Space and astronomy news
Pluto was discovered in 1930 by astronomer Clyde Tombaugh. For decades, not much detail was known about the erstwhile planet. We assumed it was a frozen, dormant world.
Continue reading “New Horizons Team Pieces Together the Best Images They Have of Pluto’s Far Side”
Spectacular imagery of huge regions of flowing ice, monumental mountain ranges and a breathtakingly backlit atmospheric haze showing Pluto as we’ve never seen it before, were among the newest discoveries announced today, July 24, by scientists leading NASA’s New Horizons mission which sped past the planet for humanity’s first ever up-close encounter only last week.
New Horizon’s revealed Pluto be an unexpectedly vibrant “icy world of wonders” as it barreled by the Pluto-Charon double planet system last Tuesday, July 14, at over 31,000 mph (49,600 kph).
The scientists publicly released a series of stunning new images and science discoveries at Pluto that exceeded all pre-flyby expectations.
“The images of Pluto are spectacular,” said John Grunsfeld, NASA’s associate administrator for the Science Mission Directorate, at today’s media briefing.
“We knew that a mission to Pluto would bring some surprises, and now — 10 days after closest approach — we can say that our expectation has been more than surpassed. With flowing ices, exotic surface chemistry, mountain ranges, and vast haze, Pluto is showing a diversity of planetary geology that is truly thrilling.”
Over 50 gigabits of data were collected during the encounter and flyby periods of the highest scientific activity in the most critical hours before and after the spacecrafts closest approach to Pluto, its largest moon Charon and its quartet of smaller moons.
Data from the flyby is now raining back to Earth, but slowly due to limited bandwidth of an average “downlink” of only about 2 kilobits per second via its two transmitters.
“So far we’ve seen only about 5% of the encounter data,” said Jim Green, director of Planetary Science at NASA Headquarters in Washington.
At that pace it will take about 16 months to send all the flyby science data back to Earth.
Among the top highlights is the first view ever taken from the back side of Pluto, a backlit view that humans have never seen before.
It shows a global portrait of the planets extended atmosphere and was captured when NASA’s New Horizons spacecraft was about 1.25 million miles (2 million kilometers) from Pluto. It shows structures as small as 12 miles across.
“The silhouette of Pluto taken after the flyby and show a remarkable haze of light representing the hazy worlds extended atmosphere,” Alan Stern, principal investigator for New Horizons at the Southwest Research Institute (SwRI) in Boulder, Colorado, said at the media briefing.
“The image is the equivalent of the Apollo astronauts Earth-rise images.”
“It’s the first image of Pluto’s atmosphere!” said Michael Summers, New Horizons co-investigator at George Mason University in Fairfax, Virginia, at the briefing.
“We’ve known about the atmosphere for over 25 years,” and now we can see it. There are haze layers and it shows structure and weather. There are two distinct layers of haze. One at about 30 miles (50 kilometers) and another at about 50 miles (80 kilometers) above the surface.”
“The haze extend out about 100 miles! Which is five times more than expected.”
The image was taken by New Horizons’ high resolution Long Range Reconnaissance Imager (LORRI) while looking back at Pluto, barely seven hours after closest approach at 7:49 a.m. EDT on July 14, and gives significant clues about the atmosphere’s dynamics and interaction with the surface. It captures sunlight streaming through the atmosphere.
“The hazes detected in this image are a key element in creating the complex hydrocarbon compounds that give Pluto’s surface its reddish hue.”
Methane (CH4) in the upper atmosphere break down by interaction of UV radiation and forms ethylene and acetylene which leads to more complex hydrocarbons known as tholins – which the team says is responsible for Pluto’s remarkable reddish hue.
The team also released new LORRI images showing “extensive evidence of exotic ices flowing across Pluto’s surface and revealing signs of recent geologic activity, something scientists hoped to find but didn’t expect.”
The images focuses on Sputnik Planum, a Texas-sized plain, which lies on the western, left half of Pluto’s bilobed and bright heart-shaped feature, known as Tombaugh Regio.
New imagery and spectral evidence from the Ralph instrument was presented that appears to show the flow of nitrogen ices in geologically recent times across a vast region. They appear to flow similar to glaciers on Earth. There are also carbon monoxide and methane ices mixed in with the water ices.
“We’ve only seen surfaces like this on active worlds like Earth and Mars,” said mission co-investigator John Spencer of SwRI. “I’m really smiling.”
