Discovering JKCS 041

his is a composite image of JKCS041. The blue cloud is an X-ray image from the Chandra Space Observatory. The white galaxies were photographed by the VLT (Very Large Telescope) in Chile. X-ray light pervades the cluster and also projects out in a jet. The jet surrounds a large galaxy. A string of five equally spaced galaxies spirals around the central elliptical.

his is a composite image of JKCS041. The blue cloud is an X-ray image from the Chandra Space Observatory. The white galaxies were photographed by the VLT (Very Large Telescope) in Chile. X-ray light pervades the cluster and also projects out in a jet. The jet surrounds a large galaxy. A string of five equally spaced galaxies spirals around the central elliptical.

The structures and star populations of massive galaxies appear to change as they age, but much about how these galaxies formed and evolved remains mysterious.

Many of the oldest and most massive galaxies reside in clusters, enormous structures where numerous galaxies are found concentrated together. Galaxy clusters in the early universe are thought to be key to understanding the life cycles of old galaxies, but to date astronomers have located only a handful of these rare, distant structures.

Galaxies are normally found in groups or larger collections called clusters. The Local Group consists of our own galaxy, the larger spiral galaxy Andromeda (M31) and several smaller satellites, including the Large and Small Magellenic Clouds.

New research from a team led by Carnegie’s Andrew Newman has confirmed the presence of an unusually distant galaxy cluster, JKCS 041.

“Our observations make this galaxy cluster one of the best-studied structures from the early universe,” Newman said.

Although the team began studying JKCS 041 in 2006, it has taken years of observing with many of the world’s most powerful telescopes to finally confirm its distance. The team used the Hubble Space Telescope to capture sharp images of the distant cluster and split the starlight from the galaxies into its constituent colors, a technique known as spectroscopy. They found 19 galaxies at precisely the same great distance of 9.9 billion light-years, the telltale sign of an early galaxy cluster.

Hubble as seen from Discovery during its second servicing mission

Hubble as seen from Discovery during its second servicing mission

A previous study using the Chandra X-ray Observatory discovered X-ray emissions in the location of JKCS 041.

“These X-rays likely originate from hot gas in JKCS 041, which has been heated to a temperature of about 80 million degrees by the gravity of the massive cluster,” said team member Stefano Andreon of the Osservatorio Astronomico di Brera, who led a companion paper published by Astronomy & Astrophysics.

Artists concept of NASA's Chandra X-ray Observatory. Credit: CXC/NGST

Artists concept of NASA’s Chandra X-ray Observatory. Credit: CXC/NGST

Today the largest and oldest galaxies are found in clusters, but there is a mystery about when and why these giant galaxies stopped forming new stars and became dormant, or inactive. Peering back to a time when the galaxies in JKCS 041 were only 1 billion years old — or 10 percent of their present age — the team found that most had already entered their dormant phase.

“Because JKCS 041 is the most-distant known cluster of its size, it gives us a unique opportunity to study these old galaxies in detail and better understand their origins,” Newman said.

Once massive galaxies enter their dormant phase, they continue to expand in overall size. This is thought to occur as galaxies collide with one another and evolve into a new, larger galaxy. Early clusters are suspected to be prime locations for these collisions, but to the team’s surprise they found that the galaxies in JKCS 041 were growing at nearly the same rate as non-cluster galaxies.

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Disney’s Tech Magic

As a result of heading to Disney World for a much needed break and to “celebrate” the big Five 0, I wanted to make this week’s science article somehow Disney related.

As one would expect Disney World relies heavily on an army of cleanliness minded custodians to keep their sprawling worlds of wonder clean and the visitors away form unsightly messes.

After all those trips to Disney between 1985 & 2013 I finally witnessed one of these myself during our December 2013 visit.

After all those trips to Disney between 1985 & 2013 I finally witnessed one of these myself during our December 2013 visit.

However this is Disney World so even this routine and often boring job often renders a smile-inducing show for the guests.

I have been to Disney World countless times starting all the way back in September of 1985 when we spent our honeymoon there, not realizing where that trip would lead us. I note this because it was not until one of my visits last year that I managed to see this myself.

Often you apparently get 2 characters for the price of 1.

Often you apparently get 2 characters for the price of 1.

At Disney world, janitors called Showkeepers who keep the streets pristine. Many of them have the uncanny ability to draw larger than life versions of beloved Disney characters like Donald Duck, Mickey Mouse, Snow White and even my personal favorite, Mary Poppins.

