Questions tagged [solar-system]

Questions regarding the Sun and objects orbiting it.

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6
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2answers
83 views

What is the definition of the “solar mixing ratio”?

What is the definition of the "solar mixing ratio"? Specifically, I'd like to know why the ratio of H2 and He is 0.84 and 0.16 at the "solar mixing ratio" as shown in Table I in The Galileo Mission.
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2answers
307 views

Are there Earth rocks on Mars?

Certain meteorites found on Earth have been established to come from Mars: a giant impact ejected rocks from Mars, these rocks traveled through interplanetary space, and went through the Earth's ...
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1answer
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How do we define “up and down” in space?

Every model of the solar system seems to follow a specific orientation in which the upper side of the system is Earth's north half and the lower side of the system is Earth's southern half. So is ...
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0answers
54 views

Longest time after an image was taken when a new solar system body was discovered from it?

This answer to If there's nothing special about Pluto, why was it discovered so early? says: In fact, often objects are discovered to be in pictures from long ago, such as Orcus, discovered in 2004,...
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1answer
4k views

Closest star system to Alpha Centauri?

The closest star system to our Solar System is Alpha Centauri. But is our Solar System the closest star system to Alpha Centuari? If not, which star system is?
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2answers
10k views

Is Jupiter a failed star?

The elemental make-up of Jupiter is about entirely hydrogen and helium, along with a very small fraction of the atmosphere being made up of compounds such as ammonia, sulfur, methane, and water vapor. ...
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1answer
887 views

How frequently do Jupiter & Regulus have triple conjunctions?

I am wanting to know if the triple conjunction of Jupiter with Regulus in: Sep 10, 3 BC Feb 7, 3 BC & May 8, 2 BC with Jupiter later having a conjunction with Venus in Jun 17, 2 BC has happened ...
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3answers
179 views

What would happen to the Earth if the orbit of another planet in the Solar System was disrupted by a cataclysmic collision with a large body?

There's plenty of speculation about what would happen if a large asteroid collided with the Earth itself, but less about the effect on Earth of a large asteroid or even a moon or minor planet ...
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3answers
85 views

Looking for a Solar System Simulator including the smaller celestial body, for macOS

I am researching for a sci-fi novel that will happen in 2136. For this I would like to know specific positions of "smaller" celestial bodies in our Solar System. An example can be the dwarf planet ...
3
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1answer
214 views

Has a near earth object in heliocentric orbit ever been bright enough to be visible to the unaided eye?

The question Can we see asteroid 1998 OR2 with unaided eye? got me thinking. Space.com's Vesta: Facts About the Brightest Asteroid says: Vesta is the second most massive body in the asteroid belt, ...
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0answers
126 views

Help identifying a very slow-moving object during meteor shower photography

I just wonder if anyone could shed any light on this puzzle. Two nights ago whilst I was out photographing the Lyrids meteor shower from the UK something else showed up on my images when I checked ...
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0answers
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Have meteor showers been predicted for planets or solar-system bodies other than Earth? Have attempts been made to detect them?

Per the linked Q's and A's in Why do particles from a comet that result in meteor showers spread out mostly along the comet's orbit? and it's answer, meteor showers happen on Earth when it passes ...
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2answers
530 views

Why do particles from a comet that result in meteor showers spread out mostly along the comet's orbit?

My understanding of the meteor showers that repeat yearly is that the Earth passes through the orbit of a comet that is nowhere near us, and might not even exist anymore, yet it's orbit is filled with ...
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2answers
6k views

How can comets have tails if there's no air resistance in space?

I understand that solar radiation causes material to vaporize out of a comet into dust but why does the dust then trail behind the comet like a "tail"? Assuming gravity is the only applied force ...
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1answer
94 views

Is there any thing special with an axial tilt of roughly 25°?

Half of the planets in the solar system have an axial tilt of $25.5\pm 3^\circ$: earth (23.5°), mars (25.3°), saturn (26.7°) and neptune (28.3°). If random collisions in the early solar system caused ...
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0answers
51 views

Binary stars and gas giant formation

Say there's a young s-type binary star system with 2 Sun-like stars. From what I understand for a stable orbit to be possible, a planet's farthest orbital point from its host star has to be around 1/5 ...
15
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1answer
250 views

The compatibility of the Grand Tack hypothesis with the “core-warping impact” theory of Jupiter's diffuse core

In recent years, the Juno mission revealed that Jupiter's core was much more diffuse than astronomers had expected. One theory is that "within a few million years" of its formation, Jupiter ...
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1answer
58 views

How close would the sun have to get to a supermassive black hole to have Jupiter stripped and slingshot into interstellar space?

