Ice Volcanoes on Ceres

Speaking of an extended Dawn mission orbiting Ceres, scientists are not wondering why Ceres does not have more craters.  Could it be ice volcanoes?  Data from the Dawn mission may offer clues.

Simone Marchi, a senior research scientist at the Southwest Research Institute in Boulder, Colorado, stated:

We concluded that a significant population of large craters on Ceres has been obliterated beyond recognition over geological time scales, which is likely the result of Ceres' peculiar composition and internal evolution...Whatever the process or processes were, this obliteration of large craters must have occurred over several hundred millions of years.

Maybe it does make sense for Dawn to stick around a learn a little more about this fascinating dwarf planet buried in the asteroid belt.

This video from NASA's Jet Propulsion Laboratory shares even more details. 

Extended NASA Missions

Earlier this month NASA extended nine space missions via the 2016 Senior Review of Operating Missions, which area provided below in alphabetical order:

-Dawn;

-Lunar Reconnaissance Orbiter (LRO);

-Mars Atmospere and Volatile Evolution (MAVEN); 

-Mars Odyssey orbiter;

-Mars Reconnaissance Orbiter (MRO);

-New Horizons;

-the Opportunity and Curiosity Mars rovers; and

-support for the European Space Agency’s Mars Express mission.

That is quite an investment in Mars, but let's not forget ongoing missions as well such as Cassini around Saturn and Juno orbiting Jupiter. 

Unfortunely, Dawn is done exploring the asteroir belt. While a visit to another asteroid (145 Adeona) was proposed, the panel decided to keep the spacecraft in orbit around Ceres to learn more about the dwarf planet. 

Luckily, New Horizons will continue to explore the outer reaches of the solar system. The panel approved a mission to Kuiper Belt Object MU69 by 2019. So the exploration continues. 

Great Image: The Solar System's Smaller Worlds

The image above recently posted by The Planetary Society is labeled "Every round object in the solar system under 10,000 kilometers in diameter, to scale." This impressive collection represents 2 planets, 18 or 19 moons, 1 or 2 asteroids, and 87 "trans-Neptunian" objects. 

You can see how the moons Ganymede and Titan outside Mercury, and our own Moon exceeds the size of Pluto.

The image below shows the objects we have already visited, including the recently explored Ceres and Pluto. We are making great progress in our explorations of the solar system. 

Image Credit: Montage by Emily Lakdawalla. Data from NASA / JPL, JHUAPL/SwRI, SSI, and UCLA / MPS / DLR / IDA, processed by Gordan Ugarkovic, Ted Stryk, Bjorn Jonsson, Roman Tkachenko, and Emily Lakdawalla.

Studying Methane on Mars

One of the tasks of the ExoMars mission on its way to Mars is to study the methane in the Red Planet's atmosphere. Specifically, we want to know more about its source since we know life can create the gas. Of course, geology and other factors could also be at work.

A recent Discovery article highlighted one more culprit- comets. In a research paper, NASA's Marc Fries stated: 

Individual instances of  methane detection on Mars have been reported on five occasions via Earth-based telescopic observations, once by the ESA Mars Express mission over a two-month period, and eight times by the Mars Science Laboratory (MSL) rover. For all instances, Mars experienced a close interaction with  the  orbit  of   a  periodic  comet  within  16  days  previous  to  the  observation  of   methane.  Moreover, all methane  observations  correlate  with  interactions  between  Mars  and  seven  comets.  These  comets  have  all been previously identified as the likely sources of  meteor showers on Mars.

An interesting idea. And more scientific speculation about our solar system, similar to guesses about the source of the mysterious bright spots on Ceres (see below), that demonstrates how much we do not yet know about our own neighborhood.

Ceres, Part II; Colonization

Space.com had an interesting article recently on Ceres, asking if we would be able to colonize the planet as is done in the SyFy television series The Expanse.  Its an interesting question, just as The Expanse has been a fascinating take on humans expanding into the solar system, including occupying Mars and the asteroid belt.

