Question Constellations/ Space travel

[Catastrophe]

I am rather surprised by your definition of "Universe". I was brought up to believe that Universe meant "all there is", not to mention all there was or ever shall be. Thus any system within "The Universe" might be termed "miniverse" or "semiverse" or possibly some other diminutive appellation. I find it very "off-putting" to see smaller or multiple versions of "all that exists" etcetera. Conversely, you might call "our Universe" by one of these diminutives, but then I suggest that that would be begging the question, in that some "clever" person might decide that the Universe was actually just part of something bigger.

 

[Catastrophe]

And, yes, there may be new components which then need to be incorporated. I do not mean to be unscientific, but there may be new mechanisms of telepathic contact which become accepted, for example, and these must obviously fall within the definition of all there is.
BTW, I do like your suggestions for defining modes of communication.

Cat

 

[DrRaviSharma]

I see two threads in conversation:

One thread deals with what is sensible (all sensors and eyes and of course our cognitive awareness and understanding) as The Universe. To them my question is that what appears today is not real as part of what we sense today did not simultaneously exist, these photons are from different times and appears as composite or mosaic of real sensible Universe.

Second presupposes the Big Bang.

My view:

If DM is permeating everywhere anytime and is the source of matter-energy, local creation of matter and small Big Bangs can occur anywhere where Quantum Fields (structures to create matter-energy -particles) are created in DM.

 

[Lov_space&rockets]

Hey, I am new around here.. Can someone please explain what are we supposed to do here? I've been on Quora before, so is it something similar to that where you answer people's questions?

 

[space_fanaboutaliens]

in the reply box sweets (i call ppl that in a friend-ish way even tho i dont know them)

 

[Wolfshadw]

Hey, I am new around here.. Can someone please explain what are we supposed to do here? I've been on Quora before, so is it something similar to that where you answer people's questions?

Yup!

If you have questions, feel free to ask. If you have answers, feel free to answer questions. Just be sure to follow the forum rules.

Wolfshadw
Moderator

 

[Lov_space&rockets]

K thanks for the info

 

[Catastrophe]

The original question was
How far can we travel through space, until the constellations are no longer recognizable?

Here is an answer to:
(11) How far would you have to go for the constellations to appear different? - Quora

QUOTE
The apparent location of stars within the field of view of an observer traveling through interstellar space would change with distance as the traveler got further and further from earth. The constellations, as we have defined them are, are made up of objects in vastly different positions in three dimensional space. Some are comparably close to us and others are extremely far away within a single constellation. The shape of a constellation would change depending on which one you were looking at.

Alpha Centauri is the closest star to us (it is actually a binary star) and is part of the constellation Centaurus. Traveling anything close to 4 light years tangentially to that constellation would alter the appearance of centaurus very quickly

There is a free program that will allow you to look at the stars from 'any' position in space and, therefore, see exactly how constellations change for yourself.
QUOTE

This is from the Richard Adkins reference above.

Cat

 

[Rathgic]

How far can we travel through space, until the constellations are no longer recognizable?

The reply to the reply COMPLETELY MISSED THE POINT OF THE QUESTION, I THINK.

There is no constellation relationship BETWEEN THEM, that has anything to do with HOW WE SEE THEM IN RELATIONSHIP TO EACH OTHER.

The stars making up a group we linked together, may well be so far apart, that a space traveler travelling around the world WOULD HAVE NO REASON TO ASSOCATION ANY OF THE STARS WITH EACH OTHER.

And I'm sorry, you're mistake, as I see it ;points out a very very important lack of appropriateness, in how we devote GROUP RESOURCES ie: taxpayers to matters beyond, the obviously very necessary problems associated with sending "information satellites and communication satellites into orbit.

An individual, of course may well find some interest in something that has no general relevance to solving problems we "may have related to being located on earth".

But, I suggest, "musing" of what we think "vague shapes light years away, that may themselves be light years apart and having no particular relationship to others, ie: as space travelers may see them FROM A VARIETY OF ANGLES.

Astronomers find relevance, in spending tax dollars to pursue their "personal interest in things they "see" relate to something simply because the are sideways close to each other.