“At Pluto’s temperatures of minus-390 degrees Fahrenheit, these ices can flow like a glacier,” said Bill McKinnon, deputy leader of the New Horizons Geology, Geophysics and Imaging team at Washington University in St. Louis.
“In the southernmost region of the heart, adjacent to the dark equatorial region, it appears that ancient, heavily-cratered terrain has been invaded by much newer icy deposits.”
“We see the flow of viscous ice that looks like glacial flow.”
If the spacecraft remains healthy as expected, the science team plans to target New Horizons to fly by another smaller Kuiper Belt Object (KBO) as soon as 2018.
Watch for Ken’s continuing coverage of the Pluto flyby. He was onsite reporting live on the flyby and media briefings for Universe Today from the Johns Hopkins University Applied Physics Laboratory (APL), in Laurel, Md.
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
This annotated view of a portion of Pluto’s Sputnik Planum (Sputnik Plain), named for Earth’s first artificial satellite, shows an array of enigmatic features. The surface appears to be divided into irregularly shaped segments that are ringed by narrow troughs, some of which contain darker materials. Features that appear to be groups of mounds and fields of small pits are also visible. This image was acquired by the Long Range Reconnaissance Imager (LORRI) on July 14 from a distance of 48,000 miles (77,000 kilometers). Features as small as a half-mile (1 kilometer) across are visible. Credits: NASA/JHUAPL/SWRI
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A vast, hundreds of miles wide craterless plain of Plutonian ice no more than 100 million years old and centered amidst Pluto’s big ‘heart’ was unveiled in spectacular new imagery taken by NASA’s resounding successful New Horizons mission, during its history making rapid transit through the Pluto-Charon binary planet system barely three days ago, on Tuesday, July 14.
The jaw dropping new imagery of young plains of water ice was publicly released today, July 17, by NASA and scientists leading the New Horizons mission during a media briefing, and has already resulted in ground breaking new scientific discoveries at the last planet in our solar system to be visited by a spacecraft from Earth.
“We have now visited every planet in our solar system with American spacecraft,” said NASA Administrator Charles Bolden. “These findings are already causing us to rethink the dynamics of interior geologic processes.”
New data and dazzling imagery are now from streaming back some 3 billion miles across interplanetary space to mission control on Earth and researchers eagerly awaiting the fruits of more than two decades of hard labor to get to this once-in-a-lifetime opportunity.
“I can’t wait for the new discoveries!” exclaimed Bolden at today’s media briefing.
“Over 50 gigabits of data were collected during the encounter and flyby periods,” New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado, said during the media briefing.
“So far less than 1 gigabit of data has been returned.”
It will take some 16 months for all the Pluto flyby data to be transmitted back to Earth.
And the team has not been disappointed because the results so far shows Pluto to possess tremendously varied terrain that “far exceed our expectations.”
Video Caption: In the center left of Pluto’s vast heart-shaped feature – informally named “Tombaugh Regio” – lies a vast, craterless plain that appears to be no more than 100 million years old, and is possibly still being shaped by geologic processes. This frozen region is north of Pluto’s icy mountains and has been informally named Sputnik Planum (Sputnik Plain), after Earth’s first artificial satellite. Credits: NASA/JHUAPL/SWRI
Two new high resolution images captured by the probes Long Range Reconnaissance Imager (LORRI) on July 14 were released today and taken from a distance of 48,000 miles (77,000 kilometers). Features as small as one-half mile (1 kilometer) across are visible in the images – shown above and below.
They were snapped from frozen region lying north of Pluto’s icy mountains, in the center-left of the heart feature, informally named “Tombaugh Regio” (Tombaugh Region) after Clyde Tombaugh, who discovered Pluto in 1930.
“This terrain is not easy to explain,” said Jeff Moore, leader of the New Horizons Geology, Geophysics and Imaging Team (GGI) at NASA’s Ames Research Center in Moffett Field, California.
“The discovery of vast, craterless, very young plains on Pluto exceeds all pre-flyby expectations.”
“The landscape is astounding. There are a few ancient impact craters on Pluto. But other areas like “Tombaugh Regio” show no craters. The landform change processes are occurring into current geologic times.”
“There are no impact craters in a frozen area north of Pluto’s icy mountains we are now informally calling ‘Sputnik Planum’ after Earth’s first artificial satellite.”
