Contributing writer Tim Reyes is a former NASA software engineer and analyst who has supported development of orbital and lander missions to the planet Mars since 1992. He has an M.S. in Space Plasma Physics from University of Alabama, Huntsville.
The latest set of images from the long range imager, LORRI, on New Horizons now reveals surface features. At a press conference today, exhilarated NASA scientists discussed what the images are now suggesting. (Photo Credit: NASA/New Horizons)
Today, a trio of NASA scientists expressed their exhilaration with the set of new Pluto images released by the New Horizons team. “Land Ho” exclaimed Dr. Alan Stern as he first tried to explain where they are on their long journey. Nearly 500 years ago, not even Magellan on a three year journey to circumnavigate the Earth waited so long. A ten year journey is beginning to reveal fascinating new details of the dwarf planet Pluto, once the ninth planet of our Solar System. The latest images show surface features on Pluto suggesting polar caps.
A team effort that Dr. Weaver said called upon leading experts to resolve these newest details of Pluto’s surface. The inset at left shows schematically the geographic relationship of the two bodies as they orbit each other. The inset at right shows surface details at 3x maximum resolution. (Photo Credit: NASA/New Horizons)
The NASA press conference took place this afternoon, anchored by Dr. John Grunsfeld, Associate Administrator for the Science Mission Directorate who quickly turned over the discussion to the project scientist of the New Horizons mission, Dr. Alan Stern from the Southwest Research Institute of San Antonio, Texas. Grunsfeld began by stating NASA’s mission – “to explore, discover and inspire” and added that New Horizons is certainly executing these prime objectives.
Alan Stern started off by expressing his excitement with the latest results from the long range telescope on board New Horizons, LORRI, but emphasized he represents a team effort, the culmination of decades of work.
With just 11 weeks remaining and now 98% of the way to Pluto, the latest set of images from LORRI have now revealed details better than the best that was previously attainable – from the Hubble Space Telescope. Most incredible are indications of polar caps on the dwarf planet Pluto.
Dr. Stern, stated that the 25th Anniversay of the Hubble mission has also functioned as a segue to what is about to unfold from New Horizons. Until now, the best images of Pluto’s surface had been wrestled out of images from Hubble with computer processing. Yet, at the present distance New Horizons remains, his team is still relying on image processing to reveal these first surface details.
The gravitational tug of war of the unique binary system has forced both small bodies to forever face each other, similar to how our Moon always faces the Earth. (Photo Credit: NASA/New Horizons)
Dr. Stern stated how remarkable the Pluto-Charon system is. The earlier set of LORRI images from 2014 had shown the gravitational dance of the two small bodies. He stated that they are truly a binary system and a type we have never explored before. Pluto-Charon is a dual synchronous, tidally locked system. Dr. Stern explained that the Earth, close-in to the Sun, and their space probe New Horizons, now on its final approach, is viewing the sunlit side of Pluto and Charon.
The system is tipped over relative to its orbital plane around the Sun. Dr. Stern stated, “it is like watching Pluto rotate on a spit.” He said that we are nearly seeing it face on; similar to an observer hovering far above the Earth’s polar cap and looking down upon the Earth-Moon system. The orbits of the two bodies, as seen in the LORRI image sequence (animations, above), appear elliptical (oval), however, due to the extreme and final state of this binary system, the orbits are perfect circles; the eccentricities are zero! New Horizons is just approaching slightly off center.
Dr. Stern continued and explained how this latest set is now showing surface features on Pluto. The features “are suggesting the presence of polar caps”, however he also emphasized that it remains only suggestive until New Horizons can deliver more details, that is, higher resolution, color imagery from the Ralph imager and spectroscopic data (Ralph and Alice imaging spectrometers) to reveal composition. Dr. Stern turned over the press conference to Dr. Hal Weaver of John Hopkins’ Applied Physics Laboratory, the lead scientist for the LORRI instrument.
LORRI as Dr. Weaver explained is a state-of-the-art instrument. A fixed focus telescopic camera, functional from room temp down to 180 degees Fahrenheit below zero and utilizes an 8 inch primary mirror. The optical quality is extraordinary but the light gathering power is the same as one has in an amateur 8 inch telescope such as offered by Meade or Celestron. Still further, Dr. Weaver stated that LORRI is also extremely efficient and ligthweight, using less than 5 watts of power and weighing less than 20 lbs.
Dr. Weaver explained how the raw images from LORRI are presently little more than blotches of light, unspectacular at first glance, but with image processing, the details discussed today are revealed. The New Horizons team employed world-class experts in the technique of Image Deconvolution. It was again Hubble that spawned “a cottage industry”, over 20 years ago, including one expert – Todd Lauer of the National Optical Astronomy Observatory. Lauer and others took on the challenge of extracting quality imagery from the Hubble space telescope as it struggled with the astigmatism accidentally built into its optical system. A NASA Space Shuttle mission delivered and inserted a corrective lens into Hubble which has made its 25 years of service possible.
And the New Horizons’ processed images are now slightly better than Hubble and will just get much better. From the Q&A with the press. Weaver explained that while the images show more detail, Earth-based and Hubble images remain more light sensitive. Hubble sets an upper limit to the size of any remaining moons to be discovered. Weaver stated that by June, New Horizons’ LORRI will exceed the light sensitivity limits of Hubble. If there are more moons to be found, June will be the month.
Through the Q&A, Dr. Stern stated that an extraordinary aspect of Pluto’s atmosphere is that the planet’s atmosphere has continued to expand despite having passed a point in its orbit at which it should be freezing and condensing onto its surface. The atmosphere expanded 200 to 300% in the last decade. With the limited observations, Stern and other Pluto experts surmise that there is a lag in the climate akin to how our hottest months lag the beginning of Summer by a couple of months. Perhaps, a latent heat stored up in the near surface has continued to vaporize frozen gases thus building up the atmosphere more than first expected.
The composition of the dwarf planet’s surface was discussed. Most evident in Earth-based spectroscopy is that there is molecular nitrogen, carbon monoxide and methane. Stern stated they these species of molecules could explain the bright and dark spots of the surface. However, he emphasized that Pluto is composed of 70% rock by mass and the remaining is ice. Charon stands in remarkable contrast to Pluto. Chraon has primarily water and ammonia hydrates on its surface; no detectable atmosphere (so far). Charon’s appearance is much more uniform and bland. Altogether, Stern said that experts call this the Pluto-Charon dichotomy.
Dr. Stern near the end of the press conference restated that this is truly “my meet Pluto moment.” New Horizons is like a plane on its final approach to touchdown but New Horizons cannot slow down. There are no retro-rockets, no propulsion onboard that can slow down the probe on its trek to escape the gravity of the Sun. The probe will join the Pioneer and Voyager space probes as the only Human-made objects to leave the Solar System. With its final approach, with every day, Pluto and Charon closes in as Dr. Stern and Dr. Weaver explained, Pluto’s image will fill the full breadth of the imaging detector. Details on its surface will be equivalent to high resolution images of New York’s Manhattan (figure, above) showing details such as the ponds in Central Park.
To continue following the latest release of images from New Horizons go to http://www.nasa.gov/newhorizons/lorri-gallery.