Which is meaningless in terms of knowledge. I submit knowledge finds its basis in "reality" that is 100% consistent, in its defining characteristics. And it is these IN FACT PERMANENT RELATIONSHIPS..... NOT POINT OF VIEW RELATIONSHIPS, otherwise known as "personal opinions" based on ones own Narrow observations, along side of our unawareness, almost always, which by definition of being unaware, we haven't taken into account.

This is the ignorance and observed constant disagreement and inability of members of our government to WORK TOGETHER TO FIND WORKABLE SOLUTIONS.

It is, I suggest, the only way to become aware of what you are unaware of. And to take the position, THEY ALL DO, I have all the right answers, and anyone that disagrees with me, is to be treated as ignorant and ignored is arrogant.....the definition of which is assuming you have power and/or abilities you don't have.

And saying It "might be" (which implies it might not be, because of my inherent unawareness of what I am unaware of!!!!) is not grounds to spend taxpayer payer money. Why? limited government is limited to that which can be articulated and UNDERSTOOD, IN a rational thought process verification... we all share in common, because of knowledge......ie: patterns that we all should be able to see the same way, because they in fact do permanently exist!

And when you give limited powers, it only makes sense if you rationally can determine whether or not an act is within the limitations all workable governments must have. I suggest, that is what defines the difference between workable governments, long term and Dictators, which over and over prove themselves to be short term phenomenon!

If I am right that you n fact missed the point, to me it becomes important to know why you did so. I am sure you must be quite capable of not missing that point at least.

And we should expect the same of our politicians, and not elect and only have the choice to chose between those that profess to have all the answers AND anyone who disagrees is of no value. What works is called, I believe true humility. I need you to help me, always.

 

[Catastrophe]

It is completely correct to point out that everything to do with constellations or asterisms is based on line of sight. This changes depending on the distance from the observer.

Try this. Place your forefinger in front of and touching your nose. Now look through each eye separately. You will see a vastly different view. Now move your forefinger away to arms length and do the same. Little difference. Now apply this to a star in a constellation. Near objects will appear to change position greatly and distant ones very little.
Constellations may have (and usually don't) little connection between component stars. They only appear connected by line of sight.

Cat

 

[trisaddams]

Would anyone like to share with me their thoughts on black holes. Especially Sagittarius A* ......I'm completely infatuated with this black hole and how it has evolved.

 

[Catastrophe]

Hi trisaddams, and welcome to the forum.

I am particularly interested in t = 0. By that I mean that I separate BBT (Big Bang Theory) from the occurrence "before" science is able to address the BBT. Science cannot address a situation where you have division by zero, which is where you are before BBT is based on science.

I think it is wrong, and very confusing, to lump together the part science can address (BBT) with the metaphysical part which science cannot address (because the mathematics it is using ceases to apply to reality at t = 0).

So what has this to do with your interest in BH? Well, I am interested in the possibility (total speculation) that there is no such thing as a singularity (at t = 0) but a nexus which "leads backwards) into, guess what?, a black hole. So the idea is that a contracting phase of the Universe leads into a nexus (narrow, but not infinitely small) which is the black hole, and then it expands again via a big bang.

However, we are getting off topic here, so we must discuss the matter somewhere else - like a thread on black holes, Sit still a moment, and I will show you where.

Cat

 

[Catastrophe]

trisaddams, goto the search function and enter 'black holes' - and tick the box so we get just the thread titles. You will find three recent discussions. Choose the one which best suits your interest, and repeat your question there, and you can have an appropriate discussion.

Cat

This is what your search should show:

Search results for query: black holes

forums.space.com

These threads should really all have been started in the cosmology section. If you don't relate to the above threads you should start your own thread, but make sure you are in the cosmology section when you start your own thread.

If you were in the first option, which is in Cosmology, click on the Post Thread button, (It is on the right, and down a little) and you will get this:

Post thread

forums.space.com

Give the thread a title and type in the box below. Easy

Actually there is another thread you might consider, and it is already in cosmology:

Could This Be True? | Space.com Forums

 

[Classical Motion]

I don't know how far one would have to travel. But I do know the correct direction. Move sideways. A star group has an irregular shape. If you move toward it, only the size changes, not the shape. But if you move sideways, the shape will change quickly.

