Animation of images acquired by New Horizons on Jan. 27–Feb. 8, 2015. Hydra is in the yellow square, Nix is in the orange. (Credit: NASA/Johns Hopkins APL/Southwest Research Institute.)
Now on the final leg of its journey to distant Pluto the New Horizons spacecraft has been able to spot not only the dwarf planet and its largest moon Charon, but also two of its much smaller moons, Hydra and Nix – the latter for the very first time!
The animation above comprises seven frames made of images acquired by New Horizons from Jan. 27 to Feb. 8, 2015 while the spacecraft was closing in on 115 million miles (186 million km) from Pluto. Hydra is noted by a yellow box and Nix is in the orange. (See a version of the animation with some of the background stars and noise cleared out here.)
“Professor Tombaugh’s discovery of Pluto was far ahead its time, heralding the discovery of the Kuiper Belt and a new class of planet. The New Horizons team salutes his historic accomplishment.”
– Alan Stern, New Horizons PI, Southwest Research Institute
Launched Jan. 19, 2006, New Horizons will make its closest pass of Pluto and Charon on July 14 of this year. It is currently 32.39 AU from Earth – over 4.84 billion kilometers away.
“It’s thrilling to watch the details of the Pluto system emerge as we close the distance to the spacecraft’s July 14 encounter,” said New Horizons science team member John Spencer from the Southwest Research Institute (SwRI). “This first good view of Nix and Hydra marks another major milestone, and a perfect way to celebrate the anniversary of Pluto’s discovery.”
Along with the distance between Earth and Pluto, New Horizons is also bridging the gap of history: a portion of Mr. Tombaugh’s ashes are being carried aboard the spacecraft, as well as several historic mementos.
Annotated and unannotated versions of the LORRI images from Feb. 8 (top and bottom); the right side has had Pluto’s glare and additional background stars removed. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)
Each frame in the animation is a combination of five 10-second images taken with New Horizons’ Long-Range Reconnaissance Imager (LORRI) using a special mode that increases sensitivity at the expense of resolution. Celestial north is inclined 28 degrees clockwise from the “up” direction in these images.
The dark streaks are a result of overexposure on the digital camera’s sensitive detector.
Pluto and its moons, most of which were discovered while New Horizons was in development and en route. Charon was found in 1978, Nix and Hydra in 2005, Kerberos in 2011, and Styz in 2012. Credit: NASA/HST
Pluto has a total of five known moons: Charon, Hydra, Nix, Styx, and Kerberos. Pluto and Charon are within the glare of the image exposures and can’t be resolved separately, and Styx and Kerberos are too dim to be detected yet. But Hydra and Nix, each around 25–95 miles (40–150 km) in diameter, could be captured on camera.
More precise measurements of these moons’ sizes – and whether or not there may be even more satellites in the Pluto system – will be determined as New Horizons approaches its July flyby date.
Pluto and Charon, the largest of Pluto's five known moons, seen Jan. 25 and 27, 2015, through the telescopic Long-Range Reconnaissance Imager (LORRI) on NASA's New Horizons spacecraft. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.
Here we go! New Horizons is now on approach and today – on the anniversary of Pluto discoverer Clyde Tombaugh’s birth – the spacecraft has sent back its first new images of the Pluto system. The images aren’t Earth-shattering (Pluto-shattering?) but they do represent the mission is closing in on its target, and will allow the New Horizons engineers to precisely aim the spacecraft as it continues its approach.
The photos were taken with the telescopic Long-Range Reconnaissance Imager (LORRI) on January 25 and 27, 2015.
“Pluto is finally becoming more than just a pinpoint of light,” said Hal Weaver, New Horizons project scientist. “LORRI has now resolved Pluto, and the dwarf planet will continue to grow larger and larger in the images as New Horizons spacecraft hurtles toward its targets. The new LORRI images also demonstrate that the camera’s performance is unchanged since it was launched more than nine years ago.”
A comparison of images of Pluto and its large moon Charon, taken in July 2014 and January 2015. Between takes, New Horizons had more than halved its distance to Pluto, from about 264 million miles (425 million kilometers) to 126 million miles (203 million kilometers). Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.
New Horizons was about 203 million kilometers (126 million miles) away from Pluto when it began taking images. Pluto appears as a pixelated smudge, and New Horizons is only close enough so that just Pluto and its largest moon, Charon are visible. In this current view from LORRI, Pluto is about 2 pixels and Charon is 1, compared to 1 pixel and 0.5 pixels last July. The images were magnified four times to make Pluto and Charon more visible.
NASA says that over the next few months, LORRI will take hundreds of pictures of Pluto, against a starry backdrop, to refine the team’s estimates of New Horizons’ distance to Pluto. As in these first images, the Pluto system will resemble little more than bright dots in the camera’s view until late spring. However, mission navigators can still use such images to design course-correcting engine maneuvers to direct the spacecraft for a more precise approach. The first such maneuver based on these optical navigation images, or OpNavs, is scheduled for March 10.
The image of Pluto and its moon Charon, taken by NASA’s New Horizons spacecraft, was magnified four times to make the objects more visible. Over the next several months, the apparent sizes of Pluto and Charon, as well as the separation between them, will continue to expand in the images. Image Credit: NASA/JHU APL/SwRI
Closest approach for the spacecraft will be on July 14.
These first images represent a milestone.