What is up with the fossils on Mars? Found – a dinosaur skull on Mars? Discovered – a rat, squirrel or gerbil on Mars? In background of images from Curiosity, vertebrae from some extinct Martian species? And the human skull, half buried in photos from Opportunity Rover. All the images are made of stone from the ancient past and this is also what is called Pareidolia. They are figments of our imaginations, and driven by our interest to be there – on Mars – and to know that we are not alone. Altogether, they make a multitude of web pages and threads across the internet.
Rock-hounds and Martian paleontologists, if only amateur or retired, have found a bounty of fascinating rocks nestled among the rocks on Mars. There are impressive web sites dedicated to each’s eureka moment, dissemination among enthusiasts and presentation for discussion.
Be sure to explore, through the hyperlinks, many NASA, NASA affiliates’ and third party websites – embedded throughout this article. Also, links to specific websites are listed at the end of the article.
The centerpiece of recent interest is the dinosaur skull protruding from the Martian regolith, teeth still embedded, sparkling efferdent white. There are no sockets for these teeth. Dinosaur dentures gave this senior citizen a few extra good years. The jaw line of the skull has no joint or connection point with the skull. So our minds make up the deficits, fill in the blanks and we agree with others and convince ourselves that this is a fossilized skull. Who knows how this animal could have evolved differently.
But evolve it did – within our minds. Referencing online dictionaries [ref], “Pareidolia is the imagined perception of a pattern (or meaning) where it does not actually exist, as in considering the moon to have human features.” I must admit that I do not seek out these “discoveries” on Mars but I enjoy looking at them and there are many scientists at JPL that have the same bent. Mars never fails to deliver and caters to everyone, but when skulls and fossils are seen, it is actually us catering to the everyday images and wishes we hold in our minds.
The “Rat on Mars” (main figure, top center) is actually quite anatomically complete and hunkered down, having taken its final gasps of air, eons ago, as some cataclysmic event tore the final vestiges of Earth-like atmosphere off the surface. It died where it once roamed and foraged for … nuts and berries? Surprisingly, no nuts have been found. Blueberries – yes – they are plentiful on Mars and could have been an excellent nutritional source for rats; high in iron and possibly like their Earthly counterpart, high in anti-oxidants.
The blueberries were popularized by Dr. Steve Squyres, the project scientist of the Mars Exploration Rover (MER) mission. Discovered in Eagle crater and across Meridiani Planum, “Blueberries” are spherules of concretions of iron rich minerals from water. It is a prime chapter in the follow-the-water story of Mars. And not far from the definition of Pareidolia, Eagle Crater refers to the incredible set of landing bounces that sent “Oppy” inside its capsule, surrounded by airbags on a hole-in-one landing into that little crater.
Next, is the face of Mars of the Cydonia region (Images of Cydonia, Mars, NSSDC). As seen in the morphed images, above, the lower resolution Viking orbiter images presented Mars-o-philes clear evidence of a lost civilization. Then, Washington handed NASA several years of scant funding for planetary science, and not until Mars Global Surveyor, was the Face of Cydonia photographed again. The Mars Orbiter Camera from the University of Arizona delivered high resolution images that dismissed the notion of a mountain-sized carving. Nonetheless, this region of Mars is truly fascinating geologically and does not disappoint those in search of past civilizations.
And long before the face on Mars in Cydonia, there were the canals of Mars. Spotted by the Mars observer Schiaparelli, the astronomer described them as “channels” in his native language of Italian. The translation of the word turned to “Canals” in English which led the World to imagine that an advanced civilization existed on Mars. Imagine if you can for a moment, this world without Internet or TV or radio and even seldom a newspaper to read. When news arrived, people took it verbatim. Canals, civilizations – imagine how imaginations could run with this and all that actually came from it. It turns out that the canals or channels of Mars as seen with the naked eye were optical illusions and a form of Pareidolia.
So, as our imagery from Mars continues to return in ever greater detail and depth, scenes of pareidolia will fall to reason and we are left with understanding. It might seem sterile and clinical but its not. We can continue to enjoy these fascinating rocks – dinosaurs, rats, skulls, human figures – just as we enjoy a good episode of Saturday Night Live. And neither the science or the pareidolia should rob us of our ability to see the shear beauty of Mars, the fourth rock from the Sun.
In the article’s main image, what should not be included is the conglomerate rock on Mars. NASA/JPL scientists and geologists quickly recognized this as another remnant of Martian hydrologics – the flow of water and specifically, the bottom of a stream bed (NASA Rover Finds Old Streambed on Martian Surface). Truly a remarkable discovery and so similar to conglomerate rocks on Earth.
The combined observations from two generations of X-Ray space telescopes have now revealed a more complete picture of the nature of high-speed winds expelled from super-massive black holes. Scientist analyzing the observations discovered that the winds linked to these black holes can travel in all directions and not just a narrow beam as previously thought. The black holes reside at the center of active galaxies and quasars and are surrounded by accretion discs of matter. Such broad expansive winds have the potential to effect star formation throughout the host galaxy or quasar. The discovery will lead to revisions in the theories and models that more accurately explain the evolution of quasars and galaxies.
The observations were by the XMM-Newton and NuSTAR x-ray space telescopes of the quasar PDS 456. The observations were combined into the graphic, above. PDS 456 is a bright quasar residing in the constellation Serpens Cauda (near Ophiuchus). The data graph shows both a peak and a trough in the otherwise nominal x-ray emission profile as shown by the NuSTAR data (pink). The peak represents X-Ray emissions directed towards us (i.e.our telescopes) while the trough is X-Ray absorption that indicates that the expulsion of winds from the super-massive black hole is in many directions – effectively a spherical shell. The absorption feature caused by iron in the high speed wind is the new discovery.
X-Rays are the signature of the most energetic events in the Cosmos but also are produced from some of the most docile bodies – comets. The leading edge of a comet such as Rosetta’s P67 generates X-Ray emissions from the interaction of energetic solar ions capturing electrons from neutral particles in the comet’s coma (gas cloud). The observations of a super-massive black hole in a quasar billions of light years away involve the generation of x-rays on a far greater scale, by winds that evidently has influence on a galactic scale.
The study of star forming regions and the evolution of galaxies has focused on the effects of shock waves from supernova events that occur throughout the lifetime of a galaxy. Such shock waves trigger the collapse of gas clouds and formation of new stars. This new discovery by the combined efforts of two space telescope teams provides astrophysicists new insight into how star and galaxy formation takes place. Super-massive blackholes, at least early in the formation of a galaxy, can influence star formation everywhere.
Both the ESA built XMM-Newton and the NuSTAR X-Ray space telescope, a SMEX class NASA mission, use grazing incidence optics, not glass (refraction) or mirrors (reflection) as in conventional visible light telescopes. The incidence angle of the X-rays must be very shallow and consequently the optics are extended out on a 10 meter (33 foot) truss in the case of NuSTAR and over a rigid frame on the XMM-Newton.
The ESA built XMM-Newton was launched in 1999, an older generation design that used a rigid frame and structure. All the fairing volume and lift capability of the Ariane 5 launch vehicle was needed to put the Newton in orbit. The latest X-Ray telescope – NuSTAR – benefits from tens years of technological advances. The detectors are more efficient and faster and the rigid frame was replaced with a compact truss which required all of 30 minutes to deploy. Consequently, NuSTAR was launched on a Pegasus rocket piggybacked on a L-1011, a significantly smaller and less expensive launch system.
