What is the Oort Cloud?

Very few people know much about one of the most exciting collection of objects in our Solar System; the Oort Cloud. In this post, we’re going to explore and find out What is the Oort Cloud.

Scientists and Astronomers have long studied the Oort Cloud, which has been determined to be an extended shell of icy objects and particles that exist in the outermost regions of the solar system.

The Oort Cloud is named after the well renowned astronomer Jan Oort, who is recognized as the first person to have recognized and pointed out its existence to the scientific community. Since then, the Cloud has become a subject of great study and beyond, and all this has, with time, revealed immense amounts of information for the world to dwell upon.

What is the Oort Cloud:

The Oort Cloud is found to be roughly spherical, whereas its origin is said to date back to those long-period comets that have clustered the Solar System since the early days of its creation. According to the astronomer Jan Oort, this cloud of particles is actually the remains of the disk of material that basically gave birth to the Sun and planets.



Image by TypePad, http://goo.gl/NWlQz6


Today, astronomers refer to such primeval objects in a different way and have termed it a protoplanetary disk. However, most Scientists and Astronomers theorize about the study of the Oort Cloud, that the material that formed the Oort Cloud itself, must have formed closer to the ‘then’ existing Sun in the earlier epochs of our Solar System formation and development.

In later stages, as the planets grew and developed, the gravitational influence of the then ‘so called’ Solar System must have scattered many icy objects out into the outer Solar System (light years from our current Sun’s position): thus forming the Oort Cloud, as we are aware of now.

Where is the Oort Cloud:

In terms of location and position, the Oort Cloud is said to exist near the inner limits of around 2,000 AU from the Sun. The Cloud is indeed vast and extensive, and stretches nearly half way to our Solar Systems nearest star, Proxima Centauri. The shape of the Cloud is genuinely spherical and consists of an outer cloud and interestingly, a doughnut shaped inner cloud as well!



Image by NASA, http://goo.gl/IPMjng


According to studies conducted shortly after the Oort Cloud was discovered, the outer Oort Cloud may contain more several trillions of objects larger than 1 km and billions that measure 20 kilometers in diameter. While the total mass is not known, rough estimates suggest that it may have the combined mass of approximately 3×1025 kilograms; meaning that the Oort Cloud’s mass is equal to or greater than that of five Earths!

What Makes Up the Oort Cloud:

The components of the Oort Cloud are just amazing and so few people even know about it, much less what it is made of. Over the last several years, information and data has been collected by studying comets that escape from the Oort Cloud and come close to Earth.



“Comet Hale-Bopp” by w:User:Mkfairdpm from English Wikipedia – From English Wikipedia (the same filename). Licensed under CC BY-SA 3.0 via Commons – https://goo.gl/adgA9g


These objects are essentially composed of icy volatiles namely; water, ethane, methane, carbon monoxide, hydrogen cyanide, and ammonia.

Cool Facts About the Oort Cloud:

In effort to bring greater awareness to the Oort Cloud, let’s have a look at some of the interesting facts that aren’t as well know about the Oort Cloud.

As Old as it Gets:

The Oort Cloud is no new discovery indeed. In fact, it is said that the Cloud contains nuclei reserves that date back to the actual origin and creation of our Solar System. Some say that the Oort Cloud might have been formed around the time of the Big Bang and could be possibly some of the first objects to be created from the Big Bang!

Engulfing the Rest:

While the objects that make up the current Oort Cloud were likely formed billions of years ago around the time of the Big Bang, its current formation and location are thought to have taken shape around the time our Solar System’s star, the Sun, formed around 4.5 billion years ago.



Image by AstroBites, http://goo.gl/ilsYZ6


As the Sun was forming, its gravitational pull attracted massive quantities of elements from surrounding areas of the Milky Way Galaxy. These elements later formed the planets and moons of our Solar System and would have attracted the distant icy objects that make up the Oort Cloud, today.

Mind Blowing Big: 

While experts and missions are interested in forever finding out the actual number of objects that exist in the Cloud, estimates and studies suggest that it is near impossible to accurately give a number. Thus, the guesses go up to several of trillions different (sized) objects that exist in the Cloud! That’s huge beyond imagination!

New Members Welcomed:

As time goes by, new additions and objects are being welcomed and included in the company of the Oort Cloud. In relation to this, it is important to mention that the planetoid, Sedna, which was discovered as late as 2003, is also now conceived as an extended part of the Oort Cloud.



“Kuiper belt – Oort cloud-en” by NASAThis SVG image was created by Medium69.Cette image SVG a été créée par Medium69.Please credit this : William Crochot – http://goo.gl/kq92HA. Licensed under Public Domain via Commons – https://goo.gl/zQNI4p


Similarly, as more and more studies are done throughout the course of time, it is also now being contested that many of the long-period comets, those which take more 200 years to complete an orbit around the Sun, may also have their origins in the Oort Cloud, as well!

Exploratory Missions:

While theories and predictions are continuously being made regarding the Oort Cloud, a detailed and well researched mission is yet to probe further into the matter, unfortunately.

Over the years a few attempts have been made; such as Voyager 1. Voyager 1 is acclaimed to be the fastest and farthest of the interplanetary space missions to date. As it has only recently passed Jupiter and the outer regions of the Solar System, it won’t reach the Oort cloud for about another 300 years and will take roughly 30,000 years to pass through it.

On the other hand, around 2025, Voyager 1’s radioisotope thermoelectric generators will no longer supply enough power to operate any of its scientific instruments; preventing any meaningful exploration of the Oort Cloud by Voyager 1.



Image by University of Oregon, http://goo.gl/p1EC3o


The other four mission probes presently escaping the Solar System will also be non-functional by the time they reach the Oort Cloud. Unfortunately, to fully understand and study the information and data relating to the Oort Cloud; we’d need to create a special space probe to be sent (very fast) directly to the Oort Cloud and not be damaged or out of its power supply when it reaches those vastly distant regions of our outermost Solar System. For now, we shall resort to studies conducted and data collected here on Earth, coupled with speculations.

The Oort Cloud is indeed a phenomenon of gigantic proportions that more people need to know about and be aware of. It is vast and distant, possibly extending up to an area which might be unreachable and unknown for many years to come.

While possibilities and guesses can only make the Oort Cloud a more subject attractive, there will also inevitably come a time when more studies and data will reveal additional mysterious of the wondrous Oort Cloud!




Featured image by NASA, http://goo.gl/mC4vbx

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