 

[Catastrophe]

only the size changes, not the shape

I disagree. Don't forget, you are considering line of sight phenomena. As you move in the direction of the group, distant stars will be little affected. Closer LOS stars will quickly move off towards the 'sides' so the shape will change drastically.

If you have stars closely connected within a group (not just a line of sight connection) then the shape will not change much until you are close enough to the 'real' group, that 'local' differences in proximity begin to produce the 'LOS' effect..

Cat

 

[Classical Motion]

It's not only that.....when were the stars there? We see them together now, but how long have they been together. Were they even there at the same time? Do you believe that the distant stars were there, at the same time the close ones were?

Speculation is all that one can do with stars. A collection of time stamps. An illusion. What you see in the night sky is not there. It's a collection of past theres.

And with any forward or backward displacement, that change would be much less than an angular change.

I disagree with your disagreement.

 

[Catastrophe]

How does your 'disagreement' apply to REAL groups in REAL proximity in a REAL co-similar time frame?

Cat

 

[Classical Motion]

I'm not quite sure what you mean. Do you mean taking the same pattern, and putting that arrangement on earth, so that all the all the light sources.....are in the same region at the same time?

Is that what you mean?

 

[Catastrophe]

What I am referring to, is that there are real star "clusters", which are groups of stars which are (relatively) close together, and not line of sight phenomena.

Cat

 

[Classical Motion]

Is it the stars that cluster......or only the starlight that clusters? When man sees a group of objects on earth, the objects have the same time. All of the objects are in their positions with the same time.

Trying to apply that discernment to the stars is a false discernment. Because the objects are not there at the same time. Only their light is. A star field is an illusion. That's why you need "spacetime" to explain it.

Any non spherical pattern, should change shape quicker with a change in angle, than a change in distance.

Edit: A sphere is a stealth shape.

 

[Catastrophe]

I disagree.

This is my final comment.

What I am referring to, is that there are real star "clusters", which are groups of stars which are (relatively) close together, and not line of sight phenomena.

Cat

 

[Pogo]

If you’re in an airplane in a large squadron of airplanes and they are all around you, somewhat randomly, all going generally the same direction and speed, but not exactly, the far away ones will appear to be between the closer ones, but smaller. You could mentally pick out shapes , triangles, rectangles, etc. comprised of these planes as the vertexes of these shapes. Move in any direction and the shapes change, or you see new shapes. Even if you maintain an even speed, they may change because the others are in relative motion to you. That’s kinda how the stars in the galaxy move, the constellations are just figments of our imagination that mostly the ancient Greeks named for convenience. The stars don’t care that we did that.

Rather than trying to travel by spacecraft because we still can’t go very fast in relation to the stars, just sit tight and stay alive for a few hundred millennia. The Solar System is moving about 220 km per second toward the figment of the imagination we call Hercules. The constellations will change over time because our our motion, especially the ones to our left and right.

 

[billslugg]

I understand that we are travelling relative to CMBR.
But I read that there is no absolute velocity in the universe.
Velocity is only relative, thus "Relativity".
And I read that no moving observer using any machine they carry with them can determine their own absolute velocity.
So what gives? Any ideas?

 

[Atilla De Bum]

How far can we travel through space, until the constellations are no longer recognizable?

About 10% of the diameter of the Milky Way, 100 light years or so. Parallax error will render most of the constellations unrecognizable.

 

[Atilla De Bum]

I understand that we are travelling relative to CMBR.
But I read that there is no absolute velocity in the universe.
Velocity is only relative, thus "Relativity".
And I read that no moving observer using any machine they carry with them can determine their own absolute velocity.
So what gives? Any ideas?

Assume you are on a space ship from galaxy A, traveling at 99% light speed. Galaxy B has launched a similar ship that will pass you in one week, also traveling at 99% Light speed. As an observer on Ship A. how fast the the Ship B traveling, relative to you. You have a week to prepare your observation equipment.

My physics professor said that such a speed of each ship would accumulate near infinite Mass (and Gravity) and so would Ship B. Therefore, the infinite Gravity's created by both ships would Attract each other and lead to a 'super nova', so the law of Light speed would not be broken, even relatively. I don't buy it.