‘Sputnik Planum’ is composed of a broken surface of irregularly-shaped segments. The polygonal shaped areas are roughly 12 miles (20 kilometers) across, bordered by what appear to be shallow troughs based on a quick look at the data.
Notably, some of the clumps are filled with mysterious darker material. Hills are also visible in some areas, which may have been pushed up. Etched areas on the surface may have been formed by sublimation process where the water ice turns directly from the solid to the gas phase due to the extremely negligible atmosphere pressure.
In some places there are also streaks that may have formed from windblown processes and pitted areas.
“It’s just pure coincidence that we got the highest resolution data at Sputnik Planum which is of the most interest scientifically,” Moore noted.
Moore indicated that the team is working on a pair of theories as to how these polygonal segments were formed.
“The irregular shapes may be the result of the contraction of surface materials, similar to what happens when mud dries. Alternatively, they may be a product of convection, similar to wax rising in a lava lamp. On Pluto, convection would occur within a surface layer of frozen carbon monoxide, methane and nitrogen, driven by the scant warmth of Pluto’s interior,” Moore explained.
Pluto’s polygons look remarkably similar to the Martian polygons upon which NASA’s Phoenix lander touched down on in 2008 and dug into. Perhaps they were formed by similar mechanisms or difference ones, contraction or convection, Moore told me during the briefing.
As of yesterday, New Horizons spacecraft completed and exited the Pluto encounter phase, said Stern. “We are now collecting departure science.”
New Horizons is already over 3 million miles beyond Pluto and heading to its next yet to be determined target in the Kuiper Belt.
“With the flyby in the rearview mirror, a decade-long journey to Pluto is over –but, the science payoff is only beginning,” said Jim Green, director of Planetary Science at NASA Headquarters in Washington.
“Data from New Horizons will continue to fuel discovery for years to come.”
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
The New Horizons mission team celebrates successful flyby of Pluto in the moments after closest approach at 7:49 a.m. EDT on July 14, 2015. New Horizons Principal Investigator Alan Stern of Southwest Research Institute (SwRI), Boulder, CO., left, Johns Hopkins University Applied Physics Laboratory (APL) Director Ralph Semmel, center, and New Horizons Co-Investigator Will Grundy Lowell Observatory hold an enlarged print of an U.S. stamp with their suggested update after Pluto became the final planet in our solar system to be explored by an American space probe (crossing out the words ‘not yet’) – at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. Credit: Ken Kremer/kenkremer.com
New Horizons’ last look at Pluto’s Charon-facing hemisphere reveals the highest resolution view of four intriguing darks spots for decades to come. This image, taken early the morning of July 11, 2015, shows newly-resolved linear features above the equatorial region that intersect, suggestive of polygonal shapes. This image was captured when the spacecraft was 2.5 million miles (4 million kilometers) from Pluto. Credit: NASA/JHUAPL/SWRI
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Today (July 11) we got our last, best and clearest look at a quartet of perplexing dark spots on Pluto’s far side from NASA’s New Horizons spacecraft – now just two days and two million miles (4 million km) out from history’s first ever up close flyby of the Pluto system on Tuesday, July 14.
The four puzzling spots (see above) are located on the hemisphere of Pluto which always faces its largest moon, Charon, and have captivated the scientists and public alike. Pluto and Charon are gravitationally locked with an orbital period of 6.4 days.
Over only the past few days, we are finally witnessing an amazing assortment of geological wonders emerge into focus from these never before seen worlds – as promised by the New Horizons team over a decade ago.
Be sure to take a good hard look at the image, because these spots and Pluto’s Charon-facing hemisphere will not be visible to New Horizons cameras and spectrometers during the historic July 14 encounter as the spacecraft whizzes by the binary worlds at speeds of some 30,800 miles per hour (more than 48,600 kilometers per hour) for their first up close reconnaissance.
And it’s likely to be many decades before the next visitor from Earth arrives at the frigid worlds at the far flung reaches of our solar system for a longer look, hopefully from orbit.
“The [July 11] image is the last, best look that anyone will have of Pluto’s far side for decades to come,” said New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado, in a statement.
The image of the mysterious spots was taken earlier today (July 11) by New Horizons Long Range Reconnaissance Imager (LORRI) at a distance of 2.5 million miles (4 million kilometers) from Pluto, and just released by NASA. The image resolution is 10 miles per pixel. One week ago it was only 40 miles per pixel.
