over a thread and make it about him, her, or whatever gender aliens are."

Not happening at all :lol:

https://www.flamewarriorsguide.com/warriorshtm/troller.htm

Trad quipped "I get those responses fairly frequently. When people refuse to engage in civil discourse because they have their beliefs challenged. "

Well you may believe that to be the case ... Questioned instead of challenged would be a better fit there. I just wonder if you didn't have a stroke or something, because even for one ascribing the world to the product of an all powerful being, going on to undermine any genius on their part is ... not a very smart thing IMHO. That said you are losing both ways in the conversation here.

 

[MossRoad]

Gravity, or more appropriately called the acceleration of Earth's gravity, is roughly equal to 9.8 meters/sec^2. I use accelerometers often in my work and I can say without a doubt, I witness with my own eyes, that the acceleration of Earth's gravity is the same phenomena as rectilinear acceleration, just like Einstein's elevator thought experiment. I play around with these electro-mechanical accelerometers while familiarizing myself with the signs of their coordinate system, and in the process can say that the accelerometer cannot tell the difference between gravity and acceleration.

The centripetal acceleration at Earth's surface assuming a radius of 6400 km at a rotation rate of once per 24 hrs is 0.03 meters/sec^2. Earth's normal gravity at 45 deg latitude at sea level is 9.8 meters/sec^2. Thus, the force caused by gravity is several orders of magnitude greater the the force trying to throw water off the earth.

That is why the water does not fly off.

I didn't know there was going to be a quiz today.

 

[JasperFrank]

With all respects to what Carl Sagan tried to get across, I do like what this guy had to say about the subject. Good criticism is a touchstone of science.

 

[Rockbadchild]

it’s pretty hard to say as life can evolve in so many different ways as we have seen here on earth from the dinosaurs to us … but if i assume the evolution and natural selection follow the same path in other planet then ours i think the image we have in our head when we think of aliens must be close to it a biped with a large brain and small muscle mass upright standing is paramount to free the hands. If we think at our evolution, our head is getting bigger and bigger to a point that natural child birth is super challenging, so to accommodate that we have the most premature infant of all animals and if the female hip get any wider they won’t be able to run also we are having less and less hair and muscle compare to our ancestor so if that trend continue we ourself will look like aliens a whole lot… also if we get to a other planet and discover intelligent organisms the the aliens is going to be us.

 

[BravoXray]

Sometimes I wonder if someone is trolling for laughs or actually believes what they say.

Rarely do I hope they are trolling, but there are occasions.

That's why I put them on ignore. If no one responds to their trolling comments, they soon tire and hop on another thread and start trolling there.
There is absolutely no point to debating with someone who has only ever read one book that has all the answers.
Like the old saying, Never argue with and idiot, they will drag you down to their level and beat you with experience.

I'm glad I started this thread, the breadth of knowledge posters have demonstrated here is amazing.

I agree with a previous poster, aliens MUST have pointed ears or I will be sadly disappointed.

 

[CalG]

Amusing anecdote.

Many years ago...

My wife and I were traveling along the Blue Ridge Mountain Highway. (Unfortuantely after dark in the rain)

I was driving, and my wife was expressing some concern for the twisting, curvy roads and my choice of rate of forward progress. Knowing that a good set of tires were good for about .5-.8 g even on wet roads, I attempted to calm her by saying "When you feel about half your weight pined against the side door, That's when we need to start worrying about our cornering speed" . Needless to say, she was not thrilled with the metric.

"4 wheels are all wrong, they lean the wrong way"

On how does the air stay in close to the earth, It's all one big gradient.

 

[CalG]

That's why I put them on ignore. If no one responds to their trolling comments, they soon tire and hop on another thread and start trolling there.
There is absolutely no point to debating with someone who has only ever read one book that has all the answers.
Like the old saying, Never argue with and idiot, they will drag you down to their level and beat you with experience.

I'm glad I started this thread, the breadth of knowledge posters have demonstrated here is amazing.

I agree with a previous poster, aliens MUST have pointed ears or I will be sadly disappointed.

You are right!