Photo of Venus and the Moon taken on Jan 26, 2012. The new moon is at the top right and Venus is at the bottom left. Credit: Gadi Eidelheit.
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The planet Venus is so bright that when conditions are right, it can be visible in full daylight. This weekend, and especially on Saturday, February 25, 2012, conditions should be just right for seeing Venus in the daytime. Our friend Gadi Eidelheit sent us his tips for seeing Venus, and says it is easier to see Venus when it is far from the Sun and less affected by its glare, so make sure that the Sun is blocked by a building or a tree. If you have a clear blue sky in your location early Saturday afternoon, try first locating the crescent Moon at about 1 pm local time. At this time, the Moon will be in the southeastern sky, about 60 degrees above the horizon.
When you find the Moon, look a short distance directly below it to find Venus. The planet will appear as a tiny white dot in the sky. You can also use sky maps or internet sites (such as Heavens-Above) to find out where Venus is relative to the Moon.
If you don’t see Venus during the day, try to see Venus immediately at sunset; and right now, the Moon, Venus and Jupiter are lining up for triple conjunction at dusk, and with clear skies, it will be a great view that is almost impossible to miss!
But for seeing Venus on subsequent days, try to stand in the same position where you saw it before, but 20 minutes before sunset. Try to locate Venus a little higher up and to the East from where it was a day before. Do so for several days, each time a little earlier.
You can also try to use binoculars to locate Venus. Safety first, make sure that the Sun is completely blocked and that you can not accidentally look directly at it through the binoculars! Although Venus is bright, it will not appear through binoculars if they are not focused properly. In order to use binoculars, focus it beforehand (such as the evening before) on Venus and make sure that the focus does not change. Now the binoculars are focused and you can use them to see Venus in the day. After you find Venus through the binoculars, try to see it without them.
If you get images of Venus in the daytime or of the triple conjunction, you can submit them to our Flickr page.
If your location does not have clear skies for the triple conjunction, The online Slooh Space Camera will webcast views from various observatories around the world, beginning at 0230 GMT (9:30 pm EST, 6:30 pm PST) both nights this weekend (Feb. 26 and 27). Access the webcast here.
Slooh will provide footage from multiple observatories around the world, including Arizona and the Canary Islands off the coast of Africa. The broadcast can be accessed at Slooh’s homepage, found here: http://events.slooh.com/
A rare home video that captured the explosion of the space shuttle Challenger Shuttle on Jan. 28, 1986, has been found. Bob Karman and his family were on a return trip from vacation to Disney World, and filmed the launch from the Orlando airport. This is thought to be only the second amateur video taken of the launch, back when home video cameras were just becoming popular.
Here’s a gorgeous view from the International Space Station, taken by the Expedition 30 crew on Feb. 4, 2012 as the station passed into orbital dawn. The greens and reds of the aurora borealis shimmer above Earth’s limb beyond the Station’s solar panels as city lights shine beneath a layer of clouds.
As the ISS travels around the planet at 17,500 mph (28,163 km/h) it moves in and out of daylight, in effect experiencing dawn 16 times every day.
From that vantage point, 240 miles (386 km) above the Earth, the lights of the aurora — both northern and southern — appear below, rather than above.
See this and more images from the Space Station’s nightly flights here.
Also, here’s a time-lapse video made from photos taken by the Expedition 30 crew a few days earlier. Enjoy!
(Video courtesy of the Image Science & Analysis Laboratory, NASA Johnson Space Center.)
The Faulkes Telescope. Credit: Faulkes Telescope/LCOGT
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Using and getting the most out of robotic astronomy
Whilst nothing in the field of amateur astronomy beats the feeling of being outside looking up at the stars, the inclement weather many of us have to face at various times of year, combined with the task of setting up and then packing away equipment on a nightly basis, can be a drag. Those of us fortunate enough to have observatories don’t face that latter issue, but still face the weather and usually the limits of our own equipment and skies.
Another option to consider is using a robotic telescope. From the comfort of your home you can make incredible observations, take outstanding astrophotos, and even make key contributions to science!
The main elements which make robotic telescopes appealing to many amateur astronomers are based around 3 factors. The first is that usually, the equipment being offered is generally vastly superior to that which the amateur has in their home observatory. Many of the robotic commercial telescope systems, have large format mono CCD cameras, connected to high precision computer controlled mounts, with superb optics on top, typically these setups start in the $20-$30,000 price bracket and can run up in to the millions of dollars.
