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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Do stars of higher metallicity have more planets in highly-inclined Pluto-like orbits?
In an answer to a previous question of mine, one that asked about the planar orbits of inner planets, I was told the following (emphasis mine):
On the subject of different solar systems, I would ...
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57 views
How to identify the objects in an astrophoto, and what portion of the sky it covers?
Given an astrophoto with a resolution between 0.5 and 5 arcseconds per pixel, which ways exist to identify the direction of view, field of view, and objects in the picture?
I believe most amateur ...
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Could asteroseismology have a significant potential to unravel the mechanisms of solar cycles that last thousands of years?
Could asteroseismology have a significant potential to unravel the mechanisms of solar cycles that last thousands of years?
And what about solar cycles 1 billion years ago and 2 billion years ago ...
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Did I see two Milky Ways next to each other?
I am from the northern hemisphere and as far as I remember, the Milky Way was "single lane", just one stripe. At least, this is what I recall the Milky Way to look like when seeing it from near ...
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Are the inner planets on planar orbits because there was more dust in the inner solar system (early on in planetary accretion)?
Question inspired by a question thread here.
So when there's lots of dust in a galaxy, the galaxy tends to collapse into a spiral galaxy (to maintain angular momentum and to minimize gravitational ...
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Mirrors and light beam divergence technology limits
There are many applications for orbital space mirrors in astronomy (better telescopes) and space propulsion (solar power for deep space probes), but this is limited by the minimum beam divergence ...
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Where does a star's angular momentum go as its spin slows down?
So we know that stars slow down as they age. But total angular momentum must be conserved. Where does that angular momentum go?
The dissipation of Earth's tides somehow transfers Earth's angular ...
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Distribution of each element and molecule as a function of distance from the Sun and as a function of time
Are there any graphs that show the distribution of each element and molecule as a function of distance from the Sun?
And maybe even the time-evolution of each distribution over the solar system's ...
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267 views
At what temperature does water become a liquid on Mars? On the asteroids? And in a vacuum?
I know that I can just read off the phase diagram for water (for the surface atmospheric pressure on each object). But could there possibly be some nuances that someone might miss just from viewing ...
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How fast will the sun become a red giant?
I've read many accounts of our sun's distant fate, but what I've never heard is on what time scale these events occur.
For instance, when the sun runs out of hydrogen, I presume it doesn't just WHAM! ...
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Why is the mapped universe shaped like an hourglass?
I've watched a video from the American National History Museum entitled The Known Universe.
The video shows a continuous animation zooming out from earth to the entire known universe. It claims to ...
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Vesta dwarf planet status
Now that we have close-up photos of Vesta, which the IAU had previously said was a candidate dwarf planet, when is the IAU going to decide the issue? Personally, Vesta doesn't look round enough to me.
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Solar system, visible stars and deep sky objects
Since I've seen that galaxies are often called "deep sky objects", as opposed to individual stars, does this mean that all visible stars in the night sky actually only belong to The Milky Way Galaxy?
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81 views
Is there a map of the particles in outer space?
Since outer space is not quite a vacuum, and the distribution of various heavenly bodies is locally inhomogeneous, it seems reasonable to expect that the density and variety of particles ...
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402 views
Are we capable of discovering planets in the Andromeda galaxy?
I just watched this SpaceRip video on YouTube which shows pictures taken by Hubble while looking into the disk of the Andromeda galaxy to study a certain type of variable star. It occurred to me that ...
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157 views
What is the largest observed celestial body?
I'm not referring to phenomena such as galaxies or clusters but rather, what is the largest discrete celestial body that has been observed in the universe?
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Would it be interesting or useful to map objects' current (predicted) locations?
Due to light travel time, we observe astronomical objects as they were in the past. If we knew objects' motion (relative to us), it seems like we could extrapolate to their present positions, but I ...
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“Blue Bumper” Stars
I was recently overviewing various massive compact halo object studies (the Anglo-Australian MACHO collaboration and the French I/II EROS collaboration), and they frequently reference "blue bumper ...
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Which current big Earth-based telescopes are equipped with adaptive optics?
I know only that the VLT is equipped with adaptive optics (AO) to bypass atmospheric distortion. Is it the only one, or have other telescopes been build with AO in the optical and infrared spectrum?
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Was Sun a part of a binary system?
I've read that many stars and other celestial bodies are found to constitute binary systems where the two bodies spin around each other. But our Sun is one of the exceptions. Could it be possible that ...
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1answer
138 views
Relationship between Mars and Earth rotation
Is it by pure random chance that Mars and the Earth have nearly the same day duration (Mars day is barely 40 minutes longer, which is just 3% difference), or there is some causal relationship between ...
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The Moon during the day
Why do we see the Moon during the day only on certain days and not every day?
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1answer
791 views
How dense are nebulae?
How functionaly dense are nebulae? Are they so sparse they are only visible from an interstellar or intergalactic perspective or would you be unable to see your hand in one?
Do they vary widely in ...
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2answers
268 views
Why aren't gas planets and stars fuzzy?
The edge of Jupiter looks very sharp.
Even more bothersome, the edge of the sun looks sharp, aside from kind of a soup of particles floating above it.
The sun's surface has an incredibly low ...
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137 views
Why did the ancients fail to discover that the Earth orbits the Sun?
The ancients observed that the Sun and the 'fixed' stars rotated about the Earth. They were also aware that the Earth was spherical. They performed many astronomical measurements on the planets - ...