So now these observations are effectively delivered to the theorists and modelers. The data is like a new ingredient in the batter from which a galaxy and stars are formed. The models of galaxy and star formation will improve and will more accurately describe how quasars, with their active super-massive black-holes, transition into more quiescent galaxies such as our own Milky Way.
A storm is brewing, a battle of words and a war of the worlds. The Earth is not at risk. It is mostly a civil dispute, but it has the potential to influence the path of careers. In 2014, a Harvard led debate was undertaken on the question: Is Pluto a planet. The impact of the definition of planet and everything else is far reaching – to the ends of the Universe.
It could mean a count of trillions of planets in our galaxy alone or it means leaving the planet Pluto out of the count – designation, just a dwarf planet. This is a question of how to classify non-stellar objects. What is a planet, asteroid, comet, planetoid or dwarf planet? Does our Solar System have 8 planets or some other number? Even the count of planets in our Milky Way galaxy is at stake.
Not to dwell on the Harvard debate, let it be known that if given their way, the debates outcome would reset the Solar System to nine planets. For over eight years, the solar system has had eight planets. During the period 1807 to 1845, our Solar System had eleven planets. Neptune was discovered in 1846 and astronomers began to discover many more asteroids. They were eliminated from the club. This is very similar to what is now happening to Pluto-like objects – Plutoids. So from 1846 to 1930, there were 8 planets – the ones as defined today.
In 1930, a Kansas farm boy, Clyde Tombaugh, hired by Lowell Observatory discovered Pluto and for 76 years there were 9 planets. In the year 2006, the International Astronomical Union (IAU) took up a debate using a “democratic process” to accept a new definition of planet, define a new type – dwarf planet and then set everything else as “Small Bodies.” If your head is spinning with planets, you are not alone.
Two NASA missions were launched immediately before and after the IAU announcement took affect. The Dawn mission suddenly was to be launched to an asteroid and a dwarf planet and the New Horizons had rather embarked on a nine year journey to a planet belittled to a dwarf planet – Pluto. Principal Investigator, Dr. Alan Stern was upset. Furthermore, from the discoveries of the Kuiper mission and other discoveries, we now know that there are hundreds of billions of planets in our Milky Way galaxy; possibly trillions. The present definition excludes hundreds of billions of bodies from planethood status.
There are two main camps with de facto leaders. One camp has Dr. Mike Brown of Caltech and the other, Dr. Stern of the Southwest Research Institute (SWRI) as leading figures. A primary focus of Dr. Brown’s research is the study of trans-Neptunian objects while Dr. Sterns’s activities are many but specifically, the New Horizons mission which is 6 months away from its flyby of Pluto. Consider first the IAU Resolution 5A that its members approved:
(1) A “planet” is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighborhood around its orbit.
(2) A “dwarf planet” is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape2, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.
(3) All other objects, except satellites, orbiting the Sun shall be referred to collectively as “Small Solar System Bodies”.
This is our starting point – planet, dwarf planet, everything else. Consider “everything else”. This broad category includes meteoroids, asteroids, comets and planetesimals. Perhaps other small body types will arise as we look more closely at the Universe. Within the category, there is now a question of what is an asteroid and what is a comet. NASA’s flybys of comets and now ESA’s Rosetta at 67P/Churyumov–Gerasimenko are making the delineation between the two types difficult. The difference between a meteoroid and an asteroid is simply defined as less than or greater than one meter in size, respectively. So the Chelyabinsk event absolutely involved a small asteroid – about 20 meters in diameter. Planetesimals are small bodies in a solar nebula that are the building blocks of planets but they could lead to the creation of all the other types of small bodies.
Putting aside the question of “Small Bodies” and its sub-classes, what should be the definition of planet and dwarf planet? These are the two terms that demoted Pluto and raised Ceres to dwarf planet. It is also interesting to note how Resolution 5A is meant exclusively for our Solar System. In 2006, there were not thousands of exo-planets but just a few dozen extreme cases but nevertheless, the IAU did not choose to extend the definition to “stars” but rather just in reference to our pretty well known star, the Sun.
Recall Tim Allen’s movie, “The Santa Clause”. Clauses can cause a heap of trouble. The IAU has such a clause – Clause C which has caused much of the present controversy around the definition of planets. Clause (c) of Resolution 5A: “has cleared the neighborhood around its orbit.” This is the Pluto killer-clause which demoted it to dwarf planet status and reduced the number of planets in our solar system to eight. In a sense, the IAU chose to cauterize a wound, a weakness in the definitions, that if left unchanged, would have led to who knows how many planets in our Solar System.
The question of what is Pluto is open for public discussion so armed with enough knowledge to be dangerous, the following is my proposed alternative to the IAU’s that are arguably an improvement. The present challenge to Pluto’s status lies in the Kuiper Belt and Oort Cloud. Such belts or clouds are probably not uncommon throughout the galaxy. Plutoids are the 500 lb gorilla in the room.
This year, as touted by the likes of Planetary Society, Universe Today and elsewhere, is the year of the dwarf planet. How remarkable and surprising will the study of Ceres, Pluto and Charon by NASA spacecraft be? There is a strong possibility that after the celestial dust clears and data analysis is published, the IAU will take on the challenge again to better define what is a planet and everything else. It is impossible to imagine that the definitions can remain unchanged for long. Even now, there is sufficient information to independently assess the definitions and weigh in on the approaching debate. Anyone or any group – from grade schools to astronomical societies – can take on the challenge.
To encourage a debate and educate the public on the incredible universe that space probes and advanced telescopes are revealing, what follows is one proposed solution to what is a planet and everything else.
planet: is a celestial body that a) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium – nearly round shape, b) has a differentiated interior as a result of its formation c) has insufficient mass to fuse hydrogen in its core, d) does not match the definition of a moon.
minor planet: is a planet with a mass less than one Pluto mass and does not match the definition of a moon.
inter-Stellar (minor) planet: is a (minor) planet that is not gravitationally bound to a stellar object.
binary (minor) planet: is a celestial body that is orbiting another (minor) planet for which the system’s barycenter resides above the surface of both bodies.
These definitions solve some hairy dilemmas. For one, planets orbit around the majority of most stars in the Universe, not just the Sun as Resolution 5A was only intended. Planets can also exist gravitationally not bound to a star – the result of it own molecular cloud collapse without a star or expulsion from a stellar system. One could specify gravitational expulsion however, it is possible that explosive events occur that cause the disintegration of a star and its binding gravity or creates such an impulse that a planet is thrusted out of a stellar system. Having an atmosphere certainly doesn’t work. Astronomers are already anticipating Mars or Earth-sized objects deep in the Oort cloud that could have no atmosphere – frozen out and also despite their size, not be able to “clear their neighborhood.”