“These images of Pluto, clearly brighter and closer than those New Horizons took last July from twice as far away, represent our first steps at turning the pinpoint of light Clyde saw in the telescopes at Lowell Observatory 85 years ago, into a planet before the eyes of the world this summer,” said Alan Stern, New Horizons principal investigator. “This is our birthday tribute to Professor Tombaugh and the Tombaugh family, in honor of his discovery and life achievements — which truly became a harbinger of 21st century planetary astronomy.”
During its flyby, New Horizons will be characterizing the global geology and topography of Pluto and Charon, mapping their surface compositions and temperatures, examining Pluto’s atmospheric composition and structure, studying Pluto’s smaller moons, and searching for new moons and rings.
The 33 largest objects in our Solar System, ordered by mean radius, using the best images available as of January, 2015. Credit and copyright: Radu Stoicescu.
Lined up like familiar faces in your high school yearbook, here are images of the 33 largest objects in the Solar System, ordered in size by mean radius. Engineer Radu Stoicescu put this great graphic together, using the highest resolution images available for each body. Nine of these objects have not yet been visited by a spacecraft. Later this year, we’ll visit three of them and be able to add better images of Ceres, Pluto and Charon. It might be a while until the remaining six get closeups.
“This summer, for the first time since 1989,” Stoicescu noted on reddit, “we will add 3 high resolution pictures to this collection, then, for the rest of our lives, we are not going to see anything larger than 400 km in high definition for the first time. It is sad and exciting at the same time.”
Dawn will enter orbit at Ceres approximately March 6, 2015, four months before New Horizons flies past Pluto and Charon.
But a comprehensive Solar System yearbook might never be completed. Not only will there likely be new dwarf planets discovered in the Kuiper Belt, uUnless things change in the budgetary and planetary missions departments for any of the world’s space agencies, the remaining six unvisited objects in the graphic above will likely remain as “fuzzy dots” for the rest of our lives.
If you like the graphic above, you can see more imagery and space discussions at Stoicescu’s reddit page.
For more Solar System yearbook-like imagery, Emily Lakdawalla has also created some wonderful graphics/montages of our Solar System, like this one:
Every round object in the solar system under 10,000 kilometers in diameter, to scale. Montage by Emily Lakdawalla. Data from NASA / JPL and SSI, processed by Gordan Ugarkovic, Ted Stryk, Bjorn Jonsson, and Emily Lakdawalla.
As Emily wrote in the accompanying blog post, “Just look at all of these worlds, and think about how much of the solar system we have yet to explore. Think about how much we have to learn by orbiting, and maybe even landing on, those planet-sized moons. Think about how Pluto isn’t the end of the planets, it’s the start of a whole new part of the solar system that we’ve never seen before, and how seeing Charon is going to clue us in to what’s happening on a dozen other similar-sized, unvisitably far worlds.”
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At least two unknown planets could exist in our solar system beyond Pluto. / Credit: NASA/JPL-Caltech.
Could there be another Pluto-like object out in the far reaches of the Solar System? How about two or more?
Earlier this week, we discussed a recent paper from planet-hunter Mike Brown, who said that while there aren’t likely to be any bright, easy-to-find objects, there could be dark ones “lurking far away.” Now, a group of astronomers from the UK and Spain maintain at least two planets must exist beyond Neptune and Pluto in order to explain the orbital behavior of objects that are even farther out, called extreme trans-Neptunian objects (ETNO).
The presently known largest small bodies in the Kuiper Belt are likely not to be surpassed by any future discoveries. This is the conclusion of Dr. Michael Brown, et al. (Illustration Credit: Larry McNish, Data: M.Brown)
We do know that Pluto shares its region Solar System with more than 1500 other tiny, icy worlds along with likely countless smaller and darker ones that have not yet been detected.
In two new paper published this week, scientists at the Complutense University of Madrid and the University of Cambridge noted that the most accepted theory of trans-Neptunian objects is that they should orbit at a distance of about 150 AU, be in an orbital plane – or inclination – similar to the planets in our Solar System, and they should be randomly distributed.
But that differs from what is actually observed. What astronomers see are groupings of objects with widely disperse distances (between 150 AU and 525 AU) and orbital inclinations that vary between 0 to 20 degrees.
“This excess of objects with unexpected orbital parameters makes us believe that some invisible forces are altering the distribution of the orbital elements of the ETNO,” said Carlos de la Fuente Marcos, scientist at UCM and co-author of the study, “ and we consider that the most probable explanation is that other unknown planets exist beyond Neptune and Pluto.”
He added that the exact number is uncertain, but given the limited data that is available, their calculations suggest “there are at least two planets, and probably more, within the confines of our solar system.”
In their studies, the team analyzed the effects of what is called the ‘Kozai mechanism,’ which is related to the gravitational perturbation that a large body exerts on the orbit of another much smaller and further away object. They looked at how the highly eccentric comet 96P/Machholz1 is influenced by Jupiter (it will come near the orbit of Mercury in 2017, but it travels as much as 6 AU at aphelion) and it may “provide the key to explain the puzzling clustering of orbits around argument of perihelion close to 0° recently found for the population of ETNOs,” the team wrote in one of their papers.
The discovery images of 2012 VP113. Each one was taken about two hours apart on Nov. 5, 2012. Behind the object, you can see background stars and galaxies that remained still (from Earth’s perspective) in the picture frame. Credit: Scott S. Sheppard: Carnegie Institution for Science
They also looked at the dwarf planet discovered last year called 2012 VP113 in the Oort cloud (its closest approach to the Sun is about 80 astronomical units) and how some researchers say it appears its orbit might be influenced by the possible presence of a dark and icy super-Earth, up to ten times larger than our planet.