Using just a mop, some water and a love of all things Disney, the showmen and women pause their janitorial duties now and then to whip up cartoon visions of cinematic legends and new favorites like Stitch, Carl from Up and Mike from Monsters Inc.

Another unrelated Disney World “tech items” is the amazing manner in which they can almost always predict when your “magical express” will be there to get you. When you wait for your ride to one of the parks at your resort you can often know in advance when you will be on you way.

I took this pictures about a year ago when this new technology was just being tested.

I took this pictures about a year ago when this new technology was just being tested.

Ok that’s enough tech talk for this week. Let head off to Disney World.

Have a magical day! 

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Cassini’s View of Uranus

Cassini passes Saturn in this concept art.

Cassini passes Saturn in this concept art.

if there is one constant with NASA’s unmanned spacecraft missions is that we get our money’s worth. These missions often go on for decades and regularly return awe inspiring information as well as amazing photographs of our universe.

Here is a recent example of what I am trying to describe.

NASA’s Cassini spacecraft has captured its first-ever image of the pale blue ice-giant planet Uranus in the distance beyond Saturn’s rings.

The robotic spacecraft briefly turned its gaze away from the ringed beauty of Saturn on April 11, 2014, to observe the distant planet, which is the seventh planet from the sun.

The planets Uranus and Neptune are often referred to as “ice giants” in order to distinguish them from their larger siblings, Jupiter and Saturn, the classic “gas giants.” The moniker derives from the fact that a comparatively large part of the planets’ composition consists of water, ammonia and methane, which are typically frozen as ices in the cold depths of the outer solar system. Jupiter and Saturn are made almost entirely of hydrogen and helium, with smaller percentages of these ices.

This view from NASA's Cassini spacecraft features a blue planet, but unlike the view from July 19, 2013 (PIA17172) that featured our home planet, this blue orb is Uranus, imaged by Cassini for the first time. Credit: NASA/JPL-Caltech/Space Science Institute

This view from NASA’s Cassini spacecraft features a blue planet, but unlike the view from July 19, 2013 (PIA17172) that featured our home planet, this blue orb is Uranus, imaged by Cassini for the first time.
Credit: NASA/JPL-Caltech/Space Science Institute


When this view was obtained, Uranus was nearly on the opposite side of the sun as seen from Saturn, at a distance of approximately 28.6 astronomical units from Cassini and Saturn. An astronomical unit is the average distance from Earth to the sun, equal to 93 million miles (150 million kilometers). At their closest — once during each Saturn orbit of nearly 30 years — the two planets approach to within about 10 astronomical units of each other.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington.

What is Cassini?

On October 15, 1997, a two-story-tall robotic spacecraft launched from the Cape Canaveral Air Force Station and began a journey of many years to reach and explore the outer realm of Saturn, the most distant planet that can easily be seen by the unaided human eye. In addition to Saturn’s interesting atmosphere and interior, its vast system contains the most spectacular of the four planetary ring systems, numerous icy satellites with a variety of unique surface features, a huge magnetosphere teeming with charged particles that interact with the rings and moons, and the intriguing moon Titan, which is slightly larger than the planet Mercury, and whose hazy atmosphere is denser than that of Earth.

Cassini Configuration

Cassini Configuration

Looking Back on Planet Earth


On July 19, 2013, the probe was pointed towards Earth (above) to capture an image of the Earth and the Moon. The event was unique as it was the first time NASA informed the people of Earth that a long-distance photo was being taken in advance. The imaging team said they wanted people to smile and wave to the skies, with Cassini scientist, Carolyn Porco, describing the moment as a chance to “celebrate life on the Pale Blue Dot”.

More information about Cassini is available at the following sites:

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Europa’s RFI

File:Water vapour plumes on Jupiter's moon Europa (artist's impression).jpg

Water vapor plumes on Jupiter’s moon Europa.

Here is something different. NASA is looking for help exploring Europa. And like any good business looking for information NASA has issued an RFI. I have not seen this happen before so I thought it was kind of cool that NASA was seeking help in this way.

Europa is one of the most intriguing world’s in our solar system. The surface is composed of water ice and it’s surface is one the smoothest in the solar system.

The RFI is being made available to science and engineering communities for ideas for a mission to Europa that could address fundamental questions of the enigmatic moon and the search for life beyond Earth.


