# All Questions

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### What is the origin of the dust near the sun?

In this question I asked about the Solar Probe Plus mission. Reading a 2008 report I saw that there is an elevated exposure to high velocity dust near the sun. I understand the high velocity, anything ...
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### Is the radius used in the formula for the escape velocity the average radius of the celestial object or the radius at the starting location?

I learnt that the escape velocity is given by $$v_e = \sqrt{\frac{2GM}{r}}$$ Say I want to launch a rocket from the earth into space and want to calculate the escape velocity $v_e$ (I guess without ...
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### Why does the Moon appear gray when passing between the Sun and the Earth?

Shouldn't the Moon appear as bright as a full Moon seen at midnight from Earth? The photo was taken by DSCOVR at Lagrange point 1. In the picture, The Moon appears dark gray. Of course the Earth ...
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### Refraction by Saturn's atmosphere - how dense is it here?

This tweet from CassiniSaturn shows an image of Saturn's rings being optically distorted by the dense atmosphere. It is explained more fully on this page and is available here. The refraction is ...
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### Can't find cassiopias SCHEDAR or CAPH in Tycho-2 catalog supplement 1

So I'm trying to locate three stars inside Cassiopeia, gam cas, schedar, and Caph. I have found gam cas inside the tycho-2 catalog supp1.dat file, however when I look for schedar or caph I have no ...
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### Is the sun really white? [on hold]

"If you could travel into space and look at the Sun without going blind, you'd find that it's actually white, and not yellow" "White light is composed of all the visible colors in the electromagnetic ...
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### Weird light in the sky, curious as to what it is [on hold]

One night (a couple days ago) I looked out my bedroom window and saw a red light. It was fairly big but obviously not close to the window. It was moving, back and fourth between the distance of a ...
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### Parts of the Universe Shows Fewer Named Stars [duplicate]

I'm becoming interested in the currently identified stars in the universe. There is a wide swath where much fewer named stars are shown. Why is this? The image below is a mollweide projection of the ...
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### is this a real situation?

I found this picture and I am really wondering if it is possible for the moon to get as close to the earth as this picture shows? ( Super moon above Rio De Janeiro)
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### Current communication delay to mars [migrated]

I'm not sure if I should ask this question here or on the Space Exploration Stack Exchange. If I'm on the wrong network here, please let me know. I read that the communication delay between earth and ...
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### Using SkyChoord to read in multiple coordinates.

so I recently wrote a basic code to analyze the distance between two points which are stored in two separate excel files. Now that I have that code working its time to apply the legitimate use and use ...
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### Jupiter, Saturn, Uranus, Neptune system GM

I'm modelling the solar system. I'm using data from Nasa. To do this I'm using the barycenter of the planets Jupiter, Saturn, Uranus, Neptune. However the website fails to give the Gravitational ...
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### How far away is the nearest compact star remnant likely to be?

Neutron stars and black holes are hard to detect when they are solitary, and there seems to be big uncertainties about how common they are. White dwarfs are much easier to detect and the nearest one ...
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### More than 67 Jovian moons?

Wikipedia says that there are now 67 known moons of Jupiter. It got me wondering: is it really possible in our day and age that there are more, but we haven't observed them yet? On the other hand, ...
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### What is the temperature of the solar atmosphere (the corona) and how is it measured?

The temperature of the Sun's atmosphere, also referred to as the solar corona, is known to be hot even hotter than the Sun's surface. What is its temperature and how is it measured? How does it ...
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### Is remote measurement of isotope ratios possible, or must a sample be aquired

Is it possible to measure to measure isotopic abundance of remote astronomical objects - ie measurement without having a sample to feed into a mass spectrometer? Do different isotopes show any ...
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### Planets, gem stones and their psychological effect on society [closed]

I have been having a pretty bad events happen to me lately. Any new undertaking turns sour. Situations that seemed to be getting better yesterday suddenly take a turn for the worst. For example I ...
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### Bright two moving lights on the night sky [closed]

About a month ago, I was out with my friends, It was midnight, and We were watching a bright dot in the sky. It was shining more than the stars. (It is there everyday, cca. 3 years, before that it ...
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### Why did the Big Dipper form? [closed]

There is an asterism comprising 7 stars, known as Saptarishi mandalam, but better known to the Western world as the Big Dipper. It gets its name from the seven rishis. Why did this asterism form, why ...
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### Why celestial objects appear brighter in the night sky than in photographs from closer proximity?

The moon, for example, appears very bright in the night sky, but quite dark from photographs on/near its surface. Similarly, Mars and Venus appear as bright dots in the sky but in closer photographs ...
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### Is it possible that a star system ejects an object out of the galaxy?

I know it is possible that a star system ejects a planet out of the star system and the planets becomes rogue planets and orbit around the galaxy. Is it also possible that a planet gains enough speed ...
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### Interfacing FORTRAN programs for model atmospheres with IDL or Python

I'm trying to use model atmospheres such as Kurucz or MARCS for the first time personally and I'm wondering if it is better to wrap it with IDL or Python in terms of writing the code, and getting the ...
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### Stars in a straight line [closed]

I have observed many 2 stars which will be distant but seeing from here it will be in a straight line. Similarly 3 stars which is short distant to each other will be in a straight line. How is it ...
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### What is the projected range of the JWST to be able to detect exoplanet atmospheres?