An animation (above) of Kepler mission planet candidates compiled by Jeff Thorpe. Kepler and other exoplanet projects are revealing that the properties of planets – orbits, size, temperature, makeup – are all extreme. Does Pluto represent one of those extremes – the smallest of planets? (Credit: NASA/Kepler, Jeff Thorp)
The need to create a lower-end limit to what is a planet reached a near fever pitch with the discovery of a Trans-Nepturnian Object (TNO) in 2005 that is bigger than Pluto – Eris. Dr. Michael Brown of Caltech and his team led in the discovery of bright large KBOs. There was not just Eris but many of nearly the same size as Pluto. So without clause (c), one would be left with a definition for planet that could allow the count of planets in our Solar System to rise into the hundreds maybe even thousands. This would become a rather unmanageable problem; the number of planets rising year after year and never settled and with no means to make reasonable comparisons between planetary systems throughout our galaxy and even the Universe.
Two more celestial body types follow that are proposed to round out the set.
moon: is a celestial body that a) orbits a (minor) planet and b) for which the barycenter of its orbit is below the surface of its parent (minor) planet.
This creates the possibility of a planet-moon system such that its barycenter is above the surface of the larger body. Pluto and Charon are the most prominent case in our Solar System. In such cases, if one body meets the criteria of a (minor)planet, then the other body can also be assessed to determine if it is also a (minor) planet and the pair as binary (minor) planets. If the primary body was a minor planet, it is possible that the barycenter could be above its surface but the secondary body does not meet all the criteria of a minor planet, specifically “differentiated interior”.
The definition of moon is compounded by the existence of, for example, asteroids with moons. For such objects, the smaller object is defined as a satellite.
Satellite: is a celestial body that a) orbits another celestial body, b) whose parent body is not a (minor) planet.
Another permissible term is moonlet which could be used to describe both very small moons such as those found in the Jovian and Saturn systems or a small body orbiting an asteroid or comet. Moonlet could replace satellite.
The discriminator between planet and moon is not mass but simply whether the celestial body orbits a (minor) planet and the barycenter resides inside the larger body. The definition of moon excludes the possibility of a planet orbiting another planet except in the special case of binary (minor) planet.
Defining a lower size limit to “Planet” is necessary to compare stellar systems and classify. A limit based on the body’s average surface pressure and temperature or the surface gravity could define a limit. While they could, they are not practical because of the extremes and diverse combinations of conditions. Strange objects would fall through the cracks.
Removing clause (c) – “has cleared the neighborhood around its orbit” – will avoid a future conflict such as a very low mass star with a plutoid-sized object or smaller, in a close orbit that has cleared its neighborhood.
Additionally, choosing to declare that Pluto becomes the “standard weight” that differentiates minor planet from planet sets a precedent. In an era in which computers measure and tally the state of our existence, setting this limit to include Pluto and return it as the ninth planet of our Solar System, is, in a small but significant way, a re-declaration of our humanity. Soon we will be challenged by artificial intelligence greater than ours; we are already have. Where will we stand our ground?
The consequences of this proposed set of definitions, makes Ceres a minor planet and no longer an asteroid. Many trans-Neptunian objects discovered in this century become minor planets. Of the known TNOs only Pluto and Eris meets the criteria of planet.The dwarf planet Eris would become the tenth planet. Makemake, Sedna, Quaoar, Orcus, Haumea would be minor planets. By keeping Pluto a planet and defining it as the standard bearer, only one new planet must be declared. Surely, more will be found, very distant, in odd elliptical and tilted orbits. The count of planets in our solar system could rise by 10, 20 maybe 50 and perhaps this would make the definition untenable but maybe not. So be it. New Horizons will fly by a dwarf planet in July but this should mark the beginning of the end of the present set of definitions.
This set of definitions defines a set of celestial bodies that consistently covers the spectrum of known bodies. There is the potential of exotic celestial objects that are spawned from cataclysmic events or from the unique conditions during the early epochs of the Universe or from remnants of old or dying stellar objects. Their discovery will likely trigger new or revised definitions but these definitions are a good working set for the time being. Ultimately, it is the decision of the IAU but the sharing of knowledge and the democratic processes that we cherish permits anyone to question and evaluate such definitions or proclamations.To all that share an interest in Pluto as or as not a planet raise your hand and be heard.
A video from 2014 by Kurz Gesagt describing the Pluto-Charon system. Is this a binary planet system or one of the “dwarf” variety?
My condolences to the friends and family of Tammy Plotner, the first regular contributing writer to Universe Today. Can’t we all relate to what drew Tammy to write about the Universe? She wrote outstanding articles for U.T.
Astronomers have reported the discovery of a star that passed within the outer reaches of our Solar System just 70,000 years ago, when early humans were beginning to take a foothold here on Earth. The stellar flyby was likely close enough to have influenced the orbits of comets in the outer Oort Cloud, but Neandertals and Cro Magnons – our early ancestors – were not in danger. But now astronomers are ready to look for more stars like this one.
Lead author Eric Mamajek from the University of Rochester and collaborators report in The Closest Known Flyby Of A Star To The Solar System (published in Astrophysical Journal on February 12, 2015) that “the flyby of this system likely caused negligible impact on the flux of long-period comets, the recent discovery of this binary highlights that dynamically important Oort Cloud perturbers may be lurking among nearby stars.”
The star, named Scholz’s star, was just 8/10ths of a light year at closest approach to the Sun. In comparison, the nearest known star to the Sun is Proxima Centauri at 4.2 light years.
While the internet has been rife with threads and accusations of a Nemesis star that is approaching the inner Solar System and is somehow being “hidden” by NASA, this small red dwarf star with a companion represents the real thing.
In 1984, the paleontologists David Raup and Jack Sepkoski postulated that a dim dwarf star, now widely known on the internet as the Nemesis Star, was in a very long period Solar orbit. The elliptical orbit brought the proposed star into the inner Solar System every 26 million years, causing a rain of comets and mass extinctions on that time period. By no coincidence, because of the sheer numbers of red dwarfs throughout the galaxy, Scholz’s star nearly fits such a scenario. Nemesis was proposed to be in a orbit extending 95,000 A.U. compared to Scholz’s nearest flyby distance of 50,000 A.U. Recent studies of impact rates on Earth, the Moon and Mars have discounted the existence of a Nemesis star (see New Impact Rate Count Lays Nemesis Theory to Rest, Universe Today, 8/1/2011)
But Scholz’s star — a real-life Oort Cloud perturber — was a small red dwarf star star with a M9 spectral classification. M-class stars are the most common star in our galaxy and likely the whole Universe, as 75% of all stars are of this type. Scholz’s is just 15% of the mass of our Sun. Furthermore, Scholz’s is a binary star system with the secondary being a brown dwarf of class T5. Brown Dwarfs are believed to be plentiful in the Universe but due to their very low intrinsic brightness, they are very difficult to discover … except, as in this case, as companions to brighter stars.
The astronomers reported that their survey of new astrometric data of nearby stars identified Scholz’s as an object of interest. The star’s transverse velocity was very low, that is, the stars sideways motion. Additionally, they recognized that its radial velocity – motion towards or away from us, was quite high. For Scholz’s, the star was speeding directly away from our Solar System. How close could Scholz’s star have been to our system in the past? They needed more accurate data.