This artist’s concept shows a simulated view from the surface of Jupiter’s moon Europa. Europa’s potentially rough, icy surface, tinged with reddish areas that scientists hope to learn more about, can be seen in the foreground. The giant planet Jupiter looms over the horizon. Credit: NASA/JPL-Caltech

The RFI’s focus is for concepts for a mission to Europa that costs less than $1 billion, excluding the launch vehicle that can meet as many of the science priorities as possible recommended by the National Research Council’s 2011 Planetary Science Decadal Survey for the study of Europa.

“This is an opportunity to hear from those creative teams that have ideas on how we can achieve the most science at minimum cost,” said John Grunsfeld, associate administrator for the NASA Science Mission Directorate at the agency’s headquarters in Washington. “Europa is one of the most interesting sites in our solar system in the search for life beyond Earth. The drive to explore Europa has stimulated not only scientific interest but also the ingenuity of engineers and scientists with innovative concepts.”

NASA has studied a variety of mission designs and concepts in previous years and currently is funding the development of technologies that will be needed for the science instruments for a Europa mission. Congress appropriated $80 million for this work in Fiscal Year 2014, and the Fiscal Year 2015 budget proposal requests an additional $15 million.

Previous scientific findings point to the existence of a liquid water ocean located under the moon’s icy crust. This ocean covers Europa entirely and contains more liquid water than all of Earth’s oceans combined.

The Decadal Survey deemed a mission to the Jupiter moon as among the highest priority scientific pursuits for NASA. It lists five key science objectives in priority order that are necessary to improve our understanding of this potentially habitable moon.

The mission will need to:

Characterize the extent of the ocean and its relation to the deeper interior

• Characterize the ice shell and any subsurface water, including their heterogeneity, and the nature of surface-ice-ocean exchange

• Determine global surface, compositions and chemistry, especially as related to habitability

• Understand the formation of surface features, including sites of recent or current activity, identify and characterize candidate sites for future detailed exploration

• Understand Europa’s space environment and interaction with the magnetosphere.

Although Europa and Jupiter’s other moons have been visited by other spacecraft, they were each limited to a single distant flyby of these satellites. NASA’s Galileo spacecraft, launched in 1989 by the space shuttle, was the only mission to make repeated visits to Europa, passing close by the moon fewer than a dozen times.

In December 2013, NASA’s Hubble Space Telescope observed water vapor above the moon’s frigid south polar region. This provided the first strong evidence of water plumes erupting off the moon’s surface, although researchers are still working to verify the existence of these plumes.

Any mission to Europa must take into account the harsh radiation environment that would require unique protection of the spacecraft and instruments. In addition, spacecraft must meet planetary protection requirements intended to protect Europa’s potentially habitable ocean. These requirements are very strict and involve ensuring that a viable Earth organism is not introduced into the Europa ocean.

I would love to respond to the RFI, I just don’t think I am qualified.

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Investigating Kepler-186f

The fictional USS Enterprise orbiting a "Class M" planet in a habitatal  zone.

The fictional USS Enterprise orbiting a “Class M” planet is a habitable zone.

The question of whether life exists on other planets will always remain a curiosity as we continue venturing into space. The continued popularity of my favorite TV show for example, “Star Trek” is just one example of our fascination with the possibility of life on other worlds.

We could be stepping closer to answering this question as NASA has recently found the first Earth-Size planet in the ‘habitable zone’ of another star.

According to NASA, the Kepler Space Telescope found an Earth-sized planet orbiting a star in the habitable zone. This is important because it is in this zone where the range of distance from a star to a planet [in orbit] where liquid water is capable of collecting on the surface which of course leads to the possibility of life.

A sketch of Kepler-186f [SOURCE: NASA]

A sketch of Kepler-186f [SOURCE: NASA]

The new planet has been dubbed Kepler-186f, and it is about 500 light-years from Earth in the constellation Cygnus. It orbits a star, which is classified as an M dwarf, or red dwarf — half the size and mass of our sun.

Kepler-186f orbits its star once every 130-days and receives one-third the energy from its star that Earth gets from the sun. This puts it near the outer edge of the habitable zone.

The brightness of its star at high noon is only as bright as Earth’s sun appears about an hour before sunset. Further, NASA isn’t quite sure yet, but it believes Kepler-186f’s surface is rocky.

Kepler-186f is not alone over there. It has four companion planets, called Kepler-186b, Kepler-186c, Kepler-186d, and Kepler-186e. These other planets make their way around their sun every four, seven, 13, and 22 days respectively and they are too hot for any life, that we know of to exist on them.