Here is how the dwarf planet is described in the future on the Syfy website:

The largest object in the asteroid belt between Mars and Jupiter, the dwarf planet Ceres has become the port city of the Belt. A subterranean city has been bored into the rocky interior of the planetoid, which is home to some 6 million people. Thanks to the spin created by Tycho engineers, the residents of Ceres experience artificial gravity in the form of centrifugal force, which presses away from the core of the planetoid, and out towards the exterior of the station. An endless stream of trade flows through its docks, but the majority of the wealth flows back to Earth and Mars. The closer you travel to Ceres' Core, the more impoverished the living conditions.

It would be nice to have one person on Ceres, never mind 6 million.  The Space.com article discussed the difficulties of living on the surface with only 1/40th the Earth's gravity, noting:

The moon has lava tubes, and some people have talked about repurposing these structures into habitats. An alternate idea for Ceres — a place bereft of the silicate lavas needed to create such tubes — would be to use inflatable habitats (similar to those in development by Bigelow Aerospace) and then bulldoze rocky material over the habitat to serve as a radiation shield.

Living off the land on Ceres may be more difficult than doing so at the moon, but it's hard to say yet as the dwarf planet is just this year getting its first close-up. Still, any water ice on Ceres seems (so far) to be buried in the dwarf planet's interior, despite the discovery of a definitive signature of water ice in Ceres' atmosphere. The water ice on Earth's moon may be a little closer to the surface, at least at the poles.

It is interesting that we are now discussing "any water" on Ceres when back in 2005 Space.com was noting that scientists believed Ceres had more fresh water than the Earth.  The Dawn spacecraft page at NASA still notes the large quantities of water on Ceres, even though the Dawn mission results have been somewhat tentative.  The European Space Agency's Herschel space observatory detected water vapor on and around the dwarf planet, so the water is there, but the quantity still seems to be a guess. 

It is very intriguing to speculate on future mission to Ceres and the asteroid belt.  The existence of water, as well as other resources, is the key reason the colonists in The Expanse are in the belt - to supply the needs of humans living on Mars and elsewhere. Let's just hope the future colonists are a little happier than those in the SyFy series.

Ceres, Part I: New NASA Photos

NASA's Dawn spacecraft has captured some amazing close-up images of the dwarf planet Ceres.  The image above is the younger Kupalo Crater, which is about 16 miles across, shown from an height of 240 miles.  And the image below is the floor of the Dantu Crater.  You can see a brighter spot on the right hand side that appears to be similar to those scientists have been pondering in the Occator Carter, shown in the very bottom image.  It is believed they may represent brine that came to the surface.

Top 15 Space and Astronomy Stories from Slate

Phil Plait in Slate put together a helpful video discussing the Top Space and Astronomy Stories in 2015, including New Horizons arriving at Pluto, the Dawn spacecraft over Ceres, and reusable rockets.  He also has time to mention the science in the movie The Martian as well as a cameo by Elon Musk on the Simpsons.  It is quite a list, as it has been quite a year. 

You Knew It Was Coming: The Pluto Petition

Now that New Horizons has provided us with a fascinating view of the dwarf planet Pluto, some are thinking it is time to restore Pluto to its rightful place among the full planets.  If you agree, you might want to visit change.org, which has a petition with about 4,300 names on it as of today.  

And what does this group want?  Hopefully, the petitioners can capture the attention of the International Astronomical Union (IAU), which is the same culprit that knocked Pluto off the planetary list:

The IAU meets again for its general assembly in August 2015. And in the coming weeks, New Horizons will collect unprecedented amounts of data about the Pluto system, calling in to question the definition set forth by the IAU.

I am wondering if I need to start a petition for Eris, also floating out there with Pluto, or even Ceres (shown below), now being studied by the Dawn spacecraft.  With the five dwarf planets, we would have 13 officials planet for now.  I say the more the merrier. 

A Mountain on Ceres?

