0
votes
0answers
42 views

An anti-black-hole-engine

I'm just a fan of astronomy. Let's imagine humanity has limitless possibilities. How is it possible to create an anti-black-hole-engine? I mean everything inside reach of the engine can move inside ...
0
votes
1answer
85 views

Are galaxies moving away with constant acceleration?

Suppose that we could measure the current acceleration with respect to us of a distant galaxy chosen at random in our observable universe (Ignore the peculiar motion of the galaxy). Is the ...
1
vote
1answer
55 views

What's the significance of finding neon on lunar atmospehere? new explanation of moon light?

Now that NASA's LADEE spacecraft has confirmed the presence of Neon in the moon's atmosphere could the official explanation of the moon's light end up being change from reflecting the sun's light to ...
0
votes
0answers
14 views

Standard conditions for a heliacal rising

I imagine there are several possible conditions for determining the time of a helical rising of a star, the elevation of the star at sunrise, the latitude of the observer, and the azimuth of the star. ...
1
vote
2answers
52 views

Is it just the observable universe that is expanding?

Is it possible that it is just our observable part of the universe that is expanding, in the time that we exist, and other parts are both expanding and contracting at different rates and times? Would ...
0
votes
1answer
71 views

Did Big Bang sound as loud as we think?

As we all know, There is no sound in space, because sound waves don't travel in a vacuum. But even if Big Bang did sound, what was the main source of it's cause?
1
vote
1answer
49 views

Looking for planetary position calculation

In Hindu astrology, for creating horoscopes (birth charts), I am looking for calculations of planetary positions. So, how could I calculate planetary positions according to given date, time and place? ...
1
vote
1answer
33 views

What is the mass limit in a stellar accretion disc?

I became curious about the maximum mass in a star's accretion disc while watching an episode of Star Trek involving a Dyson Sphere. I wondered if some maximum amount of stellar material would limit ...
1
vote
2answers
66 views

How does 'centre of mass' concept work?

We know that two celestial bodies rotate around a center of mass. How does this concept work in case of solar systems where there are several planets versus one/two stars? (Even if the center of mass ...
4
votes
1answer
61 views

What's the distribution curve for meteor sightings?

I know that meteor showers have a "peak" observation time. What does the distribution in time look like? Is one side of the peak steeper/shallower or longer/shorter than the other side, and if so, ...
0
votes
0answers
7 views

Why is the E-mode polarization spectrum out of phase with the Temperature spectrum?

The E-mode polarization power spectrum of the Cosmic Microwave Background displays the same acoustic peaks that can be seen in the (more famed) temperature power spectrum. However, they are out of ...
1
vote
1answer
23 views

attractors of Mercury's spin-orbit relation

Mercury rotates at such a rate that the Sun appears to stand nearly still at perihelion, when the tide is strongest. Is there a mechanism that tends to adjust the orbital eccentricity to improve the ...
0
votes
1answer
51 views

If earth were the size of a marble would it be smoother than a marble? [closed]

As the title states, If earth were the size of a marble would it be smoother than a marble?
1
vote
1answer
70 views

If oxygen were pumped into space where would it go?

If an astronaut went into space with a sealed container of oxygen and opened it up in space and let all the oxygen go, what would happen to it? would it all just dissipate into some other particle or ...
3
votes
2answers
131 views

Why do objects all orbit in the same direction?

In a solar system or a planet that has many moons, why do their orbiting objects all orbit in the same direction? Is it possible for two orbiting masses to orbit in the opposite direction of each ...
3
votes
1answer
82 views

How did the moon's orbit become eccentric?

The Moon's orbit is more eccentric, 0.0549, than most planets. I can understand that planets get eccentric by disturbing each other like under the late heavy bombardment. And likewise for multiple ...
5
votes
2answers
142 views

Are those noise or stars?

