Questions regarding celestial bodies in orbit around a star.

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11
votes
3answers
200 views

Why do (most of) the planets rotate counterclockwise, i.e. the same way the Sun does?

Referring to the mechanisms explaining the solar system formation and to the initial rotation of the gaseous cloud that collapsed, I understand easily why the planets orbit the Sun the same way this ...
1
vote
2answers
101 views

Why don't planets give off their own light? [closed]

Why don't the planets glow like stars?
2
votes
1answer
46 views

Weight of a celestial body

How do astronomers find out the correct weight of a planet tough there isn't any direct means to weigh them?What technique do they use?Just curious!
3
votes
3answers
132 views

Inclination of planets

Why do the planets have roughly the same inclination with respect to Earth? Looking at the inclinations, which I got from http://www.astronomynotes.com/tables/tablesb.htm , we see that Mercury has ...
1
vote
1answer
19 views

Do planetary radio frequency change upon alignments?

If Neptune would align Uranus, would the radio frequency perceived on Earth increase? Are the radio antennas on NM capable of getting the 2 different radio frequencies feom both planets or would they ...
9
votes
2answers
668 views

Is it Possible for Planetary Bodies To Exist In Close Proximity Without Adverse Effects?

There are several sci-fi movies where planetary bodies are shown in the sky in order to indicate that the characters are on an alien planet. A good example is in Predators (2010): Is it actually ...
4
votes
0answers
60 views

Are there large underground caverns on Mars?

Scientists talk about the possibility of life underground on Mars, and I assume they are talking about microscopic life that can live in small gaps in the soil or rock. But is there any evidence that ...
4
votes
1answer
59 views

Any cheap (less than 100 euro) telescope for observing Jupiter? [closed]

The moon is not challenging. I would like to observe the big planets and their rings.
1
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0answers
13 views

Is Mars' mantle homogeneous or heterogeneous and what might this say about mantle convection?

A supervisor of mine made an off-hand comment about the fact that Mars used to have plate tectonics, and there is evidence that Mars used to have plate tectonics, however now it does not. The theory ...
0
votes
2answers
50 views

Is Mars visible from naked-eye from Michigan (47N, 88W) these days?

Is Mars visible at night sky of Michigan these days? I was trying to search for Mars from Michigan (at elevation of 30 deg and azimuth of 220 deg) around 11:45 PM with binoculars of 20x60 but didn't ...
1
vote
1answer
61 views

Why do we not send diggers to Mars if we think there's underground water?

A friend of mine asked me this question: If we have a guess that there may be underground water on Mars, why do we not send rovers with diggers? I do have a few ideas, but I want alternative ...
4
votes
1answer
156 views

When will all eight planets in our solar system align?

Ignoring expansion of the universe, entropy, decaying orbits, and interference from any bodies colliding with or otherwise interfering with their orbits, will the eight planets known planets in our ...
-1
votes
2answers
73 views

What would happen if a planet is removed from the solar system? [closed]

More exactly what would to happen to us/Earth in general if any of the gas giants is removed by magic from the solar system ? How long would it take after such change before we notice it ? How major ...
1
vote
1answer
79 views

Why planet's orbit is not perpendicular or random ?

Why planet's orbit is not perpendicular or random ? It always seems each planet is revolving on the same geometric-plane around the star.
1
vote
0answers
34 views

Intrasolar planetary surface temperature change divergence from Earth

Considering the vast amount of insulating gas emitted by human activity on Earth without a coincident release on all other planets in the solar system as well as the phenomenon that planets in a solar ...
4
votes
1answer
117 views

How small can a planet be and still have Earth-like gravity?

A planet made from denser material than Earth might have equal gravity to Earth but a smaller radius. How small can a planet be and still have Earth gravity? Ideally it should be habitable by humans, ...
5
votes
1answer
227 views

Best telescope for the viewing of Nebulae, Stars and Planets

So, I am a 15 year old interested into astronomy. My father used to have a reflector telescope, but was never so serious about it that he could recommend me a good telescope. I am looking to buy a ...
3
votes
1answer
53 views

Movement of the satellites of the planets . . .

