Earth is only a minor planet, the bigger ones like Jupiter and Saturn have more.
Earth is only a minor planet, the bigger ones like Jupiter and Saturn have more.
The possibility of water on Mars' surface has been questioned. See the post below: http://www.space.com/35071-mars-dark...er-debate.html
More on Trojans: EarthSky report that a probe will search for more. See http://earthsky.org/space/osiris-rex...ojan-asteroids
I can see how more massive planets would have more trojans.
Thats what I said. What about the other questions?
It easier if you quote the post you are addressing...
I am just agree with you. I am glad to see the OSIRIS_REx spacecraft can get a closer look.
So Lagrangian points 1,2 and 3, all in one straight line with sun and earth, are barely stable, and points 4 and 5, 60° ahead of us and behind us in our orbital path, are highly stable. We have a cool one and a hot one a million miles on either side of us directly in line with us and the sun which are barely stable. Not much use is projected for point 3 on the far side of the sun, where the legendary (fictional) planet X is supposed to be. If there were a planet our size there, they would probably reason that any planet in our position would have an unstable orbit, so there is probably not one where we are. Ahem!Originally Posted by Dreamwoven
At least points 1 and 2 are stable enough for space equipment to reside. At point 2 no special cooling equipment is required, which simplifies a mission. Points 4 and 5 are great prospects for some asteroids we can mine or for settlement. Any news of those locations will be of keen interest to any who read this thread.
Which brings me to a question: If these are the famous Lagrangian points and the nearest are a million miles away, what are these stable points that Arthur C. Clarke was responsible for predicting where we now keep many satellites parked? Are these too Lagrangian points, but points from a separate deal between the earth and moon? These points are only about 22000--26000 miles from earth, I believe. These points seem to represent "gravity wells," as well, just like their bigger brothers, if that is even what they are. Do you know anything about that?
Last edited by desiresjab; 12-23-2016 at 03:34 AM.
I answered my own question. They seem mechanically separate phenomena, though they could be confused as related. An object in obit around earth at a Clarke point travels around us at the same rate we rotate on our own axis. The net result is it stays in one place above a point on the equator through night and day with us. If Clarke points and Lagrangian points have a relationship, I do not see it. I know almost no mathematics of celestial mechanics, so there could easily be a relationship I do not see.
Hmm, my understanding of Lagrangian Points is that they exist between all planets, suns, and any space object that has its own gravity. I don't know anything about Clarke Points as mathematical phenomena, though.
Hmm, my understanding of Lagrangian Points is that they exist between all planets, suns, and any space object that has its own gravity.
I can't find anything helpful on Clarke points. Only this website in Wikipedia but in Swedish on Clarke Points: https://sv.wikipedia.org/wiki/Clarke_Point
http://www.universetoday.com/132413/...saturns-moons/
Extracts from this post. read the whole article at the above link.
Welcome back to our series on Colonizing the Solar System! Today, we take a look at the largest of Saturn’s Moons – Titan, Rhea, Iapetus, Dione, Tethys, Enceladus, and Mimas.
From the 17th century onward, astronomers made some profound discoveries around the planet Saturn, which they believed was the most distant planet of the Solar System at the time. Christiaan Huygens and Giovanni Domenico Cassini were the first, spotting the largest moons of Saturn – Titan, Tethys, Dione, Rhea and Iapetus. More discoveries followed; and today, what we recognized as the Saturn system includes 62 confirmed satellites.
What we know of this system has grown considerably in recent decades, thanks to missions like Voyager and Cassini. And with this knowledge has come multiple proposals that claim how Saturn’s moons should someday be colonized. In addition to boasting the only body other than Earth to have a dense atmosphere, there are also abundant resources in this system that could be harnessed.
Much like the idea of colonizing the Moon, Mars, the moons of Jupiter, and other bodies in the Solar System, the idea of establishing colonies on Saturn’s moons has been explored extensively in science fiction. At the same time, scientific proposals have been made that emphasize how colonies would benefit humanity, allowing us to mount missions deeper into space and ushering in an age of abundance!
On March 9th, 2006, NASA’s Cassini space probe found possible evidence of liquid water on Enceladus, which was confirmed by NASA in 2014. According to data derived from the probe, this water emerges from jets around Enceladus’ southern pole, and is no more than tens of meters below the surface in certain locations. This would would make collecting water considerably easier than on a moon like Europa, where the ice sheet is several km thick.
Data obtained by Cassini also pointed towards the presence of volatile and organic molecules. And Enceladus also has a higher density than many of Saturn’s moons, which indicates that it has a larger average silicate core. All of these resources would prove very useful for the sake of constructing a colony and providing basic operations.
In October of 2012, Elon Musk unveiled his concept for an Mars Colonial Transporter (MCT), which was central to his long-term goal of colonizing Mars. At the time, Musk stated that the first unmanned flight of the Mars transport spacecraft would take place in 2022, followed by the first manned MCT mission departing in 2024.
In September 2016, during the 2016 International Astronautical Congress, Musk revealed further details of his plan, which included the design for an Interplanetary Transport System (ITS) and estimated costs. This system, which was originally intended to transport settlers to Mars, had evolved in its role to transport human beings to more distant locations in the Solar System – which could include the Jovian and Cronian moons.
Last edited by Dreamwoven; 12-23-2016 at 10:51 AM.
As far as colonizing those places go, it seems more useful to put satellites around them or send probes to their surfaces. They could be our eyes. I suspect mining could have some value if there is something there that we need on Earth.
It was interesting reading about setting up a greenhouse effect on Mars to warm it up so it would be more habitable for us to get there, however, controlling the greenhouse effect on any planet including our own might be useful for those planets already in the habitable zone. If we can terraform Mars we should be able to terraform Venus and have the technology to make sure Earth stays terraformed when it gets closer to the Sun. I think the best solution would be a set of satellites that reflected away radiation from the Sun or focused it depending on the degree of greenhouse effect we wanted to achieve. We should experiment with the Moon first.
Absolutely Lagrange points exist around all massive objects. Here is the other point that Clarke first suggested. They are known as geostationary orbits. They are a different phenomenon from the Lagrange points because they stay with a single point on our equator as that point moves through night and day, while the Lagrange points are stationary (except for moving with us in orbit) and all points of our equator pass beneath them (assuming, that is, that they are aligned with our equator, which I do not know for sure).
As I think about it, I am starting to believe the Lagrange points would not be oriented above our equator at all, but about the Great Circle (a mapping term) which would be our equator without tilt. It is an interesting question which I have to find out though I am now pretty sure the Lagrange points would care nothing at all for our equator, any more than they would align themselves with some of the highly eccentric planetary orbits found in our solar system. Our home pair are a million miles away. No, they would not care about our little equator. Sometimes you answer your own questions.
So Lagrange Points would be the best places to locate space telescopes, like Hubble and Spitzer. Makes sense!
About the "warm Neptun", a new planet:
"A pioneering new study uncovering the 'primitive atmosphere' surrounding a distant world could provide a pivotal breakthrough in the search to how planets form and develop in far-flung galaxies.
[/I]The atmosphere of the distant “warm Neptune” HAT-P-26b, illustrated here, is unexpectedly primitive, composed primarily of hydrogen and helium. By combining observations from NASA’s Hubble and Spitzer space telescopes, researchers determined that, unlike Neptune and Uranus, the exoplanet has relatively low metallicity, an indication of the how rich the planet is in all elements heavier than hydrogen and helium.[/I]
Credit: NASA/GSFC
At:https://www.sciencedaily.com/release...0511141951.htm
Last edited by Danik 2016; 05-17-2017 at 12:32 PM.
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