“This Sedna-like object has the most distant perihelion of any known minor planet and the value of its argument of perihelion is close to 0°,” the team writes in their second paper. “This property appears to be shared by almost all known asteroids with semimajor axis greater than 150 au and perihelion greater than 30 au (the extreme trans-Neptunian objects or ETNOs), and this fact has been interpreted as evidence for the existence of a super-Earth at 250 au. In this scenario, a population of stable asteroids may be shepherded by a distant, undiscovered planet larger than the Earth that keeps the value of their argument of perihelion librating around 0° as a result of the Kozai mechanism.”
Of course, the theory put forth in two papers published by the team goes against the predictions of current models on the formation of the Solar System, which state that there are no other planets moving in circular orbits beyond Neptune.
But the team pointed to the recent discovery of a planet-forming disk around the star HL Tauri that lies more than 100 astronomical units from the star. HL Tauri is more massive and younger than our Sun and the discovery suggests that planets can form several hundred astronomical units away from the center of the system.
The team based their analysis by studying 13 different objects, so what is needed is more observations of the outer regions of our Solar System to determine what might be hiding out there.
The presently known largest trans-Neptunian objects (TNO) - are likely to be surpassed by future discoveries. Which of these trans-Neptunian objects (TNO) would you call planets and which "dwarf planets"? (Illustration Credit: Larry McNish, Data: M.Brown)
The self-professed “Pluto Killer” is at it again. Dr. Michael Brown is now reminiscing about the good old days when one could scour through sky survey data and discover big bright objects in the Kuiper Belt. In his latest research paper, Brown and his team have concluded that those days are over.
Ten years ago, Brown discovered what is now known as the biggest Kuiper Belt object – Eris. Brown’s team found others that rivaled Pluto in size and altogether, these discoveries led to the demotion of Pluto to dwarf planet. Now, using yet another sky survey data set but with new computer software, Brown says that its time to move on.
Instigators of the big heist – Rabinowitz, Brown and Trujillo, left to right. The researchers co-discovered dozens of Kuiper Belt objects (KBO) including nine of the ten largest KBOs including the largest, Eris.
Like the famous Bugs Bunny cartoon, its no longer Rabbit Season or Duck Season and as Bugs exclaims to Elmer Fudd, there is no more bullets. Analyzing seven years worth of data, Brown and his team has concluded we are fresh out of Pluto or Charon-sized objects to be discovered in the Kuiper Belt. But for Dr. Brown, perhaps it now might be Oort Cloud season.
His latest paper, A Serendipitous All Sky Survey For Bright Objects In The Outer Solar System, in pre-print, describes the completion of analysis of two past sky surveys covering the northern and southern hemisphere down to 20 degrees in Galactic latitude. Using revised computer software, his team scoured through the data sets from the Catalina Sky Survey (CSS) and the Siding Spring Survey (SSS). The surveys are called “fast cadence surveys” and they primarily search for asteroids near Earth and out to the asteroid belt. Instead Brown’s team used the data to look at image frames spaced days and months apart.
Update: In a Twitter communique, Dr. Brown stated, “I would say we’re out of BRIGHT ones, not big ones. Could be big ones lurking far away!” His latest work involved a southern sky survey (SSS) to about magnitude 19 and the northern survey (CSS) to 21. Low albedo (dark) and more distant KBOs might be lurking beyond the detectability of these surveys that are in the range of Charon to Pluto in size.
Animation showing the movement of Eris on the images used to discover it. Eris is indicated by the arrow. The three frames were taken over a period of three hours. More images over several weeks were necessary to determine its orbit.(Credit: Brown, et al.)
Objects at Kuiper Belt distances move very slowly. For example, Pluto orbits the Sun at about 17,000 km/hr (11,000 mph), taking 250 years to complete one orbit. These are speeds that are insufficient to maintain ven a low-Earth orbit. Comparing two image frames spaced just hours apart will find nearby asteroids moving relative to the star fields but not Kuiper belt objects. So using image frames spaced days, weeks or even months apart, they searched again. Their conclusion is that all the big Kuiper belt objects have been found.
The only possibility of finding another large KBO lies in a search of the galactic plane which is difficult due to the density of Milky Way’s stars in the field of view. The vast number of small bodies in the Kuiper belt and Oort Cloud lends itself readily to statistical analysis. Brown states that there is a 32% chance of finding another Pluto-sized object hiding among the stars of the Milky Way.
Artists concept of the view from Eris with Dysnomia in the background, looking back towards the distant sun. Credit: Robert Hurt (IPAC)
Dr. Brown also released a blog story in celebration of the discovery of the largest of the Kuiper Belt objects, Eris, ten years ago last week. Ten years of Eris, reminisces about the great slew of small body discoveries by Dr. Brown, Dr. Chad Trujillo of Gemini Observatory and Dr. David Rabinowitz of Yale Observatory.
Brown encourages others to take up this final search right in the galactic plane but apparently his own intentions are to move on. What remains to be seen — that is, to be discovered — are hundreds of large “small” bodies residing in the much larger region of the Oort Cloud. These objects are distributed more uniformly throughout the whole spherical region that the Cloud defines around the Sun.
Furthermore, Dr. Brown maintains that there is a good likelihood that a Mars or Earth-sized object exists in the Oort Cloud.