A look at the Faulkes Telescope South inside. Credit: Faulkes Telescope/LCOGT
Combined with usually well defined and fluid workflow processes which guide even a novice user through the use of the scope and then acquisition of images, automatically handling such things as dark and flat fields, makes it a much easier learning curve for many as well, with many of the scopes specifically geared for early grade school students.
Screenshot of the Faulkes Telescope realtime interface. Credit: Faulkes Telescope/LCOGT
The second factor is geographic location. Many of the robotic sites are located in places where average rainfall is a lot lower than say somewhere like the UK or North Eastern United States for example, with places like New Mexico and Chile in particular offering almost completely clear dry skies year round. Robotic scopes tend to see more sky than most amateur setups, and as they are being controlled over the Internet, you yourself don’t even have to get cold outside in the depths of winter. The beauty of the geographic location aspect is that in some cases, you can do your astronomy during the daytime, as the scopes may be on the other side of the world.
iTelescope systems are located all over the globe. Credit: iTelescope project
The third is ease of use, as it’s nothing more than a reasonably decent laptop, and solid broadband connection that’s required. The only thing you need worry about is your internet connection dropping, not your equipment failing to work. With scopes like the Faulkes or Liverpool Telescopes, ones I use a lot, they can be controlled from something as modest as a netbook or even an Android/iPad/iPhone, easily. The issues with CPU horsepower usually comes down to the image processing after you have taken your pictures.
Software applications like the brilliant Maxim DL by Diffraction Limited which is commonly used for image post processing in amateur and even professional astronomy, handles the FITS file data which robotic scopes will deliver. This is commonly the format images are saved in with professional observatories, and the same applies with many home amateur setups and robotic telescopes. This software requires a reasonably fast PC to work efficiently, as does the other stalwart of the imaging community, Adobe Photoshop. There are some superb and free applications which can be used instead of these two bastions of the imaging fraternity, like the excellent Deep Sky stacker, and IRIS, along with the interestingly named “GIMP” which is variant on the Photoshop theme, but free to use.
Some people may say just handling image data or a telescope over the internet detracts from real astronomy, but it’s how professional astronomers work day in day out, usually just doing data reduction from telescopes located on the other side of the world. Professionals can wait years to get telescope time, and even then rather than actually being a part of the imaging process, will submit imaging runs to observatories, and wait for the data to roll in. (If anyone wants to argue this fact…just say “Try doing eyepiece astronomy with the Hubble”)
The process of using and imaging with a robotic telescope still requires a level of skill and dedication to guarantee a good night of observing, be it for pretty pictures or real science or both.
Location Location Location
The location for a robotic telescope is critical as if you want to image some of the wonders of the Southern Hemisphere, which those of us in the UK or North America will never see from home, then you’ll need to pick a suitably located scope. Time of day is also important for access, unless the scope system allows an offline queue management approach, whereby you schedule it to do your observations for you and just wait for the results. Some telescopes utilise a real time interface, where you literally control the scope live from your computer, typically through a web browser interface. So depending on where in the world it is, you may be in work, or it may be at a very unhealthy hour in the night before you can access your telescope, it’s worth considering this when you decide which robotic system you wish to be a part of.
Telescopes like the twin Faulkes 2-metre scopes, which are based on the Hawaiian island of Maui, atop a mountain, and Siding Spring, Australia, next to the world famous Anglo Australian Observatory, operate during usual school hours in the UK, which means night time in the locations where the scopes live. This is perfect for children in western Europe who wish to use research grade professional technology from the classroom, though the Faulkes scopes are also used by schools and researchers in Hawaii.
The type of scope/camera you choose to use, will ultimately also determine what it is you image. Some robotic scopes are configured with wide field large format CCD’s connected to fast, low focal ratio telescopes. These are perfect for creating large sky vistas encompassing nebulae and larger galaxies like Messier 31 in Andromeda. For imaging competitions like the Astronomy Photographer of the Year competition, these wide field scopes are perfect for the beautiful skyscapes they can create.
Scopes like the Faulkes Telescope North, even though it has a huge 2m (almost the same size as the one on the Hubble Space Telescope) mirror, is configured for smaller fields of view, literally only around 10 arcminutes, which will nicely fit in objects like Messier 51, the Whirpool Galaxy, but would take many separate images to image something like the full Moon (If Faulkes North were set up for that, which it’s not). It’s advantage is aperture size and immense CCD sensitivity. Typically our team using them is able to image a magnitude +23 moving object (comet or asteroid) in under a minute using a red filter too!
