Yeah, yeah I know; it's a movie about giant mechanized aliens so it's not exactly a realistic movie. However, I do expect movies to be at least peripherally aware of the laws of planetary motion.

For those of you that have not seen the trailer for the continuing saga of the autobots and decepticons -- Transformers: Dark of the Moon -- the premise is that the Apollo moon landings were undertaken for the secret purpose of exploring an alien crash site. Fair enough, sounds like a reasonable sci-fi story element. But there's a problem.

Since the astronauts land in the Sea of Tranquility, they are on the side of the Moon that is facing Earth. So, in the movie they have to wait until they rotate around to the dark side of the Moon. Did none of the screenwriters know that the Moon is tidally locked with the Earth, meaning that the same side of the Moon always faces the Earth?

One could argue that those involved with the script may have been aware of this fact, but assumed that most of their viewers wouldn't know the difference. (Which may be a reasonable argument considering the pervious installment in the series had plot holes large enough to drive a truck through.) Even if this was the case this plot element isn't necessary to making the story work.

Presumably, the reason the writers did this was to explain why the actions of the astronauts were not being recorded. (Which is even more ridiculous since they are apparently still in communication with Houston during this part -- which they wouldn't have been if they really were on the opposite side of the Moon -- making the whole event even more irrelevant and erroneous.) The problem is that nothing the astronauts did on the mission was visible from Earth anyway. They very well could have carried out secret tasks on the surface of the Moon and there is no way for us to know.

The simple reason is that the Moon is simply too far away for us to observe objects that small on the surface. Take the Hubble Space Telescope, one of the worlds most powerful telescopes. It is nearly diffraction limited at an angular resolution of about 0.05 seconds of arc. This means that the telescope can not resolve individual objects smaller than 60 meters (~197 feet) in diameter, and can't distinguish between objects that are less than about 93 meters apart (just shy of the length of a football field).

So it is unnecessary to devise a way in which the astronauts could escape the watchful eye of the rest of the world. We only saw what NASA wanted us to see in the first place. All they would have to do is shut off the feed from the cameras on the surface and we would be blind to what they were doing. The only other way that images of the action could have been captured was if an orbiting lunar probe passed overhead. But presumably said probe would have also seen the downed spacecraft, so it would have been a moot point.

The point being that the incorrect use of the movements of our Moon is unnecessary to the story line. It would be nice if they could at least get some basic astronomy right. Then again, it is a Michael Bay movie so their should still be lots of action and explosions to keep things interesting.

Well, it is that time of year. Everywhere you look on the internet there are top 10 lists. The top 10 songs of 2010, the top 10 news stories, the top 10 sports plays. Frankly, I have become disenchanted with such lists. Therefore, I bring you not a top 10, but rather a simple look back at some of my favorite story lines from the last 12 months.

This retrospective starts and ends really with the boondoggle that was the handling of NASA and her future. There was the cancelation of the over-bloated Constellation Program. Then there was a partial reinstatement of some of its projects.

Ultimately, NASA is looking to further its manned space program through a hodgepodge of rockets (some private, others NASA designed) and capsules. The waters are still muddy, but the short story is that NASA will live on and America is still set to play a major role in space exploration.

And lest we forget the gulf oil spill, the extent of which was seen from space (see image above). But we also celebrated the first 10 years of the International Space Station.

It was also a year in which we began to take a closer look at some of the most important bodies in our Universe, the Sun and the Moon. Not to mention some of the new close-ups we got of passing asteroids - information that will eventually help us better understand the evolution of our solar system.

And we can't forget the announcement that scientists had found a potentially habitable planet. Which was quickly followed by lots of controversy and clarification.

Speaking of controversy, CERN got up and running, colliding charged particles at record energies and the Earth wasn't sucked into a black hole like some had suggested would happen. Maybe we just got lucky.

NASA had created their own list of interesting events from 2010, so if you can head over there for their take. It's a new year and it should be an exciting one at that.

Image Credit: NASA

NASA's Jet Propulsion Laboratory has released some new Mars videos that reveal some pretty spectacular moments in the martian sky.

Using the Mars Exploration Rover Opportunity scientists were able to capture a series of images and combine them together to simulate what it would be like to be standing on the surface of Mars and marveling heavenward.

About 17 minutes worth of images taken on Nov. 4 and Nov. 5, 2010 were used to create a 30 second snapshot of a martian sunset using the onboard panoramic camera (Pancam). The entire sequence is possible through the use of three special filters that allow the camera to observe the Sun while still capturing color information. The result is the Sun draped in a blue halo due to the presence of atmospheric dust particles.