Small bodies within our Solar System along with exo-planets are perhaps the hottest topics and focuses of study in Planetary Science at the moment. Many graduate students and seasoned researchers alike are gravitating to their study. There are certainly many smaller Kuiper belt objects remaining to be found but more importantly, a better understanding of their makeup and origin are yet to be revealed.
Artist’s concept of the Dawn spacecraft at the protoplanet Ceres Illustration of Dawn’s approach phase and RC3 orbit This artist’s concept of NASA’s Dawn spacecraft shows the craft orbiting high above Ceres, where the craft will arrive in early 2015 to begin science investigations. (Image credit: NASA/JPL-Caltech)
Presently, the Dawn spacecraft is making final approach to the dwarf planet Ceres in the Asteroid belt. The first close up images of Ceres are only a few days away as Dawn is now just a couple of 100 thousand miles away approaching at a modest speed. And much farther from our home planet, scientists led by Dr. Alan Stern of SWRI are on final approach to the dwarf planet Pluto with their space probe, New Horizons. The Pluto system is now touted as a binary dwarf planet. Pluto and its moon Charon orbit a common point (barycenter) in space that lies between Pluto and Charon.
So Dr. Brown and team exits stage left. No more dwarf planets – at least not soon and not in the Kuiper belt. Will that upstage what is being called the year of the Dwarf Planet?
But next up for close inspection for the first time are Ceres, Pluto and Charon. It should be a great year.
The relative sizes of the inner Solar System, Kuiper Belt and the Oort Cloud. (Credit: NASA, William Crochot)
This object is a stowaway on board New Horizons. Credit: JHU/APL
The New Horizons spacecraft is now just a few months away from its encounter with Pluto and the Kuiper Belt, arriving in July, 2015. Back in 2008, the New Horizons team revealed the secret stowaways they had hidden on board the spacecraft. Nine objects (can you guess why there are nine?!) were attached and sent along on the ten-year journey to the outer reaches of our Solar System. Believe it or not, included in the items are one actual person, and parts of several thousands of other people…
Here’s the complete list:
1. One actual person. Well, part of an actual person. A portion of Pluto discoverer Clyde Tombaugh’s ashes were put in a container and attached to the underside of the spacecraft – see image above. Here’s the inscription on the container: “Interned herein are remains of American Clyde W. Tombaugh, discoverer of Pluto and the solar system’s ‘third zone’ Adelle and Muron’s boy, Patricia’s husband, Annette and Alden’s father, astronomer, teacher, punster, and friend: Clyde W. Tombaugh (1906-1997).”
2. Me and about 434,000 other people, too! The “Send Your Name to Pluto” CD-ROM with more than over four hundred thousand names of people who wanted to participate in this great journey of exploration. I’m pumped about being along for the ride, and I hope you are on board, too!
3. A CD-ROM with pictures of New Horizons project personnel.
4. A Florida state quarter, from the state where New Horizons was launched.
5. A Maryland state quarter, from the state where New Horizons was built.
6. A small piece cut from SpaceShip One is installed on New Horizons’ lower inside deck, with a two-sided inscription. Front: “To commemorate its historic role in the advancement of spaceflight, this piece of SpaceShip One is being flown on another historic spacecraft: New Horizons. New Horizons is Earth’s first mission to Pluto, the farthest known planet in our solar system.” Back: “SpaceShip One was Earth’s first privately funded manned spacecraft. SpaceShip One flew from the United States of America in 2004.” Piece from SpaceShip One. Credit: JHU/APL
7. A U.S. Flag.
8. Another version of a U.S. Flag.
9. The 1991 U.S. stamp proclaiming, “Pluto: Not Yet Explored” Pluto US postal stamp from 1991. Credit: JHU/APL
New Horizons’ principal investigator Dr. Alan Stern disclosed the list of items at a ceremony at Smithsonian National Air and Space Museum’s Udvar-Hazy Center, where a model of the New Horizons spacecraft was added to the museum. Back in 2008, Stern petitioned the U.S. Postal Service to issue a new stamp for Pluto after the spacecraft arrived at Pluto, maybe something like this: Proposed new stamp for New Horizons. Credit: JHU/APL
Source: New Horizons website
We originally wrote this in 2008, but we thought you’d get a kick out of it since New Horizons is so close. We made a couple of updates to the text.
An artist's concept of a trans-Neptunian object(TNOs). The distant sun is reduced to a bright star at a distance of over 3 billion miles. The Dark Energy Survey (DES) has now released discovery of more TNOs. (Illustration Credit: NASA)
Sometimes when you stare at something long enough, you begin to see things. This is not the case with optical sensors and telescopes. Sure, there is noise from electronics, but it’s random and traceable. Stargazing with a telescope and camera is ideal for staring at the same patches of real estate for very long and repeated periods. This is the method used by the Dark Energy Survey (DES), and with less than one percent of the target area surveyed, astronomers are already discovering previously unknown objects in the outer Solar System.
The Dark Energy Survey is a five year collaborative effort that is observing Supernovae to better understand the structures and expansion of the universe. But in the meantime, transient objects much nearer to home are passing through the fields of view. Trans-Neptunian Objects (TNOs), small icy worlds beyond the planet Neptune, are being discovered. A new scientific paper, released as part of this year’s American Astronomical Society gathering in Seattle, Washington, discusses these newly discovered TNOs. The lead authors are two undergraduate students from Carleton College of Northfield, Minnesota, participating in a University of Michigan program.
