All Questions
Tagged with exoplanet or exoplanets
122 questions
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How is global warming distributed with respect to altitude?
Lets assume a sea level temperature increase 2c/3c. Then, what is the temperature increase at 10 km altitude? Temperature increase at 30 km altitude? Temperature increase at 70 km altitude? And ...
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What orbit does a planet have to have to be a planet? [closed]
Other questions have dealt with where you could find a planet-like object, and what a planet has to consist of to count as a planet. But this question is directed as what orbit or path an object would ...
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Finding distance Range for an Exoplanet to be detectable
I have been trying to solve the following problem, I found while reading some Exoplanet detection techniques, namely, radial velocity method and Astrometry.
Problem statement:
"
Imagine yourself ...
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Rayleigh Scattering and Red Giants
Rayleigh scattering is responsible for the color of the sky. Consider a planet with an atmospheric composition similar to Earth's but orbiting a red giant. Suppose further that the planet is in the ...
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Why is Mars so cold when it has so much atmospheric $CO_2$?
Mars has 1/10 of Earth's atmosphere but that atmosphere is 95% CO2. Why is Mars so cold when it has so much atmospheric CO2?
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Non-discoveries by the Kepler space telescope: exomoons, co-orbital planets, trojans
I am just reading the review article Advances in exoplanet science from Kepler (arxiv preprint: http://arxiv.org/abs/1409.1595), and I found a remarkable paragraph (last paragraph in section "...
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How does TESS focus on bright nearby stars?
How does the Transiting Exoplanet Survey Satellite "focus on" bright nearby stars, in contrast to the Kepler Mission's focus on dim distant stars?
I understand that the fields of view of the two ...
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2
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Doppler method for detecting exoplanets
Why does the Doppler method for detecting exoplanets only give the minimum mass for the exoplanet and not the actual mass?
Is it to do with whether the exoplanet is a face on orbit or a side on ...
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Why does a starshade have to be put so far away from the telescope?
I understand why starshades have the shape they do, but i don't seem to understand why they have to be put so far away from the telescope. Why can't we keep the same apodization function, but just ...
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2
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Sodium sometimes absorbs orange-yellow light, sometimes emits it? Huh?
Usually, we are told that sodium emits orangish-yellowish light, which is why city streetlamps are that color.
Now, I read in New Scientist magazine that exoplanet WASP-96b is bluish because the ...
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Do any naked-eye stars have planets
Are there any known exoplanets around naked-eye stars? I know that Fomalhaut has a planet, and Vega has a dust belt that may be a protoplanetary disk or even analogous to our Kuiper belt. What else is ...
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Have scientists thought about these two questions? [closed]
I would like to know if our vision bends with the earth or if the earth truly is round. If I look through a strong enough telescope to see around the world, would I be able to see the back of my head? ...
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What is the percentage of stars with planetary systems
We have discovered quite a number of exoplanets to date. The Kepler spacecraft has examined 150,000 stars and found 1,059 exoplanets.
We know that Kepler, as well as all other exoplanet searches to ...
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Gas giant evolution over lifetime
In various types of stars, one can learn how they evolve differently, depending on factors such as their size and chemistry. Some stars have a short lifetime and others much longer.
But, what is ...
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are alignment of star systems' orbital planes with ours better than random?
It obviously helps our observation of exoplanets if they transit their star from our point-of-view. I would guess that the chances of this alignment are better than if their orbital plane was randomly ...
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Fusion inside a planet with high concentration of radioactive elements?
If an Earth-sized or larger planet had sufficiently large amounts of radium, thorium or uranium, couldn't the resulting fission trigger periodic fusion of hydrogen? I'm thinking of fission happening ...
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Why do we refer to life on Earth when we talk about life on other planets? [closed]
I have always had thoughts about extraterrestrial life and I wonder why researchers largely compare the conditions for existence of life to that on the Earth?
Is it impossible that on a remote ...
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In searching for an exoplanet by observing transitions, isn't it rather rare that an orbital plane would line up with Earth?
Given that we are at a random orientation to any remote star system, it seems to me that there is only a narrow angle at which transits of exoplanets can be observed.
Imagine a large mathematical ...
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Planets capable of life: dead or still alive?
There are some planets that scientists speculate may be capable of supporting life. However, these planets are hundreds of light years away. How can we be sure they are still capable of supporting ...
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Exoplanet detection via space-based parasol
I remember from watching Cosmos years ago, Carl Sagan suggested an interesting hypothetical method for directly seeing exoplanets. He proposed that in the 'future' we could launch a satellite designed ...
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Do stars of higher metallicity have more planets in highly-inclined Pluto-like orbits?
In an answer to a previous question of mine, one that asked about the planar orbits of inner planets, I was told the following (emphasis mine):
On the subject of different solar systems, I would ...
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2
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Why did population III stars lack planets?
Jay Wacker1 (professor of physics at the SLAC National Accelerator Laboratory) stated:
The first stars (known as Pop III) were made out of hydrogen and helium. They had no planets.
Why couldn't ...
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What is the unit of time "JD" in an astronomical context?
For my high school physics project I am required to research a planetary system. The orbital period of the planets are given in JD. What are these units? I've tried to research it, and I've found it ...
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Toroidal planetary systems
Is it possible that two toroidal, rigid, homogeneous planets are forming a system in which the toroids are chained through each other, and during their mutual motion, the planets are never touching ...
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Where to start, if I would like to run a planet climate simulation? [closed]
I would like to understand the math behind it, and maybe write an own climate simulator program. I know, that it is a really hard subject. But I'm curious, and I would like to learn more about it. But ...