A field of view with a scope like the twin Faulkes scopes, which are owned and operated byLCOGT is perfect for smaller deep sky objects and my own interests which are comets and asteroids.Many other research projects such as exoplanets and the study of variable stars are conducted using these telescopes.Many schools start out imaging nebulae, smaller galaxies and globular clusters, with our aim at the Faulkes Telescope Project office, to quickly get students moving on to more science based work, whilst keeping it fun. For imagers, mosaic approaches are possible to create larger fields, but this obviously will take up more imaging and telescope slew time.
Each robotic system has its own set of learning curves, and each can suffer from technical or weather related difficulties, like any complex piece of machinery or electronic system. Knowing a bit about the imaging process to begin with, sitting in on other’s observing sessions on things like Slooh, all helps. Also make sure you know your target field of view/size on the sky (usually in either right ascension and declination) or some systems have a “guided tour mode” with named objects, and make sure you can be ready to move the scope to it as quickly as possible, to get imaging. With the commercial robotic scopes, time really is money.
Global Rent-A-Scope interface
Magazines like Astronomy Now in the UK, as well as Astronomy and Sky and Telescope in the United States and Australia are excellent resources for finding out more, as they regularly feature robotic imaging and scopes in their articles. Online forums like cloudynights.com and stargazerslounge.com also have thousands of active members, many of whom regularly use robotic scopes and can give advice on imaging and use, and there are dedicated groups for robotic astronomy like the Online Astronomical Society. Search engines will also give useful information on what is available as well.
To get access to them, most of the robotic scopes require a simple sign up process, and then the user can either have limited free access, which is usually an introductory offer, or just start to pay for time. The scopes come in various sizes and quality of camera, the better they are, usually the more you pay. For education and school users as well as astronomical societies, The Faulkes Telescope (for schools) and the Bradford Robotic scope both offer free access, as does the NASA funded Micro Observatory project. Commercial ones like iTelescope, Slooh and Lightbuckets provide a range of telescopes and imaging options, with a wide variety of price models from casual to research grade instrumentation and facilities.
So what about my own use of Robotic Telescopes?
Personally I use mainly the Faulkes North and South scopes, as well as the Liverpool La Palma Telescope. I have worked with the Faulkes Telescope Project team now for a few years, and it’s a real honour to have such access to research grade intrumentation. Our team also use the iTelescope network when objects are difficult to obtain using the Faulkes or Liverpool scopes, though with smaller apertures, we’re more limited in our target choice when it comes to very faint asteroid or comet type objects.
After having been invited to meetings in an advisory capacity for Faulkes, late in 2011 I was appointed pro am program manager, co-ordinating projects with amateurs and other research groups. With regards to public outreach I have presented my work at conferences and public outreach events for Faulkes and we’re about to embark on a new and exciting project with the European Space Agency whom I work for also as a science writer.
My use of Faulkes and the Liverpool scopes is primarily for comet recovery, measurement (dust/coma photometry and embarking on spectroscopy) and detection work, those icy solar system interlopers being my key interest. In this area, I co-discovered Comet C2007/Q3 splitting in 2010, and worked closely with the amateur observing program managed by NASA for comet 103P, where my images were featured in National Geographic, The Times, BBC Television and also used by NASA at their press conference for the 103P pre-encounter event at JPL.
The 2m mirrors have huge light grasp, and can reach very faint magnitudes in very little time. When attempting to find new comets or recover orbits on existing ones, being able to image a moving target at magnitude 23 in under 30s is a real boon. I am also fortunate to work alongside two exceptional people in Italy, Giovanni Sostero and Ernesto Guido, and we maintain a blog of our work, and I am a part of the CARA research group working on comet coma and dust measurements, with our work in professional research papers such as the Astrophysical Journal Letters and Icarus.
The Imaging Process
When taking the image itself, the process starts really before you have access to the scope. Knowing the field of view, what it is you want to achieve is critical, as is knowing the capabilities of the scope and camera in question, and importantly, whether or not the object you want to image is visible from the location/time you’ll be using it.
First thing I would do if starting out again is look through the archives of the telescope, which are usually freely available, and see what others have imaged, how they have imaged in terms of filters, exposure times etc, and then match that against your own targets.