The Palomar Sky Survey (POSS-1, POSS-2), the Sloan Digital Sky Survey, and every other sky survey have mapped not just the static, nearly unchanging night sky, but also transient events such as passing asteroids, comets, or novae events. The Dark Energy Survey is looking at the night sky for structures and expansion of the Universe. As part of the five year survey, DES is observing ten select 3 square degree fields for Type 1a supernovae on a weekly basis. As the survey proceeds, they are getting more than anticipated. The survey is revealing more trans-Neptunian objects. Once again, deep sky surveys are revealing more about our local environment – objects in the farther reaches of our Solar System.
DES is an optical imaging survey in search of Supernovae that can be used as weather vanes to measure the expansion of the universe. This expansion is dependent on the interaction of matter and the more elusive exotic materials of our Universe – Dark Energy and Dark Matter. The five year survey is necessary to achieve a level of temporal detail and a sufficient number of supernovae events from which to draw conclusions.
In the mean time, the young researchers of Carleton College – Ross Jennings and Zhilu Zhang – are discovering the transients inside our Solar System. Led by Professor David Gerdes of the University of Michigan, the researchers started with a list of nearly 100,000 observations of individual transients. Differencing software and trajectory analysis helped identify those objects that were trans-Neptunian rather than asteroids of the inner Solar System.
While asteroids residing in the inner solar system will pass quickly through such small fields, trans-Neptunian objects (TNOs) orbit the Sun much more slowly. For example, Pluto, at an approximate distance of 40 A.U. from the Sun, along with the object Eris, presently the largest of the TNOs, has an apparent motion of about 27 arc seconds per day – although for a half year, the Earth’s orbital motion slows and retrogrades Pluto’s apparent motion. The 27 arc seconds is approximately 1/60th the width of a full Moon. So, from one night to the next, TNOs can travel as much as 100 pixels across the field of view of the DES survey detectors since each pixel has a width of 0.27 arc seconds.
Composite Dark Energy Camera image of one of the sky regions that the collaboration will use to study supernovae, exploding stars that will help uncover the nature of dark energy. The outlines of each of the 62 charge-coupled devices can be seen. This picture spans 2 degrees across on the sky and contains 520 megapixels. (Credit: Fermilab)
The scientific sensor array, DECam, is located at Cerro Tololo Inter-American Observatory (CTIO) in Chile utilizing the 4-meter (13 feet) diameter Victor M. Blanco Telescope. It is an array of 62 2048×4096 pixel back-illuminated CCDs totaling 520 megapixels, and altogether the camera weighs 20 tons.
A simple plot of the orbit of one of sixteen TNOs discovered by DES observations. (Credit: Dark Energy Detectives)
With a little over 2 years of observations, the young astronomers stated, “Our analysis revealed sixteen previously unknown outer solar system objects, including one Neptune Trojan, several objects in mean motion resonances with Neptune, and a distant scattered disk object whose 1200-year orbital period is among the 50 longest known.”
Object 2013 TV158 is one of the objects discovered by the Carleton College and University of Michigan team. Observed more than a dozen times over 10 months, the animated gif shows two image frames from August 2014 taken two hours apart. 2013 TV158 takes 1200 years to orbit the Sun and is likely a few hundred kilometers across – about the size of the Grand Canyon. (Credit: Dark Energy Detectives)
“So far we’ve examined less than one percent of the area that DES will eventually cover,” says Dr. Gerdes. “No other survey has searched for TNOs with this combination of area and depth. We could discover something really unusual.”
Illustration of color distribution of the trans-Neptunian objects. The horizontal axis represents the difference in intensity between visual (green & yellow) and blue of the object, while the vertical axis is the difference between visual and red. The distribution indicates how TNOs share a common origin and physical makeup, as well as common weathering in space. Yellow objects serve as reference: Neptune’s moon Triton, Saturn’s moon Phoebe, centaur Pholus, and the planet Mars. The object’s color represents the hue of the object. The size of the objects are relative – the larger objects are more accurate estimates, while smaller objects are simply based on absolute magnitude. (Credit: Wikimedia, Eurocommuter)
What does it all mean? It is further confirmation that the outer Solar System is chock-full of rocky-icy small bodies. There are other examples of recent discoveries, such as the search for a TNO for the New Horizons mission. As New Horizons has been approaching Pluto, the team turned to the Hubble space telescope to find a TNO to flyby after the dwarf planet. Hubble made short shrift of the work, finding three that the probe could reach. However, the demand for Hubble time does not allow long term searches for TNOs. A survey such as DES will serve to uncover many thousands of more objects in the outer Solar System. As Dr. Michael Brown of Caltech has stated, there is a fair likelihood that a Mars or Earth-sized object will be discovered beyond Neptune in the Oort Cloud.
A new Avengers movie. A reboot of the Star Wars franchise. The final installment of the Hunger Games. The Martian makes it to the big screen. Yup, even if the zombie apocalypse occurs in 2015, it’ll still be a great year. But trading science fiction for fact, we’re also on track for a spectacular year in space science and exploration as well.
Humanity will get its first good look at Ceres and Pluto, giving us science writers some new pics to use instead of the same half dozen blurry dots and artist’s conceptions. SpaceX will also attempt a daring landing on a sea platform, and long duration missions aboard the International Space Station will get underway. And key technology headed to space and on Earth may lead the way to opening up the window of gravitational wave astronomy on the universe. Here’s 10 sure-fire bets to watch for in the coming year from Universe Today:
LISA Pathfinder deployed at L1. Credit: ESA/Artist’s concept.
