Planets Definition and 510 Threads

Hi, this may be a very basic concept, but I'm trying to develop coordinate systems for other planets from their right ascension and declination and prime meridians so that, given a location on that planet, you could visualize the sky and its stars.. I've been reading...

Hi all. This may be a stupid question to some.. But please do answer it. Why do planets move in an elliptical path? Why only ellipse? Or even a circular path for approximation? Why not a path which has corners? Like an octagon or a square?

Hey Guys! I've been doing a few equations in regards to planetary escape velocity and gravitational force. The below links have the escape velocity of listed planet on the left side of the board, the gravitational force between the Sun and given planet on the right side. In the middle of the...

To keep track let's take a trip to 'Imagination Land' (no not the south park version!). Now imagine that the 8 planets and pluto in the solar system are places where humans can live, would the age rate differ from planet to planet? Now let's get back to reality. We may be able to send humans to...

Homework Statement If the Earth did not spin on its axis, would the other planets still appear to move across the sky? Justify your answer. Homework Equations N/A The Attempt at a Solution If the Earth continued to rotate around the sun but NOT on it's own axis then wouldn't...

Homework Statement Indicate the positions of the planets in the sky at the times given. I am struggling on how to answer these questions any help would be great any help would be great. thanks pf! The Attempt at a Solution 1) Jupiter at eastern quadrature around sunset? Jupiter...

Homework Statement The precision in measurements of radial velocities by the Doppler effect is currently 1 m/s. Can a Jupiter like planet orbiting a star similar to the Sun at a distance from the mother star equal to the Sun-Jupiter distance be detected?' (Use www or other sources to find the...

In our time epoch and location in space, it seems that even if we received signals of some extraterrestial civilization, or detect some extrasolar inhabitable planet, unless we would achieve some huge breakthroughs it would be impossible to ever visit each other. But can we conceive of other...

I imagine it depends on the chemical makeup of their atmospheres.

Hi. First post here. I'm writing a sci-fi novel, and the above is what I need. Thanks in advance for your help. By "similar surface gravity" I mean that someone from the smaller world could move to the heavier world with a minimum of health risks (they're going to have enough trouble with the...

What exactly does it take to figure out the orbital parameters or planets and what's the Math behind it? Can it be done using only a telescope or is it necessary to send a probe?

Do white dwarf planets ever die and eventually there will be no remains of the sun? What will happen to the gas giants with no sun to orbit?

Hello All, A curious person here would like to know if a planet gains gravitational force as it rotates around the center of its galaxy. From what I understand this speed is quite impressive (the speed at which we travel around the center of our galaxy) so I'm wondering if the sheer mass of...

Hello, first post here. I'm trying to wrap my head around something here and I'm wondering if anyone can help. I've read that all terrestrial planets have basically the same chemical components - Iron, Silicon, Oxygen, etc - in roughly the same percentages. I also read that the composition of...

Homework Statement A person standing on the surface of a planet has a weight of 250 N. Suppose he goes to another planet that is the same size(volume) but twice the mass(more dense). What would his weight be on the second planet? Homework Equations g=Gme/re2 The Attempt at a Solution...

hello I am confusing about a physics problem right now. instead of gravity, two planets are connected by a spring with spring constant K. And since the mass of one planet is much bigger than that of the other. So, lighter planet does circular motion around the heavier planet. Then, it asks ω...

Hi, With today's technologies, if our exact solar system were at a few light-years from us, could we detect its planets ? /Nico

I'm trying to get a basic understanding of Earth's origins in order to teach an advanced oceanography course to high school students this summer. The course starts with one lecture on the origins of the universe, solar system, the earth, and the ocean. I'm trying to understand, why did...

How long does it take for earth, mars, and Jupiter to line themselves up to a certain separation angle. Background information: I am doing this project where we are trying to do a Hohmann transfer from Earth's stationary orbit to Mars and doing a flyby gravity assist at Mars and shoot for...

Working on a story idea that involves binary worlds. To keep the math simple I'm assuming the planets to be Earth sized, and mass, orbiting a star identical to the sun. I managed to find someone to help with the first equations and discovered that based on the time it takes them to orbit each...

How is electromagnetism different from gravity in that accelerated objects radiate EM waves when accelerated in an electric field but no gravitational waves are generated when objects are accelerated in a gravity field? Why do not planets orbiting the sun generate gravitational waves and...

1. Determine the ratio of the masses of the planets Earth and Mars by using only information about their orbital periods and orbital radii about the sun. Assume the planets can be treated as points with mass and assume circular orbits. Homework Equations Gravitational force: F_g = G m_1 m_2 /...

Why planets are "spheres" I was reading the specifics on why large bodies in space, such as planets, are pulled into spherical shape and they had a very technical term for the process. Does anyone know what I'm talking about?

If warp drive was possible, how could it affect the orbit of planets that are close to the warp? I'm not sure how to define how close. Is there a minimum distance the spaceship would need to be from other planets, so that it has no effect?

I am not so good in astronomy but i had desire to know what was in there right from my childhood. can you please clear me the following questions i have in my life about space.. 1.Why does planets follow the same path or trajectory to orbit around the sun and why do they revolve around the sun...

