Questions tagged [parallax]
Questions about the apparent displacement of a celestial body with respect to its background when observed along two different lines of sight.
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How to calculate moon's distance and parallax in it's altitude
I'm trying to calculate moon's parallax in it's altitude depending on the day I need and I followed this formula by geoastro.de Basics of Positional Astronomy and Ephemerides
but I need to calculate ...
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Calculating lunar parallax based on a distance between two objects at certain latitude
I want to compute lunar parallax based on the distance between two points. In fact I know the formula, but I guess they're explained wrong.
By looking at the image below we can see the polar radius, ...
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Betelgeuse, placing light bulb so that its apparent brightness is similar to that of Betelgeuse; wavelength where it shines brightest?
The giant star Betelgeuse will develop into a supernova in the future. After this event, his remains will be far too dark to be observed from Earth. In order to maintain the view of the starry sky, it ...
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How is parallax really measured?
I understand the basics of how parallax is measured (i.e. two measurements 6 months apart), but I also understand that, in reality, it would have to be more complicated than that, because stellar ...
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Why don't we use the Voyager/Pioneer etc space probes to measure stellar parallax?
With Earth based telescopes you get a max distance of 2 au between measurements.
While we have multiple space probes well over 100 AU away from us, that's a 2 OoM difference.
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What's the relation between the parallax distance and the luminosity distance?
I have read that Riess and his team are able to measure $H_0$ from supernovae calibrated using Cepheid in a model independent way.
from what I have gathered they find the absolute luminosity of ...
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What is the correct way to represent the Parallax angle?
I was recently reading about the parallax effect and hence had a doubt about the parallax angle.
A lot of places mention the parallax angle as (θ1 + θ2)/2 while in ...
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Determining the distance to the Moon from parallax using the following information
How could I determine the distance from the Earth to the moon by using the method of simultaneous parallax? I know the right ascension and declination as seen from two different points on earth. I ...
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Does stellar parallax only occur parallel to the ecliptic?
Does stellar parallax only occur parallel to the ecliptic, or has it been observed in other directions, too?
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How can I estimate a stars surface temperature, luminosity, radius, and lifetime only knowing it's solar mass and peak wavelength? [duplicate]
For example: if a 10 solar mass star emits light at a peak wavelength of λ = 300nm.
How can I calculate a stars surface temperature, luminosity, radius, and lifetime with this infomation?
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What is Mercury and Venus’ apparent retrograde motion?
I was having a discussion about Mercury being in retrograde, and I had explained it as Earth moving faster tangentially than Mercury so it looks like it’s moving backwards when we compare it with the ...
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Units in distance parallax relation
Relation between distance d and paralax plx is:
$$d (pc) = 1 / plx(arc)$$
When I want to express plx in mas, will it be
$$d (pc) = 1/[plx(mas)*1000]$$
or
$$d (pc) = 1000/plx(mas)$$
Thank you very much
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Measuring distance to stars - How to get parallax angle
This may be a bit of a noob question, but I am wondering how exactly to get the parallax angle in degrees when looking at a nearby star relative to background stars.
I have found the information ...
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Does the presence of dark matter in the Milky Way significantly distort our parallax based measurements of distance?
According to accepted astronomical wisdom, dark matter represents a large fraction of the total mass of the Milky Way. And thanks to Papa Einstein, we know that light rays can be bent when passing ...
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vertical shift is equals to half of angular dimension plus parallax plus atmosphere refraction
I'm developing a C++ computer library with the formulas in the book "Practical Astronomy with your Calculator or Spreadsheet 4th Edition" but I have a problem with the formula 49, "...
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