10. LISA Pathfinder
A precursor to a full-fledged gravitational wave detector in space, LISA Pathfinder will be launching atop a Vega rocket from Kourou, French Guiana in July 2015. LISA stands for the Laser Interferometer Space Antenna, and the Pathfinder mission will journey to the L1 Lagrange point between the Earth and the Sun to test key technologies. LISA Pathfinder will pave the way for the full fledged LISA space platform, a series of three free flying spacecraft proposed for launch in the 2030s.
Looking down one of the arms of LIGO Hanford. Credit: Photo by author.
9. AdLIGO Goes Online
And speaking of gravitational waves, we may finally get the first direct detection of the same in 2015, when Advanced LIGO is set to go online. Comprised of two L-shaped detectors, one based in Livingston Louisiana, and another in Hanford Washington, AdLIGO will feature ten times the sensitivity of the original LIGO observatory. In fact, as was the case of the hunt for the Higgs-Boson by CERN, a non-detection of gravitational waves by AdLIGO would be a much stranger result!
A replica of the Hubble Space Telescope on display at the Kennedy Space Center. Credit: Photo by author.
8. Hubble Turns 25
Launched on April 24th, 1990 aboard the Space Shuttle Discovery, the Hubble Space Telescope celebrates 25 years in space in 2015. The final servicing mission in 2009 gave Hubble a reprieve from the space junk scrap heap, and the orbiting telescope is still going strong. Hubble has no less than pushed the limits in modern astronomy to become a modern icon of the space age.
MESSENGER wraps up its mission in 2015. Credit: NASA/MESSENGER/JPL/APL.
7. The End of MESSENGER
NASA’s Mercury exploring spacecraft wraps up its mission next year. Launched in 2004, MESSENGER arrived in orbit around Mercury after a series of flybys on March 18th, 2011. MESSENGER has mapped the innermost world in detail, and studied the space environment and geology of Mercury. In late March 2015, MESSENGER will achieve one final first, when it impacts the surface of Mercury at the end of its extended mission.
Akatsuki on Earth prior to departure. Credit: JAXA.
6. Akatsuki at Venus
This Japanese spacecraft missed orbital insertion a few years back, but gets a second chance at life in 2015. Launched in 2010 atop an H-IIA rocket from the Tanegashima Space Center in Japan, Akatsuki failed to enter orbit around Venus at the end of 2010, and instead headed out for a heliocentric path around the Sun. Some quick thinking by JAXA engineers led to a plan to attempt to place Akatsuki in Venusian orbit in November 2015. This would be a first for the Japanese space agency, as attempts by JAXA at placing a spacecraft in orbit around another planet – including the Mars Nozomi probe – have thus far failed.
The target for the Falcon-9 first stage later next week. Credit: SpaceX.
5. SpaceX to Attempt to Land on a Sea Platform
It’ll definitely rock if they pull it off next week: on January 6th, a SpaceX Falcon 9 rocket will lift off from Cape Canaveral with its Dragon spacecraft headed to the International Space Station on mission CRS-5. Sure, these resupply missions are becoming routine, but after liftoff, SpaceX is attempting something new and daring: landing the Falcon-9 first stage Buck Rodgers style, “fins first” on a floating barge. This is the next step in ultimately proving the feasibility of having the rocket fly back to the launch site for eventual reuse. If nothing else, expect some stunning video of the attempt soon!
An artist’s concept of an asteroid retrieval mission. Credit: NASA.
4. NASA to Decide on an Asteroid Mission
Some major decisions as to the fate and the future of manned space exploration are due next year, as NASA is expected to decide on the course of action for its Asteroid Redirect Mission. The current timeline calls for the test of the SLS rocket in 2018, and the launch of a spacecraft to recover an asteroid and place it in orbit around the Moon in 2019. If all goes according to plan – a plan which could always shift with the political winds and future changes in administrations – we could see astronauts exploring a captured asteroid by the early 2020s.
Astronaut Scott Kelly (left), and cosmonaut Mikhail Korniyenko. Credit: NASA/Roscomos.
3. Long Duration ISS Missions
Beginning in 2015, astronauts and cosmonauts will begin year-long stays aboard the ISS to study the effects of long duration space missions. In March of 2015, cosmonaut Mikhail Korniyenko and U.S. astronaut Scott Kelly will launch as part of Expedition 43 headed to the ISS. The Russians have conducted stays in space longer than a year aboard the Mir space station, but Kelly’s stay aboard the ISS will set a duration record for NASA astronauts. Perhaps, a simulated “Mars mission” aboard the ISS could be possible in the coming years?
An artist’s concept of Dawn approaching 1 Ceres. Credit: NASA/JPL.
2. Dawn at Ceres
Fresh off of exploring Vesta, NASA’s Dawn spacecraft will become the first mission to enter orbit around a second object, the asteroid 1 Ceres next year in April 2015. The largest asteroid and the first object of its kind discovered on the first day of the 19th century, Ceres looks to be a fascinating world in its own right. Does it possess water ice? Active geology? Moons of its own? If Dawn’s performance at Vesta was any indication, we’re in for another exhilarating round of space exploration!
And artist’s conception of New Horizons at Pluto. Credit: NASA/JPL/Thierry Lombry.