Is the movement of the satellites (moons) of a planet coplanar, like the planets being coplanar around the local Sun?
4
votes
2answers
124 views

Why don't planets and asteroids have (cometary) tails?

Comets have tails. We all know that, and a lucky few have seen the better known. So why don't the planets (e.g. Earth, Mars) have tails? Why don't asteroids don't have tails?
6
votes
2answers
67 views

Present distances between planet. How can I find them?

It's "commonly known" how distant are our solar system planets from Sun. But we can't easily say that about planets, which distances can differ greatly, without some observations (or simulations, ...
2
votes
1answer
83 views

What is the orientation of planetary orbits?

I'm working on a planetary motion simulator. I've been working through the equations anomaly, eccentricity, etc. The one thing I'm curious about is if all the ellipses are oriented the exact same way ...
3
votes
1answer
77 views

Do planetary surface temperatures change in unison in a solar system?

Are there any known correlations between the changes in planetary surface temperatures in a solar system? If so, do the farthest planets have smaller albeit correlated changes?
2
votes
1answer
50 views

What method is used to calculate the 'quality' of a solar/planetary image?

What sort of algorithm is used to calculate the relative quality of an image, such as is performed by PIPP, Registax, or Avistack? Such applications take planetary or solar images and prior to ...
3
votes
2answers
65 views

How are rogue planets discovered?

Planets are usually found by observing a star and waiting for the light level to drop when a planet passes in front of it, but what about rogue planets that don't have host stars?
4
votes
3answers
552 views

Which planet is also the name of an element? [closed]

Which planet is also the name of an element? I came across this question on cosmos quest and need and answer
1
vote
1answer
53 views

Rotational speeds of the material forming planets should increase, not decrease

We know that planets form as a result of gaseous material revolving around a center of mass that froze to form planets. However shouldn't the angular speed of that matter increase as they go closer to ...
2
votes
1answer
108 views

If oxygen was abundant in Neptune, would there be combustion?

Since Neptune/Uranus have high percentages of methane, wouldn't it be highly likely that there will be combustion (triggered by the lightning storms or any other factor) if oxygen was abundant? And ...
2
votes
2answers
158 views

the most accurate system that can show the positions of planets at my birthday [closed]

My birthday : 4 December 1982 If you have such astronomical calculator on your computer please send me the result ! Alternatively if you know an online astronomical service for my purpose please ...
5
votes
3answers
182 views

Is there anything special about our position in the galaxy thats necessary for life?

It's a fact that our planet's location from our parent star (among other factors) is of crucial importance to the existence of life. But can our position in the galaxy be considered a factor when ...
2
votes
2answers
45 views

How do kepler orbits account for planetary migration?

This article got me thinking if kepler orbits explain how a planet moves in a solar system how can a planet migrate as explained in the article. At some point don't the kepler orbits must need some ...
1
vote
2answers
131 views

Would Venus have any significant effects on Earth if its orbit were entirely within the habitable zone?

If Venus was entirely inside the habitable zone, or life zone, would its proximity to the Earth provoke any remarkable changes to the Earth?
7
votes
3answers
144 views

Why are planets spherical?

I am a complete novice when it comes to astronomy, but someone asked me the above question casually. It seems as though planets are all roughly spherical, whereas other celestial bodies aren't ...
4
votes
2answers
86 views

Is the discovery of Alien or Extra Terrestrial Life a function of the science of Astronomy?

Is the discovery of Alien or Extra Terrestrial Life a function of the science of Astronomy? When i read astronomy articles on the search for new Planets or discussions on Mars a lot of the topic is on ...
3
votes
1answer
74 views

Which planet or moon has all resources that can be used to sustain life in a controlled biosphere? [closed]

Now that we are making it to Mars, continuing onward, in an effort for humanity to civilize other planets, not just setting up residential colonies, but to mine minerals and carry on geological and ...
4
votes
2answers
79 views

What does the term alien planet actually refer to?