Ideally, given that in many cases, time will be costly, make sure that if you’re aiming for a faint deep sky object with tenuous nebulosity, you don’t pick a night with a bright Moon in the sky, even with narrowband filters, this can hamper the final image quality, and that your choice of scope/camera will in fact image what you want it to. Remember that others may also want to use the same telescopes, so plan ahead and book early. When the Moon is bright, many of the commercial robotic scope vendors offer discounted rates, which is great if you’re imaging something like globular clusters maybe, which aren’t as affected by the moonlight (as say a nebula would be)
Forward planning is usually essential, knowing that your object is visible and not too close to any horizon limits which the scope may impose, ideally picking objects as high up as possible, or rising to give you plenty of imaging time. Once that’s all done, then following the scope’s imaging process depends on which one you choose, but with something like Faulkes, it’s as simple as selecting the target/FOV, slewing the scope, setting the filter, and then exposure time and then waiting for the image to come in.
The number of shots taken depends on the time you have. Usually when imaging a comet using Faulkes I will try to take between 10 and 15 images to detect the motion, and give me enough good signal for the scientific data reduction which follows. Always remember though, that you’re usually working with vastly superior equipment than you have at home, and the time it takes to image an object using your home setup will be a lot less with a 2m telescope. A good example is that a full colour high resolution image of something like the Eagle Nebula can be obtained in a matter of minutes on Faulkes, in narrowband, something which would usually take hours on a typical backyard telescope.
For imaging a non moving target, the more shots in full colour or with your chosen filter (Hydrogen Alpha being a commonly used one with Faulkes for nebula) you can get the better. When imaging in colour, the three filters on the telescope itself are grouped into an RGB set, so you don’t need to set up each colour band. I’d usually add a luminance layer with H-Alpha if it’s an emission nebula, or maybe a few more red images if it’s not for luminance. Once the imaging run is complete, the data is usually placed on a server for you to collect, and then after downloading the FITS files, combine the images using Maxim (or other suitable software) and then on in to something like Photoshop to make the final colour image. The more images you take, the better the quality of the signal against the background noise, and hence a smoother and more polished final shot.
Between shots the only thing that will usually change will be filters, unless tracking a moving target, and possibly the exposure time, as some filters take less time to get the requisite amount of light. For example with a H-Alpha/OIII/SII image, you typically image for a lot longer with SII as the emission with many objects is weaker in this band, whereas many deep sky nebula emit strongly in the H-Alpha.
The Image Itself
NGC 6302 taken by Thomas Mills High School with the Faulkes Telescope
As with any imaging of deep sky objects, don’t be afraid to throw away poor quality sub frames (the shorter exposures which go to make up the final long exposure when stacked). These could be affected by cloud, satellite trails or any number of factors, such as the autoguider on the telescope not working correctly. Keep the good shots, and use those to get as good a RAW stacked data frame as you can. Then it’s all down to post processing tools in products like Maxim/Photoshop/Gimp, where you’d adjust the colours, levels, curves and possibly use plug ins to sharpen up the focus, or reduce noise. If it’s pure science your interested in, you’ll probably skip most of those steps and just want good, calibrated image data (dark and flat field subtracted as well as bias)
The processing side is very important when taking shots for aesthetic value, it seems obvious, but many people can overdo it with image processing, lessening the impact and/or value of the original data. Usually most amateur imagers spend more time on processing than actual imaging, but this does vary, it can be from hours to literally days doing tweaks. Typically when processing an image taken robotically, the dark and flat field calibration are done. First thing I do is access the datasets as FITS files, and bring those in to Maxim DL. Here I will combine and adjust the histogram on the image, possible running multiple iterations of a de-convolution algorithm if the start points are not as tight (maybe due to seeing issues that night).
Once the images are tightened up and then stretched, I will save them out as FITS files, and using the free FITS Liberator application bring them in to Photoshop. Here, additional noise reduction and contrast/level and curve adjustments will be made on each channel, running a set of actions known as Noels actions (a suite of superb actions by Noel Carboni, one of the worlds foremost imaging experts) can also enhance the final individual red green and blue channels (and the combined colour one).
Then, I will composite the images using layers into a colour final shot, adjusting this for colour balance and contrast. Possibly running a focus enhancement plug in and further noise reduction. Then publish them via flickr/facebook/twitter and/or submit to magazines/journals or scientific research papers depending on the final aim/goals.