1. New Horizons at Pluto
An easy No. 1,we finally get our first good look at Pluto in July, as NASA’s New Horizons spacecraft flies less than 14,000 kilometres from the surface of the distant world. Launched in 2006, New Horizons will “thread the needle” between Pluto and Charon in a flurry of activity as it passes by. New Horizons will then turn back as it passes into the shadows of Pluto and Charon and actually view the two worlds as they occult the distant Sun. And from there, New Horizons will head out to explore Kuiper Belt Objects of opportunity.
And these are just the top stories that are slated to be big news in space in 2015. Remember, another Chelyabinsk meteor or the next big comet could drop by at any time… space news can be unpredictable, and its doubtless that 2015 will have lots more surprises in store.
A raw shot from the front hazcam of NASA's Opportunity rover taken on Sol 3757, on Aug. 19, 2014. Credit: NASA/JPL-Caltech
Feel like visiting a dwarf planet today? How about a comet or the planet Mars? Luckily for us, there are sentinels across the Solar System bringing us incredible images, allowing us to browse the photos and follow in the footsteps of these machines. And yes, there are even a few lucky humans taking pictures above Earth as well.
Below — not necessarily in any order — are some of the best space photos of 2014. You’ll catch glimpses of Pluto and Ceres (big destinations of 2015) and of course Comet 67P/Churyumov–Gerasimenko (for a mission that began close-up operations in 2014 and will continue next year.) Enjoy!
The Philae that could! The lander photographed during its descent by Rosetta. Credit: ESA/Rosetta/MPS for Rosetta Team/The Aurora Borealis seen from the International Space Station on June 28, 2014, taken by astronaut Reid Wiseman. Credit: Reid Wiseman/NASA.NASA’s Mars Curiosity Rover captures a selfie to mark a full Martian year — 687 Earth days — spent exploring the Red Planet. Curiosity Self-Portrait was taken at the ‘Windjana’ Drilling Site in April and May 2014 using the Mars Hand Lens Imager (MAHLI) camera at the end of the roboic arm. Credit: NASA/JPL-Caltech/MSSSThis global map of Dione, a moon of Saturn, shows dark red in the trailing hemisphere, which is due to radiation and charged particles from Saturn’s intense magnetic environment. Credit: NASA/JPL/Space Science InstituteComet Siding Spring shines in ultraviolet in this image obtained by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft. Credit: Laboratory for Atmospheric and Space Physics/University of Colorado; NASAThis “movie” of Pluto and its largest moon, Charon b yNASA’s New Horizons spacecraft taken in July 2014 clearly shows that the barycenter -center of mass of the two bodies – resides outside (between) both bodies. The 12 images that make up the movie were taken by the spacecraft’s best telescopic camera – the Long Range Reconnaissance Imager (LORRI) – at distances ranging from about 267 million to 262 million miles (429 million to 422 million kilometers). Charon is orbiting approximately 11,200 miles (about 18,000 kilometers) above Pluto’s surface. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)The Mars Reconnaissance Orbiter took this image of a “circular feature” estimated to be 1.2 miles (2 kilometers) in diameter. Picture released in December 2014. Credit: NASA/JPL-Caltech/University of ArizonaJets of gas and dust are seen escaping comet 67P/C-G on September 26 in this four-image mosaic. Click to enlarge. Credit: ESA/Rosetta/NAVCAMCeres as seen from the Earth-based Hubble Space Telescope in 2004 (left) and with the Dawn spacecraft in 2014 as it approached the dwarf planet. Hubble Credit: NASA, ESA, J. Parker (Southwest Research Institute), P. Thomas (Cornell University), L. McFadden (University of Maryland, College Park), and M. Mutchler and Z. Levay (STScI). Dawn Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA. Photo Combination: Elizabeth Howell
Two spacecraft, Dawn and New Horizon will reach their final objectives in 2015 - Dwarf Planets - Ceres and Pluto. (Credit: NASA, Illustration - T.Reyes)
Together, the space probes Dawn and New Horizons have been in flight for a collective 17 years. One remained close to home and the other departed to parts of the Solar System of which little is known. They now share a common destination in the same year: dwarf planets.
At the time of these NASA probes’ departures, Ceres had just lost its designation as the largest asteroid in our Solar System. Pluto was the ninth planet. Both probes now stand to deliver measures of new data and insight that could spearhead yet another revision of the definition of planet.
A comparison of the trajectories of New Horizons (left) and the Dawn missions (right). (Credit: NASA/JPL, SWRI, Composite- T.Reyes)
Certainly, NASA’s Year of the Dwarf Planet is an unofficial designation and NASA representatives would be quick to emphasize another dozen or more missions that are of importance during the year 2015. However, these two missions could determine the fate of billions or more small bodies just within our galaxy, the Milky Way.
If Ceres and Pluto are studied up close – mission success is never a sure thing – then what is observed could lead to a new, more certain and accepted definition of planet, dwarf planet, and possibly other new definitions.
The New Horizons mission became the first mission of NASA’s New Frontiers program, beginning development in 2001. The probe was launched on January 19, 2006, atop an Atlas V 551 (5 solid rocket boosters plus a third stage). Utilizing more compact and lightweight electronics than its predecessors to the outer planets – Pioneer 10 & 11, and Voyager 1 & 2 – the combination of reduced weight, a powerful launch vehicle, plus a gravity assist from Jupiter has lead to a nine year journey. On December 6, 2014, New Horizons was taken out of hibernation for the last time and now remains powered on until the Pluto encounter.