While all of the attention is on Pluto at the moment, let's not forget that the Dawn spacecraft is exploring Ceres, another dwarf planet.  The image above of Ceres' surface was taken in mid June and demonstrates continuing mysteries on the planet's surface beyond those strange bright spots.  But what I find most interesting about the story below is how Dawn will be orbiting this dwarf planet for millions of years.  Now that is impressive.

Here is the story as told by NASA on June 30th:

What created this large mountain on asteroid Ceres? No one is yet sure. As if in anticipation of today being Asteroid Day on Earth, the robotic spacecraft Dawn in orbit around Ceres took the best yet image of an unusually tall mountain on the Asteroid Belt's largest asteroid. Visible at the top of the featured image, the exceptional mountain rises about five kilometers up from an area that otherwise appears pretty level. The image was taken about two weeks ago from about 4,400 kilometers away. Although origin hypotheses for the mountain include volcanism, impacts, and plate tectonics, clear evidence backing any of these is currently lacking. Also visible across Ceres' surface are some enigmatic light areas: bright spots whose origin and composition that also remain an active topic of investigation. Even though Dawn is expected to continue to orbit Ceres, officially dubbed a dwarf planet, for millions of years, the hydrazine fuel used to point Dawn's communications antenna toward Earth is expected to run out sometime next year.

Image Credit: NASA, JPL-Caltech, UCLA, MPS/DLR/IDA

Light Spots on Ceres: Is it a Shopping Center?

NASA's Jet Propulsion Laboratory (JPL) is asking for your guess about the bright spots spotted on Ceres.  JPL asks:

Can you guess what's creating those unusual bright spots on Ceres? On March 6, NASA's Dawn spacecraft began orbiting Ceres, the largest body in the main asteroid belt between Mars and Jupiter. Even before the spacecraft arrived at the dwarf planet, images revealed mysterious bright spots that captivated scientists and observers alike. Until Dawn gets a closer look over the next few months, it's anyone's guess what those spots could be. So, go ahead! Cast your vote...

The possible options are (1) volcano, (2) geyser, (3) rock, (4) ice, (5) salt deposit, and (6) other. You can see a better image below, taken on May 16th by the Dawn spacecraft.  I believe the most likely source of the light is reflection on ice, but you never know.  When I voted (no peaking), about 30 percent voted for ice, but 38 percent voted for "other."  I would like to know what some of those "other" scenarios might be, but we may not know for some time (or ever).  The mystery continues.

Dawn Has Arrived

The Dawn spacecraft is now in orbit around the dwarf planet Ceres. Marc Rayman, Dawn mission director, stated:

Since its discovery in 1801, Ceres was known as a planet, then an asteroid and later a dwarf planet...Now, after a journey of 3.1 billion miles (4.9 billion kilometers) and 7.5 years, Dawn calls Ceres, home.

Now the mission can begin to study this mysterious water-loaded planet (estimated to have more water than all the Earth's oceans), including the bright spots on its surface. It seems as though we know more about exoplanets light years away than this nearby neighbor. That is about to change.

Great Image: Approaching the Dwarf Planet Ceres

The images above taken from NASA's spacecraft Dawn are only the parts of an amazing mission to Ceres, the inner solar system's only dwarf planet.  Having studies the asteroid Vesta earlier in its mission, Dawn will now provide visuals and data on Ceres far beyond any thing we have to date.  

Here is NASA's explanation: 

What are those bright spots on asteroid Ceres? As the robotic spacecraft Dawn approaches the largest asteroid in the asteroid belt, the puzzle only deepens. Sharper new images taken last week and released yesterday indicate, as expected, that most of the surface of dwarf planet Ceres is dark and heavily cratered like our Moon and the planet Mercury. The new images do not clearly indicate, however, the nature of comparatively bright spots -- although more of them are seen to exist. The enigmatic spots were first noticed on Texas-sized Ceres a few weeks ago during Dawn's approach. The intriguing mystery might well be solved quickly as Dawn continues to advance toward Ceres, being on schedule to enter orbit on March 6. 

Image Credit: NASA, JPL-Caltech, UCLA, MPS/DLR/IDA