Questions tagged [astronomy]
The science dealing with objects and phenomena located beyond Earth. In particular, this applies to observations and data. At its core, astronomy is the physically informed cataloging and classifying of the contents of the universe in order to better understand what is out there.
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$1°$ shift in sun's sidereal position over a day
I couldn't understand the bold lines in the following excerpt (from the book "Astronomy - Principles and Practice 4th ed. - A. Roy, D. Clarke")
The month is the next period of any ...
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Determining star position and velocity to deduce closest approach?
I am trying to replicate the results found for Gliese 710's closest approach of ~0.05 parsecs in 1.3 million years approximately. I thought that by plotting the sun at (0,0) and using the stars ra,dec,...
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$30°$ shift in a star position w.r.t earth over a month
I couldn't understand the following excerpt (from the book "Astronomy - Principles and Practice 4th ed. - A. Roy, D. Clarke")
The month is the next period of any significance to our watcher....
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Measuring distances between the stars
If we know how far away are the two known stars from Earth, then is it a safe bet that we can know how far apart those two stars are from each other using sine rules? Does that mean we must first ...
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(Astrophysics) How to calculate photons detected by a radiometer over a period of 10 seconds?
I know the Flux (calculated from flux density), and frequency but i dont think I have area.
This is the question, it is part d and ive done all other parts:
"Consider three widely separated ...
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How is the trajectory of a star found relative to the Sun?
So i know we can get radial velocity by measuring blue shift and then we can use the distance to the star and its proper motion to get its tangential velocity. In the case of Bernards star, its ...
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Determine the equation of earth's orbit
I am trying to find the the equation earth's orbit using Kepler's Scheme. After every 1.88 years Mars returns to its initial position in the sky.
With reference to the diagram and data below find the ...
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Is there a galactic "goldilocks" region in the galaxy
I'm wondering if there's a region where the star density in the galaxy create the conditions in outer space where the galactic temperature is between 0 and 200°F. This may cause a ring shaped where ...
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Estimate Saturn's mass [closed]
How can you estimate Saturn's mass using data from Cassini's final moments in September 2017 (apoapsis on September 12 at 1:27 a.m. EDT Saturn time at a distance of about $1.3*10^6$ km from Saturn, ...
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Einstein's derivation of stellar aberration formula: replacing the direction of the ray with a difference in angles justified?
I was going through the translation of Einstein's 1905 paper "On the Electrodynamics of Moving Bodies"(See https://einsteinpapers.press.princeton.edu/vol2-trans/175). In deriving the stellar ...
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Do the colder and warmer poles of the CMB's Axis of Evil corresponds to the terrestrial poles?
Does the terrestrial North or South Pole correspond to the colder and warmer poles in the CMB, as differentiated by the 'axis of evil'? If so, which to which?
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Observing an event horizon while approaching one
A thought crossed my mind that I realized was hard to conceptualize so I decided to simplify the question by putting it in terms of event horizons.
If I am an observer approaching black hole "A&...
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Is there any tools for observing magnetic fields and forces of black holes and galaxies?
I want to know about how we can find magnetic forces and fields in space around stars, planets, galaxies, pulsars especially pulsars. How (by what means) did determine magnetic fields around a pulsar?
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Is cosmological redshift associated with recession velocity when the light left or when it arrived?
Is the cosmological redshift $z$ associated with the recession velocity when the light left, when it arrived, or something in-between?
user300520
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Why is $G*M_{sun}=4\pi^2$ when using AU/year units?
So, when using AU/year units, it turns out that 3rd Kepler Law: $\frac{r^3}{T^2}=\frac{G*M_{sun}}{4\pi^2}=1$, meaning $G*M_{sun}=4\pi^2$, any easy explanation for this? Cheers.
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