Blue Heron – A New Wallpaper

 Inspiration for my pictures comes from so many different places.  Blue Heron came one day in March wen I was attending an art exhibit of a very dear friend and AMAZING artist, Tatiana Rhinevault.  Tatiana had done this beautiful painting of a blue heron wading in a small backwater on the Hudson River.  Tatiana’s Blue Heron just pulled me in and I had to see if I could duplicate this wonderful image using Vue and GIMP.  After many, many hours, with countless tweaks, adjustments and renders I finally realized that I would not be able to replicate Tatiana’s artistic interpretation of this beautiful nature scene.  My end result is below.  If you follow the link above you can see Tatiana’s painting to compare.  I highly recommend you take a look at her website and enjoy the amazing skill and depth Tatiana has.  Unfortunately, the pictures of her paintings do not do justice to the originals.  They need to be seen in person.  Take a few minutes and check out her site.

Blue Heron - ThumbEnjoy!

Till next time,

RC Davison

An Amazing Model of Our Universe!


Astronomers, astrophysicists and cosmologists have a very difficult and frustrating life. They can’t touch the star, exoplanet, galaxy, nebula or other celestial object they are studying, nor can they send a probe as a surrogate to take a sample or direct measurement (aside from the few lucky planetary scientists who’ve had missions within our solar system). The topics of their interests lie at distances most people can’t even comprehend. They are restricted to study their subjects with light—infrared, visible, ultraviolet, x-rays, gamma rays and radio waves—that the objects emit or reflect light from another source.

Galactic cluster

Early formation of a galactic cluster along webs of dark matter – Credit: “Illustris Collaboration” / “Illustris Simulation”.

So how do they study these distant objects? They take pictures in light that ranges across the spectrum, and they gather the spectra of these objects. The spectra consist of the light emitted and/or reflected from the objects, broken down it into its constituent parts which indicates what elements are absorbing or emitting the light energy.

Absorption line spectra

Absorption line spectra

They then apply statistical analysis to the reams of data they’ve collected to try to understand and unlock the secrets of the cosmos. These scientists also create clever experiments and conduct observational surveys of the cosmos to provide them with data they can use to further develop their theories. And, they create models. They build computer models to test their theories and see if their models replicate or even come close to matching what they can see in the heavens above. These models are used to predict everything from stellar evolution, planetary atmospheres and black holes to galactic structures and clusters to name a few. There are those that aspire to reach even further. They want to model the evolution of the Universe from the dawn of the big bang to the present day.

A team lead by Mark Vogelsberger (MIT/Harvard-Smithsonian Center for Astrophysics) have done just that. They have developed a sophisticated model of a piece of the Universe (a cube about 326 million light-years (ly) on a side) that incorporates dark matter, as well as normal visible matter. The model, called Illustris, shows the evolution of the Universe from about 12 million years after the big bang to present day, and it maps out the cosmic webs of dark matter, along which normal visible matter collects. The amazing thing about this model is that they can zoom into it and display structures as small as galaxies like our Milky Way galaxy, which look like they could have been photographed by the Hubble telescope! These simulated galaxies exhibit similar chemistries to the galaxies we study today.

Galaxies created in Illustris

Collection of galaxies created in Illustris – Credit: “Illustris Collaboration” / “Illustris Simulation”

The team worked for over five years to develop this model, which incorporates over 12 billion 3D pixels to describe the sample of the Universe. If one were to try to run this simulation on a desktop computer, it would take over 2000 years to finish the calculations. Fortunately, the supercomputers used generated the simulation in 3 months of computer time. The end result contained over 41,000 galaxies embedded in the cosmic web of dark matter and visible matter.

Below is an amazing comparison of the Hubble eXtreme Deep Field image on the left and on the right side, an equivalent image produced by Illustris.

Hubble image vs Illustris image

Hubble Extreme Deep Field on the left and Illustris’ simulation on the right! Credit: “Illustris Collaboration” / “Illustris Simulation”

Take a look at the fascinating videos of this project: Nature – “A Virtual Universe” (narrated and about 4 minutes long) and a longer, unnarrated video “To Compute the Laws of Nature”. Also, check out the Illustris, website for more detailed information and additional images and videos.

Till next time,

RC Davison


(Note: If you visit the “arXiv” links for any of the references you should be able to view an earlier version of the published papers.)

One Step at a Time — New Wallpaper Available

Wallpaper - Pyramids of Egypt

One Step at a Time

Technology has been with us since early man formed the first stone tools.  We tend to forget that as we journey through our days with our cell phones, tablets, GPS and Internet–the state-of-the-art.  But, state-of-the-art is transitory, and tomorrow’s technology will make today’s look ancient.