The second movie captured Phobos, one of Mars' moons, transiting in front of the Sun. Using Pancam images spaced 4 seconds apart, the 30 second movie shows the tiny moon moving across the Sun just before sunset on November 9, 2010.

Aside from being visually interesting, such images allow scientists to monitor slight changes in the orbital path of Mars' moons, further revealing details about the interior of the red planet. According to Jim Bell, of Cornell University, "For nearly seven years now, we've been using the cameras on Spirit and Opportunity to help us experience Mars as if we were there, viewing these spectacular vistas for ourselves. Whether it's seeing glorious sunsets and eclipses like these, or the many different and lovely sandy and rocky landscapes that we've driven through over the years, we are all truly exploring Mars through the lenses of our hardy robotic emissaries."

You can check out more information about the movies' release and as well as other videos through JPL.

Image of Phobos Partially Occulting the Sun on November 9, 2010; Credit: NASA/JPL-Caltech/Cornell/Texas A&M

The competition is still underway, but it looks like the final resting places of two of the active space shuttle fleet -- Atlantis, Discovery and Endeavour -- are beginning to come into focus.

It has long been assumed that Space Shuttle Discovery was headed to the Smithsonian's Stephen F. Udvar-Hazy Center in Chantilly, Va. where the prototype orbiter Enterprise currently resides. While this still appears to be the case, there are some hurdles that need to be cleared before anything is finalized.

The primary difficulty is that the cost to prep, fly and deliver the orbiter to the museum is expected to cost nearly $29 million, an amount that NASA has not been prepared to pay. But it seems that Congress is preparing legislation that would compel the government controlled agency to pony up the dough. Ultimately, whatever arrangement is arrived at, it seems destined that Discovery is headed to Virginia.

The race for the remaining two shuttles has been much more competitive. Institutions had been invited to submit proposals outlining their desire to obtain one of the craft, with specific details of how the shuttle would be displayed. You can even check out some of the proposed displays for yourself.

One interesting turn is the rise of the Kennedy Space Center's bid to claim one of the other two vehicles. Previously thought to lag behind several of the other proposals the Kennedy Space Center may now be a front runner.

As reported by collectSpace.com the Visitor Center portion of the Kennedy Space Center, located just down the road from the preparation areas and launch pads, has now released a new master plan to their facility that includes a new $100 million, 64,000 square-foot facility to house a shuttle.

The new display will allow visitors, according to the center, to see a shuttle "in flight, showing how the spacecraft worked in space and providing a unique vantage point for guests looking at this remarkable vehicle up-close." And while the cost to transport one of the shuttles to the visitor center would be considerably cheaper than flying one to a far off destination, there are still costs that would be incurred; estimated at roughly $20.5 million.

Nothing official has been announced yet, but it appears that there are two front runners to house the final resting places of two of the three shuttles.

Image Credit: Kennedy Space Center's Visitor Center

Over the last week I put forth a proposal that would allow Pluto to rejoin the planet fraternity and a few days latter submitted an argument as to why said proposal is flawed. So where do we go from here?

Let's take a fresh look at our solar system through the eyes on an alien. What would we see? How would we classify the objects orbiting the yellow main sequence star in the middle?

Of course there are the obvious isolated objects -- the Terrestrial and Jovian worlds -- that comprise the canonical planetary system as defined by the IAU. But then you would notice two other regions filled with millions, or perhaps billions, or tiny bodies all in orbit around the central star.

The first (moving radially out from the Sun) region is what we call the asteroid belt. Made up of tiny fragments of rock and dust, some measuring the size of a grain of sand, this torus of material between Mars and Jupiter is what remains of a planet that never was.

During the formation of the planets it is hypothesized that Jupiter began a rapid evolution, devouring material all around it. As it pulled mass from the neighboring orbit the gravity began to rise rapidly. Eventually its gravity was so great that it began to disrupt the formation of the planet that was congealing nearby.

As the matter in the inner solar system began to cool, the remnants of the failed planet orbiting just beyond Mars could no longer grow through impacts with other matter. And the asteroid belt was born.

At least one of the planetary remnants, that we know call Ceres, is large enough to have formed a spherical shape under the influence of its own gravity. But it remains stuck in a sea of material left behind from the destructive gravitational force of Jupiter.

But just because Ceres is large enough to have collapsed under its own gravity and orbits the Sun, is that really justification for calling it a planet? In reality it is only a planetary building block.

If we were an alien race studying this solar system, we would conclude that the asteroid belt is merely the remains of a planet that was either destroyed by some cataclysmic event, or simply never formed at all; leftovers from the collapse of the solar nebula. We would never deem to call any of the tiny intermixed rocks a planet.

