Universe Guide

What is the Oort Cloud, Hypothesized Area of Comets?

Oort Cloud Facts

What and Where is the Oort Cloud?

The Oort Cloud in brief is an hypothesized area in space that is estimated to be located roughly one light year away from the Sun. Its not like a cloud you would find on the Earth, it doesn't rain. The Oort Cloud is a huge area of space that encompasses our solar system where long term comets are originate before they are sent on their way towards the inner solar system, our planet Earth and the Sun.

To put some more context into the description, the next nearest star Proxima Centauri is four times further away than the Oort Cloud. There has been no definitive evidence that the Oort Cloud exists. There is a debate currently raging as to whether Sedna, the so-called "Tenth planet" is actually part of an inner Oort Cloud. This is because the Sedna is three times further away from the Sun than Pluto, well beyond where the kuiper belt is said to inhabit. Sedna is not the only object that is believed to be part of the Inner Oort Cloud, 2012 VP113 was discovered to be in the same region of space as Sedna. Ref: Carnegie Science

Oort Cloud objects are too far away for our telescopes on Earth to see any of these objects, plus you also need to take into account the fact that they are very small. Thousands upon millions of comets are believed to be "holding up" in the Oort Cloud, waiting to be sent on a journey to the Sun. They are not clustered in one area of the galaxy but surround the entire Solar System like a cloud. No one has ever seen the Oort Cloud so no-one knows how big and how far is ranges out from its location. Comets are actually quite small so you're not going to be able to see one a light year away.

The Oort Cloud will be big, it completely surrounds the Solar System at its perceived distance. How deep the Oort Cloud is an unknown amount. It is unlikely to be a mass of comets equivalent to asteroids in Star Wars V - The Empire Strikes Back.

Planet hiding in the Inner Oort Cloud

There is believed to be two Oort Clouds, an Inner and an Outer. The Outer Oort Cloud would be at the distance theorized by Jan Hendrik Oort whereas the Inner one would be after where the Kuiper Belt has ended.

There is a theory that is being tested that there could be a planet orbiting the Sun at a distance that would match the distance that the Inner Oort Cloud is. The planet is about 10 times the mass of the Earth and would orbit the Sun every 20,000 years.

At such a distance, its going to be hard to spot because its won't have light reflecting off it and our telescopes aren't possible powerful enough to spot. The planet might be at the farthest point so its going to be especially hard to see at this moment in time. We may see it if it interacts with something else, maybe block something out.

The planet is only a theory at the moment. Neptune was first theorized and its position was calculated before it was actually discovered so there's no reason why the same can't hold true for this new planet.

The evidence for the new planet is based on the orbits of other far out objects such as Sedna. All the far off objects are all orbiting in the same direction as the diagram demonstrates, the reason for that is believed to be a massive object in the other direction. Ref: Space.

There could be no planet out there but then they'd have to come up with a reason why all the far off objects that they've seen are all in one direction. There are some objects going in the "void" area but they are far and few compared to the other direction.

If you're interested in being the first to find it, Mike Brown believes the planet is currently in the area of sky populated by the constellations of Taurus and Orion. Daily Star

Artists impression of what the theorized planet nine's assumed path would be.

Space Probe Travelling to Oort Cloud

Voyager 1 is the furthest from Earth that any space probe has ever reached. At the time of writing, Voyager 1 is 20,606,155,702 KM from Earth or 137 times the distance from Earth to the Sun. N.A.S.A. have produced a page that will show you in real time how far each voyager space probe has travelled.

The Oort Cloud is estimated at being between 5,000 and 100,000 A.U. distance. 1 A.U. is the distance between the Earth and the Sun. Voyager 1 was launched in September 1977. Using non-scientific numbers to get an estimation. Lets say the Oort Cloud is indeed at 50,000 AU and if Voyager 1 was to carry on to there, it would take about give or take 14,599 years to get there. By the time the probe got, that is if it reached there and wasn't smashed up en route, humanity might have worked out how to travel faster than light. I know Einstein said travelling faster than light is not possible but if we only accept what we know there's no point in progressing. The on board batteries of Voyager will have run out by the time it has reach the Oort Cloud.