Yesterday the K2 mission detected transit events of objects passing in front of a number of M dwarfs which could turn out to be rocky planets. If some of these planets host atmospheres, could the JWST ...
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### Can I get help getting image of Celestial Body at RA 2.220 and Declination +15.59?

My mom had a star named for my dad who died a few years back. I told her that I'd try to find an image of that star and send it to her. My dad's Birthday was 3/31/1931 if that helps. Would love ...
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### Galaxy centre X structure - could this reflect impact of black hole at galactic centre

As reported in this science article X Marks the spot Centre of Milky Way, a X shaped feature is confirmed centered on our galaxy's centre, when looking on from within the plane of the Milky Way. In ...
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### How far into intergalactic space would you have to go to see the Milky Way?

If in the distant future a ship were somehow able to move beyond the galaxy and into intergalactic space, how far would it have to go before we could look out a window and see the Milky Way in its ...
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### Do far away planets reflect light in the same way our moon/earth reflects light?

Here’s a scenario: Say you’re up in space and you’re far enough way that you can see the planet earth. Whilst looking down, you can see blue sky, blue water and green land and white clouds and ...
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### How often is a blue moon?

A blue moon is two full moons in the same month. How many times will a blue moon occur in the average lifetime of say 70 years?
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### New moon and full moon [closed]

When it is new moon we call it as amavasya . How does the moon grow and attain full moon. We call this as pournami. Again it is getting diminished. How does this happen?
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### How many stars would it take to draw a line across the middle of the sky that appeared solid?

I was talking with a friend about how slowly the star field changes (based on the speed that we are moving through the galaxy) and I started to wonder about a star's visible size. They are basically ...
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### Does Eddington's variable polytropic index better fit data from the Standard Solar Model?

I came across a 1938 paper by Arthur Eddington1 in which he discusses stellar polytropic models where the polytropic index $n$ varies inside the star, decreasing from a value $n_2$ at the surface to a ...
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### how can a supermassive black hole cause so much energy to enlighten its matter when its massive gravity prevents light to escape?

to cite this german newspaper: Das Materie-Monster sitzt den Angaben zufolge im Herzen der 42 Millionen Lichtjahre entfernten Polarring-Galaxie NGC 660, deren Aktivität innerhalb weniger Monate ...
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Is it true that stars start with a rocky core, then collect hydrogen by the gravity of that rocky core, just like planets collecting materials?
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### Where are the Moon rocks from Apollo? [closed]

There were so many Apollo Missions, and they landed on the moon (so they say). When astronauts came back to Earth from the moon, they brought Moon rock samples. Where are these moon rocks/samples now, ...
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### How much do gravitational waves distort space near a black hole? [duplicate]

This is something that I've been wondering for a while, but I don't have the math background or general relativity expertise to figure it out (and Google seems strangely lacking in this question...) ...
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### Which 16 antenna locations are used for the MeerKAT radio image recently announced?

The final configuration of the MeerKAT radio array will be 64 dishes. In the press release of July 16, 2016 a radio image is shown using a completed sub-set of 16 dishes. Which 16 are these? I can ...
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### Do far away stars that we observe today still exist?

I don't know much about the astronomy or the universe but enjoy reading articles from time to time as they pop up. Just finished reading an article on CNN that discussed how a South African telescope ...
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### Is There Any Center of Universe? [duplicate]

As it is said..the universe began from the big bang and since then it's been expanding. So the big bang would have happened at one point.. And all the matter is expanding around it.. So.. Is it ...
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### Could celestial coordinates be encoded into three-word combinations?

I came across this cool tool which encodes geographic coordinates into 3 dictionary words - table.lamp.chair - for example. You can see their map here https://map.what3words.com/. It divides the world ...
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### A question about the distribution of mass among the planets in the Solar System

Is it coïncidence that the mass of a planet has about its maximum in the middle planets (Jupiter), while the mass of the closest and furthest planets has a minimum (Mercury and Pluto)?
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### Energy carried by solar wind

What are the velocity, mass, and charge distribution of the solar wind. Near the earth within the magnetosphere in the ecliptic Near the earth but outside the magnetosphere in the ecliptic Outside ...
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### Do primary mirrors in large observatories undergo regular removal and re-coating of the aluminum? Why?

Performance of astronomical mirrors that are exposed to the environment for long periods of time can experience a slow degradation of performance. They usually need to receive some kind of regular ...
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### are nebulas reflections of earth emmitted images? [closed]

orion nebula has a horsehead image which I believe looks more like a partial spynx,, could the Egyptian spynx be constructed based on the human race that constructed curved polished rosemary granite ...
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### Why is the exoplanet HD 131399Ab so hot?

Recently, a fascinating triple-star system with an exoplanet has been discovered (arxiv). I'm very surprised about the temperature of the exoplanet: it is roughly 850 kelvin, even though its orbit ...
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### Why so many MPECs about TNOs lately?

The Minor Planet Center's electronic circulars for July 15 through July 18 reported an unusually high number of re-observations of known trans-Neptunian objects. These were found in the Pan-STARRS ...
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### Extraction of error spectrum in Sloan Digital Sky Survey

I need to know does SDSS spectrum contains error spectrum as well? http://www.sdss.org/dr12/spectro/spectro_basics/#AbouttheSpectra The above link says, further HDU's contain error spectrum and than ...
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### Can stars be seen in the background when looking directly at our solar system?

Imagine viewing the solar system from the outside: Considering the sun is quite bright, would you still be able to see stars in the background, or does the sunlight disable us to do so? Consider ...