Five thousand years ago, the ancient Egyptians were perfecting their state-of-the-art in the construction of buildings we marvel at today.  The precision and scope of what they did on the Giza Plateau with the Great Pyramid of Khufu amaze us today with all of our modern science and technology.  But, the Egyptians developed their technology by first building mounds for burial chambers, followed by single level structures — mestabas, which evolved into multi-level structures known as step pyramids, the Pyramid of Djoser is a great example, and the pinnacle of their achievements, the classic pyramids we see at Giza.

The image below celebrates that evolution, the intellect and the ingenuity of this ancient civilization.

Till next time,

RC Davison


A Game of Cosmic Hide and Seek


Playing hide and seek with my children when they were really little was always fun, especially in the beginning when they didn’t realize that I could see them when they covered themselves with a blanket or pillow. In a way, it’s similar with this image of the supernova remnant, DEM L241 located in the Large Magellanic Cloud, a small dwarf galaxy that orbits the Milky Way galaxy. The nebula is the result of a supernova which occurred in a binary star system. The star that is highlighted in the images below is the large companion star that survived the explosion of its partner, which now exists as a black hole or neutron star and is hidden from our view—almost.

Composite image of DEM L241

Composite image of the supernova remnant DEM L241 Image Credit: X-ray: NASA/CXC/SAO/F.Seward et al; Optical: NOAO/CTIO/MCELS, DSS

The above image shows a cloud of dust and gas with a dramatic swath of purple cutting across it. This is a composite image showing the view in the optical (visual) part of the spectrum and the same region in X-rays taken by the Chandra X-ray telescope. (See images below.) The large star of the pair is visible in the optical image and when we look at only the X-rays emitted from the region there is a bright dot in the same spot as the star – the black hole or neutron star hiding from us in the visible part of the spectrum. When these images are superimposed the black hole and the star align.

Optical Image of DEB L241

Optical image of DEM L241 Image credit: Optical: NOAO/CTIO/MCELS, DSS

X-ray image of DEM L241

X-ray image of the supernova remnant DEM L241 Image credit:NASA/CXC/SAO/F.Seward et al

What is remarkable is that this companion star survived the explosion of its partner. The super-dense companion gives itself away in X-rays because it is pulling in surrounding material, possibly from the nearby star, which gets heated to tens of millions of degrees by friction and radiates light in X-rays as a result. The progenitor star for the X-ray source was probably a super giant with a mass at least 25 times the mass of our Sun. The surviving super giant star and the black hole / neutron star orbit each other with a period on the order of tens of days, so they are fairly close together. More in-depth observations of the pair will help determine if the hidden companion is a black hole or a neutron star.

The surviving companion, being a super giant star, will eventually follow the same path as its partner and explode in a supernova, leaving behind a black hole or neutron star.  This newly transformed celestial body will dance a pas de deux with its old partner for billions of years as the light from the supernova eventually fades to black.

For more information check out the Chandra X-ray telescope’s website.

Till next time,

RC Davison

Exile – A Lost Soul

With the current estimate that one out of every five stars in our Milky Way galaxy has an Earth-like planet in the habitable zone, we may be looking at a minimum of about 500 million planets in the galaxy that might harbor life of some sort.  This number is probably easily an order of magnitude higher or more if we consider planets on the fringe of the habitable zones and their moons.

Exile is about one poor sole in one such system that has been banished to a cold, wintery world where he can see his home planet rise every night — not the large lifeless moon, but the distant pale blue dot, flanked by its two moons.

Exile - Wallpaper from orbitalmaneuvers

Till next time,

RC Davison

715 Newly Verified Planets by the Planet Finder, Kepler

On February 26, 2014 NASA announced that the Kepler Space Telescope had found 715 new planets. This is 715 verified planets, not planet candidates, as has been released in the past. This brings the total of verified planets to almost 1700, while the number of planetary candidates is over 3800. These planets orbit around 305 stars and are all multi-planet solar systems.

This is significant because the techniques established to verify these planets bypassed the process where other ground/space based observatories would observe the stars associated with planetary candidates to independently verify the presence of orbiting planets. This was done by measuring the transits of the planets or the star’s “wobble” as the planets tug on the star during their orbit. (For more information on these techniques, see the blogs Finding Exoplanets Part 1: The Transit Method and Part 2 – It’s All About the Mass).

So what did the wizards behind the Kepler telescope come up with to speed up the process? Well, they present an amusing and unique analogy that works quite well when you understand the entire picture. Quoting from their press release*:

“This method can be likened to the behavior we know of lions and lionesses. In our imaginary savannah, the lions are the Kepler stars and the lionesses are the planet candidates. The lionesses would sometimes be observed grouped together whereas lions tend to roam on their own. If you see two lions it could be a lion and a lioness or it could be two lions. But if more than two large felines are gathered, then it is very likely to be a lion and his pride. Thus, through multiplicity the lioness can be reliably identified in much the same way multiple planet candidates can be found around the same star.”