They were first seen only in very recent LORRI images as Pluto’s disk finally was resolved and are located in a Missouri sized area about 300 miles (480 kilometers) across and above the equatorial region.
But until today they were still rather fuzzy – see image below from July 3! What a difference a few million miles (km) makes!
“The Pluto system is totally unknown territory,” said Dr. John Spencer, New Horizons co-investigator at today’s (July 11) daily live briefing from NASA and the New Horizons team.
“Pluto is like nowhere we’ve even been before. It is unlike anything we’ve visited before.”
Now, with the $700 million NASA planetary probe millions of miles closer to the double planet, the picture resolution has increased dramatically and the team can at least speculate.
Researchers say the quartet of “equally spaced” dark splotches are “suggestive of polygonal shapes” and the “boundaries between the dark and bright terrains are irregular and sharply defined.”
“It’s weird that they’re spaced so regularly,” says New Horizons program scientist Curt Niebur at NASA Headquarters in Washington.
However their nature remains “intriguing” and truly “unknown.”
“We can’t tell whether they’re plateaus or plains, or whether they’re brightness variations on a completely smooth surface,” added Jeff Moore of NASA’s Ames Research Center, Mountain View, California.
“It’s amazing what we are seeing now in the images, showing us things we’ve never seen before,” said Spencer.
“Every day we see things we never knew before. We see these crazy black and white patterns. And we have no idea what these mean.”
Answering these questions and more is what the encounter is all about.
Pluto is just chock full of mysteries, with new ones emerging every day as New Horizons at last homes in on its quarry, and the planet grows from a spot to an enlarging disk with never before seen surface features, three billion miles from Earth after an interplanetary journey of some nine and a half years.
“We see circular things and wonder are those craters? Or are they something else,” Spencer elaborated.
“We saw circular features on Neptune’s moon Triton that are not craters. So we should know in a few days . But right now we are just having an awful lot of fun just speculating. It’s just amazing.”
Until a few days ago, we didn’t know that “the other Red Planet” had a big bright heart and a dark ‘whale-shaped’ feature – see my earlier articles; here and here.
“When we combine images like this of the far side with composition and color data the spacecraft has already acquired but not yet sent to Earth, we expect to be able to read the history of this face of Pluto,” Moore explained.
New Horizons will swoop to within about 12,500 kilometers (nearly 7,750 miles) of Pluto’s surface and about 17,900 miles (28,800 kilometers) from Charon during closest approach at approximately 7:49 a.m. EDT (11:49 UTC) on July 14.
The probe was launched back on Jan. 19, 2006 on a United Launch Alliance Atlas V rocket on a 9 year voyage of over 3.6 billion miles (5.7 billion km).
Pluto is the last of the nine classical planets to be explored up close and completes the initial the initial reconnaissance of the solar system nearly six decades after the dawn of the space age. It represents a whole new class of objects.
“Pluto is a member of a whole new family of objects,” said Jim Green, director of Planetary Science, NASA Headquarters, Washington, in today’s live Pluto update.
“We call that the Kuiper Belt. And it is the outer solar system.”
New Horizons is equipped with a suite of seven science instruments gathering data during the approach and encounter phases with the Pluto system.
The New Frontiers spacecraft was built by a team led by Stern and included researchers from SwRI and the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. APL also operates the New Horizons spacecraft and manages the mission.
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
Latest color image of Pluto taken on July 3, 2015 shows 4 mysterious dark spots.
Best yet image of Pluto was taken by the LORRI imager on NASA’s New Horizons spacecraft on July 3, 2015 at a distance of 7.8 million mi (12.5 million km), just prior to the July 4 anomaly that sent New Horizons into safe mode. Color data taken from the Ralph instrument gathered earlier in the mission. Credit: NASA/JHUAPL/SWRI
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Despite some hair-raising and unplanned 4th of July fireworks of sorts in deep space which caused NASA’s Pluto bound New Horizons spacecraft to enter “safe mode” due to a computer glitch and temporarily halt all science operations over the weekend, the spacecraft is now fully back on track, “healthy” and working “flawlessly” and set to resume all planned research investigations on Tuesday, July 7, NASA and top mission managers announced at a media briefing held this afternoon, Monday, July 6.