Serendipity can be a wonderful thing
I got in to this quite by accident myself…. In March 2010, I had seen a posting on a newsgroup that Comet C/2007 Q3, a magnitude 12-14 object at the time, was passing near to a galaxy, and would make an interesting wide field side by side shot. That weekend, using my own observatory, I imaged the comet over several nights, and noticed a distinct change in the tail and brightness of the comet over two nights in particular.
Comet C/2007 Q3. Credit: Nick Howes
A member of the BAA (British Astronomical Association), seeing my images, then asked if I would submit them for publication. I decided however to investigate this brightening a bit further, and as I had access to the Faulkes that week, decided to point the 2m scope at this comet, to see if anything unusual was taking place. The first images came in, and I immediately, after loading them in to Maxim DL and adjusting the histogram, noticed that a small fuzzy blob appeared to be tracking the comet’s movement just behind it. I measured the separation as only a few arc-seconds, and after staring at it for a few minutes, decided that it may have fragmented.
I contacted Faulkes Telescope control, who put me in touch with the BAA comet section director, who kindly logged this observation the same day. I then contacted Astronomy Now magazine, who leapt on the story and images and immediately went to press with it on their website. The following days the media furore was quite literally incredible.
Interviews with national newspapers, BBC Radio, Coverage on the BBC’s Sky at Night television show, Discovery Channel, Radio Hawaii, Ethiopia were just a few of the news/media outlets that picked up the story.. the news went global that an amateur had made a major astronomical discovery from his desk using a robotic scope. This then led on to me working with members of the AOP project with the NASA/University of Maryland EPOXI mission team on imaging and obtaining light curve data for comet 103P late in 2010, again which led to articles and images in National Geographic, The Times and even my images used by NASA in their press briefings, alongside images from the Hubble Space Telescope. Subscription requests to Faulkes Telescope Project as a result of my discoveries went up by hundreds of % from all over the world.
In summary
Robotic telescopes can be fun, they can lead to amazing things, this past year, a work experience student I was mentor for with the Faulkes Telescope Project, imaged several fields we’d assigned to her, where our team then found dozens of new and un-catalogued asteroids, and she also managed to image a comet fragmenting. Taking pretty pictures is fun, but the buzz for me comes with the real scientific research I am now engaged in, and it’s a pathway I aim to stay on probably for the rest of my astronomical lifetime. For students and people who don’t have the ability to either own a telescope due to financial or possibly location constraints, it’s a fantastic way to do real astronomy, using real equipment, and I hope, in reading this, you’re encouraged to give these fantastic robotic telescopes a try.
En route to the Red Planet, Mars rover Curiosity has experienced the strongest solar radiation storm since 2005. No need to be alarmed: Researchers say it’s all part of Curiosity’s job as a ‘stunt double’ for human astronauts.
In this edition, we talk about the non-discovery of faster-than-light neutrinos, the possibility of quakes on Mars, and explanation for the ridge on Iapetus, the 25th anniversary of SN1987A, and a steamy water world.
Tendrils of ice particles, called frazil, extend out into Antarctica's Mackenzie Bay. (NASA/EO-1 - ALI)
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Ghostly green tendrils drift out into Mackenzie Bay off the coast of eastern Antarctica in this image, acquired by NASA’s Earth-Observing (EO-1) satellite on Feb. 12, 2012.
The tendrils are made of fine particles of ice called frazil, the result of upwelling cold water from deep beneath the Amery ice shelf.
Sea water flowing in currents under the Amery ice shelf gets cooled to temperatures below freezing, the result of greater water pressures existing at depth. As some of the water rises and flows along the underside of the shelf toward the open ocean, it gradually encounters less pressure since the ice thickness decreases the further away from shore it extends.
When the supercold water approaches the surface where pressure is lowest, it instantly freezes, forming needle-like ice particles called frazil.
Only 3 -4 millimeters wide, the frazil crystals can still be concentrated enough to be visible from orbit as it drifts into the bay, flowing around icebergs as it is carried along by wind and currents. (The largest iceberg in the image is a little over 4 km/2.5 miles long.)
Eventually the warmer surface water that surrounds the southern continent melts the frazil, and the tendrils fade away.
Scheduled to fly for a year and only designed to last a year and a half, EO-1 celebrated its eleventh anniversary on November 21, 2011. During its time in orbit the satellite has accomplished far more than anyone dreamed, and its Earth-observing mission continues on. Read more on the EO-1 site here.