Kepler-186f is 10% bigger and occupies its star's 'habitable zone' where temperatures would allow liquid surface water

Kepler-186f is 10% bigger and occupies its star’s ‘habitable zone’ where temperatures would allow liquid surface water

Size is another important key here. While planets have been discovered in the habitable zone before, they have not been the same size as Earth. The four companion planets, for example, all measure less than 1.5 times the size of Earth. Also, previously discovered planets in the habitable zone were were at least 40 percent larger in size than Earth.

With Kepler-186f being about the same size as Earth, we can have a clearer idea of behaviors, topography, etc. But as of right now, its mass and composition are unknown.

Unfortunately, whether it contains life is also unknown at this time. But Just like Captain Kirk and his crew it is always worth investigating when discovering new planets in these “habitable” zones.

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Earth Stuck in the Middle

This Monday night’s lunar eclipse reportedly proved just as amazing as expected to those able to view it. Here on the east coast we unfortunately had cloudy skies so we missed out this time. But here is some information anyway so you can get ready for our next one later this fall.



A “Blood Moon”

Nicknamed a “blood moon,” this lunar eclipse’s color was similar to the majority of lunar eclipses. This has to do with Earth’s atmosphere’s propensity for longer-wavelength light (e.g., the reds, oranges and yellows seen in sunrises and sunsets).

What is a Lunar Eclipse?

A lunar eclipse occurs when the Moon passes directly behind the Earth into its shadow. This only occurs when the Sun, Earth and the Moon are aligned very closely , with the Earth in the middle.

However, according to NOAO Astronomer Stephen Pompea, the lunar eclipse’s hue means more than just a pretty moon.

“The study of the color of lunar eclipses can be used to understand dust in the stratosphere including the amount and particle size of dust injected by volcanic eruptions,” he said. “Understanding the amount of dust can help scientists create better models of climate change.”

More Chances For Viewing

Although we here in the north east missed out of this particular lunar eclipse, there are a couple more chances this year. Three more lunar eclipses will be occurring on:

  • Oct. 8, 2014
  • April 4, 2015
  • Sept. 27, 2015

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Visiting a Dwarf Planet

Two weeks ago I wrote about the discovery of 2012 VP113, beyond the Kuiper Belt. The discovery of this world is exciting to many because it demonstrates just how crowded the outer reaches of our solar system is. At one time it was believed Pluto was the 9th planet and orbited the very edge of our solar system. However this is known no longer to be true, Pluto is not really planet and there are many objects even larger then Pluto on the deepest edges of our solar system.

There are many who still miss Pluto “officially” being a planet, and in fact there remains a large number of you who still count it as one.

Our Solar System is an amazing place, and the discovery of other large objects beyond Neptune doesn’t negate what Pluto actually is.

Image credit: NASA’s The Space Place, via

There are some very special properties that the inner, rocky worlds of our Solar System share with the Gas Giants, and none of the other candidates have them. As we are now learning the details about thousands of solar systems in our galaxy, we need to better understand just what makes something a planet and why that’s important.

Over the last few decades, powerful new ground and space-based observatories have completely changed previous understanding of the outer Solar System. Instead of being the only planet in its region, like the rest of the Solar System, Pluto and its moons are now known to be just a large example of a collection of objects called the Kuiper Belt.

Astronomers in 2006 voted and demoted Pluto down to the newly created classification of “dwarf planet”.

Winter on Dwarf Planet Pluto as seen from Pluto's surface - Space Art Illustration; Kuiper

Winter on Dwarf Planet Pluto as seen from Pluto’s surface – Space Art Illustration; Kuiper

Here are the primary reasons Pluto lost it’s ranking as a planet:

  • It needs to be in orbit around the Sun – Yes, so maybe Pluto is a planet.
  • It needs to have enough gravity to pull itself into a spherical shape – Yes – Pluto is a sphere. So far so good.
  • It needs to have “cleared the neighborhood” of its orbit – Uh oh. Here’s the rule breaker. According to this, Pluto is not a planet. 

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Bright Lights on Mars

H. G. Wells (1866–1946)

H. G. Wells (1866–1946)

Is there life on Mars?  This is a question that has haunted mankind since we could first see the red planet in the night sky. HG Wells so captured this dream in his classic 1898 “The War of the Worlds”, which has been filmed countless times.

