As Uranus speeds in its orbit in the solar system, there are three large space rocks that are in lockstep with the gas giant, according to new simulations. Two of them are wobbling in unstable “horseshoe” orbits near Uranus, while the third is in a more reliable Trojan orbit that is always 60 degrees in front of the planet.
The largest of this small group is the asteroid Crantor, which is 44 miles (70 kilometers) wide. Its horseshoe orbit, and that of companion 2010 EU65, means the space rocks seesaw between being close to Uranus and further away. They should stay in that configuration for a few million years.
The last of the group is 2011 QF99, in a Trojan orbit near one of Uranus’ Lagrangian points — sort of like a celestial parking spot where an object can hang out without undue influence from the balanced gravitational forces.
The results illustrate the importance of space rocks that are outside of the main asteroid belt between Mars and Jupiter.
There are several kinds of these asteroids (classified by their orbits) that follow around planets in the solar system. Earth itself, for example, has at least one Trojan asteroid.
“Crantor currently moves inside Uranus’ co-orbital region on a complex horseshoe orbit. The motion of this object
is primarily driven by the influence of the Sun and Uranus, although Saturn plays a significant role in destabilizing its orbit,” the authors wrote in their new study.
“Although this object follows a temporary horseshoe orbit, more stable trajectories are possible and we present 2010 EU65 as a long-term horseshoe librator candidate in urgent need of follow-up observations.”
The results are described in Crantor, a short-lived horseshoe companion to Uranus (Astronomy & Astrophysics, March 3, 2013.)
How the heck do you find something this small, so far away??? Unfortunately, I don’t have access to the original journal article to find out.
Crantor – sounds like something that would attack a Japanese city in a b movie. I love it.
Looks like Crantor was found back in the early 2000’s by a variety of telescopes, initially by the near Earth asteroid people, then found in many other telescope images. It is very red and a fair bit has been known about it for a while. There’s a lot of interesting information about the object in the paper, very little of which is included in this UT article.
If Uranus does not have a clear orbit doesn’t that bring in to question whether or not it is a planet? Isn’t it a requirement of a planet to clear it’s orbit?
The criterion “cleared the neighbourhood around its orbit” for the definition of a planet means that it is the gravitationally dominant body in its orbit.
Could it be our moon was captured by earth? Of course a perfect angle and trajectory would have to of been perfect to accomplish this possibility. The moon is huge in comparison to our earth. The now theory accepted a Mars size planet ramming into earth and the many fragments big and small coalesced into our moon to me is a bit much. But like earth capturing our moon. All possibilities are possible. The more questions we ask. The more questions arise. Amazing how Hubble and alike can see these objects billions of miles away. You scientists and engineers who conceive are just “bad-to-the-bone”.
There are three ways a planet can capture a “satelite”,
1) degredation from horseshoe orbit to normal orbit, The minimum distance for this lies beyond the Moon.
2) Collision debris
3) Capturing a binary “satelite” of which one part will be flung back into space and probably out of the solarsystem and the other part becomes a satelite
Of the three options, our moon was born out of option number 2,
Beter knowledgeble people can correct me, as i’m mostly a layman.
Hows the weather up there in Holland Zou? I have always wanted to go there since I was a teenager. Israel and Australia too. Here on the north east coast of the US the weather is great! Sunny and 82 degrees at 12pm.
Anyways, .the 1 2, and 3 theories I have read about. Whats to say there is not a 4, 5 and 6? Who is to say the trajectory, speed, angle was so perfect, our earth just grabbed the moon from its orbit? There are so many possibilities. Take the theory only the sun can support life. WRONG! 10 years ago or so Thermal vents on the sea floor blew that theory “out-of-the-salt water”. ..no pun intended ;-).
Hi Planemo, weather is great, especially with the continental summer air expanding it pushes the wet sea air outward, until the air pressure drops again with Authum bringing lots of rain. No doubt farmers will tend to disagree with me. But that aside.
As space is empty any trajectory at any angle will always be a parabola, unless there is a bleed off of its speed, this will always hold true. Not even the natural gravitional tidal waves that ever so slightly shifts orbits will have no effect on this, as the effect needs to have a lot of effect on a short trajectory, which would need to be in the vicinity of Earth itself and would need to be MUCH larger than pulling the emergency break on a train.
And the only thing that can accomplish such a force over such a short time would be called a collision.
Hopes this helps to understand that just as Live needs energy to thrive, so does orbit shifts require energy to shift.
Cheers
Hello! Yes, I have heard of the northern latitudes huge high pressure systems bringing in the fresh sea air and summer warmth to your region. I am very near Cape Cod. We get local seas breezes which cools the hot summer sun. It even squashes thunderstorms like is happening right now.
Yes, I agree with all you said about orbits and the gravitational pull needed, and the bleed off in speed etc.. . . I have read a lot of other writings also. A few think the way I do with capture. All I am saying is, “what if everything came together perfectly”? Trajectory, a speed bleed off, angle and all the etc’s.. .It would have to be just short of a full collision. I appreciate your comments and the matter of facts you typed. I am a total “what if” kind of guy and lets check if could be possible.. The fact earth is not big enough to capture the moon with its small gravity is the only fly in the ointment. It is just a thought and a faint possibility. Nothing about how the moon got here has been set in concrete fact yet. How about you and I build a “time-machine” and go back 4 billion years and watch what happens.. I’ll drive your ride shot-gun ok?…lol. Cheers back at ya 😉
Dont the hydrogen isotopes identify bodies uniquely?and the earths and the moons are the same
Yes, I agree, but up to a point. Are we not in the same solar system? Are we from the same ‘super-nova’ debris which spawned our sun and all the gas giants, rocky planets to the asteroids? Doesn’t the Oort cloud contain trillions of comets with hydrogen isotopes in them? Just a thought and possibilities. 😉
Fair enough, the research on hydrogen isotypes is still ongoing and there’s a lot of possibilities.
