so many questions, so little time!!

[poider]

Hi I am new to the forum and am not an overly intelligent individual, so I hope I don't bore you all with my mundane questions, I have so many but will try to keep them interesting...

We know how fast light travels and we use that to determine the distance of the moon through reflectors and lasers etc,

How do we determine the distance of Jupiter or the Andromeda Galaxy or Kepler 186F?

Peter

 

[poider]

is my question that simplistic that 19 viewers do not bother to answer? or is the answer so complicated that readers are still typing their replies?

Peter

[BearOfNH]

Well, Jupiter is pretty easy. Astrologers have expended great amounts of effort in calculating planetary orbits, so we can tell you how far it is to any planet at any time.

 

For more distant objects one can calculate the location in polar coordinates on July 1, and again on January 1. This gives you a triangle with base 2AU=186,000,000 miles. You then use trigonometry to calculate the length of the other sides and >POOF< there you are.

[swansont]

is my question that simplistic that 19 viewers do not bother to answer? or is the answer so complicated that readers are still typing their replies?

Peter

 

To be fair, your title is not descriptive and requires people to view to get an idea of the question, so they would not know if they had the expertise to answer the question when they clicked on it. Also, some of those viewers are probably bots.

 

The method BearOfNH describes for the more distant objects is called parallax. For objects far enough away that parallax doesn't work, Cepheid variables (stars whose brightness periodically varies) can be used: there are two types, but for both their intrinsic brightness (i.e. the brightness a set distance from the star) is a function of the period. Since light drops off with the square of the distance, the ratio of the intrinsic brightness to their apparent brightness (what we see here on earth) gives you the distance.

 

There are other stars that are called standard candles because their intrinsic brightness is known, so the same calculation can be used.

 

http://www.atnf.csiro.au/outreach/education/senior/astrophysics/variable_cepheids.html

[poider]

so the 186,000,000 miles I Assume is the extremities of the Earths orbit around the Sun, but I cannot comprehend how we know how far from the Sun we are if we have no solid point of reference to compare?

Peter

I am not doubting anything that you tell me I just need it explained to me in simplest of terms, I guess without specific solid physical proof I find it all hard to follow, I am not the most mathematically minded person so any thing proven only by mathematics is hard for me to comprehend.

Peter

[Greg H.]

A lot of what goes on in Astronomy and Cosmology (and in physics in general) is supported by matematical models - we use those models to make predictions that we can test. Without the math, physics is just a bunch of interesting stories that may (or may not) actually relate to how the universe really behaves.

 

That math is what tells us what the orbit of the earth looked like before we could send a spacecraft out of the orbital plane of the solar system to actually look at it. It lets us land spacecraft on the Moon and Mars, put them into orbit around places ever further away, and tells us about places that no one living today will ever see.

 

Math is one of the most powerful tools the human race possesses and the best thing about it - it never lies. It may be misapplied, or the results may be misinterpreted, but those are failings in the humans using it, not in the math. If you're going to trust nothing else, trust the math.

[swansont]

so the 186,000,000 miles I Assume is the extremities of the Earths orbit around the Sun, but I cannot comprehend how we know how far from the Sun we are if we have no solid point of reference to compare?

Peter

I am not doubting anything that you tell me I just need it explained to me in simplest of terms, I guess without specific solid physical proof I find it all hard to follow, I am not the most mathematically minded person so any thing proven only by mathematics is hard for me to comprehend.

Peter

 

That was first addressed by observing the transit of Venus

 

http://brightstartutors.com/blog/2012/the-transit-of-venus/

[poider]

Ok so I am 49 yo I love Astronomy, Aviation and Photography, I like to combine those interests as much as possible, But I also work 5 days a week so cannot devote nearly enough time to any or all of them.

I want to learn more about the Mathematics but do understand that it is a huge undertaking at my age.

What books would you recommend that I get hold of for a beginner in the field of mathematics?

Peter

[K Sky]

Ok so I am 49 yo I love Astronomy, Aviation and Photography, I like to combine those interests as much as possible, But I also work 5 days a week so cannot devote nearly enough time to any or all of them.

I want to learn more about the Mathematics but do understand that it is a huge undertaking at my age.

What books would you recommend that I get hold of for a beginner in the field of mathematics?

Peter

 

Well, you can buy used or last edition academic texts online at Amazon for ridiculously affordable prices. Probably, start with Introductory Algebra or Intermediate Algebra, then College Algebra. Skip the trigonometry book because most likely the text after College Algebra, Pre-Calculus, will cover trig. Then it goes Calculus One, Two, and Three. It sounds like you might want to study some physics, in which you need to get through calculus one before a college level physics text can be managed. You can buy algebra based physics books, but you will have to skip a buncha steps. Instructors that teach algebra based 100 level physics courses, as opposed to 200 level calculus based physics courses, have to practically sell their students that the ensuing answer is on the horizon and such. By that time you will see the other maths like differential equations or whatever.

 

However, and I get your forty-nine and wise, but all that gets done outside of an academic environment as often as...(insert your cliche here).

[EdEarl]

Ok so I am 49 yo I love Astronomy, Aviation and Photography, I like to combine those interests as much as possible, But I also work 5 days a week so cannot devote nearly enough time to any or all of them.

I want to learn more about the Mathematics but do understand that it is a huge undertaking at my age.

What books would you recommend that I get hold of for a beginner in the field of mathematics?

Peter

khanacademy.org is a very good place to learn math. Its lessons begin with 1+1 and progress through calculus. There are short videos, and on-line practice. You can start with any lesson, and jump around if you wish.

[Airbrush]

"so many questions, so little time??"

 

Next time use a DESCRIPTIVE title so we know what this is about, and everyone can refer to it easily, such as: "How are astronomical distances determined?" Or simply "Astronomical Distances".

 

That has to be among the weakest topic titles I have ever seen. It is uninteresting and it puts everyone off. It sounds like you have a lot of questions and you want people here to hurry up and answer your questions because you don't have time?

 

Hurry up folks, I need service NOW!