A similar analysis of the region beyond Neptune, the space we call the Kuiper belt, would draw a similar conclusion. During the rapid formation of the gas giant, the increased gravitational pull drew in material from the body forming in the distance. This disruption further impeded the growth of the world, ultimately leading it its demise.

The remnants of the rocky-icy body were broken apart and scattered. The Kuiper belt exists as the leftovers of a planet that was never given the chance to properly form.

But the question, like that of Ceres, is what to do with the objects that are left behind? With some of them large enough to collapse into spheroids under the pressure of their own gravity, it is tempting to label them as planets, the way that we label the other non-star spheroids in the solar system.

The reality, however, is that these objects are not themselves planets but parts of planets. And it is this fact that I believe the IAU was attempting to address. While I dislike the wording of the rule (I find it too broad and difficult to enforce, particularly when it is applied to extrasolar bodies), the spirit of what they are trying to accomplish makes sense.

I would love for Pluto to remain a planet, but it's challenging to identify a scientific argument that allows the tiny orb to dwell among the planetary ranks while still identifying it as part of a broader system of objects that are themselves all part of a dead planet. That said, I challenge the IAU to conjure up a more robust definition; one that makes clear the standards of what it means to achieve planethood.

Of course these are just my opinions. And I respect those of whom would disagree (unlike some scientists out there), because while I see the merit in distinguishing planets from spheroidal objects that are remnants of planets, I can also see why some would argue that it shouldn't matter how the object came to be or where it is located. (A great resource for those in this camp can be found here.)

And herein lies the problem, no matter what decision is made there are those that are going to argue that there is scientific justification for the other side. So the debate is not likely to end anytime soon.

There is also the question of what to call Pluto and its cohorts. The now ubiquitous dwarf planet is a popular choice. But there are those that find this terminology misleading. I prefer planetary remnant as it more clearly identifies what the object truly is. But at this point it is just semantics. Agree? Disagree? Let me know in the comments section below.

December 21 marks the winter solstice, but in 2010 it will also host a dramatic lunar eclipse.

The total eclipse begins at 2:41 a.m., lasting until until 3:53 a.m. (EST). The best viewing time will at 3:17 a.m. (EST) when the Moon will appear at its reddest. There will appear darker from about 1:00 a.m. until about 5:30 a.m. (EST), though it might be difficult to notice a difference except during totality.

So why does the Moon appear red, and not go completely dark like the Sun does during a solar eclipse? Some of the Sun's light can still reach the surface because of the bending of the light around the Earth. But to complicate the matter further, the Earth's shadow is actually broken up into two distinct parts (see image below).

The umbra is the portion of the Earth's shadow that does not contain any direct radiation from the Sun. While the penumbra is the region of space where the Earth is only partially blocking the light from the Sun. As the Moon moves from outside the shadow toward the umbra the Moon will begin to appear darker and darker.

The focus of the umbra is the point at which all three celestial bodies are properly aligned. Despite this, the eclipse does not completely drape the Moon in darkness because light from the Sun can actually be refracted through the Earth's atmosphere on its way to the Moon.

The result of this refraction is that the Sun's light will be separated into individual colors. The more directly aligned the Earth, Moon and Sun are the Moon's color will transition to more of an orange hue, then red. This is actually the same phenomenon that causes the sky to appear reddish at sunset and sunrise.

When the Moon is fully contained within the umbra, the Moon is said to be in total eclipse. On Tuesday this part of the event will last about 72 minutes, while the Moon will be in at least partial eclipse for about four and a half hours.

Top Image Credit: Fred Espenak, www.MrEclipse.com

I must say, I am quite surprised. Last week I posed a solution to the is Pluto a planet controversy, offering up some insight and criticism about the current state of play. And to my surprise I got very little response.

Occasionally I employ this tactic in the classroom, posing a solution or theory and challenge the class to push back. Considering the veracity with which both sides of this controversy lay siege to the opposition, I expected a lively debate and an onslaught of emails. Yet... nothing.

Perhaps it is because the academic year is winding down and folks have better, more important things to do. In any case, I thought I would stoke the fire a bit.

In my blog I argued that Pluto, like its trans-Neptunian cousins, should be considered a planet; further arguing that the broad definition of a planet should be subdivided into three classes: Terrestrial, Jovian and Dwarf. My reasoning stood on several well reasoned points. Or were they really that reasoned? Let's take a look.