This “movie” of Pluto and its largest moon, Charon, by NASA’s New Horizons spacecraft taken in July 2014 clearly shows that the barycenter – the center of mass of the two bodies – resides outside (between) both bodies. The 12 images that make up the movie were taken by the spacecraft’s best telescopic camera – the Long Range Reconnaissance Imager (LORRI) – at distances ranging from about 267 million to 262 million miles (429 million to 422 million kilometers). Charon is orbiting approximately 11,200 miles (about 18,000 kilometers) above Pluto’s surface. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)
The arrival date of New Horizon is July 14, 2015. A telescope called the Long Range Reconnaissance Imager (LORRI) has permitted the commencement of observations while still over 240 million kilometers (150 million miles) from Pluto. The first stellar-like images were taken while still in the Asteroid belt in 2006.
Pluto was once the ninth planet of the Solar System. From its discovery in 1930 by Clyde Tombaugh until 2006, it maintained this status. In that latter year, the International Astronomical Union undertook a debate and then a membership vote that redefined what a planet is. The change occurred 8 months after New Horizons’ launch. There were some upset mission scientists, foremost of which was the principal investigator, Dr. Alan Stern, from the Southwest Research Institute in San Antonio, Texas. In a sense, the rug had been pulled from under them.
A gentleman’s battle ensued between opposing protagonists Dr. Stern and Dr. Michael Brown from Caltech. In 2001, Dr. Brown’s research team began to discover Kuiper belt objects (Trans-Neptunian objects) that rivaled the size of Pluto. Pluto suddenly appeared to be one of many small bodies that could likely number in the trillions within just one galaxy – ours. According to Dr. Brown, there could be as many as 200 objects in our Solar System similar to Pluto that, under the old definition, could be defined as planets. Dr. Brown’s work was the straw that broke the camel’s back – that is, it led to the redefinition of planet, and the native of Huntsville, Alabama, went on to write a popular book, How I Killed Pluto and Why It Had It Coming.
Dr. Stern’s story involving Pluto and planetary research is a longer and more circuitous one. Stern was the Executive Director of the Southwest Research Institute’s Space Science and Engineering Division and then accepted the position of Associate Administrator of NASA’s Science Mission Directorate in 2007. Clearly, after a nine year journey, Stern is now fully committed to New Horizons’ close encounter. More descriptions of the two protagonists of the Pluto debate will be included in a follow on story.
Artist’s concept depicting the Dawn spacecraft thrusting with its ion propulsion system as it travels from Vesta (lower right) to Ceres (upper left). The galaxies in the background are part of the Virgo supercluster. Dawn, Vesta, and Ceres are currently in the constellation Virgo from the perspective of viewers on Earth. (Image credit: NASA/JPL)
The JPL and Orbital Science Corporation developed Dawn space probe began its journey to the main asteroid belt on September 27, 2007. It has used gravity assists and flew by the planet Mars. Dawn spent 14 months surveying Vesta, the 4th largest asteroid of the main belt (assuming Ceres is still considered the largest). While New Horizons has traveled over 30 Astronomical Units (A.U.) – 30 times the distance from the Earth to the Sun – Dawn has remained closer and required reaching a little over 2 A.U. to reach Vesta and now 3 A.U. to reach Ceres.
The Dawn mission had the clear objective of rendezvous and achieving orbit with two asteroids in the main belt between Mars and Jupiter. Dawn was also sent packing the next generation of Ion Propulsion. It has proven its effectiveness very well, having used ion propulsion for the first time to achieve an orbit. Pretty simple, right? Not so fast.
As Dawn was passing critical design reviews during development, the redefinition of planet lofted its second objective – the asteroid 1 Ceres – to a new status. While Pluto was demoted, Ceres was promoted from its scrappy status of biggest of the asteroids – the debris, the leftovers of our solar system’s development – to dwarf planet. Even 4 Vesta is now designated a proto-planet.
Artist rendition of Dawn spacecraft orbiting Vesta. (Credit: NASA/JPL-Caltech)
So now the stage is set. Dawn will arrive first at a dwarf planet – Ceres – in April. With a small, low gravity body and ion propulsion, the arrival is slow and cautious. If the two missions fair well and achieve their goals, 2015 is likely to become a pivotal year in the debate over the classification of non-stellar objects throughout the universe.
Just days ago, at the American Geophysical Union Conference in San Francisco, Dr. Stern and team described the status and more details of the goals of New Horizons. Since arriving, more moons of Pluto have been discovered. There is the potential that faint rings exist and Pluto may even harbor an interior ocean due to the tidal forces from its largest moon, Charon. And Dawn mission scientists have seen the prospects for Ceres’ change. Not just the status, the latest Hubble images of Ceres is showing bright spots which could be water ice deposits and could also harbor an internal ocean.
The Solar System is becoming a more crowded place. This picture shows the sizes of dwarf planets Pluto, Ceres, Eris, and Makemake as compared to Earth and Earth’s Moon, here called “Luna.” None of the distances between objects are to scale. (Credit: NASA)
So other NASA missions notwithstanding, this is the year of the dwarf planet. NASA will provide Humanity with its first close encounters with the most numerous of small round – by their self-gravity – bodies in the Universe. They are now called dwarf planets but ask Dr. Stern and company, the public, and many other planetary scientists and you will discover that the jury is still out.