So there is this huge picture by Hubble. Better yet, with the zoom tool And if you zoom to the maximum level, you can see a seemingly uniformly distributed dots of orange and blue. Are those ...
0
votes
1answer
23 views

How could eclipse happen on the same day in a different calendar? (45 AD)

According to the eclipse calculator I use (Alcyone), a partial eclipse 0.314 magnitude occurred August 1, 45 A.D. in Rome starting at 8:35am local time. This would seem to correspond to an eclipse ...
1
vote
1answer
41 views

Is there some upper limit in the moon size distribution?

The planets range hugely in sizes, Jupiter is more than 300 times as massive as Earth. But the sizes of the large moons seem to be uncorrelated with the sizes of the planets they orbit. Why doesn't ...
-1
votes
2answers
82 views

Southern hemisphere is short of radio telescopes? [closed]

In northern hemisphere, we have GBT, Arecibo, Parkes, Jodrell and VLA, while in southern hemisphere, only Australia has big radio telescopes. ALMA is in Chile, but it is in submm. It is not ...
3
votes
0answers
120 views

How can we be 13.2 billion light years from another galaxy?

How did we get 13.2 billion light years from the faraway galaxies being discovered with Hubble? If we all started near each other at the Big Bang, and we all travelled slower than the speed of light, ...
1
vote
2answers
68 views

The universe is dying vs the universe is ever expanding

How does the idea that the universe is dying (trumpeted as some big new revelation the past few days on several new sites I keep seeing pop up on google news) square with the idea that the universe is ...
2
votes
1answer
43 views

Configuration required to tidally heat Earth-like rogue planet

Could it be possible for Earth-like rogue planet to maintain large bodies of liquid water on the surface without a sun by relying mostly on tidal forces of a moon (or multiple moons). How big/far/fast ...
1
vote
1answer
90 views

Is it possible to have a part of space devoid of matter?

I have recently read this article and I am finding it a little hard to believe that there would be a place that is without matter. So, if there is a galaxy at the other side of the void, we would be ...
3
votes
3answers
142 views

Are there heavenly bodies between galaxies?

I do understand that galaxies were formed in the famous Big Bang. However, I also understand that if such an explosion occurs in empty space it will never form distinct galaxies, it should more or ...
1
vote
3answers
87 views

How do we know that other planetary systems aren't composed of antimatter? [duplicate]

How do we know that other planetary systems aren't composed of antimatter? If they never touch matter, then they don't annihilate. All their observable physics (spectra) are the same as matter, right? ...
-1
votes
1answer
77 views

Help plotting a trip to the Moon! [closed]

Take me to the moon! I know this is literally rocket science but, I would like any sources or formulas that would help me plot a trip to the Moon. I'm not sending anything, nor do I ever plan to, I ...
1
vote
1answer
88 views

What particles does a black hole emit when it evaporates itself?

Due to Hawking Radiation, after a very long time, a black hole will eventually disappear. But where does this "evaporation" go? What is this made of?
3
votes
2answers
271 views

What are the differences between matter, dark matter and antimatter?

I thought dark and anti matter were kinda the same, but after saw a video, they mention that dark matter is not antimatter but their explanation is a little fast so I got doubts. What are the ...
0
votes
1answer
39 views

Earth Rotation and Orbit Geometry

Let Line A be the projection of the axis of Earth's rotation onto the plane of the eliptic. Let Line B the line connecting the center of the Earth and center of the Sun. At what times during the ...
1
vote
1answer
32 views

Calculate Atmospheric Extinction Using Source Altitude Angle

I am trying to code up the following article http://dl.acm.org/citation.cfm?id=2349512 (alternative free access version) to calculate the light reflected from the moon to a given point on earth at a ...
2
votes
2answers
201 views

Is the ratio between earth's distance from the sun and the speed of light just a coincidence?

I was doing some calculations to see how hard it would be to observe the speed of light and discovered an interesting correlation between the speed of light and the average distance from the earth to ...
1
vote
0answers
41 views

how do you become an astronaut after graduating? will nasa accept a foreigner? can a foreginer get a full scholorship? what do i need to do? [migrated]

ive dreamed about it ever since i was six,and where i live people laugh at me when i tell them about this because for one,no ones ever been an astronomer in my country and two, im a girl. but ill do ...
2
votes
1answer
83 views

How much illumination do the background stars provide?