First I cracked down on the IAU's rule that a planet must clear its path of debris, offering evidence that Earth wouldn't clear Pluto's orbit either. The logic behind the IAU's proposal is that Pluto and the other dwarf planets are part of a larger system of objects known as the Kuiper belt. Essentially all of these objects formed at the same time from the same volume of material and all have roughly the same composition. Picking out one, or even several of these objects, from among the millions of objects and setting it (them) apart didn't make sense.

In essence, the IAU argues, these objects are part of a separate region of the solar system; apart from the planetary region. Sure there may be some planet-like objects in the Kuiper belt, but since they all generally lie beyond the reaches of Neptune they shouldn't be lumped in with the spheroids dwelling nearer to the Sun.

Sound ridiculous? Well consider this, what do we do with Ceres? For the uninitiated, Ceres is the remnant of a failed planet, torn apart by the massive gravity of Jupiter. Located in the region of space between Mars and Jupiter in the torus known as the asteroid belt, Ceres is large enough to achieve a spheroidal shape, but is still considerably smaller than Pluto.

Yet even some die hard Pluto-ites have a hard time including Ceres as a planet for one reason or another, not the least of which is that it is easier to simply refer to it as a large asteroid. But would that not dictate that Pluto should simply be referred to as a large Kuiper belt object or even (gasp) a large comet, an object with which it most closely shares its composition? Suddenly the answer is not so clear.

Further complicating the question is the realization that any planet definition should work equally well for objects orbiting stars other than our own. As my colleague Dr. Chad Wallace pointed out, the stumbling block for Pluto's planethood may well extend to some of the 500+ extrasolar "planets" that have already been discovered.

As we begin to hone our ability to detect smaller and smaller worlds, we may encounter Earth-sized and smaller objects orbiting at considerably large distances from their host star. In these cases the planet, like Pluto, may not have cleared its orbital path, but it is unlikely that we would be able to tell. So should we classify the object as a planet or not? Whatever the definition it should extend to other planetary systems and not just ours.

I also pointed out in my previous post that Pluto and Charon should be considered a binary dwarf planetary system because the center of mass of the system (the barycenter) is located outside the surface of Pluto. This makes sense as we observe binary systems all the time. But these are almost exclusively star systems, the definition has never really been extended to planetary objects.

The trouble with such a definition is that it raises questions about what it means to be a binary system. For instance, what do we do with Jupiter? That may seem like a strange thing to ask, but hear me out. As Mike Brown, noted astronomer responsible for the discovery of a Pluto-like object known as Eris, the center of mass of the Jupiter-Sun system actually lies outside the Sun. So should Jupiter not be considered a planet because it doesn't technically orbit a star? Should the Jupiter-Sun system be known as a binary system instead?

Almost no one is arguing for a binary definition of the Jupiter-Sun system. Yet, ignoring the fact only weakens the assertion that, because the barycenter of the Charon-Pluto system lies just outside Pluto's surface, it is a binary system.

So, are you confused yet? Considering changing sides? Well stay tuned, we'll wrap this discussion up later this week and try and bring some clarity to the topic. In the meantime feel free to debate away in the comments section below.

Hubble Images of Pluto's Surface; Credit: NASA/HST

In 2006 the International Astronomical Union, in a move that has resonated around the globe, demoted a small ball of rock and ice out in the outer throws of the outer solar system from planet status; relegating the tiny orb to merely dwarf planet existence.

The outcry, both from within and outside of the scientific community, has reached deafening levels. So much so that even Neil deGrasse Tyson, director of the Hayden Planetarium in New York and one of the first to begin casting Pluto to the side in public exhibition, has received considerable hate mail. From little kids.

Let's look at what the definition of a planet according to the IAU: the object must have sufficient gravity to become round, but not so massive that it ignites nuclear burning like a star (in effect placing a mass limit of about 13 times the mass of Jupiter) and finally that it has cleared its orbital path of debris. This last one is a problem for Pluto. But planetary astronomers have pointed out that it would be for virtually any of the terrestrial planets (including Earth) if it orbited the Sun at Pluto's radius.

What if we just took the first two conditions laid forth by the IAU and let it go at that: massive enough to be round, but not so much that it ignites nuclear burning? That would leave the eight objects that we already consider planets and add in the ones that we currently call dwarf worlds.

I think this is fine, but at the same time believe that we should take it a step further. You see, in some regards I agree with the actions of Dr. Tyson and his colleagues at the Hayden Planetarium. There needs to be further subdivision to group like-planets together. In fact, we already do this.

Anyone taking an astronomy class is likely familiar with the terms Terrestrial Planet (those comprising the first four positions out from our Sun) and Jovian Planet (the subsequent four by distance). So why not just add a third subclass: Dwarf (of whatever term you prefer)?