And we should be from the same debris, however the time of planet formation wasnt identical and hopefully that will come forward from the ongoing research 🙂 But its way to soon to decide which theory is fact.
I like you 😉 – Excellent. You have an “open-mind”. That was perfectly said by you with “Fair enough”. Heck, we have barely stepped inside our solar system never mind outside of it.(Oort cloud area etc). We now have some knowledge what comets are from ‘probes’. We have way, way, way.much more to learn. Heck, we are clueless figuring out how did all this H2O get here on our earth, never mind how the moon was formed. Was the moon coalesced from a Mars size like object.impact? Sounds good, but to me there’s many other possibilities how. We will find the facts someday.
Do you know what I wish for the most? I want to be alive to see the days of Star Trek! Warp drive! Now you see me, now you don’t….lol. Having breakfast on the Pluto outpost, and supper in Boston. TOO KOOL! 😉
Haha thanks, im always interested in science and last few years mostly astronomy. Where you need an open mind, because as you say, we have just begun exploring beyond our own planet and only got of our planet since the 60s and have yet to go beyond the moon, which is just a stonesthrow away. Im also hoping until the moment we build our own enterprise and hope we can bend time and space so we can go beyond light speed.
so much to see, so much to learn, so much to explore.
we might be alone in the universe, or we aren’t, each is equally horrifying and interesting. All we know that in a ~80 light year radius around us there is most likely no highly advanced civilization or that we are of no importance to them.
we should just not forget for now almost everything is theory and not yet fact, many people,forget that 🙂
I believe given the mass of the Moon vs the mass of Earth the only way it could have wound up where is now would be as a result of collision.
If you gave it enough passes I guess that could work as well, however the moon would have had to have been a really elliptical orbit. If its orbit was that far from circular I’d wager that Jupiter’s gravity would prevent it from making enough passes at just the right trajectory for earth to capture it and have it wind up in the neat and tidy orbit we find it in today.
I agree with you. The possibilities are there. Yes, depending on the moons orbit trajectory, speed, etc’s., yes. I think Jupiter is key also.
Take all H2O on this planet. How did it get here in the abundence that is here? Speculations are good for debating all of what we do not fully know or understand.
The capture hypothesis of the Moon’s origin cannot explain the essentially identical oxygen isotope ratios of the two worlds.
Yes, I have read similar writings. It is the possibilities that are so key. No one knows for sure. Hypothesis, possibilities, imagining, and alike are all the same. Just different angles and spellings.
It also cannot prove that the Moon formed out of the Earth.
I’ve looked into this a bit last night and so far we seem to’ve only positively identified 2 planets and 1 moon their isotope readings.
There’s research going on to identify the other rocky planets and even that can turn out to be meaningless since then we’ve just gotten 4 samples.
It might just very well mean the average distance to the sun 🙂
We may not yet prove – which is why we need to go back and investigate! – that the Moon originated from the debris that resulted from the hypothetical collision between the proto-Earth and a body the size of Mars, but it is the most plausible; supporting evidence includes: the Earth’s spin and Moon’s orbit having similar orientations, Moon samples indicating the surface of the Moon was once molten, the Moon’s relatively small iron core, lower density compared to the Earth, evidence of similar collisions in other star systems (that result in debris disks), and that giant collisions are consistent with the leading theories of the formation of the solar system. Finally, the stable isotope ratios of lunar and terrestrial rock are identical, implying a common origin .
Yes we have to keep exploring and researching!:)
personally im leaning towards the earth and moon have the same origin.
but as i said based on the isotopes and research so far, we cant fully proof it, nor can we exclude other theories yet. We only positively identified the isotopes of 3 planetary bodies, while there’s 8 planets, 168 moons and possibly hundreds of dwarf planets.
BINGO! You are so spot on,..again! FINALLY, I got into this specific article/post to reply back at you duncan. Took over 3/4 hours to do so. You already know what I said anyways. God Bless you and your “open-mind” and common sense! 😉
Another fine reason to go back to the Moon! Live and learn, eh?
Exactly!
Here’s the (not behind a damn paywall!) paper (PDF):
Crantor, a short-lived horseshoe companion to Uranus.
Thanks!
Thank you!
Not unlike ‘Moore’s Law’ as relates to computer evolution, we are exponentially learning more about the processes of planetary evolution as our knowledge and instrumentation improve. In fact those two evolutions are intricately tied The processes of planetary formation are probably as varied as the ideas used to explain them? I always get a grin when someone claims to know all the facts!
I kept getting “error-404” etc.. . I just could not get into this specific post/article for 3 to 4 hours. Freaky uh. Oh well, such is the life of the internet.
I keep getting that same error message on a couple of the new articles posted today. Frustrating!!!
Yes it is. Been getting them all day.