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Is it possible to get to get to Proxima B in 30 years?
This morning I read about the discovery of an earth-like planet, Proxima B, being 'just' 4.22 light years away from us. This is quite interesting since the planet is oribiting our closest neighbour.
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Locating a possible habitable zone in an ordered hierarchal septenary star system?
I'm writing a story about potential off-world colonization in the dawn of interstellar commerce, and despite such a plot necessitating some degree of FTL travel I'd like to keep the rest of my science ...
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What is the farthest planetary body or star system object we have observed using visual light?
What is the farthest object which we can get a direct Detailed visual image of using visible light which appears more than just a dot and falls into one of the following categories:
Planet
Satellite
...
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What is the difference between habitable and Goldilocks zone?
If I am right, Habitable Zone means that a planet is on such a distance from its Star which makes it good candidate for supporting some sort of life.
But then what is Goldilocks zone and how is it ...
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How does a planet's size really affect its surface gravity?
If we located an exoplanet whose diameter was $x$ times that of the Earth's in size, and which for simplicity appeared to have an identical composition to that of Earth, then its mass might be taken ...
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How is the stellar flux for exoplanets calculated?
I have noticed that in many Wikipedia articles, the stellar flux received by each planet is stated. I tried to calculate this stellar flux from the given data, but the results didn't seem to be ...
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Finding radius of an exoplanet's orbit knowing orbital period and star's mass [closed]
I've been stuck on this question in an assignment for a while now, and I can't seem to find anything on the internet that either deals with a question in which more values are provided, or where the ...
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Have we observed sufficient extra-solar planetary systems to establish a planetary distribution pattern? [duplicate]
From Kepler And Extra-Solar Planetary Observations
As of January 2015, Kepler and its follow-up observations had found 1,013 confirmed exoplanets in about 440 stellar systems, along with a further ...
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Are there rogue planets between Sun and Proxima Centauri?
Would we be able to detect (via emitted radiation, or its gravity) a rogue planet between us and Proxima Centauri? How big would that planet need to be?
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Calculating eccentric anomaly using the Newton-Raphson method
Yesterday I asked a question on calculating the eccentricity of an exoplanet only knowing the radial velocity vs. phase graph an the mass of the star (question). The answer I got helped me a lot, but ...
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If a hot Jupiter was not tidally locked, then are there any specific cases where its wind speeds would be milder than those found on Jupiter?
If a hot Jupiter was not tidally locked, are there any specific cases where its wind speeds would be milder than those found on Jupiter?
After controlling for the age of the hot Jupiter, of course. ...
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How can a gas giant be about the same size but six times more massive than Jupiter?
I've just read this article: http://www.sci-news.com/astronomy/science-kepler-432b-new-super-jupiter-exoplanet-02490.html
And I wondered how this could be possible?
Maybe it's because this gas giant ...
- 213k
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Calculating the size of exoplanets with moons
When astronomers detect an exoplanet using its transit and calculate its size to be, say twice the earths size, do they have any way of knowing that its actually not a slightly smaller planet with a ...
- 137k
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Exoplanet Mass-Radius Diagram
I'm currently studying the following diagram:
But I'm not entirely sure I understand what's going on. Is it just, that most exoplanets discovered, is pretty much made up of Hydrogen and Helium ? And ...
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Density of a planet
I was wondering, how would you find out about the mass and the density of a planet and what the planet is made of?
Finding out about the mass might be possible, because you can observe the movements ...
- 137k
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2
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297
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Habitable zones around other stars
I have a question about measuring the boundaries of habitable zones on other planets.
Is it okay to assume that, if Sun's habitable zone starts at a distance $R_0$ and its luminosity is $L_0$, we can ...
- 137k
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What would we see if we looked at our Solar system from 2,000 light years away with our current technology?
Assuming the tables were turned and we would live in a system like Kepler-422/423/424, some 2,000 ly away. If we'd look at the Solar system with a telescope like Kepler and using techniques like ...
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Multiple planets orbiting a star
One way of detecting exoplanets orbiting around a star is the Radial velocity method.
Can this be used to detect multiple planets? Wouldn't the star orbit the center of mass of the whole system with ...
- 137k
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For a planet which has a temperature gradient, hot in the center and cooler on the surface, why do we get absorption lines?
For a planet which has a temperature gradient, hot in the center and cooler on the surface, why do we see absorption lines?
Similarly, why do we see emission lines if the planet is hot on the ...
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Spectroscopy and the current state of our ability to determine the composition of extra-solar planets
I was interested in learning more about the status of our scientific understanding and technological instruments regarding extra solar spectroscopy.
I am motivated by this almost 3 year old question/...
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Is there a simple formula for calculating semimajor axis bounds of "habitable zone"?
I understand that an accurate determination of the bounds of the "habitable zone" for a given stellar system depends on a large number of factors, including many beyond characteristics of the parent ...
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how find resonance in extrasolar planet? [closed]
I make this program, i have a 2xN matrix in which the columns are the ID of planets and their period, the rows are the number of planets, for istance something like that:
...
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Are the known exoplanets representative of the population of exoplanets?
An article about the recent release of a large number of confirmed exoplanets states that most of the 715 newly announced exoplanets orbit very close to their host stars.
Do the theories predict ...
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Is there any other solar system in the universe?
Is there any other solar system far away from ours in the universe?
Why don't we expect another solar system based on another star similar to sun in the universe?
If so, Why probably there wouldn't ...
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510
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Earliest terrestrial planet?
If I've understood correctly, the heavier elements needed for terrestrial planets such as iron can only form in supernova.
If that is indeed true, how long since the beginning of the universe would ...
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