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Questions on astronomical objects orbiting a star massive enough to be rounded, not massive enough to cause fusion, and which have cleared its orbit of planetesimals.

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1answer
86 views

We are in Green Lake, WI, 8/12/18, seeing bright orange “planet”/“star” almost due South, perhaps 20 degrees above horizon, what is it?

I have a “sky” app on my ipad and expected it to be Mars, but my app shows Mars just below horizon and closer to East. Oh, I should add that we saw this about 10:15 tonight. Hanging out watching ...
2
votes
1answer
58 views

Why are gravitational perturbations stronger at larger semi-major axes?

Why are mechanisms such as the Kozai-Lidov effect more prominent at at large semi-major axes? If we had a binary system of a primary and secondary body, with the third perturber as the Sun. Why is it ...
2
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0answers
173 views

Orange light in sky

It is 1:15 am, 8/10/18 in Indiana. I looked out my kitchen window and saw an orange light to the north.. color of a street light but clearly out in space. Sitting about as high as a full moon at ...
3
votes
1answer
87 views

Is the dot on the photo - Mars?

The below photos were taken yesterday (August 4, 2018) at about 10 p.m. from the plane over the Black Sea. We were seeing the light dot on the left for at least 10-20 minutes. It looked like a bright ...
6
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2answers
292 views

Currently proposed ways to distinguish between a really big planet and a really small star

The Next Big Future article Rogue Exoplanet 12.7 times bigger than Jupiter is 20 light years away Astronomers using the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) have made ...
3
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2answers
89 views

Why does Jupiter atmosphere does not get thinner on edges

Looking at Jupiter image the atmosphere edge of planet is very sharp as if it has solid surface which is not as it’s gases giant and there should be some thinning of atmosphere like we see around ...
2
votes
1answer
56 views

I have a Model 36050 telescope

My Model 36050 telescope came with the H6mm, H20mm and the green filtered moon lenses. It has a 360mm focal length and a 50mm diamiter. What can be seen with it?
4
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2answers
73 views

How to know the orbital and physical characteristics of the solar planets with only a non-professional telescope?

I have always been fascinated to see that with so little knowledge, scientists have succeeded in discovering the planets of the solar system, and have succeeded in defining them by their masses as ...
2
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1answer
41 views

Beginner looking for extra eyepieces for telescope

I have a Bushnell Voyager Reflector telescope. It came with 2 eyepieces: k4mm and k20mm. And I am trying to find additional eyepieces to zoom in further on planets and stars, but the bushnell website ...
1
vote
1answer
85 views

Could an Earth-sized planet be cold?

This question poses the question of why the Earth is still hot after 4.5 billion years, and the primary reasons were: (1) heat from when the planet formed and accreted, which has not yet been ...
1
vote
1answer
62 views

Struggling to use my new telescope

I recently got my first telescope, a Bushnell reflector telescope. I spent a good while setting up my alignment. And I can see the moon perfectly! I went to look at another, Mars. I got it aligned in ...
2
votes
1answer
80 views

Strange bright light in the sky flying fast [closed]

I was out with my dad on our porch watching the stars with our telescope. after awhile of looking and taking pictures I noticed something strange in the sky. There were two airplanes flying close to ...
1
vote
1answer
45 views

Why does in-the-sky.org say that Mercury is not visible from Taipei these days?

I know that viewing Mercury is a challenge, but I'm fairly close to the equator and Mercury was at greatest elongation just a week ago. In-the-sky.org says: All around the world, Mercury is ...
2
votes
2answers
5k views

Saw a bright orange object in the sky. What was it? [closed]

Some friends and I were backpacking in the mountains, and at night we saw a very bright orange object in the sky. It looked brighter than Venus. After a couple minutes we realized it was moving ...
2
votes
1answer
79 views

Simple mathematical models of solar systems

I’m a hobbyist programmer with a profound love for procedural content generation. I’m working on a 2D space exploration game and while it’s not meant to simulate anything real, I’d like to give it a ...
1
vote
2answers
81 views

Can a planet's gravity rip out its moon's atmosphere?

