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0 votes

Redshift distance proportionality at high Z and need for "mighty mouse" galaxies?

From a big bang theorist point of view it is assumed that the galaxies at higher redshift are indeed smaller then present day, close by, galaxies. This is believed to be explained by a merging process ...
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-1 votes

Seeing a galaxy (quasar) greater than 46.6 billion light years away

No that would be impossible. Even if we were to observe a galaxy that is basically infinitely redshifted it would not be interpreted as having its light sent out earlier than 13.72 billion years ago ...
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2 votes

How can I convert a galaxy arcmin to light years?

I am one of the editors of Wikipedia's "List of largest galaxies." We chose not to use the input from the "Basic Data", which gave an apparent diameter of 2.3 arcminutes. This is ...
2 votes

How can I convert a galaxy arcmin to light years?

A simple, non-scientific calcultor method is to multiply the angular size in radians by the distance. I get a different and much smaller value. ...
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3 votes

What is the difference between the Synodic & the Sidereal Periods?

If you think of the Sun, Earth, Moon system. The Earth orbits the Sun, and the Moon orbits the Earth. At a full moon, the bodies are essentially lined up, the synodic period is the average time to ...
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7 votes
Accepted

What is the difference between the Synodic & the Sidereal Periods?

A planet is in opposition when it is on the opposite side of the sky from the sun, so it will be due south at midnight. The synodic period is the (average) time between oppositions. Or, more generally,...
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5 votes

How exactly was Giovanni Cassini able to measure the distance to Mars?

This is my first post on Stack Exchange so bear with me, I'm new to this. I've been looking into the Cassini / Richter measurement for quite some time, and I think I have something to add here. Using ...
2 votes

Distance of distant galaxies

Redshift, angular-size distance, and time-since big bang are all ways of describing the distance of an object or (since distance and time are related) the time when the light was emitted. Now, you ...
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