The collaborators turned to two large telescopes in the southern hemisphere. Spectrographs were employed on the Southern African Large Telescope (SALT) in South Africa and the Magellan telescope at Las Campanas Observatory, Chile. With more accurate trangental and radial velocities, the researchers were able to calculate the trajectory, accounting for the Sun’s and Scholz’s motion around the Milky Way galaxy.
Scholz’s star is an active star and the researchers added that while it was nearby, it shined at a dimly of about 11th magnitude but eruptions and flares on its surface could have raised its brightness to visible levels and could have been seen as a “new” star by primitive humans of the time.
At present, Scholz’s star is 20 light years away, one of the 70 closest stars to our Solar System. However, the astronomers calculated, with a 98% certainty, that Scholz’s passed within 0.5 light years, approximately 50,000 Astronomical Units (A.U.) of the Sun.
An A.U. is the mean distance from the Earth to the Sun and 50,000 is an important mile marker in our Solar System. It is the outer reaches of the Oort Cloud where billions of comets reside in cold storage, in orbits that take hundreds of thousands of years to circle the Sun.
With this first extraordinary close encounter discovered, the collaborators of this paper as well as other researchers are planning new searches for “Nemesis” type stars. The Large Synoptic Survey Telescope (LSST) and other telescopes within the next decade will bring an incredible array of data sets that will uncover many more red dwarf, brown dwarf and possibly orphan planets roaming in nearby space. Some of these could likewise be traced to past or future near misses to the Sun and Earth system.
In March 2012, amateur astronomers began observing unusual clouds or plumes along the western limb of the red planet Mars. The plumes, in the southern hemisphere rose to over 200 kilometers altitude persisting for several days and then reappeared weeks later.
So a group of astronomers from Spain, the Netherlands, France, UK and USA have now reported their analysis of the phenomena. Their conclusions are inconclusive but they present two possible explanations.
Mars and mystery are synonymous. Among Martian mysteries, this one has persisted for three years. Our own planet, much more dynamic than Mars, continues to raise new questions and mysteries but Mars is a frozen desert. Frozen in time are features unchanged for billions of years.
In March 2012, the news of the observations caught the attention of Universe Today contributing writer Bob King. Reported on his March 22nd 2012 AstroBob blog page, the plumes or clouds were clear to see. The amateur observer, Wayne Jaeschke used his 14 inch telescope to capture still images which he stitched together into an animation to show the dynamics of the phenomena.
Now on February 16 of this year, a team of researchers led by Agustín Sánchez-Lavega of the University of the Basque Country in Bilbao, Spain, published their analysis in the journal Nature of the numerous observations, presenting two possible explanations. Their work is entitled: “An Extremely high-altitude plume seen at Mars morning terminator.”
The phenomena occurred over the Terra Cimmeria region centered at 45 degree south latitude. This area includes the tiger stripe array of magnetic fields emanating from concentrations of ferrous (iron) ore deposits on Mars; discovered by the Mars Global Surveyor magnetometer during low altitude aerobraking maneuvers at the beginning of the mission in 1998. Auroral events have been observed over this area from the interaction of the Martian magnetic field with streams of energetic particles streaming from the Sun. Sánchez-Lavega states that if these plumes are auroras, they would have to be over 1000 times brighter than those observed over the Earth.
The researchers also state that another problem with this scenario is the altitude. Auroras over Mars in this region have been observed up to 130 km, only half the height of the features. In the Earth’s field, aurora are confined to ionospheric altitudes – 100 km (60 miles). The Martian atmosphere at 200 km is exceedingly tenuous and the production of persistent and very bright aurora at such an altitude seems highly improbable.
The duration of the plumes – March 12th to 23rd, eleven days (after which observations of the area ended) and April 6th to 16th – is also a problem for this explanation. Auroral arcs on Earth are capable of persisting for hours. The Earth’s magnetic field functions like a capacitor storing charged particles from the Sun and some of these particles are discharged and produced the auroral oval and arcs. Over Mars, there is no equivalent capacitive storage of particles. Auroras over Mars are “WYSIWYG” – what you see is what you get – directly from the Sun. Concentrated solar high energy streams persisting for this long are unheard of.
The second explanation assessed by the astronomers is dust or ice crystals lofted to this high altitude. Again the altitude is the big issue. Martian dust storms will routinely lift dust to 60 km, still only one-third the height of the plumes. Martian dust devils will lift particles to 20 km. However, it is this second explanation involving ice crystals – Carbon Dioxide and Water – that the researchers give the most credence. In either instance, the particles must be concentrated and their reflectivity must account for the total brightness of the plumes. Ice crystals would be more easily transported to these heights, and also would be most highly reflective.
The paper also considered the shape of the plumes. The remarkable quality of modern amateur astrophotography cannot be overemphasized. Also the duration of the plumes was considered. By local noon and thereafter they were not observed. Again, the capabilities tendered by ground-based observations were unique and could not be duplicated by the present set of instruments orbiting Mars.
Still too many questions remain and the researchers state that “both explanations defy our present understanding of the Mars’ upper atmosphere.” By March 20th and 21st, the researchers summarized that at least 18 amateur astronomers observed the plume using from 20 to 40 cm telescopes (8 to 16 inch diameter) at wavelengths from blue to red. At Mars, the Mars Color Imager on MRO (MARCI) could not detect the event due to the 2 hour periodic scans that are compiled to make global images.
Of the many ground observations, the researchers utilized two sets from the venerable astrophotographers Don Parker and Daiman Peach. While observations and measurements were limited, the researchers analysis was exhaustive and included modeling assuming CO2, Water and dust particles. The researchers did find a Hubble observation from 1997 that compared favorably with the 2012 events and likewise modeled that event for comparison. However, Hubble results provided a single observation and the height estimate could not be narrowly constrained.
Explanation of these events in 2012 are left open-ended by the research paper. Additional observations are clearly necessary. With increased interest from amateurs and continued quality improvements plus the addition of the Maven spacecraft suite of instruments plus India’s Mars Orbiter mission, observations will eventually be gained and a Martian mystery solved to make way for yet another.
From the vantage point of a window in an insane asylum, Vincent van Gogh painted one of the most noted and valued artistic works in human history. It was the summer of 1889. With his post-impressionist paint strokes, Starry Night depicts a night sky before sunrise that undulates, flows and is never settled. Scientific discoveries are revealing a Cosmos with such characteristics.
Since Vincent’s time, artists and scientists have taken their respective paths to convey and understand the natural world. The latest released images taken by the European Planck Space Telescope reveals new exquisite details of our Universe that begin to touch upon the paint strokes of the great master and at the same time looks back nearly to the beginning of time. Since Van Gogh – the passage of 125 years – scientists have constructed a progressively intricate and incredible description of the Universe.
The path from Van Gogh to the Planck Telescope imagery is indirect, an abstraction akin to the impressionism of van Gogh’s era. Impressionists in the 1800s showed us that the human mind could interpret and imagine the world beyond the limitations of our five senses. Furthermore, optics since the time of Galileo had begun to extend the capability of our senses.
Mathematics is perhaps the greatest form of abstraction of our vision of the World, the Cosmos. The path of science from the era of van Gogh began with his contemporary, James Clerk Maxwell who owes inspiration from the experimentalist Michael Faraday. The Maxwell equations mathematically define the nature of electricity and magnetism. Since Maxwell, electricity, magnetism and light have been intertwined. His equations are now a derivative of a more universal equation – the Standard Model of the Universe. The accompanying Universe Today article by Ramin Skibba describes in more detail the new findings by Planck Mission scientists and its impact on the Standard Model.