These objects would be distinguished from the Terrestrial planets in that they are smaller, and far less dense (Terrestrial worlds have a density of about 5.5 grams per cubic centimeter, while Pluto is around 2 grams per cubic centimeter). The structure of these Dwarf Planets likely contain rocky cores (instead of iron dominant) and are characterized by rocky and icy surfaces.

Such a definition would allow Pluto to rejoin the ranks of planethood and create a third distinct subclass of planet. So is that it? Well, almost. There are other dwarf planets to consider, and one of them is very close to Pluto. In fact it is so close that most astronomers call it one of Pluto's moons, but I disagree.

Charon, Pluto's companion, being about half the size of Pluto is massive enough that the barycenter of the system (effectively the center of mass) actually lies outside Pluto's radius. This means that both objects orbit a point between them, rather than one object orbiting the other. For this reason, it is more correct to designate them as a Binary Dwarf Planetary system. While slightly confusing, it is strictly speaking the correct classification.

So there you have it. Pluto is a planet. And so is Charon. And so are a handful of others out in the Kuiper belt. And while all these objects are planets, there are part of a subclass of planets called dwarf planets. At least this is how it works in my mind. How about you? Do you like the IAU's definition? Prefer mine? Have one of your own that you think is better? Sound off in the comments section and let the world know what you think.

Hubble Portrait of the "Double Planet" Pluto & Charon; Image Credit: Dr. R. Albrecht, ESA/ESO Space Telescope European Coordinating Facility, NASA

You think you're smart don't you? Yeah, I can see the smugness from here. Well now is your chance to prove just how brilliant you really are.

Under resourced and staring at a mountain of data, NASA's Jet Propulsion Laboratory (JPL), in conjunction with some european collaborators, is seeking help from colleagues around the world to help solve one of the greatest mysteries of the Universe -- the nature and distribution of this stuff called dark matter. Previous experience in physics and astronomy not required.

Beginning this week, scientists can begin work on GREAT 2010 (GRavitational lEnsing Accuracy Testing). The purpose of the competition is to find ways to analyze images where galaxies have become distorted by interspersed gravitational fields, much of the time coming from dark matter.

This phenomenon, known as weak gravitational lensing or weak lensing for short, is important to understanding the nature and structure of space-time. Since most of the matter in the universe appears to be dark, such studies are one of the few ways we have to get accurate data on the distribution of matter throughout the Universe.

Performing analysis on images containing weak lensing is computationally intensive, so researchers are hoping to spur interest among their computer science brethren. While the techniques developed by the competitors will inform the direction of future NASA missions and research.

To participate in the challenge, visit the GREAT 2010 webpage to register. Then you will be given pictures of fuzzy galaxies that have been partially occulted by dark matter.

In some cases the distorting effect is so slight that it will be invisible to the naked eye. Of course the problem is further complicated as imperfections in the telescopes accumulating the photons will distort the images to a greater degree than the bending from dark matter.

Participants will submit their solutions to the thousands of images being put forth by JPL and the winners will be announced at the closing ceremony of a workshop held at JPL. Those finishing at the top will receive some as-yet-unnamed "cool gadget". But they greater prize, according to JPL, is the "satisfaction of having brought the world one step closer to understanding what makes our universe tick". Umm, sure. Personally I'm going for the cool gadget.

This Hubble image is an example of how gravitational lensing is used to map the distribution of dark matter. Courtesy of NASA, ESA, and Z. Levay (STScI)

Stop me if you've heard this one before. A federally funded space agency, with a multi-billion dollar budget, announces a plan to launch one of its storied space orbiters. Then they delay the launch. Again. Then again. And again. Followed by, yup you guess it, another delay.

Ok, so it doesn't quite work as comic shtick, but it is nonetheless the reality of our current space program. In yet another delay, the swan song for the Space Shuttle Discovery (also known as SAS-133) has been pushed back into 2011.

While I may be making light of the most recent set back, the importance of the decision should not be over looked. The mandate was in the name of safety, as multiple cracks in the Shuttle external fuel tank has NASA administrators concerned.

Understanding the cause of the cracks, in essence to insure that no more could arise before launch, is important in the continually safety minded space program. After a pair of space tragedies, where two craft and their brave crew were lost, NASA engineers and administrators are not willing to send more personnel into space without fully understanding any anomalies.

So, when the members of the latest Program Requirements Control Board were not satisfied that enough tests had been done, they delayed the launch and will wait for further analysis. As such, the launch will not take place before February 3, 2011. And because of this delay, the following mission will also be postponed until at least April 1.

Image Credit: NASA