Evidence of the Existence of the Oort Cloud

We have no real evidence that the Oort Cloud exists, we only speculate because of comets. There are no images or pictures of the Oort Cloud because it is so far away that it is only hypothesized about. All pictures of the Oort Cloud are artists impressions including mine. The objects in the Oort Cloud are so small, no camera of ours so far is able to pick them up. The only pictures are artists impressions and illustrations. We have no satellite or space probes out that way and none with a high enough camera resolution to pick them up. Such an object would take thousands of years to get to as we don't have faster than light yet, that is if that is possible.

Jan Hendrik Oort, the man behind the theory

The Oort Cloud is named after Jan Hendrik Oort ( Apr 28, 1900 - Nov 5, 1992 ) who predicted them where they are widely believed to be nowadays. Before Oort, Ernst Opik, who in 1932, an Estonian Astronomer had placed the cloud just outside the solar system. The Oort Cloud is sometimes known as the Opik-Ort Cloud in recognition of the earlier hypothesis. Oort bases his cloud theory on :-

Apart from being associated with the Oort Cloud, Jan also calculated that the centre of the milky way is 30,000 light years away in the direction of the Sagittarius constellation. The below pictures shows the furthest any thing from Earth has ever travelled (Voyager 1), the location of Sedna, the area where the Oort Cloud is and the nearest star. The sizes aren't too scale but its main purpose is to give an indication of where things are. It should be emphasised that the Oort Cloud is a line, it encompasses the entire solar system like a bubble with the Earth and Sun in middle.

Image showing the relative distances from earth of Voyager 1

Creation of the Oort Cloud

The Oort Cloud is believed to have been created five billion years ago when a nebula exploded, creating the Sun and its planets. The intense gravitational strength of Jupiter is said to have pushed them to the outer regions of space. Ref: Harvard

Nemesis, the Brown Dwarf

There is a theory in addition to the Oort Cloud that there is a brown dwarf star called nemesis that interferes with the Oort Cloud, sending comets this way. The idea for Nemesis is based on the perceived cycle of mass extinctions in the geological record, which seem to occur more often at intervals of 26 million years. ref:Daily Mail.

Such an object such as a brown dwarf star would have given off enough radiation that it would have been detected by Earth based instruments which none have been recorded. Nemesis might still exist but might be something else apart from a brown star. With Nemesis being a brown dwarf means it is hard to spot so we can't see it. If it was a yellow dwarf then maybe we'd see light from it and know its here. The closest so far discovered brown dwarf is called WISE 0855-0714 and was discovered in the constellation of Hydra. and is about 7.53 light years away, further out than the Oort Cloud itself. Ref:Space

Do other stars have Oort Clouds?

Our star is not unique, its not special, its small compared to other stars such as Rigel. There's no reason why if the Oort Cloud does exist round our Sun, there shouldn't be any reason why the Oort Cloud shouldn't exist round any other star. Its only speculative as we still have no confirmed proof/evidence that such a cloud actually exists surrounding our own solar system. We may never know unless we gain technology to travel at the speed of light. If we had the ability to travel at the speed of light, it would take a round trip of two years to discover and report back that it existed. It would take a year to get there and a year to get back.

What is the difference between the Asteroid Belt, Kuiper Belt and Oort Cloud?

The main difference between the three is location, the Asteroid Belt is located between the orbits of Mars and Jupiter. They are believed to have been parts of a planets that failed to form because of the immense gravity of Jupiter. The asteroids are small rocky planetoids. In recent years, Ceres, a near spherical planetoid was elevated to dwarf planet status by the International Astronomical Union, the worlds governing body for all things space.

At the edge of the solar system, beyond the planet Neptune is the Kuiper Belt which contains a large number of asteroids. The dwarf planet Pluto is in this region of space. It used to be known as a planet but it was downgraded when other objects such as Eris was found in that region of space and was deemed to be larger than Pluto.

The Asteroid Belt and Kuiper Belt have been verified to exists whereas the Oort Cloud is just a theory. The Asteroid Belt and the Kuiper Belt both consist of asteroids and dwarf planets whereas the Oort Cloud is said to consist of comets, the dirty snowballs. Its not to say that the Oort Cloud doesn't contain asteroids, its just that the theory is that consists mainly of comets.