The work of Maxwell and experimentalists such as Faraday, Michelson and Morley built an overwhelming body of knowledge upon which Albert Einstein was able to write his papers of 1905, his miracle year (Annus mirabilis). His theories of the Universe have been interpreted, verified time and again and lead directly to the Universe studied by scientists employing the Planck Telescope.
In 1908, the German physicist Max Planck, for whom the ESA telescope is named, recognized the importance of Einstein’s work and finally invited him to Berlin and away from the obscurity of a patent office in Bern, Switzerland.
As Einstein spent a decade to complete his greatest work, the General Theory of Relativity, astronomers began to apply more powerful tools to their trade. Edwin Hubble, born in the year van Gogh painted Starry Night, began to observe the night sky with the most powerful telescope in the World, the Mt Wilson 100 inch Hooker Telescope. In the 1920s, Hubble discovered that the Milky Way was not the whole Universe but rather an island universe, one amongst billions of galaxies. His observations revealed that the Milky Way was a spiral galaxy of a form similar to neighboring galaxies, for example, M31, the Andromeda Galaxy.
Einstein’s equations and Picasso’s abstraction created another rush of discovery and expressionism that propel us for another 50 years. Their influence continues to impact our lives today.
Telescopes of Hubble’s era reached their peak with the Palomar 200 inch telescope, four times the light gathering power of Mount Wilson’s. Astronomy had to await the development of modern electronics. Improvements in photographic techniques would pale in comparison to what was to come.
The development of electronics was accelerated by the pressures placed upon opposing forces during World War II. Karl Jansky developed radio astronomy in the 1930s which benefited from research that followed during the war years. Jansky detected the radio signature of the Milky Way. As Maxwell and others imagined, astronomy began to expand beyond just visible light – into the infrared and radio waves. Discovery of the Cosmic Microwave Background (CMB) in 1964 by Arno Penzias and Robert Wilson is arguably the greatest discovery from observations in the radio wave (and microwave) region of the electromagnetic spectrum.
Analog electronics could augment photographic studies. Vacuum tubes led to photo-multiplier tubes that could count photons and measure more accurately the dynamics of stars and the spectral imagery of planets, nebulas and whole galaxies. Then in the 1947, three physicists at Bell Labs , John Bardeen, Walter Brattain, and William Shockley created the transistor that continues to transform the World today.
For astronomy and our image of the Universe, it meant more acute imagery of the Universe and imagery spanning across the whole electromagnetic spectrum. Infrared Astronomy developed slowly beginning in the 1800s but it was solid state electronics in the 1960s when it came of age. Microwave or Millimeter Radio Astronomy required a marriage of radio astronomy and solid state electronics. The first practical millimeter wave telescope began operations in 1980 at Kitt Peak Observatory.
With further improvements in solid state electronics and development of extremely accurate timing devices and development of low-temperature solid state electronics, astronomy has reached the present day. With modern rocketry, sensitive devices such as the Hubble and Planck Space Telescopes have been lofted into orbit and above the opaque atmosphere surrounding the Earth.
Astronomers and physicists now probe the Universe across the whole electromagnetic spectrum generating terabytes of data and abstractions of the raw data allow us to look out into the Universe with effectively a sixth sense, that which is given to us by 21st century technology. What a remarkable coincidence that the observations of our best telescopes peering through hundreds of thousands of light years, even more so, back 13.8 billion years to the beginning of time, reveal images of the Universe that are not unlike the brilliant and beautiful paintings of a human with a mind that gave him no choice but to see the world differently.
Now 125 years later, this sixth sense forces us to see the World in a similar light. Peer up into the sky and you can imagine the planetary systems revolving around nearly every star, swirling clouds of spiral galaxies, one even larger in the sky than our Moon, and waves of magnetic fields everywhere across the starry night.
In Kubrick’s and Clark’s 2001 Space Odyssey, there was no question of “Boots or Bots”[ref]. The monolith had been left for humanity as a mileage and direction marker on Route 66 to the stars. So we went to Jupiter and Dave Bowman overcame a sentient machine, shut it down cold and went forth to discover the greatest story yet to be told.
Now Elon Musk, born three years after the great science fiction movie and one year before the last Apollo mission to the Moon has set his goals, is achieving milestones to lift humans beyond low-Earth orbit, beyond the bonds of Earth’s gravity and take us to the first stop in the final frontier – Mars – the destination of the SpaceX odyssey.
Ask him what’s next and nowhere on his bucket list does he have Disneyland or Disney World. You will find Falcon 9R, Falcon Heavy, Dragon Crew, Raptor Engine and Mars Colonization Transporter (MCT).
At the top of his working list is the continued clean launch record of the Falcon 9 and beside that must-have is the milestone of a soft landing of a Falcon 9 core. To reach this milestone, Elon Musk has an impressive array of successes and also failures – necessary, to-be-expected and effectively of equal value. His plans for tomorrow are keeping us on the edge of our seats.
CRS-5, the Cargo Resupply mission number 5, was an unadulterated success and to make it even better, Elon’s crew took another step towards the first soft landing of a Falcon core, even though it wasn’t entirely successful. Elon explained that they ran out of hydaulic fluid. Additionally, there is a slew of telemetry that his engineers are analyzing to optimize the control software. Could it have been just a shortage of fluid? Yes, it’s possible they could extrapolate the performance that was cut short and recognize the landing Musk and crew dreamed of.
The addition of the new grid fins to improve control both assured the observed level of success and also assured failure. Anytime one adds something unproven to a test vehicle, the risk of failure is raised. This was a fantastic failure that provided a treasure trove of new telemetry and the possibilities to optimize software. More hydraulic fluid is a must but improvements to SpaceX software is what will bring a repeatable string of Falcon core soft landings.
“Failure is not an option,” are the famous words spoken by Eugene Kranz as he’s depicted in the movie Apollo 13. Failure to Elon Musk and to all of us is an essential part of living. However, from Newton to Einstein to Hawking, the equations to describe and define how the Universe functions cannot show failure otherwise they are imperfect and must be replaced. Every moment of a human life is an intertwined array of success and failure. Referring only to the final frontier, in the worse cases, teams fall out of balance and ships fall out of the sky. Just one individual can make a difference between his or a team’s success. Failure, trial and error is a part of Elon’s and SpaceX’s success.
He doesn’t quote or refer to Steve Jobs but Elon Musk is his American successor. From Hyperloops, to the next generation of Tesla electric vehicles, Musk is wasting no time unloading ideas and making his dreams reality. Achieving his goals, making milestones depends also on bottom line – price and performance into profits. The Falcon rockets are under-cutting ULA EELVs (Atlas & Delta) by more than half in price per pound of payload and even more with future reuse. With Falcon Heavy he will also stake claim to the most powerful American-made rocket.
Musk’s success will depend on demand for his product. News in the last week of his investments in worldwide space-based internet service also shows his intent to promote products that will utilize his low-cost launch solutions. The next generation of space industry could falter without investors and from the likes of Musk, re-investing to build demand for launch and sustaining young companies through their start-up phases. Build it and they will come but take for granted, not recognize the fragility of the industry, is at your own peril.