The news story I am about to tell really does not indicate the possibility of life on Mars but it’s fun to wonder…

NASA’s Curiosity Rover recently grabbed a photo that has many dreamers wondering again, “Is there life on Mars?”.

This is being asked again by some because of images taken by NASA’s Curiosity Mars rover on April 2 and April 3 which include bright spots, which might be due to the sun glinting off a rock or cosmic rays striking the camera’s detector.

What could that bright light be on Mars?

What could that bright light be on Mars?

The rover took the image just after arriving at a waypoint called “the Kimberley.” The bright spot appears on a horizon, in the same west-northwest direction from the rover as the afternoon sun.

“In the thousands of images we’ve received from Curiosity, we see ones with bright spots nearly every week,” said Justin Maki of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., leader of the team that built and operates the Navigation Camera. “These can be caused by cosmic-ray hits or sunlight glinting from rock surfaces, as the most likely explanations.”

If the bright spots in the April 2 and April 3 images are from a glinting rock, the directions of the spots from the rover suggest the rock could be on a ridge about 175 yards from the rover’s April 3 location.

The bright spots appear in images from the right-eye camera of the stereo Navcam, but not in images taken within one second of those by the left-eye camera. Maki said, “Normally we can quickly identify the likely source of a bright spot in an image based on whether or not it occurs in both images of a stereo pair.

“In this case, it’s not as straightforward because of a blocked view from the second camera on the first day.”

At the Kimberley and, later, at outcrops on the slope of Mount Sharp inside Gale Crater, researchers plan to use Curiosity’s science instruments to learn more about habitable past conditions and environmental changes.

What was that “bright spot”? Everyone is asking. What do you think?

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One of Our Planets is Shrinking


Our sun’s closest neighbor, Mercury.

Our most inner planet Mercury has always been a small world. However the planet became slightly smaller as its interior cooled, which caused Mercury to shrink, buckling its surface and creating numerous cliffs and ridges. Now, after studying 5934 of these features, researchers have recently reported in Nature Geoscience that Mercury’s contraction was much greater than previously thought.

During the past 4 billion years, the planet’s diameter decreased by 7 to 14 kilometers. Earlier estimates date back to data from Mariner 10, a spacecraft that flew past Mercury three times during the 1970s but saw less than half the planet.

Then in 2011, the MESSENGER spacecraft began orbiting the sun’s innermost planet, imaging the entire surface. The greater estimate of shrinkage accords with models that predict how much a rocky planet should contract as its interior cools; the new work may also lend insight into the evolution of extrasolar planets that, like Mercury. Unlike Earth, Mercury lacks any moving continents. It is one big continent spanning the entire planet.

Now that you know that Mercury is actually shrinking here is some cool information about the planet closest to our sun.

A Year in Mercury is Just 88 Days Long
One day on Mercury lasts the equivalent of 176 Earth days. Mercury is nearly tidally locked to the Sun and over time this has slowed the rotation of the planet to almost match its orbit around the Sun

Mercury is the Second Densest Planet
Even though the planet is small, Mercury is very dense. Each cubic centimetre has a density of 5.4 grams, with only the Earth having a higher density. This is largely due to Mercury being composed mainly of heavy metals and rock.

Mercury has Wrinkles

Wrinkle ridges and depressed troughs combine in this depressed crater in the Goethe basin on Mercury.

Wrinkle ridges and depressed troughs combine in this depressed crater in the Goethe basin on Mercury.

As the iron core of the planet cooled and contracted, the surface of the planet became wrinkled. Scientist have named these wrinkles, Lobate Scarps. These Scarps can be up to a mile high and hundreds of miles long.

Mercury has a Molten Core 
In recent years scientists from NASA have come to believe the solid iron core of Mercury could in fact be molten. Normally the core of smaller planets cools rapidly, but after extensive research, the results were not in line with those expected from a solid core. Scientists now believe the core to contain a lighter element such as sulphur which would lower the melting temperature of the core material. It is estimated Mercury’s core makes up 42% of its volume, while the Earth’s core makes up 17%.

Mercury is Only the Second Hottest Planet
Despite being further from the Sun Venus experiences higher temperatures. The surface of Mercury which faces the Sun sees temperatures of up to 427°C, whilst on the alternate side this can be as low as -173°C. This is due to the planet having no atmosphere to help regulate the temperature.

Mercury is the Most Cratered Planet in the Solar System

mercuryspider-580x401 Unlike many other planets which “self-heal” through natural geological processes, the surface of Mercury is covered in craters. These are caused by numerous encounters with asteroids and comets.