We all know that solar flares can rip a planet's atmosphere if the magnetic field is weak.Solar flares travel at tremendous speed so when they hit the gas molecules of a atmosphere the molecules are ...
7
votes
3answers
77 views

Is Mars brightest from Earth at opposition, perihelion or somewhere in between?

After reading this article, I was inspired to run some simulations at NASA's JPL Solar System Simulator to see Earth's and Mars' orbits from above. From what I could visually determine (from the JPEG ...
1
vote
1answer
75 views

Are large body orbits self correcting?

If a rogue planet disrupts Earth's orbit slightly to cause a long winter or summer will the Earth's orbit normalize back close its original orbit over time? Could a Planet X or some other elliptical ...
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votes
1answer
66 views

Where will the atmosphere of our Earth go if our sun blows it away completely?

What will happen?Will our atmosphere head to the next gravity dominant body?Will our moon hold a part of our atmosphere or is too weak to hold it?Where all those gases are supposed to go?
7
votes
1answer
143 views

Saturn's tropical year?

What is the value of Saturn's "tropical year" (as opposed to its "sidereal year"). I am seeing it listed as 10 days shorter (10,747 days) than the sidereal year (10,759.22 days). How could this be ...
6
votes
2answers
115 views

Why does each and every planet of our solar system have an unique axial tilt angle?

Why do planets have an axial tilt? From the above image we can see that each planet's axial tilt angle varies and differs from the others. What was the cause of this, was this from the beginning of ...
0
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2answers
146 views

Could planets explode in space?

Could a planet like the Earth or any other explode or be destroyed and did we see a planet explosion with Hubble?
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vote
1answer
83 views

Where do gas giants end up?

I want to create a semi realistic star system generator but I am not sure where to "put in" gas giants. My guess is they can form pretty much anywhere within the sphere of influence of a star at the ...
3
votes
1answer
102 views

Why planets and stars are always round/oval in size? [duplicate]

What kind of stability it provides to each and every celestial body that each one them are round in shape?
4
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1answer
54 views

Is there any difference among exoplanets in composition due to host star?

Simply put, would, say, rocky planets orbiting red dwarfs have a noticably different chemical makeup than rocky planets orbiting B-type main sequence stars? Mutatis mutandis gas giants and the other ...
4
votes
1answer
78 views

Is the age of the solar system equal to the age of meteorites?

I've read articles that state the age of the solar system has been determined by measuring the amount of decay of isotopes in some meteorite, which has demonstrated that the lead isotopes in the ...
5
votes
2answers
236 views

Trisolar syzygy and it's effects on the planet

Slightly spoilers here, but in the novel The Three-Body Problem, there's a scene in which Civilization #184 is destroyed by the stacked gravitational attraction of the planet's (aptly named Trisolaris)...
0
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1answer
97 views

what should be the minimum magnification of the telescope to see properly the cloud(red spot) of jupiter? [duplicate]

and what should be the minimum focal length of objective lens and focal lens. I've a celestron which have 300mm focal length of objective lens and 6/4/12/20 mm of eye piece but it's hard for me too ...
2
votes
1answer
26 views

Scattered Intensity of Light vs Angles of Incidence and Emission

So I just derived an expression for the scattered intensity of light from an atmosphere with ideal isotopic scattering: $I/F=\frac{cos(i)}{4(cos(e)+cos(i))}$, where $I$ is intensity, $F$ is flux, $i$ ...
4
votes
2answers
365 views

Detecting habitable planets

From my understanding we detect planets by measuring dips in light intensity from the star the habitable planet is orbiting when it passes by it. There are 2 things I don’t understand about this ...
1
vote
1answer
45 views

Longitude of Perihelion at J2000?

My textbook (and lots of other sources) shows the earth's longitude of perihelion at the epoch around 103 degrees. I understand that this means (in the neighborhood of J2000) the earth will reach ...
0
votes
3answers
65 views

Impact of inclined orbit satellite on a planet

If a satellite in an inclined orbit breaks up in orbit and multiple fragments hit a planet, do the individual fragments follow 1 a sinusoidal path 2 a geodesic ( or great circle curve) 3 a straight ...
4
votes
1answer
70 views

How would one calculate the synodic period between 3 planets?