So what is next in the SpaceX Odyssey? Elon’s sights remain firmly on the Falcon 9R (Reuse) and the Falcon Heavy. Nothing revolutionary on first appearance, the Falcon Heavy will look like a Delta IV Heavy on steroids. Price and performance will determine its success – there is no comparison. It is unclear what will become of the Delta IV Heavy once the Falcon Heavy is ready for service. There may be configurations of the Delta IV with an upper stage that SpaceX cannot match for a time but either way, the US government is likely to effectively provide welfare for the Delta and even Atlas vehicles until ULA (Lockheed Martin and Boeing’s developed corporation) can develop a competitive solution. The only advantage remaining for ULA is that Falcon Heavy hasn’t launched yet. Falcon Heavy, based on Falcon 9, does carry a likelihood of success based on Falcon 9’s 13 of 13 successful launches over the last 5 years. Delta IV Heavy has had 7 of 8 successful launches over a span of 11 years.
The convergence of space science and technology and science fiction in the form of Musk’s visions for SpaceX is linked to the NASA legacy beginning with NASA in 1958, accelerated by JFK in 1962 and landing upon the Moon in 1969. The legacy spans backward in time to Konstantin Tsiolkovsky, Robert Goddard, Werner Von Braun and countless engineers and forward through the Space Shuttle and Space Station era.
The legacy of Shuttle is that NASA remained Earth-bound for 30-plus years during a time that Elon Musk grew up in South Africa and Canada and finally brought his visions to the United States. With a more daring path by NASA, the story to tell today would have been Moon bases or Mars missions completed in the 1990s and commercial space development that might have outpaced or pale in comparison to today’s. Whether Musk would be present in commercial space under this alternate reality is very uncertain. But Shuttle retirement, under-funding its successor, the Ares I & V and Orion, cancelling the whole Constellation program, then creating Commercial Crew program, led to SpaceX winning a contract and accelerated development of Falcon 9 and the Dragon capsule.
SpaceX is not meant to just make widgets and profit. Mars is the objective and whether by SpaceX or otherwise, it is the first stop in humankind’s journey into the final frontier. Mars is why Musk developed SpaceX. To that end, the first focal point for SpaceX has been the development of the Merlin engine.
Now, SpaceX’s plans for Mars are focusing on a new engine – Raptor and not a Merlin 2 – which will operate on liquified methane and liquid oxygen. The advantage of methane is its cleaner combustion leaving less exhaust deposits within the reusable engines. Furthermore, the Raptor will spearhead development of an engine that will land on Mar and be refueled with Methane produced from Martian natural resources.
The Raptor remains a few years off and the design is changing. A test stand has been developed for testing Raptor engine components at NASA’s Stennis Space Center. In a January Reddit chat session[ref] with enthusiasts, Elon replied that rather than being a Saturn F-1 class engine, that is, thrust of about 1.5 million lbf (foot-lbs force), his engineers are dialing down the size to optimize performance and reliability. Musk stated that plans call for Raptor engines to produce 500,000 lbf (2.2 million newtons) of thrust. While smaller, this represents a future engine that is 3 times as powerful as the present Merlin engine (700k newtons/157 klbf). It is 1/3rd the power of an F-1. Musk and company will continue to cluster engines to make big rockets.
To achieve their ultimate goal – Mars colonization, SpaceX will require a big rocket. Elon Musk has repeatedly stated that a delivery of 100 colonists per trip is the present vision. The vision calls for the Mars Colonization Transporter (MCT). This spaceship has no publicly shared SpaceX concept illustrations as yet but more information is planned soon. A few enthusiasts on the web have shared their visions of MCT. What we can imagine is that MCT will become a interplanetary ferry.
The large vehicle is likely to be constructed in low-Earth orbit and remain in space, ferrying colonists between Earth orbit and Mars orbit. Raptor methane/LOX engines will drive it to Mars and back. Possibly, aerobraking will be employed at both ends to reduce costs. Raptor engines will be used to lift a score of passengers at a time and fill the living quarters of the waiting MCT vehicle. Once orbiting Mars, how does one deliver 100 colonists to the surface? With atmospheric pressure at its surface equivalent to Earth’s at 100,000 feet, Mars does not provide an Earth-like aerodynamics to land a large vehicle.
In 1952, Werner Von Braun in his book “Mars Projekt” envisioned an armada of ships, each depending on launch vehicles much larger than the Saturn V he designed a decade later. Like the invading Martians of War of the Worlds, the armada would rather converge on Mars and deploy dozens of winged landing vehicles that would use selected flat Martian plain to skid with passengers to a safe landing. For now, Elon and SpaceX illustrate the landing of Dragon capsules on Mars but it will clearly require a much larger lander. Perhaps, it will use future Raptors to land softly or possibly employ winged landers such as Von Braun’s after robotic Earth-movers on Mars have constructed ten or twenty mile long runways.
We wait and see what is next for Elon Musk’s SpaceX vision, his SpaceX Odyssey. For Elon Musk and his crew, there are no “wives” – Penelope and families awaiting their arrival on Mars. Their mission is more than a five year journey such as Star Trek. The trip to Mars will take the common 7 months of a Hohmann transfer orbit but the mission is really measured in decades. In the short-term, Falcon 9 is poised to launch again in early February and will again attempt a soft landing on a barge at sea. And later, hopefully, in 2015, the Falcon Heavy will make its maiden flight from Cape Canaveral’s rebuilt launch pad 39A where the Saturn V lifted Apollo 11 to the Moon and the first, last and many Space Shuttles were launched.
Not all comets break up as they vent and age, but for Rosetta’s comet 67P, the Rubber Duckie comet, a crack in the neck raises concerns. Some comets may just fizzle and uniformly expel their volatiles throughout their surfaces. They may become like puffballs, shrink some but remain intact.
Comet 67P is the other extreme. The expulsion of volatile material has led to a shape and a point of no return; it is destined to break in two. Songwriter Neil Sedaka exclaimed, “Breaking Up is Hard to Do,” but for comets this may be the norm. The fissure is part of the analysis in a new set of science papers published this week.
The images show a fissure spanning a few hundred meters across the neck of the two lobe comet. The fissure is just one of the many incredible features on Comet 67P and is reported in research articles released in the January 22, 2015, edition of the journal Science.
What it means is not certain, but Rosetta team scientists have stated that flexing of the comet might be causing the fissure. As the comet approaches the Sun, the solar radiation is raising the temperature of the surface material. Like all materials, the comet’s will expand and contract with temperature. And diurnal (daily) changes in the tidal forces from the Sun is a factor, too.