Only Two Spacecraft Have Ever Visited Mercury

Artist's impression of the Mariner 10 mission

Artist’s impression of the Mariner 10 mission

Owing to its proximity to the Sun, Mercury is a difficult planet to visit. During 1974 and 1975 Mariner 10 flew by Mercury three times, during this time they mapped just under half of the planet’s surface. On August 3rd 2004, the Messenger probe was launched from Cape Canaveral Air Force Station, this was the first spacecraft to visit since the mid 1970′s.

Mercury is Named for the Roman Messenger to the Gods
The exact date of Mercury’s discovery is unknown as it pre-dates its first historical mention, one of the first mentions being by the Sumerians around in 3,000 BC.

Mercury Has an Atmosphere (sort of)
Mercury has just 38 percent the gravity of Earth this is too little to hold on to what atmosphere it has which is blown away by solar winds. However while gases escape into space they are constantly being replenished at the same time by the same solar winds, radioactive decay and dust caused by micrometeorites.

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Exploring The Edge of Our Solar System

Artist's conception of the cold distant Sedna. The sun is a tiny point of light 8 billion miles away from the red planetoid. A hypothesized tiny moon appears nearby.

Artist’s conception of the cold distant Sedna. The sun is a tiny point of light 8 billion miles away from the red planetoid. A hypothesized tiny moon appears nearby.

Our known Solar System can be divided into three parts: the rocky planets like Earth, which are close to the Sun; the gas giant planets, which are further out; and the frozen objects of the Kuiper belt, which lie just beyond Neptune’s orbit. Beyond this, there appears to be an edge to the Solar System where only one object, Sedna, was previously known to exist for its entire orbit. But the newly found 2012 VP113 has an orbit that stays even beyond Sedna, making it the furthest known in the Solar System.

Sedna was discovered beyond the Kuiper Belt edge in 2003, and it was not known if Sedna was unique, as Pluto once was thought to be before the Kuiper Belt was discovered. With the discovery of 2012 VP113 it is now clear Sedna is not unique and is likely the second known member of the hypothesized inner Oort cloud, the likely origin of some comets.

Some of these inner Oort cloud objects could rival the size of Mars or even Earth. This is because many of the inner Oort cloud objects are so distant that even very large ones would be too faint to detect with current technology.

The Oort Cloud is a hypothesized spherical cloud of predominantly icy planetesimals that may lie roughly 50,000 AU, or nearly a light-year, from the Sun.

The Oort Cloud is a hypothesized spherical cloud of predominantly icy planetesimals that may lie roughly 50,000 AU, or nearly a light-year, from the Sun.

Exploring the Oort Cloud

There are three competing theories for how the inner Oort cloud might have formed. As more objects continue to be found, it will be easier to narrow down which of these theories is most likely accurate. Here are the three theories.

A rogue planet could have been tossed out of the giant planet region and could have perturbed objects out of the Kuiper Belt to the inner Oort cloud on its way out. This planet could have been ejected or still be in the distant solar system today.

A close stellar encounter could have put objects into the inner Oort cloud region.

Inner Oort cloud objects are actually captured extra-solar planets from other stars that were near our Sun in its birth cluster.

The outer Oort cloud is distinguished from the inner Oort cloud because in the outer Oort cloud, starting around 1500 AU, the gravity from other nearby stars disturbs the orbits of the objects, causing objects in the outer Oort cloud to have orbits that change drastically over time. Many of the comets we see were objects that were perturbed out of the outer Oort cloud. Inner Oort cloud objects are not highly affected by the gravity of other stars and thus have more stable and more primordial orbits.


Beyond the Oort Cloud

As you can see we are still learning about our solar system and no one is 100% sure of where it really ends and interstellar space begins. What is known however is that the Oort cloud is the boundary between confines of our solar system and deep space. Interstellar space, beyond the Oort cloud is where our sun no longer has any gravitational influence.

Artist concept of Voyager 1 and Voyager 2 leaving our solar system.

Artist concept of Voyager 1 and Voyager 2 leaving our solar system.


There is solid evidence Voyager 1 has left the heliosphere and entered interstellar space.

Scientists say the spacecraft became the first man-made object to enter interstellar space on August 25, 2013. It is believed that Voyager 1 is now beginning is exploration of the deeper Milky Way. Not bad for a spacecraft launched back in 1977!

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