So, if you observe a star and you see evidence of transits—multiple transits—you are very sure that you have a multi-planet solar system; its not random noise. This is because the other sources of error: electrical noise in the detectors, eclipsing binary stars (of which 2165 have been discovered at the time of this article), background eclipsing binary stars or optical ghosting tend to lead to single transit-like events, which would cause confusion in identifying a single planet orbiting the star. This ability to filter out the random noise that might obscure the data leads to a confidence rate of better than 99% for these 715 planets. This conclusion was arrived at after careful statistical analysis of 340 planetary systems, taking into consideration false alarms, false positives and noise in the data. (Check out the references below for links to the papers presented on this technique.)

Within this collection of planets we have four that orbit in the habitable zone of their parent star (meaning liquid water could exist on their surfaces) and are less than 2.5 times the size of Earth. An important thing to keep in mind is that these results come from only the first two years of Kepler data. There is over another year’s worth of data yet to be released on Kepler’s discoveries.

Unfortunately, Kepler ended its planet hunting mission last year due to failures of two reaction wheel controllers (out of 4 total, one being a backup) that are used to precisely point the telescope. Kepler served its main mission and was given an extension to keep planet hunting, but that ended in the spring of 2013 with the failure of the second reaction wheel. It’s interesting to note that having only two reaction wheels prevented Kepler from counteracting the force being placed on it by the Sun’s light pressure, causing it to be unable to lock onto the star it was observing. But, Kepler is not down and out yet as there is a proposal—K2—which will allow the spacecraft to continue its planet hunting to a degree as well as observe star clusters, active galaxies and supernovae.

More planets, more possibilities of life elsewhere in the Universe—as we know it or not! Can’t wait for the James Webb Space Telescope to get into space and come online. The better we can see, the more we can see!

I’ll leave you with a new wallpaper—Change of Season. It’s not too hard to imagine an extraterrestrial planet in some distant star system, with the right geological evolution and astronomical orientation, that its inhabitants have built their own version of Stonehenge to mark the change of seasons.

3D Wallpaper: Change of Season

Change of Season

Till next time,

RC Davison


*Kepler Press Release: For more information, images and video about this topic

Science papers – Lissauer et al, 2014; Rowe et al, 2014

Orcas’ Moon – New Wallpaper Available

Are we the only creatures on this amazing planet that can appreciate the beauty of a full Moon floating above the horizon?  This thought was the seed for this wallpaper of a pod of orcas pausing to take in the view. 

Sophisticated animals, with complex societies and language, killer whales may just be able to appreciate the world around them.  Maybe someday we will be able share their thoughts on a rising Moon.

Check it out!

Orcas' watch a rising full moon

Orcas’ Moon

RC Davison

Wallpapers: Images From Other Places and Times

I’ve added a new page to the ORBITAL MANEUVERS website – Wallpapers: Images From Other Places and Times.

Click to go to wallpaper page.

Tree of Life – Based on the movie, “The Fountain” – Click to go to wallpaper page.

I’ve posted some images that I’ve been working on over the last few years and will add more as they mature. Clicking on the thumbs will bring up the full size image, which you are welcome to download if so inclined. Note that the images are large, typically 1920 x 1080.

As usual, comments are always welcome. Enjoy!

Till next time,

RC Davison


The Multidimensional Constellation of Orion

When we look at the night sky ablaze with stars it is very easy to interpret what we see as a two dimensional image. It’s difficult to associate depth to what we see, because all we see are points of light of varying brightness. We do equate distance with brightness, but overall it’s hard to get a real sense of depth in the night sky, partly because distance can be camouflaged by an object’s brightness.

The Moon and planets give us a little bit more of a visual clue, being bigger and brighter, but that may be more because we know they are closer and not because we perceive a distinct difference in distance. It’s easy to see why the ancient astronomers constructed crystalline shells to transport the stars, planets, Sun and Moon around the sky. The stars were the easiest, as they slowly shifted with the seasons and never changed position, but the planets, Moon and Sun (not to mention comets!) were a different story, and their observed behavior led to very complex solutions to explain their motions.

The constellation of Orion (Wikimedia Commons)

The constellation of Orion, the great hunter, floats across our night sky as the seasons change, just as it did for the ancients. It is a good example of a two dimensional construct that exists in a very three dimensional form—the stars and nebula that we see in Orion are not all at the same distance from Earth. If we could take a ride on a starship and gain a new perspective on this mighty constellation we would see a very different arrangement of stars. Check out the illustration below.

The depth of the Orion constellation. (Click for a larger image.)