An image sequence from the Navcam of the Rosetta spacecraft (right) is shown beside a simulation. Further work on the interaction of comets with solar radiation will include computer models that utilize Rosetta data to reveal how comet nuclei evolve over time – over many orbits of the Sun- and break up. Peanut, rubber-duck, potatoes or just round-shaped comet nuclei likely result from combinations of rotation, changes in rotation, spin rate, composition and internal structure, as a nucleus interacts with the Sun over many orbits. (Credits: ESA/Rosetta, Illustration – J.Schmidt)
The crack, or fissure, could spell the beginning of the end for comet 67P/Churyumov–Gerasimenko. It is located in the neck area, in the region named Hapi, between the two lobes that make 67P appear so much like a Rubber Duck from a distance. The fissure could represent a focal point of many properties and forces at work, such as the rotation rate and axis – basically head over heels of the comet. The fissure lies in the most active area at present, and possibly the most active area overall. Though the Hapi region appears to receive nearly constant sunlight, at this time, Rosetta measurements (below) show otherwise – receiving 15% less sunlight than elsewhere.
Sunlight and heating are major factors and the neck likely experiences the greatest mechanical stresses – internal torques – from heating or tidal forces from the sun as it rotates and approaches perihelion. Rosetta scientists are still not certain whether 67P is two bodies in contact – a contact binary – or a shape that formed from material expelled about the neck area leading to its narrowing.
The Philae lander’s MUPUS thermal sensor measured a temperature of –153°C (–243°F) at the landing site, while VIRTIS, an instrument on the primary spacecraft Rosetta, has measured -70°C (-94°F) at present. These temperatures will rise as perihelion is reached on August 13, 2015, at a distance of 1.2432 A.U. (24% further from the Sun than Earth). At present – January 23rd – 67P is 2.486 A.U. from the Sun (2 1/2 times farther from the Sun than Earth). While not a close approach to the Sun for a comet, the Solar radiation intensity will increase by 4 times between the present (January 2014) and perihelion in August.
Stresses due to temperature changes from diurnal variations, the changing Sun angle during perihelion approach, from loss of material, and finally from changes in the tidal forces on a daily basis (12.4043 hours) may lead to changes in the fissure causing it to possibly widen or increase in length. Rosetta will continue escorting the comet and delivering images of the whole surface that will give Rosetta scientists the observations and measurements to determine 67P/Churyumov–Gerasimenko’s condition now and its fate in the longer term.
Stay tuned for a forthcoming article from UT’s writer Bob King about numerous Rosetta mission scientific findings published this week in the journal Science.
For DSCOVR – the payload of SpaceX’s next Falcon 9 launch, waiting one more week is a yawn. The Deep Space Climate Observatory (DSCOVR) spacecraft has withstood a delay of over 12 years. Word from Cape Canaveral is that the Air Force is delaying the launch of the next Falcon 9 until February 9th. Two days earlier, the launch date had been moved to January 31st.
Its original mission name could not be more noble, Triana – the name of Columbus’ sailor that first saw the New World. Then, it got tangled in the ignoble politics of space and climate change. Yet, if all goes well for the SpaceX Falcon 9 launch, the famous GoreSat satellite will be deployed and then immediately upstaged by what everyone agrees is a major milestone – returning a rocket’s 1st stage gently to Earth to reuse and to reduce the cost of space travel.
Remember GoreSAT? Better yet, do you recall the spacecraft Triana? They are one in the same. They are DSCOVR. The spacecraft was completed and ready to be shipped to Cape Canaveral in 2001. It was scheduled for launch on board NASA’s flagship, the Space Shuttle Columbia, on what became Columbia’s ill-fated last mission in January 2003. But DSCOVR had become the spoils of the victor. Bush had defeated Gore and the victor pulled the rug from under Triana.
The political story of the DSCOVR spacecraft is wrapped in the political tug of war over Climate Change. Senator Al Gore had long recognized the risks to humanity, to species extinction and destruction of ecosystems by the human-caused climate change. As vice president, in 1998, Gore proposed to NASA the concept that became Triana to monitor and better understand Climate Change. His political opponents labeled Triana “GoreSat”, and its constant downlink stream of “Whole Earth” images as “an expensive screensaver”.
The former Republican congressman from Texas, Dick Armey, referring to GoreSat, said, “This idea supposedly came from a dream. Well, I once dreamed I caught a 10-foot bass. But I didn’t call up the Fish and Wildlife Service and ask them to spend $30 million to make sure it happened.” This was the rash and risk beholding a spacecraft conceived by politicians. However, while political egos were bruised, Triana, now DSCOVR, was never damaged and was placed into cold storage and for two Bush terms was bathed in pure nitrogen gas to minimize any damage to electronics.
While Solar radiation causes skin damage and melanoma, Solar eruptions – Coronal Mass Ejections (CME) have a global impact – disruption of electrical power grids and damage to Earth orbiting spacecraft. Just as California expects the “big one” and plans for large quakes, DSCOVR is meant to give the Earth an early warning system. According to NOAA and NASA, without monitoring upwind, the big one will cost upwards of $2 trillion in damages including a breakdown of power grids and major satellite systems that the world depends on for transportation, GPS, telecommunications and commerce. In time, a massive CME will happen.
As sure as the Sun rises every morning, DSCOVR was pulled out of storage in November 2008. Despite the years of idle time and technological advances passing it by, DSCOVR still holds an excellent array of instruments. The National Research Council was commissioned to analyze and reported to Congress that Triana was “Strong and scientifically vital.” Beginning in 2009, the instruments were re-certified for flight re-integrated onto the spacecraft bus. Filters were replaced on the 30 cm (12 inch) telescopic camera.
DSCOVR’s Earth Polychromatic Imaging Camera (EPIC) will provide a first of its kinds continuous stream of 8 km resolution global images of the rotating sunlit Earth. The images in 3 bands are in contrast to the future geostationary GOES-R weather satellites (a pair) which will have a 0.5 and 1 km resolution images but only for the western hemisphere. DSCOVR will pair up with ACE to monitor particles and fields streaming from the Sun towards the Earth, 1.5 million km (1 million miles) away.
Three particle and fields instruments will monitor electrons and ions – a top-hat electron electrostatic analyzer and a Farday Cup ion detector; the same type of detectors that were recently flown on the Philae lander to comet 67P. The third Plasma instrument is a pair of fluxgate magnetometers designed and constructed by the late Dr. Mario Acuna’s magnetometer team at Goddard Spaceflight Center. Lastly, targeting its interest in Climate Change, the NiStar instrument developed at Ball Aerospace “is a cavity radiometer designed to measure the absolute, spectrally integrated irradiance reflected and emitted from the entire sunlit face of the Earth”, as stated in NOAA documentation.
DSCOVR now becomes the legacy to a long line of Solar-Terrestial monitoring spacecraft. If you recall last August 10th, the spacecraft ISEE-3 flew past the Earth after over 20 years out of contact and 35 years in space. ISEE-3 became the first vehicle to utilize the Sun-Earth Lagrangian point 1 (L1) to monitor the Solar wind. Several vehicles followed, specialized probes even clusters were developed to understand the complex interaction between the Sun and the Earth’s magnetic field and atmosphere.
DSCOVR will join two existing vehicles – the aging Advanced Composition Explorer (ACE) and the Solar Dynamics Observatory (SDO). Altogether, a next generation of monitoring and, as NOAA emphasizes, development of space weather forecasting and a warning system will evolve from addition of DSCOVR. This also represents SpaceX first contracted launch in the Orbital/Suborbital Program (OSP)-3 NASA program. The second contracted (OSP)-3 launch will be atop the Falcon Heavy expected later in 2015.