Related Pages of Interest :-

Comments and Questions

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David K. Bybee
The possibility is fascinating... "There are more things in heaven and earth than are dreamt of in your philosophy..." William Shakespeare
Carl Fucci Jr
John from Holland, I'm not sure how the breakup of one comet suggests that our solar system is young. Do we even have an educated guess as to the age of Schwassmann-Wachmann 3? The comet was "discovered" in 1930, and survived sixty-five years before breaking up, passing every 5.4 years. Even if it were created at the moment of its discovery, it lasted through 12 orbits. Logically speaking, a comet of similar mass and situation would survive in such a manner. So how about Comet Haley which passes every 86 years? Other comets are proven to pass once in thousands or even millions of years, and we need to study further to decide their life-span and insinuate our solar system's age.
George Seovic
Is there any evidence that the oort cloud exists?
If we are to leave the solar system, one day, and travel to the stars, how will we get thru the Oort cloud? Assuming we are traveling at 50% the speed of light, how would we slow-down/turn to dodge all the comets, etc in the Oort Cloud? Or would we just go underneath (around) it? I hope someone can answer this.
Ivan L.
Is there proof? We have seen fuzzy pictures, but for people who doubt the oort cloud to believe it we have to have clear pictures. Not a computer drawn diagram of where it exists or where we think it exist.
John from Holland
The Oort cloud is a myth. Or rather: an imgaginary object, to allow the Bing Bang model meet physical reality. Comets orbit the sun, and break up quite radiply (on cosmological scales) due to melting of the icy rocks inside. Actually, comets (which are part of the solar system since they orbit the sun) are proof that the solar system cannot be billions of years old. http://edition.cnn.com/2006/TECH/space/04/28/comet.breakup/
It has not been conclusively proven as to whether the Oort Cloud exists. This is because of where it is supposed to be situated and that the objects are too small to be currently seen. Sedna was at one time believed to be part of the Oort Cloud but as its too close to the Earth, it is no longer seen as being part of the Oort Cloud. Some people believe Sedna is evidence of an inner (unofficial) Oort cloud. Therefore, the simple answer to the question is no.
Andrew Galloway
"how would we slow-down/turn to dodge all the comets, etc in the Oort Cloud? Or would we just go underneath (around) it? I hope someone can answer this. " Its pretty simple. The likelihood of us running into any type of brick-sized or greater object is extremely low. Keep in mind that these objects are spread out among very vast distances. On the other hand your question does raise a good point. Once we get to, probably 10%, maybe 25% the speed of light, and definently 50% the speed of light, any type of atomic/molecular collision would be catastrophic. I heard that hitting a spec of dust would be like hitting a brick wall in a car. What is more dangerous than the ort cloud is interstellar space, which is riddled with gas and other molecules. Our only real solution would be some type of absorbtion system, basically like the deflector shield on Star Trek, using traditional means of travel. If we were simply warping space time and moving the space around us it wouldn't be as much of an issue. The original project orion back in 1959, which was axed by NASA and the Air Force because nuclear was too political, (they chose project Apollo), absorb the force of nuclear fission explosions. There might be multiple options. Perhaps shaping the spacecraft like a pencil, and having the edges of the craft some type of liquidic or super-heated armor. Another system would use nanobots, if a molecule pierced the hull it would simply travel right through, the carbon nano-tubes would either be designed to chemically heal, would be biological and would regenerate, or would be composed of nano-bots that automatically closed the hole. Perhaps another means of transportation would involve using a laser projected directly out in front of the ship to deflect particles, though this would require vast amounts of energy and probably wouldn't work.
i really liked it but i need info on how many years it takes to travel from the earth to the oort cloud please email me bye. :)
paritosh sharmaMonday, 19th October 2015 11:54:12
The cloud ? made of many gases ,we know but I have one question that from where gases take birth....???
C.D. Campbell
"The Oort Cloud in brief is an hypothesized area in space" "There has been no definate evidence that the cloud exists" So what you are saying is that this crap is made up. What's it doing in a science book, should be in a fairy tale.
Frank Bollinger
Where is the material for the Oort cloud proposed to come from, according to Oort theories and his supporters? I had a similar hypothesis not based on orbit trajetories but the fact that sun has much material coming off of it and I need to do the calculations but the velocities must have an orbit unless they are hyperbolic and leave Suns gravitational influences. Because the materials expelled have different velocities and therefore the orbital spin would distribute orbits of the materials at a band in space that I thought maight be the Oort Cloud. The other part of my hypothesis was that the accumulation of solar expelled materials would eventually accumulate into cometary bodies. Further once these comitary bodies become dense enough will leave into closer orbits in an oscilatory manner and could be cause of the bombardent statistics to go up causing mass extinctions apro. every 70 million years aprox..
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