Questions tagged [exoplanets]
Exoplanets (also known as Exosolar or Extrasolar planets) are planets outside the solar system.
90
questions
0
votes
2answers
44 views
Formation of Life on various planets
Is there any theory that suggests every creature (including bacteria and fungi) in our planet is formed by the atoms of our planet. If that is true, then is it possible that any other organisms will ...
0
votes
0answers
17 views
Will it be possible to remotely determine the vertical temperature/pressure profile of an extrasolar atmosphere?
I was wondering why this equation seemed to work, but I guess no one has a good explanation so it is assumed to be a coincidence for now. Unfortunately, it could only be expected to work for "earth-...
1
vote
2answers
73 views
How do astronomers measure the mass of a planet using Doppler spectroscopy?
So, I am making an essay explaining planet-hunting techniques. And while I do get how astronomers measure the semi-major axis of a planetary orbit (using Kepler Laws), I don't get how they measure the ...
0
votes
1answer
45 views
Why is relativistic beaming/ Doppler beaming occur at non-relativistic speeds
The reflexive motion of a binary star system causes the host star to occasionally wobble towards and away from an observer on Earth, which gives rise to an effect called relativistic beaming. This is ...
1
vote
1answer
36 views
Can a planemo turn into a star?
I read this question
Why is planet CFBDSIR2149-0403 hot?
and wonder what will happen to this "planemo". Will it attract more mass as it flows around in the gas clouds in space and eventually light ...
2
votes
0answers
98 views
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 ...
1
vote
2answers
112 views
On Planets orbiting binary stars
Several years ago a discovery was made of planet orbiting a star of a binary system (two stars orbiting each other). Since binary star systems are plentiful in our galaxy, I presume we will be ...
0
votes
0answers
31 views
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 ...
0
votes
1answer
47 views
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 ...
0
votes
3answers
169 views
Why do gas giants have similarly coloured stripes?
After looking at Jupiter and searching 'exoplanets gas giants' on google I found that many had stripes on them. I found that pretty peculiar. So why do they have stripes. I think it has something to ...
-3
votes
3answers
751 views
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?
-3
votes
1answer
182 views
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 ...
1
vote
1answer
41 views
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 ...
2
votes
1answer
49 views
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 ...
1
vote
0answers
52 views
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 ...
4
votes
2answers
250 views
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 ...
-3
votes
1answer
123 views
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? ...
5
votes
0answers
89 views
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 ...
-4
votes
1answer
105 views
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 ...
0
votes
2answers
106 views
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 ...
0
votes
1answer
85 views
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 ...
1
vote
2answers
816 views
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 ...
0
votes
0answers
26 views
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 ...
0
votes
1answer
504 views
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 ...
20
votes
1answer
1k views
Can we know if an exoplanet has a magnetic field?
The recent discovery of the exoplanet Proxima b gave rise to several questions concerning its habitability and its potential to host life. A major concern is the huge amount of radiation coming from ...
4
votes
2answers
138 views
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.
...
1
vote
2answers
331 views
Is there an equation that can estimate chances of alien life in the universe?
Seeing how infinite the universe appears and out of all of those stars, planets, galaxies, there must be other life forms. Mathematically, the odds are very good. Is there a mathematical equation to ...
1
vote
0answers
77 views
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 ...
15
votes
2answers
2k views
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
...
0
votes
1answer
214 views
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 ...
2
votes
1answer
189 views
Simulation of relativistic probe passing through an external solar system
I recently read about the Breakthrough Initiative to launch "StarShot", a nano-probe that is designed to travel to Alpha Centauri at $0.2c$. One of the challenges to be solved involves the precise ...
2
votes
1answer
1k views
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 ...
77
votes
6answers
8k views
How can we see planets thousands of light years away but don't know if there are more planets in the solar system?
That is basically my question, it arose when I saw an article (here is the scientific paper, which should be free to read) saying two Caltech scientists might have found the 9th planet of the solar ...
2
votes
1answer
986 views
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 ...
4
votes
2answers
805 views
How does rogue planet PSO J318.5-22 stay 800ºC?
According to this article, the rogue planet (meaning a planet which does not orbit a star) PSO J318.5-22 has a surface temperature of 800ºC and weather that features molten iron rain. Without a star ...
3
votes
1answer
83 views
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 ...
3
votes
2answers
745 views
Lift and drag coefficients on other planets
The question I'm trying to answer seemed simple: how hard would it be to fly on a planet with lower gravity but also thinner atmosphere compared to Earth. If the answer could hint me at how much ...
0
votes
0answers
35 views
How do exoplanet surveys precisely measure stellar properties?
All measurements in exoplanetary studies (e.g. the Kepler study) depend on how precisely we know the properties of a star. For instance, the planet mass and radius is known only as well as the star's ...
2
votes
2answers
12k views
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 ...
10
votes
2answers
2k views
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 ...
0
votes
1answer
967 views
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 ...
2
votes
1answer
117 views
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 ...
2
votes
1answer
2k views
Calculating the eccentricity of an exoplanet
I'm wondering how to calculate the eccentricity of an exoplanet by its radial velocity vs. phase graph. To clarify my question I will take an exoplanet called WASP-14b 2 as an example (http://...
3
votes
1answer
403 views
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 ...
2
votes
1answer
403 views
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 ...
2
votes
2answers
259 views
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 ...
2
votes
0answers
97 views
Global Circulation Model of tidally locked planets for PC?
Is there some free simple Global Circulation Model that can handle tidally locked planets and can be easily compiled and used on a PC computer? It does not have to be very precise, I am interested ...
13
votes
2answers
1k views
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 ...
1
vote
1answer
128 views
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 "...
1
vote
1answer
138 views
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 ...