An artistic rendition of a nomad object wandering the interstellar medium. Credit: Greg Stewart / SLAC National Accelerator Laboratory
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Could the number of wandering planets in our galaxy – planets not orbiting a sun — be more than the amount of stars in the Milky Way? Free-floating planets have been predicted to exist for quite some time and just last year, in May 2011, several orphan worlds were finally detected. But now, the latest research concludes there could be 100,000 times more free-floating planets in the Milky Way than stars. Even though the author of the study, Louis Strigari from the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), called the amount “an astronomical number,” he said the math is sound.
“Even though this is a large number, it is actually consistent with the amount of mass and heavy elements in our galaxy,” Strigari told Universe Today. “So even though it sounds like a big number, it puts into perspective that there could be a lot more planets and other ‘junk’ out in our galaxy than we know of at this stage.”
And by the way, these latest findings certainly do not lend any credence to the theory of a wandering planet named Nibiru.
Several studies have suggested that our galaxy could perhaps be swarming with billions of these wandering “nomad” planets, and the research that actually found a dozen or so of these objects in 2011 used microlensing to identify Jupiter-sized orphan worlds between 10,000 and 20,000 light-years away. That research concluded that based on the number of planets identified and the area studied, they estimated that there could literally be hundreds of billions of these lone planets roaming our galaxy….literally twice as many planets as there are stars.
But the new study from Kavli estimates that lost, homeless worlds may be up to 50,000 times more common than that.
Using mathematical extrapolations and relying on theoretical variables, Strigari and his team took into account the known gravitational pull of the Milky Way galaxy, the amount of matter available to make such objects and how that matter might be distributed into objects ranging from the size of Pluto to larger than Jupiter.
“What we did was we put together the observations of what the galaxy is made of, what kind of elements it has, as well as how much mass there could possibly be that has been deduced from the gravitational pull from the stars we observed,” Stigari said via phone. “There are a couple of general bounds we used: you can’t have more nomads in the galaxy than the matter we observe, as well as you probably can’t have more than the amount of so called heavy elements than we observe in the galaxy (anything greater that helium on the periodic table).”
But any study of this type is limited by the lack of understanding of planetary formation.
“We don’t at this stage have a good theory that tells us how planets form,” Strigari said, “so it is difficult to predict from a straight theoretical model how many of these objects might be wandering around the galaxy.”
Strigari said their approach was largely empirical. “We asked how many could there possibly be, consistent with the broad constraints, that gives us a limit to how many these objects could possibly exist.”
So, in absence of any theory that really predicts how many of these things should exist, the estimate of 100,000 times the amount of stars in the Milky Way is an upper limit.
“A lot of times in science and astronomy, in order to learn what the galaxy and universe is made of, we first have to ask questions, what is it not made of, and so you start from an upper bound of how many of these planets there could be,”Strigari said. “Maybe when our data gets better we will start reducing this limit and then we can start learning from empirical observations and start having more constrained observations that go into your theoretical models.”
In other words, Strigari said, it doesn’t mean this is the final answer, but this is the state of our knowledge right now. “It kind of quantifies our ignorance, you could say,” he said.
A good count, especially of the smaller objects, will have to wait for the next generation of big survey telescopes, especially the space-based Wide-Field Infrared Survey Telescope and the ground-based Large Synoptic Survey Telescope, both set to begin operation in the early 2020s.
So, where did all these potential free range planets come from? One option is that they formed like stars, directly from the collapse of interstellar gas clouds. According to Strigari some were probably ejected from solar systems. Some research has indicated that ejected planets could be rather common, as planets tend to migrate over time towards the star, and as they plow through the material left over from the solar system’s formation, any other planet between them and their star will be affected. Phil Plait explained it as, “some will shift orbit, dropping toward the star themselves, others will get flung into wide orbits, and others still will be tossed out of the system entirely.”
Don’t worry – our own solar system is stable now, but it could have happened in the past, and some research has suggested we originally started out with more planets in our solar system, but some may have been ejected.
Of course, when discussing planets, the first thing to pop into many people’s minds is if a wandering planet could be habitable.
“If any of these nomad planets are big enough to have a thick atmosphere, they could have trapped enough heat for bacterial life to exist,” Strigari said. Although nomad planets don’t bask in the warmth of a star, they may generate heat through internal radioactive decay and tectonic activity.