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173 views
Applying the Maxwell–Boltzmann statistics to astrophysical objects
Quoting Wikipedia:
In statistical mechanics, Maxwell–Boltzmann statistics describes the statistical distribution of material particles over various energy states in thermal equilibrium, when the ...
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609 views
View of the Sun from Voyager 1
Today Voyager 1 is approximately 122 AU distance from the Sun. What does the sun look like from this distance? How much brighter does the sun appear to the naked eye compared to other stars in the ...
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What examples are there of fuzzy concepts in astronomy?
What examples are there of fuzzy concepts in astronomy? In particular, how fuzzy are the boundaries between different types of stars?
As an example of a fuzzy concept I'm thinking of the planet/brown ...
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135 views
What are the easiest ways to get data out of a FITS file without a library?
There are FITS libraries for most programming languages (see this list), but FITS is a simple enough format that it should be pretty easy to extract data without the need for such libraries or ...
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Sillicon based life
My question may not be suitable here, because it's more of astrobiology. Life as we know, is carbon based.
Is it possible life based on silicon?
What will be the conditions for habitability for ...
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37 views
Why did the june 2011 lunar eclipse last so long?
It was kind of hard to miss the lunar eclipse this week, although I didn't see it in person (Sod's law means that on every relatively major astronomical event clouds cover where I am). From what I ...
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140 views
Could a planet ever end up with a doughnut hole in it?
If there was an asteroid that happened to be made out of something really solid (iron, titanium?) and it got enough velocity (sling shot around the sun?), is it conceivable that it could hit a planet ...
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Why is a new moon not the same as a solar eclipse?
Forgive the elementary nature of this question:
Because a new moon occurs when the moon is positioned between the earth and sun, doesn't this also mean that somewhere on the Earth, a solar eclipse ...
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185 views
Significance of letters in Hertzsprung-Russell (H-R) diagram
The Hertzsprung-Russell diagram that categorizes star types uses the letter codes O, B, A, F, G, K, and M to indicate a star's temperature/color. Hottest (blue) is O and coolest (red) is M.
What do ...
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Is a rogue 'exoplanet' classed as a exoplanet?
Given that the term planet strictly (according to the IAU) refers to a body around the sun, rogue planets can't be called that, so I assume they must be called rogue exoplanets?
But do they even ...
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Where to find Lunar Eclipse data
I am wondering whether there's a good resource to find data about upcoming Lunar Eclipses.
For example, showing the percentage of the eclipse over time. Such as: 17:23 GMT - 0%, 17:40 GMT - 10%, etc.
...
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What possible science could we do during the 2012 Venus transit? [closed]
I had previously asked about how useful everyday solar physics data is to other astronomers ... But about a year from now, we will have another Venus transit, where Venus will pass between the sun and ...
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Recommend good book(s) about the “scientific method” as it relates to astronomy/astrophysics?
I am interested in astronomy/astrophysics, but I am not science major (I am a computer science graduate). Facts and results of the field are presented to the public without showing how these ...
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How would the night sky appear at the edge of the galaxy?
In Isaac Asimov's Foundation Series, there is a planet named Terminus which is believed to be the planet farthest from the galactic center.
There are almost no visible stars in its sky, only the ...
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453 views
Does the Moon's core still contain significant heat?
On earth, using earth-sheltering techniques can significantly reduce the temperature fluctuations on a structure. Would the same statement be true as well on the Moon? Does the Moon's core still ...
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186 views
Where to find the current positions and velocities of the planets?
I've written a program which simulates the motions of planets and other bodies. I'd like to run it on our own solar system, but to do so I need to know the current positions (preferably in ...
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How far are constellations recognizable?
A novel of the 'Foundation' series mentioned that the universe being 3-D the shape of a constellation is recognizable only in the near vicinity of a given planet. In other words move out from the ...
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If there was no Earth, what would be the acceleration of gravity from here from the Sun?
Suppose there were no Earth to pull us back and we're hanging in the solar system. Assuming no other force of gravity from other bodies, what would be the $g$ from the Sun?
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What day/night cycles, climate and seasons would experience Alpha Centauri Bb inhabitants?
Alpha Centauri Bb is an exoplanet orbiting Alpha Centauri B. It is asserted that given the close distance to the star the planet should be tidally locked.
The orbiting period of the planet is about ...
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5answers
735 views
What do the colors in false color images represent?
Every kid who first looks into a telescope is shocked to see that everything's black and white. The pretty colors, like those in this picture of the Sleeping Beauty Galaxy (M64), are missing:
The ...
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530 views
Cameras in Voyager probes
I've always wondered about the cameras in the space probes, especially in the Voyagers.
1) What kind of cameras do they have? Digital? (What kind of sensor and megapixel count?) Analog? (Do they ...
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1answer
118 views
How many earth-sized planets have been discovered outside the solar system?
How many earth-sized planets have been discovered outside our solar system? Is there a combined registry of them anywhere? Where might I look for more information?
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Shapes of galaxies
I've heard most of galaxies are spiral or ellipsoid shaped. Is it true?
If true, then why they form in such shapes?
How did arms of the spiral galaxies form?
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How are newly discovered objects (stars, planets, galaxies…) named?
When a new astronomical object (star, planet, galaxy, comet, etc.) is discovered, what is the official procedure to name it? Who decides about the name of it? Can they be changed in time?
Extra ...
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What is the most distant object from the Earth that a spacecraft has visited to date?
What is the most distant object from the earth that a spacecraft visited has visited so far? What was the mission and when did it happen?