It’s now just exactly one week before the once-in-a-lifetime opportunity for a fast flyby encounter of the ever intriguing binary planet, at the far flung reaches of the solar system. And the great news could not come soon enough given the proximity of the flyby.
“The spacecraft is in excellent health and back in operation. New Horizons is barreling towards the Pluto system,” stated Jim Green, director of Planetary Science, NASA Headquarters, Washington, at the start of today’s news media briefing.
The $700 million mission remains on track to conduct the complex close flyby science sequence in its entirety, as planned over the next week, including the July 14 flyby of Pluto, despite the scary safe mode episode.
“The New Horizons spacecraft and science payload are now operating flawlessly,” Alan Stern, New Horizons principal investigator, Southwest Research Institute, Boulder, Colorado, announced at the media briefing.
NASA unexpectedly lost contact with the New Horizons spacecraft on Saturday, July 4, at about 1:30 p.m. EDT after it suffered a memory related software anomaly and executed a protective operation known as “safe mode.” An anomaly investigation team was formed immediately.
“It’s really a historic time, but also fraught with many decisions and challenges on the way to the July 14 Pluto system encounter,” Green said.
The mission team quickly worked to reestablish contact with the piano shaped spacecraft about 90 minutes after the signal was lost.
“On Saturday we lost contact with the spacecraft. The New Horizons team immediately went into action. Within 90 minutes the signal was reacquired by the team, with the spacecraft in safe mode. They soon found the root cause and corrective actions were immediately taken to get the spacecraft back in business.”
The team worked tirelessly and diligently day and night over the holiday weekend to recover New Horizons back to full operation quickly and in time for the flyby encounter of Pluto on July 14, set for approximately 7:49 a.m. EDT (11:49 UTC) on July 14, said Glen Fountain, New Horizons project manager, Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland.
There are no second chances.
The software glitch occurred a day after new operating software was uploaded to New Horizons last Friday.
The spacecraft was trying to do two things at once on Saturday, compressing science data and writing command sequences while using up too much flash memory, explained Fountain.
“The computer was trying to do these two things at the same time, and the two were more than the processor could handle,” Fountain said.
“So the processor said ‘I’m overloaded.’ Then the spacecraft did exactly what it was supposed to do. It then switched to the backup computer and went into safe mode. At that point, we lost the downlink from the primary computer. We realized quickly what happened and put a recovery plan in place and recovered.”
At this moment New Horizons is about 3 billion miles (4.9 billion km) from Earth and less than 6 million miles (9 million km) away from unmasking the secrets of tantalizing Pluto, Charon, its largest moon with which it forms a double planet system, and its four tiny and recently discovered moons. Charon is half the size of Pluto.
The round trip time for signals traveling at the speed of light is 8.5 hours. So it’s a very long time before commands from Earth can reach the spacecraft and for the team to determine their outcome. So the probe has to be able to operate on its own without direction from Earth during the intense and brief flyby period.
Pluto is the most distant and last unexplored planet in our Solar System, and therefore presents enormous complexities to those bold enough to dare the mightiest things.
“We expect a nominal flyby of Pluto from every indication now,” said Alan Stern, New Horizons principal investigator, Southwest Research Institute, Boulder, Colorado, announced at the media briefing.
“This object is unlike any other that we have observed,” Stern said. “Both Pluto and Charon are already surprising us.”
Less than 1 percent of the planned data was lost in the three days that the science instruments were shut off.
“It’s more important to focus on the later science during the flyby,” Stern elaborated.
“There is zero impact to the primary Group 1 highest-priority science objectives. And a minor impact to Group 2 and Group 3 objectives,” Stern elaborated.
“This is a speed bump in terms of the total return that we expect from this flyby.”
“I’m pleased that our mission team quickly identified the problem and assured the health of the spacecraft,” noted Green. “Now, with Pluto in our sights, we’re on the verge of returning to normal operations and going for the gold.”
The team said this type of software update will not be repeated and a similar type safe mode event should not recur.
Fountain said that during the encounter period, the probe can switch itself to exit safe mode event within about 7 minutes, depending on the situation, and minimize any science data losses.
New Horizons will swoop to within about 12,500 kilometers (nearly 7,800 miles) of Pluto’s surface.
It will zoom past Pluto at speeds of some 30,000 miles per hour (more than 48,000 kilometers per hour).