As far as a Nibiru-type wandering world in our solar system right now the answer is no. There is no evidence or scientific basis whatsoever for such a planet. If it was out there and heading towards Earth for a December 21, 2012 meetup, we would have seen it or its effects by now.
The sprawling northern constellation of Draco is home to a monumental galactic merger which left a singular spectacle – NGC 5907. Surrounded by an ethereal garment of wispy star trails and currents of stellar material, this spiral galaxy is the survivor of a “clash of the dragons” which may have occurred some 8 to 9 billion years ago. Recent theory suggests galaxies of this type may be the product of a larger galaxy encountering a smaller satellite – but this might not be the case. Not only is NGC 5907 a bit different in some respects, it’s a lot different in others… and peculiar motion is just the beginning.
“If the disc of many spirals is indeed rebuilt after a major merger, it is expected that tidal tails can be a fossil record and that there should be many loops and streams in their halos. Recently Martínez-Delgado et al. (2010) have conducted a pilot survey of isolated spiral galaxies in the Local Volume up to a low surface brightness sensitivity of ~28.5 mag/arcsec2 in V band. They find that many of these galaxies have loops or streams of various shapes and interpret these structures as evidence of minor merger or satellite infall.” says J. Wang of the Chinese Academy of Sciences. “However, if these loops are caused by minor mergers, the residual of the satellite core should be detected according to numerical simulations. Why is it hardly ever detected?”
The “why” is indeed the reason NGC 5907 is being intensively studied by a team of six scientists of the Observatoire de Paris, CNRS, Chinese Academy of Sciences, National Astronomical Observatories of China NAOC and Marseille Observatory. Even though NGC 5907 is a member of a galactic group, there are no galaxies near enough to it to be causing an interaction which could account for its streamers of stars. It is truly a warped galaxy with gaseous and stellar disks which extend beyond the nominal cut-off radius. But that’s not all… It also has a peculiar halo which includes a significant fraction of metal enriched stars. NGC 5907 just doesn’t fit the patterns.
“For some of our models, we assume a star formation history with a varying global efficiency in transforming gas to stars, in order to preserve enough gas from being consumed before fusion.” explains the research team. “Although this fine-tuned star formation history may have some physical motivations, its main role is also to ensure the formation of stars after the emergence of the gaseous disc just after fusion.”
On left, the NGC 5907 galaxy. It is compared to the simulations, on right. Both cases show an edge-on galactic disk surrounded by giant loops of old stars, which are witnessing of a former, gigantic collision. (Jay Gabany, cosmotography.com / Observatoire de Paris / CNRS / Pythéas / NAOC)
Now enter the 32- and 196-core computers at the Paris Observatory center and the 680-core Graphic Processor Unit supercomputer of Beijing NAOC with the capability to run 50000 billion operations per second. By employing several state of the art, hydrodynamical, and numerical simulations with particle numbers ranging from 200 000 to 6 millions, the team’s goal was to show the structure of NGC 5907 may have been the result of the clash of two dragon-sized galaxies… or was it?
“The exceptional features of NGC 5907 can be reproduced, together with the central galaxy properties, especially if we compare the observed loops to the high-order loops expected in a major merger model.” says Wang. “Given the extremely large number of parameters, as well as the very numerous constraints provided by the observations, we cannot claim that we have already identified the exact and unique model of NGC 5907 and its halo properties. We nevertheless succeeded in reproducing the loop geometry, and a disc-dominated, almost bulge-less galaxy.”
In the meantime, major galaxy merger events will continue to be a top priority in formation research. “Future work will include modelling other nearby spiral galaxies with large and faint, extended features in their halos.” concludes the team. “These distant galaxies are likely similar to the progenitors, six billion years ago, of present-day spirals, and linking them together could provide another crucial test for the spiral rebuilding disc scenario.”
Who will really open up the space frontier? Just like the early days of airplanes, when ‘barnstormers’ traveled the country selling rides to the public, commercial space companies see the market as ripe with excited people who want to hitch a ride. In this video, scientists Alan Stern and Dan Durda describe the coming era of suborbital spaceflight and how it will open up great possibilities for researchers, educators, and the public beginning, perhaps, later this year.
“In all the 50 years of human spaceflight, there have been barely 500 people who’ve been launched into space,” says Stern. “We’re talking about launching thousands if not tens of thousands of space tourists every year and then researchers.”