Please make whatever assumptions are needed. Assume sun approaches black hole on some sort of hyperbolic trajectory. Assume size of supermassive black hole is same as the one at center of our galaxy....
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1answer
158 views

So, what, exactly, is a tropical period?

From timezone.com's On the Units of Time Part III: The Year February 19, 2001, by Edward Hahn: Uh, Oh…He’s Going to Ask That Question Again… So, what, exactly, is a year? @PM2Ring's comment FWIW, ...
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1answer
39 views

Why were solar constant measurements before TSIS-1 all about 0.3% high?

Phys.org's Solar energy tracker powers down after 17 years says: "The big surprise with TSI was that the amount of irradiance it measured was 4.6 watts per square meter less than what was ...
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2answers
899 views

Is a year really 365.24 days, or is it 365.2564 days like I remember?

The NPR News item and podcast Spring Starts Today All Over America, Which Is Weird includes the following: But why isn't the time of the equinox the same each year? The short answer is that the time ...
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0answers
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Satellite grids around other planets [closed]

We send a lot of rovers to Mars, as interesting as the planet could possibly be. But why are we not putting satellite grids around planets that could transmit superficial probe data at the very least?...
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1answer
82 views

What would be the best inertial reference frame to describe objects in the solar system (other than the solar system's barycenter)?

For the purpose of a project, I require the components that describe the inertial frame to be as independent as possible from solar system bodies itself. Since the solar system barycenter is itself ...
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4answers
557 views

Why is there no concavity in the orbit of the moon around the Sun?

Such questions have been asked here and I have read the answers some of which are quite informative. However, I want an answer that's straightforward. I have gone through the following paper by A B ...
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1answer
114 views

How frequently are other planets in the Solar system hit by meteorites?

How frequently are other planets in the Solar system hit by meteorites? For example, is the rate per unit area about the same?
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1answer
179 views

Are the planets Mercury, Saturn, Uranus and Neptune losing mass?

My understanding is that Venus, Earth, Mars, and Jupiter are all losing mass due to their gravity, temperature, and the solar wind. But what about Mercury, Saturn, Uranus, and Neptune? Mercury has a ...
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1answer
48 views

Is it only possible to look at solar systems with stars at least as old as ours to be able to find intelligent life?

Assuming the speed it takes to development intelligent life is the same in all solar systems, would we need to look at exoplanets with stars as old or older than ours to find intelligent life? A young ...
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2answers
102 views

Which celestial body's length of day is closest to that of Earth?

I know the planets Mars and Eris are among bodies that have the most Earth-like mean solar days (about 24.67 and 25.9 hrs). Among moons there is Mimas of Saturn which has one of the most Earth-like ...
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1answer
182 views

The Solar System formation

I've recently watched one conversation (I won't post a link since the conversation is not in english) involving a physicist (at least he claims so), who spoke about probabilistic estimates of the ...
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2answers
124 views

Largest body in the solar system that a baseball thrown by a professional pitcher could escape

What is the largest (most massive) known body in the solar system that a professional pitcher could throw a baseball off of, i.e. that has an escape velocity lower than ~102 MPH? (45.33 m/s)
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Is the angle of the Earth's orbit on the Galactic plane changing (towards 180 degrees)? [duplicate]

Currently the angle of Earth's orbit is aroun 60 degrees on the Galactic plane. But is this angle changing?
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1answer
218 views

Precision in the measurement of the distance to the Sun

How precisely can the distance to the Sun be measured? Wikipedia says the distance to the Moon can be measured upto millimeter precision. But Wikipedia article on distance to the Sun says only about ...
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If the hypothetical planet beyond the Kuiper belt exists, is it likely there are even more planets farther outside?

Since 2016 there are hints that a (probably) ice giant planet may exist far beyond the Kuiper belt. There are speculations that it may be a rogue planet captured by the Sun. But is it likely that ...
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1answer
153 views

What is happening with these solar particles detected near the Sun that is so newsworthy?