I don't know if this is the correct term, but how would one calculate the time it takes for 3 planets to lie on the same line?
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vote
1answer
61 views

What am I looking at?

I am in Northampton England and every night in the SW sky is a very bright, white light that twinkles. It visibly appears to be moving towards the west but appears pretty much the same start place ...
2
votes
1answer
55 views

Do the number of moons a planet has affect the speed of the planet's rotation?

Would the tidal forces of multiple moons interacting upon a planet speed up or slow down the day length of the planet? I was thinking that maybe the planet's day length would be slowed down due to all ...
5
votes
1answer
149 views

Is it likely that intergalactic stars would still retain their planets?

Given that we've discovered hundreds of intergalactic stars (IGs), and that most stars have planets, what do we know about the likelihood of IGs retaining their planets after being ejected from their ...
1
vote
2answers
98 views

Is Venus visible throughout the night?

I know that Venus is visible during sunset and sunrise, but is it also visible in deep dark night?
0
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1answer
86 views

2002 Planetary alignement

In april 2002 the inner planets had aligned and this event was captured in this beautiful photo: But, according to this website simulations for the date, Jupiter was pretty much away. Is that ...
2
votes
2answers
103 views

Are all impact craters circular?

I'm aware for over 100 years the reason has been known how impact craters are almost always circular, but my question really is has there been any recent insights in the area? What other topologies ...
1
vote
2answers
119 views

Why are the planets moving? [duplicate]

My question isn't why it doesn't have a circular orbit, and why an elliptical, my question is why do they move at all? What caused the debris in space to apply such a force on the planets that it has ...
0
votes
2answers
113 views

Do other planets affect the Earth?

Let say Mercury, Venus, the Moon were all in alignment between the Earth and Sun. They are all closest to each other in respective elliptical orbit. On the other side of the Sun you have the rest of ...
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vote
5answers
178 views

Why is sun's photosphere a million times less dense than air at the surface of the Earth?

Sun's photosphere is about 19 times as hot as Earth's surface. (Source: http://solar-center.stanford.edu/vitalstats.html) But Solar surface gravity is about 28 times terrestrial surface gravity. So,...
2
votes
1answer
168 views

Would a spacecraft just go “through” a gas giant?

From my understanding of the word gas giant, it is a planet composed of entirely a gaseous atmosphere, and so planets Jupiter and onwards fall in this category. That being said, what would stop a ...
1
vote
1answer
50 views

How would you relate the respective solar gravitational pulls of two planets?

I was asked this question: How much weaker is the gravitational pull of the Sun on Neptune at 30 AU, than it is on Earth at 1 AU? How would I even begin to determine this?
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2answers
72 views

Would you expect this planet to be hotter or colder than earth?

I have a lab where given the mass of a star being $1.23$ times the math of our sun, some planets wobble of central start is $273$ days, and the velocity of 79 m/s. I found that the mass of the planet ...
2
votes
1answer
100 views

How big are the rocky/icy cores of Jovian planets?

The size of Earth? Or bigger? I'd think they'd have to be pretty big to attract all that gas when the planets were being formed. edit I'm writing a short story and the setting consists of late ...
3
votes
1answer
108 views

Jupiter vs brown dwarf star

What would happen to Jupiter if a brown dwarf star collided with it, and vice versa what would happen to the brown dwarf star?
3
votes
2answers
114 views

Do unattached objects contribute to a planet's gravity?

If you could measure Earth's gravity with infinite precision, and did so both with Earth and its full population, and Earth with no people, would there be a direct difference in gravity? Is this even ...
0
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1answer
60 views

Distance from the sun can equal a hospitable planet?

It is said that planets are continuously moving away from the sun. At one time Mars was just the right distance to support life at least temperature wise? Could Venus be far enough from the sun ...
3
votes
1answer
61 views

What is the official term for a relationship between a planet and its moons?

Sorry if this is a dumb question, I could not find anything naming this in my astronomy books, and Google searches only seemed to show me pages about astrology, [sarc] because naturally, human ...