This new perspective allows us to see that the star in Orion closest to Earth is Bellatrix, a blue-white supergiant, at 243 light years (ly).  The next closest star is Betelgeuse, the amazingly large red supergiant star at 643 ly. In the not too distant future we will have a ringside seat to a supernova explosion, as Betelgeuse will end its life in one of the most spectacular events in the cosmos.

The next closest star to Earth is Saiph, a blue supergiant that anchors the right leg of Orion. Saiph is followed “closely” by the brightest star in the constellation, Rigel, a blue supergiant about 17 times bigger than our Sun and part of a binary system. Although Saiph and Rigel are both blue supergiants, and Saiph is closer to us, it is dimmer than Rigel. The reason for this is that Saiph is hotter than Rigel and it radiates more light in the ultraviolet end of the spectrum, which we can’t see and therefore appears dimmer in visual part of the spectrum we are sensitive to.

The stars that make up the belt of Orion, Alnitak, Alnilam and Mintaka are all very similar second-magnitude stars, again blue-white supergiants. Alnitak has two smaller companions, making it a triple star system. Alnilam, the most distant of all the stars in the constellation at 1344 ly, makes up for that distance by being the brightest star in the belt. Mintaka is the right-most star in the belt and it is a binary star system with a small companion star.

The stars that make up the constellation of Orion, aside from Betelgeuse, are all hot, young supergiant stars that will end their lives in a supernova. Betelgeuse is just an example of what’s to come, having already entered its red giant stage. They all formed from the same molecular cloud, tens to hundreds of millions of years ago.

There is one more element to Orion that we can easily see with the naked eye, and that is the Orion Nebula, just below Orion’s belt. This nebula is a nest for new stars to form and there are many images on the web that show this in great detail. The nebula is not “within” the constellation as we might imagine it to be but is further from us, with published distances varying from 1300 – 1600 ly. The video below gives a very nice 3D fly through the Orion Nebula.

The Universe is boundless, and we, unfortunately, are at the mercy of our limited senses when we gaze into it. Thankfully we’ve been able to develop the technology that is just beginning to allow us to see the wonders it holds.  Keep looking up and remember, there’s more there than meets the eye…

Till next time,

RC Davison


Water, Water Everywhere?

Water was once a commodity only thought to exist on our blue planet (once we got past thinking that Mars had a canal system and Venus was a tropical paradise!), but as we have advanced our technology and our observation techniques we’ve found evidence of water on our Moon and Mars and now on exoplanets a 1000 light-years away.  The more we look, the more we see that elements and conditions for life as we know it in the Universe are more common than we thought.

NASA has released a study that has detected water in the atmospheres of five exoplanets: WASP-17b, HD209458b, WASP-12b, WASP-19b and XO-1b. These planets are very large and orbit very closely to their stars, earning the moniker, “hot Jupiters”. So they may not be havens for life as we see on Earth.  But, it does point to water being present in those solar systems, and there may be other planets around those stars yet to be discovered in the habitable zone that also have water and moderate temperatures more conducive for life.  Not to mention moons about those planets that also may be habitable.

The Hubble Space Telescope was used to observe the starlight as it passed through the atmospheres of these planets and astronomers teased-out the water signatures from the resulting spectra. The video below describes this discovery and the techniques used in finding the water. It moves along pretty quickly, presenting a lot of information, so you might want to pause it or play it again to pick up on the details.

(NASA’s Goddard Space Flight Center.  Additional animations courtesy ESA/Hubble)

What amazes me is that we are able to glean this information about these planets’ atmospheres at the distances of 500 to 1000 light-years. This is only one more example of the ingenuity and inventiveness the astronomical community has applied to pushing the boundaries of our knowledge.

There was a time when the consensus was that we would not be able to detect planets around another star, but in 1992 two planets were discovered around the pulsar PSR 1829-10. This was a surprise in that astronomers didn’t think a pulsar would have planets orbiting them. The first planet found around a Sun-like star was discovered three years later and is labeled as 51 Pegasi b, which is about 50 light-years away.

Many didn’t believe we would be able to directly image a planet around a star, but that was all changed in 2008 when a team of astronomers using the Gemini telescope in Mauna Kea photographed a planet about 8 times the mass of Jupiter around the star 1RXS J160929.1-210524, which is about 500 light-years from Earth.

Exoplanet circled in red around parent star. Image courtesy of Gemini Observatory

There were a number of other planetary images released later in 2008 by Gemini and Hubble.

As one might imagine, detecting elements and compounds in an exoplanet’s atmosphere was also thought to be beyond our reach, but that too has been disproven with this latest discovery. How long before we find oxygen, indicative of biological processes or the compounds of smog, indicating a potential industrialized society, around some other exoplanet?

These are good examples of what the human species can achieve when facing a challenge. We should have more faith in our abilities and realize that there is very little we can not do if we set out minds to it.  Who knows what else is out there to amaze us!

Till next time,

RC Davison