Phys.org's Team identifies low-energy solar particles from beyond Earth near the Sun links to the open access ApJ article Properties of Suprathermal-through-energetic He Ions Associated with Stream ...
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1answer
1k views

What does the Sun look like from Eris at its aphelion?

At its aphelion (most distant location from the Sun) the outermost-known planet Eris is about 100 times as far from the Sun as Earth. What does the Sun look like from Eris' surface? Is there still a ...
4
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1answer
114 views

Peculiar Amplitude of Earth's Orbit in Z Axis

I'm currently building an N-body simulator for my masters project and I'm using JPL's Horizons system to compare against. I started with just a couple orbits and everything seemed to be working ...
4
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1answer
156 views

How is the Gould Belt younger than the sun?

Our sun is located in the Gould Belt, a group of stars which is thought to be 30 - 50 million years old. However, the sun formed 4.6 billion years ago. Did the belt form around us?
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1answer
110 views

Is there any planet or satellite in the solar system in the process of getting tidally locked?

According to Tidal locking The effect arises between two bodies when their gravitational interaction slows a body's rotation until it becomes tidally locked. Over many millions of years, the ...
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0answers
46 views

Who first named the planets Mercury, Venus, Mars, Jupiter, and Saturn? [duplicate]

Who first named the planets Mercury, Venus, Mars, Jupiter, and Saturn? Agnes Clerke's Catholic Encyclopedia article "Astronomy in the Bible" § Planets claims that "Venus and Saturn are the only ...
5
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1answer
168 views

Is there a verification of the solar system barycenter as it is theoretically determined?

The barycenter of our solar system is not the sun, but a changeable location outside of the center point of the sun. A often used diagram of that relation is shown below, originated from the Wikipedia ...
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2answers
532 views

Where can I find Helium 3 in our solar system?

What are the best locations within the solar system to find Helium 3 excluding the Sun? Where is Helium 3 most abundant after the Sun?
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1answer
36 views

For any given meteor shower in a given year (e.g. Quadrantids, now) where can I see a rough prediction of how many days it will last?

For a given shower the rate hitting the Earth's atmosphere versus time is usually a peak with a width of a few days, though there are some exceptional unicors. Is there a place where I can view this ...
3
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1answer
89 views

What is the current angle of motion of the sun with respect to the Galactic Plane?

I understand that the solar system oscillates in its motion around the Milky Way. However at any given time, there must be a specific angle between the current direction of the solar apex and the ...
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2answers
94 views

Visibility of a planet on the other side of the Sun

Context: I've been having a discussion with my vectors and mechanics professor (course Mathematics BSc) about a problem on a recent coursework. The following is the model I came up with. I'm not an ...
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0answers
55 views

Does the axis of solar system precess during it's motion in the Milky way galaxy?

The plane of solar system makes an angle of 60° with the plane of galaxy. So, the axis of solar system should make 30° angle with the galactic plane. Like the axis of Earth precess over a long period, ...
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0answers
28 views

What is the typical chemical composition of the most common asteroid types?

I'm trying to make a semi-scientific accurate game where you can find/mine asteroids. I want the composition of asteroids, and how common they are to be correct. Or at least as close to correct as ...
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1answer
223 views

What's the difference between semi-major axis and apoapsis?

The semi-major axis is half of the diameter of the major axis of an ellipse by definition. So how does that make it any different from apoapsis, the furthest point an object is from a parent body in ...
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1answer
207 views

Delay of Moon passing a defined meridian each day

On the website Lunar Synodic Curve a nice image of an Moon analemma is shown together with an explantion on the reason why for the different phases of the Moon the images have to be taken with 24h ...
4
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1answer
229 views

Could Planet Nine be much smaller than thought previously?

In 2016, Caltech astronomers began testing a Planet Nine hypothesis to explain the eccentric and inclined orbits of distant dwarf planets such as Sedna, 2015 TG387, Niku, and 2012 VP113. The ...
4
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0answers
59 views

Why do CME's “zig-zag” on their way to Earth?

This answer to When a coronal mass ejection (CME) hits a spacecraft, from which direction will the particles come? states: A single CME will impact a spacecraft from only one direction, but that ...

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