This paper, http://arxiv.org/abs/1311.6806, discusses Kepler mission results. The authors deduce that 5.7% of sun-like stars have an Earth sized planet orbiting in the habitable zone. That is a shockingly large number, IMO. Considering there are an estimated 26384 class G class stars within 324...

Hello , it is said that at the center of planets and stars there is zero gravity because , assuming spherical geometry, the gravity from all sides comes together and cancels out in the middle and everything that is in close approximation to it. Now that said I also read that the pressure at sun...

WIMPs and "Ghost Planets" There's very little known about WIMPs, from my understanding, but I believe there has been some speculation that they interact with each other less-than-weakly, and they most certainly do have a gravitational presence. So, if WIMPs were to interact with each other in...

Homework Statement What would be the temperature of a spherical asteroid located between Mars and jupiter, twice as far from the Sun as Earth? The asteroid has no atmosphere, and its albedo is 0.15 Homework Equations the solar constant at venus is a factor of (150/108)^2 larger...

Homework Statement The three planets (v1, v2 and v3) in the diagram all have similar mass and are in a line equally spaced so that v1 and v3 are orbiting around v2 synchronously. If the mass of each of the planets are M and the radius of the orbit is R, what is the orbital period...

Hey I've been trying to make a basic animation which involves launching a spaceship from one planet to another. Both planets orbit at different rates from the star with fixed speeds. The spaceship also has a fixed speed from start to finish. What i don't understand is how you measure...

I am trying to write a program to show the flight of a satellite in the neighbourhood of two large planets. In all of this the mass of the satellite is negligible. I have the potential energy from planet1 = pe1 and the potential energy from planet2 = pe2 and the kinetic energy of the...

how the planets get in spherical shape if the they are formed by a big explosion ?

Hi all, I was just wondering whether there is a proper difference between a moon and a planet. The only answer I've been able to find is that moons orbit planets, and planets orbit stars. But in reality, planets and moons both orbit their common centre of mass. So to frame my question...

If the reason why the planets orbit around the sun is the deviations in the fabric of spacetime,what keeps the planets from crashing into each other? Like if I put a boulder on a trampoline and then I put a baseball next, the baseball would go toward the boulder. I think it could be dark matter...

I'm working on a video game set in space, and I'd like my portrayal of the galaxy to be as scientifically accurate as is feasible. I've been looking into metallicity functions, but I can't make any sense of what I'm seeing, and I don't even know where to start on the subject of algorithms for...

force of gravity decreases with distance from the planet.This means the distance from the center of the planet.Is the center only producing the gravity?If i get close to the center the Will the gravity increase towards the center or away?because if the planet is perfectly spherical with uniform...

http://cosmiclog.nbcnews.com/_news/2013/04/18/17811465-kepler-mission-makes-big-splash-with-possibly-habitable-super-Earth's Just announced 18 April. "Kepler-mission-makes-big-splash-with-possibly-habitable-super-Earth's". These are in constellation Lyra. I can't evaluate how definite or...

Homework Statement Two planets A and B have relative velocities 0.7c. They can observe the birth of two stars, C and D. According to planet A, star D was born 10 years before star C was born. According to planet B, star C was born 20 lightyears farther than star D. What is the time...

If WIMPs are the explanation for dark matter should it clump together to form dark matter "planets"?

Do planets "wave" in their orbits? Hi, I was wondering if a planet moves up and down as they orbit the Sun due to the differing inclinations of the other planets? In other words do the planets move in a wave like motion in their orbits or is it smooth? Thanks in advance.

I'm looking for a more or less definitive answer for the earliest time when rocky planets could form. I saw one thread in this forum that addressed this, but there was no resolution. My guess is two to three billion years from the start to allow for several generations of supernovae to put out...

Question: What would happen if a planet's trojans were removed or added to? And I don't mean "very little" please. What exactly would happen, for example, if a planet's huge trojan asteroids were pushed out of orbit into the Sun? What would happen if L4 and L5 had asteroids as big as the planet?

[FONT="Verdana"]I learned on the textbook that human calculated the orbital of planets that near the Earth first then based on the difference of the actual data of the planet orbitaland that of human predicted, human calculated out other planets' orbital and predicted some planets like Neptune...

Can dark matter form planets and dark matter life?

Today an interesting question came to my mind... I have heard that when is a conjunction of planets to Earth, it affects our weight. If the conjunction occurred at larger planets to Earth - Jupiter, Saturn, Uranus, Neptune (in one line with Earth) - how it affects our weight? Surely we will...

I just posted a question to ask for help on the Calculus & Analysis section to determine how fast planets go into stars. I should give a little background, in addition to pointing you to my latest two short papers: http://arxiv.org/abs/1301.4229 and http://arxiv.org/abs/1211.1984 I have...

I am an astronomer with a research question: I want to evolve this equation for planet distribution: \frac{{\operatorname{d}}f(P)}{{\operatorname{d} \operatorname{log}}{P}}= k_P P^\beta \left(1-e^{-(P/P_0)^\gamma }\right) as a function of period ``P'', by using an equation for change of P. I...

planets in the solar system lie almost in a plane. Is this because the sun is rotating on itself ?

"Determine the relative distances of each of the planets from the Sun given [...]." Homework Statement Devise methods to determine the relative distances of each of the planets from the Sun given the information available to Copernicus (observable angles between the planets and the Sun...