This article left me wondering what do they mean by the term alien planet? Aren't all planets simply alien by default, or do they mean planets outside our solar system are alien? Do they mean there is ...
8
votes
3answers
353 views

Why are orbits elliptical instead of circular?

Why do planets rotate around a star in a specific elliptical orbit with the star at one of it's foci? Why isn't the orbit a circle?
3
votes
2answers
176 views

Why do the planets in the Solar system stay in the same orbital plane?

An earlier question addressed why all planets formed in the same orbital plane, but how is this angle maintained? What prevents the planets from taking on a different orbital plane?
4
votes
3answers
107 views

Find distance from star to star?

How do you find the distance from a star/planet/black hole to another? I know people can calculate the distance from Earth to a star, but what about from one to another?
12
votes
4answers
366 views

Doesn't gravity attract objects in space until they collide?

If the formula to calculate the force of gravity of two objects is: $$F1 = F2 = G * (M1 * M2/r^2)$$ Why do planets stay in orbit? Or is there another formula at work?
10
votes
4answers
222 views

How would I measure that I'm at a pole?

How would a person measure that he is at a planetary pole? My first inclination is to use a sextant to ensure that the Sun remains at a constant inclination. However, due to the orbit around the Sun ...
12
votes
3answers
264 views

Does a planet's mass or gravity affect the height of it's mountains?

According to this Wikipedia page, the top five highest mountains on Mars (and the highest on Venus) are all taller than Mount Everest (and Mauna Kea as measured from the ocean floor). Does a planet's ...
12
votes
2answers
208 views

Is there a upper limit to the number of planets orbiting a star?

Our sun has 8 planets orbiting as well as a number of dwarf planets. Are there any calculations that hint as to whether this number is close to some theoretical maximum value or are we simply an ...
7
votes
1answer
64 views

Do planetary rings have geometric bounds?

Are there any bounds on where a planetary ring can form and maintain orbit relative to the planet? Do they have to be in a circular equatorial orbit? Is there a min or max altitude, say with respect ...
8
votes
1answer
141 views

Changes to Earth's orbit

Any time a spacecraft comes in close proximity to a planet and if the spacecraft has the right angle then it is able to use the planet's velocity to move itself further into space. According to ...
-2
votes
1answer
187 views

Is it possible the Nebular Hypothesis and Planetesimal Theory are not correct? [closed]

For almost 3 centuries now the Nebular Hypothesis and Planetesimal Theory have become the preeminent explanations for how the Solar System and Planets evolved. Yet there is still no explanation for ...
5
votes
1answer
104 views

What effects do other planets have on the solar system?

For instance, Jupiter is the biggest planet in our solar system. Due to it's gravitational mass it can deflect meteorites and protect Earth from the Oort cloud. While these are positives, the ...
7
votes
1answer
180 views

What reason is there to doubt the existence of the hypothesised planet Tyche in the far distant solar system?

Please note, I do not necessarily believe in its existence, just after a scientific (hence, non-Wikipedia) reasoning to doubt the planet's existence, other than the "we would have seen it" argument. ...
8
votes
1answer
138 views

How do we detect if a planet has a liquid core?

In case of Earth, we have many hints about the internal structure of our planet, from what I know, the most important of which is analyzing seismic waves. Do we have any instruments to detect if ...
12
votes
1answer
139 views

How do/did we figure out that planets move in orbits?

I've learned that planets move in orbits around the Sun, but I really don't know how I would come to this conclusion myself. I've only seen planets in the sky a couple times (knowingly), and I am ...
2
votes
0answers
64 views

How can I create tracks of the planet's orbits on my computer? [closed]

I'm wondering if there's any good computer software for tracking the orbits of planets over time. I like to see the orbit's trails against the sky background. I'd prefer something that's free and of ...