I'm trying to get a better understanding of what things look like in "outer space." The main problem I'm trying to solve right now, is how much illumination is provided by the background stars. Is it ...
1
vote
1answer
54 views

Why are so many sun-like stars found in multiple systems? How do planets form in such a situation?

It has been reported that perhaps half of nearby sun-like stars are found in multiple systems. Why is this so common, and how do planets form in such a situation? Kaitlin M. Kratter, “Sibling ...
2
votes
0answers
30 views

Has New Horizon's data updated Charon's orbital elements?

For years I've been fascinated with the mutually tide-locked bodies Pluto and Charon. In July 2012, The Astronomical Journal published an article The Orbit of Charon Is Circular by Buie, Tholen and ...
1
vote
0answers
37 views

Why would it matter to us if space is infinite versus being finite? [closed]

More specificlly, what are some of the differences for contemporary sciences and humanity if there are multiple universes versus just one? I ask because I'm writing a story and I want to put into ...
1
vote
1answer
25 views

What's the difference between the Julian and the Julian Ephemeris Day?

I'm making a code where I calculate the sun position in a given time. But I also want to learn astronomy with it. I'm following a .pdf to make the program, and in this .pdf it says The Julian Day ...
0
votes
0answers
12 views

What is the term for the point between a star and planet where a 3rd object will cast the largest shadow on the planet?

Is there a particular orbital configuration that would allow an object to orbit a planet while casting a stable shadow on a planet in said position? I would also be interested to know if there is a ...
4
votes
3answers
103 views

What types of signals is SETI (and other such efforts) looking for?

This seemed to be the closest group for this question. Every few months there are a few articles asking "Are we alone in the universe" which focus on the Fermi Paradox, the Drake Equation, and end by ...
3
votes
2answers
106 views

Do all planets have a van Allen radiation belt?

Earth has the van Allen radiation belts. Which other planets have one? Can it be determined if distant planets in other solar systems have one?
1
vote
1answer
50 views

What is exactly the “longitude of the perigee”

Some moon phase calculation algorithms (apparently derived from Duffet-Smith's book, example here) seem to use a parameter called "longitude of perigee at epoch". What exactly is this? Can I assume ...
1
vote
1answer
32 views

accuracy of an artificial satellite at certain magnitude

When we say that 'accuracy of gaia satellite is 10 $\mu$as at $V = 10$ magnitude in position and annual proper motion'. What does this mean. Does it change over time.
1
vote
0answers
26 views

Equation for solar radiation at a given latitude on a given exoplanet?

I'm trying to find equations that would help me determine the amount of solar radiation hitting a certain latitude on a certain planet given the following inputs: the degrees of latitude of the ...
3
votes
0answers
71 views

Why Earthian atmosphere is so thin?

Venus is somewhat lighter then Earth, yet has a much thicker atmosphere. One would imagine that the following should be true: During the formation phase, all inner planets had captured as much gas ...
0
votes
2answers
80 views

Can a astronomical telescope view objects on Earth

I am new to telescopes, and planning to buy an astronomical telescopes like "Celestron AstroMaster 114 EQ Reflector". Just curious to know that whether it can be used to view objects on earth ...
1
vote
0answers
67 views

What is space temperature around Earth?

What is the equilibrium temperature that a black body will reach at the Earth's distance from Sun?
2
votes
1answer
67 views

How long is the moon full

Is the moon the most full only for one moment As stated here and here Or does if stay the same full for a longer period of time (maybe because, the sun is grater then it, and light spreads out) ...
2
votes
1answer
55 views

How do I remove fungus from a telescope mirror?

I use a Celestron NexStar 130SLT Azimuthal Newtonian Reflector. I noticed that recently, due to the wet season, some tiny spots of what appears to be fungus have appeared. Having taking appropriate ...
0
votes
1answer
109 views

What makes the moon, a super moon

Caught a sight of moon tonight (by chance) and came in surprise that moon looks thrice in size to its usual size. Mostly called as Blue moon. Didn't succeed in getting the details and explanations ...

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