Astronomy/Astrophysics

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Expert: Jesse Martinez - 2/27/2010


Question
How is it .... that........ no-matter which direction I choose to view the sky ( even opposite of where I just looked)....I can see back in time the same distance/length ? How can the sum of the two OPPOSITE directions (OP1 plus OP2) be Greater than the given age of the Universe?

Answer
Hello Carter. Thanks for letting me help you. Here is the answer in two parts.

Basic Answer:
There is a problem with the equation. If OP1 and OP2 are distances, the sum cannot be a unit of time. You may be able to see trillions miles in one direction and trillions in another, but adding the two yields another distance. Since the age of the universe is not a distance, the equation is not valid. It is a bit confusing, but there is an explanation for what I believe you were getting at.

Advanced Answer:
It was explained by several people, most notably Albert Einstein. It is called relativity. At typical earthbound human distances and times like meters and minutes, it is not even thought about, because it matters little or nothing. At stellar distances, you are right. You are looking back in time no matter what direction you look in. However there is not a paradox in that fact. All light and radiation travels at the speed of 186,000 miles per second. So if something is a light year away, the light we see left the object a year ago. The important point here in your case, is that we do not know if the object still exists. In fact, a lot of the objects in deep sky no longer exist.

Let me know if you still need more info. If I did not address the question to your understanding or needs, let me know with a follow up. I am always glad to help.  

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Jesse Martinez

Expertise

General and specific questions about the solar system and stellar and galactic astronomy, are what I can easily answer off the top of my head. For example, what is the largest planet in the solar system? How far away is the moon? Have there been any confirmed planets in orbit around stars other than the sun? How many stars are there? The tougher ones like explaining the big bang theory and black holes I will leave to the PhD’s. Even though I could muster an answer, I would have to research it more than I would like. I would also like to answer questions that involve Astronomy with other sciences, chemistry, biology, physics, geology and mathematics as long as they are not PhD level.

Experience

I have been into astronomy since I was 8 years old. I have kept detailed journals of my observations through small telescopes. Over the years I have participated in amateur observation projects for organizations like ALPO. My personal research has involved "discovering" the moons of Jupiter with a 4½-inch Newtonian reflector without any outside information like charts and tables. In a summer long project, I determined the existence of and plotted the orbits of the four major moons of Jupiter. From these observations, my data on orbital elements was surprisingly accurate (orbital radius and orbital period).

Education/Credentials
80 hours of college credits while studying physics and geophysics. Completed correspondence photography course while in high school. Took two semesters of electronics training at a community college. Studied computers and graduated from a technical school at the turn of the millennium, gaining A+ and Microsoft Certified Professional credentials. Hablo Español. Si quieres preguntar en Español, estoy a su servicio.

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