New answers tagged distances
3
Supplementary to @uhoh's answer:
According to the wikipedia page he links, the most distant imaged object is a galaxy classed GN-z11.
GN-z11 is a high-redshift galaxy found in the constellation Ursa Major. The discovery was published in a paper headed by P.A. Oesch and Gabriel Brammer (Cosmic Dawn Center). GN-z11 is currently the oldest and most distant ...
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Distance in astronomy is equivalent to looking back in time, because of the finite speed of light.
If it's an object you're interested in, then Which galaxy is receding from the Milky Way the fastest? What is known of the mechanism behind its recession? covers it. There are various high redshift objects around $z=11$ which are being seen a few hundred ...
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This is a really interesting question to many and it deserves an answer post even if folks close it.
In Wikipedia's List of the most distant astronomical objects we can see that the distances that the light travelled to get to us are all around 13 giga light years, and it's no coincidence that the age of the universe is also about 13 billion years.
We can't ...
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We know, precisely, the ratio between the Earth-Venus and Venus-Sun distances. Kepler's laws give us this.
We know, in terms of apparent size in the sky, the precise size of the Sun in degrees - just by looking at it.
Placing Venus between the Sun and the Earth, we can look at it from one point in the Earth (call it $N$) and see Venus against the Sun at a ...
3
From Wikipedia
In his 1698 book, Cosmotheoros, Christiaan Huygens estimated the distance to Sirius at 27664 times the distance from the Earth to the Sun (about 0.437 light years, translating to a parallax of roughly 7.5 arcseconds).
and
It was also in this book that Huygens published his method for estimating stellar distances. He made a series of smaller ...
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Henrietta Swan Levitt was the first person to develop the "standard candle" technique for measuring the distance to stars, while studying Cepheid variables around 1912-1913.
Of course, the standard candle technique just extends the parallax technique to farther distances; in order to figure out how bright Cepheid variables are, Levitt had to know ...
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As far as I know direct parallax measurements are the only way to directly measure the distances to stars.
Once parallaxs of hundreds of stars were known and diagrams of the relationship between stellar luminosity and spectral types, such as the Hertzsrpung-Russel diagram, were made, it became possible to estimate a star's absolute magnitude more or less ...
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The CMB exists throughout the universe, but the part of the CMB we can measure is a distance of 0 meters from our telescope at the time of observation.
How far did the CMB travel before it got here? About 13.4b light years, since it was emitted approximately that long ago: wikipedia bibliography reference. Of course some small part of that radiation was ...
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The distance is that reported by Bihain et al. (2013), which is based on a mean relationship between absolute magnitude and spectral type that has a lot of scatter.
i.e. in contrast to most (all?) the other objects in that list, there is no reported trigonometric parallax measurement for this very faint T7.5 brown dwarf.
In fact, if it turned out to be a ...
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To find the distance from one star to another, we need three things for both of the stars: their right ascensions, declinations, and the distance from Earth to those stars.
So, let's get those things:
From the Wikipedia page on Alpha Centauri:
$RA = 14^h\:39^m\:36.49400^s$
$DEC = -60^{\circ}\:50'\:0.23737''$
$R = 4.37\:\rm{ly}$ (you gave 4.366, some other ...
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