1
vote
1answer
19 views

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 ...
9
votes
3answers
392 views

Statistically, what would the average distance of the closest black hole be?

The closest confirmed black hole is several thousand light years away from earth. Our galaxy has about 100 billion stars. I didn't find any reliable information on the black hole count of ratio versus ...
0
votes
1answer
10 views

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, ...
5
votes
3answers
269 views

Is extraterrestrial mining more difficult or impractical for bodies without plate tectonics?

This article talks about the possibility of mining Uranium on the moon. Since the Moon lacks the geological forces that have created veins of concentrated minerals on Earth, would extraterrestrial ...
0
votes
1answer
87 views

Blackhole Finding Techniques

I know of two methods for finding exoplanets: the transit method and the radial velocity method. These two methods work as follows: Transit: we observe stars and watch for when a planet obstructs ...
3
votes
1answer
105 views

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 ...
5
votes
3answers
308 views

What happens to the information on the event horizons of two merging black holes?

What happens to the hairiness/information on the horizons of two black holes if they collide? After Hawkin the information of the matter which has fallen into the blackhole is encoded on the surface ...
-1
votes
1answer
133 views

Cluster of fast moving stars

We live in NW Tasmania in a country town and tonight out walking I pointed out a long cluster of stars to my sister as they made an unusual shape but then we realised they were moving really fast - we ...
-1
votes
0answers
32 views

Bright two moving lights on the night sky [on hold]

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 ...
3
votes
1answer
33 views

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 ...
0
votes
2answers
24 views

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 ...
4
votes
3answers
50 views

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 ...
3
votes
2answers
152 views

Advancement of perihelion, data

I was looking for accurate and up-to-date data regarding the advancement of the perihelion of the planets in the Solar System, the only ones I've found so far are at least 90 years old bout I really ...
-2
votes
0answers
23 views

Planets, gem stones and their psychological effect on society [on hold]

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 ...
1
vote
1answer
57 views

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 ...
-4
votes
0answers
36 views

Why did the Big Dipper form? [on hold]

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 ...
3
votes
1answer
147 views

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 ...
3
votes
1answer
88 views

Universal point for sky observation

Is there a place on Earth, where polar axis lies on the horizont and heaven equator is in zenit? If it exists, can I, in theory, see all the constelations available worldwide this night?
1
vote
2answers
89 views

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?
3
votes
1answer
81 views

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 ...
6
votes
1answer
832 views

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 ...
2
votes
1answer
61 views

Astronomy Calculations Tool

I took many images like the following: As many of you may recognise, this is a picture of Jupiter and its four Galilean moons. Using these images, I am aiming to calculate the mass of Jupiter by ...
-1
votes
0answers
31 views

Stars in a straight line [on hold]

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 ...
4
votes
0answers
28 views

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 ...
2
votes
2answers
251 views

Why does the moon appear on cloudy night sky?

Now, I was looking the sky when I saw the Moon showing up in a sky completely cloudy, like this: But a little different. The clouds were doing an eye shape. What does explain that phenomenon? ...
5
votes
2answers
2k views

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 ...
1
vote
0answers
15 views

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 ...
0
votes
1answer
53 views

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 ...
-3
votes
0answers
34 views

New moon and full moon [on hold]

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?
0
votes
1answer
26 views

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 ...
6
votes
1answer
170 views

Why are Saturn bands much fainter than Jupiter's?

The atmospheric composition of both planets are very similar. Then why are Jupiter's bands more visible (North and South equatorial belt, etc.): Whilst Saturn's are not: (except for the storm of ...
0
votes
0answers
20 views

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 ...
3
votes
1answer
212 views

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 ...
1
vote
3answers
145 views

Calculate time when star is above altitude 30°

To find the best observation time for an object, I'd like to calculate the time when it is 30° or more above the horizon. Local Sideral Time would be sufficient. To include that in my program, I need ...
5
votes
1answer
155 views

How to calculate geocentric conjunction time and moon altitude at a given time

Umm al-Qura calendar of Saudi Arabia determine the new moon if these criteria meet at 29th day: The geocentric conjunction occurs before sunset. The moon sets after the sun. I've got the formula ...
1
vote
3answers
140 views

Do bigger telescopes equal better results?

There are many large reflecting/optical telescopes around the world, just to name a few: the Very Large Telescope, Large Zenith Telescope, and European Extremely Large Telescope. My question is does ...
4
votes
1answer
44 views

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 ...
6
votes
3answers
218 views
+50

Visibility of human activity on the moon

In this video the host of Test Tube Plus states that you can go out a buy a laser, point it at the moon, and see the retroreflector left by the astronauts. When you point at the right spot you'll ...
3
votes
1answer
246 views

Do stars start with rocky core?

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?
1
vote
1answer
76 views

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, ...
1
vote
1answer
53 views

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 ...
0
votes
0answers
16 views

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...) ...
0
votes
0answers
21 views

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 ...
1
vote
2answers
102 views

What is the effect of the axial precession on the orientation of the planet's orbits?

I am working on an online application to visualize the positions of the planets and to calculate their ephemerides (you find it here, but it is not complete yet). I do not have much knowledge in ...
0
votes
1answer
63 views

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 ...
7
votes
1answer
156 views

Have Pluto or any of its moons been mapped?

I was looking over some of the data for the terrestrial planets, and noticed that Venus, despite its cloud covering, had been mapped by the Arecibo Observatory. Also that other planets such as mars, ...
0
votes
0answers
21 views

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 ...
1
vote
1answer
31 views

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)?
1
vote
1answer
21 views

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 ...
1
vote
1answer
262 views

Is there a simple, analytical formula for the lunar phase brightness curve?

Brightness of the lunar disk varies as a function of phase angle. This phenomenon is very well established, as is the increase in brightness at low phase angles. Is there a simple analytical formula ...

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