Today the team also released the best yet images of Pluto that were taken by the Long Range Reconnaissance Imager (LORRI). The trio of images were between July 1 and 3 of 2015, prior to the July 4 anomaly that sent New Horizons into safe mode.
The images show varying and enigmatic surface features on the different hemispheres of Pluto.
They also show the four mysterious dark spots on Pluto that have captured the imagination of the scientists and the world.
Their nature remains unknown at this time.
The probe was launched back in 2006 on a United Launch Alliance Atlas V rocket.
“We are on our way to Pluto!” Green exclaimed.
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
Less than a year from now, the New Horizons spacecraft will begin its encounter with Pluto. While closest approach is scheduled for July 2015, the Long Range Reconnaissance Imager or “LORRI” will begin snapping photos of the Pluto system six months earlier.
This first mission to Pluto has been a long time coming, and this new “trailer” put out by the New Horizons team recounts what it has taken to send the fastest spacecraft ever on a 5 billion km (3 billion mile) journey to Pluto, its largest moon, Charon, and the Kuiper Belt beyond. The spacecraft has been zooming towards the edge of our Solar System for over eight years since it launched on January 19, 2006.
By late April 2015, the approaching spacecraft will be taking pictures of Pluto that surpass the best images to date from Hubble. By closest approach in July 2015 –- when New Horizons will be 10,000 km from Pluto — a whole new world will open up to the spacecraft’s cameras. If New Horizons flew over Earth at the same altitude, it’s cameras could see individual buildings and their shapes.
“Humankind hasn’t had an experience like this–an encounter with a new planet–in a long time,” said Alan Stern, New Horizons’ principal investigator. “Everything we see on Pluto will be a revelation.”
It’s likely there could be some new planetary bodies discovered during the mission in addition to the five known moons: Charon, Styx, Nix, Kerberos, and Hydra.
“There is a real possibility that New Horizons will discover new moons and rings as well,” says Stern.
No matter what, Stern said, this is going to be an amazing ride.
“We’re flying into the unknown,” he said, “and there is no telling what we might find.”
See the countdown clock and find out more about the mission at the New Horizons website.
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With nearly two-thirds of its journey complete, the New Horizons spacecraft is still alive and well. It recently experienced a “hibernation wakeup” which started on November 5th and will last until November 15th… and it will sleep again until a month-long call in January. However, the real “wakeup call” may be when it reaches the complicated Pluto system. Watch out for that rock!
As more and more moons are discovered around Pluto, the higher the probability becomes of one of them – or debris surrounding them – could impact the delicate probe. With P4 discovered just a few short months ago, scientists are beginning to wonder just how many more are there which are too small and faint to be seen.
Says New Horizons Principal Investigator Alan Stern: “Even more worrisome than the possibility of many small moons themselves is the concern that these moons will generate debris rings, or even 3-D debris clouds around Pluto that could pose an impact hazard to New Horizons as it flies through the system at high speed. After all, at our 14-kilometer-per-second flyby speed, even particles less than a milligram can penetrate our micrometeoroid blankets and do a lot of damage to electronics, fuel lines and sensors.”
To enable research into what might be a prospective problem, the New Horizons team brought together about 20 of the world’s experts in ring systems, orbital dynamics and state-of-the-art astronomical observing techniques to search for small satellites and rings at distant Pluto. During a two day workshop, the group hashed and rehashed every possible scenario – including all the hazards that a small moon and debris-strewn system might cause.
“We found a plausible chance that New Horizons might face real danger of a killer impact; and that to mitigate that hazard, we need to undertake two broad classes of work.” said Stern. “First, we need to look harder at the Pluto system for still undiscovered satellites and rings. The best tools for this are going to be the Hubble Space Telescope, some very large ground-based telescopes, telescopes that can make stellar occultation observations of the space between Pluto and Charon where New Horizons is currently targeted, and thermal observations of the system by the ALMA radio telescope array just now being commissioned.”
The next step is planning – planning on a possible safer route through the Pluto system in the event that observations confirm navigational hazards. Studies presented at the Encounter Hazards Workshop show a good “safe haven bailout trajectory” (or SHBOT) could be designed to target a closest-approach aim point about 10,000 kilometers farther than the nominal mission trajectory. In this case, it would be a matter of aiming more towards Charon’s orbit, where the moon itself has cleared a path. However, even 180 degrees away on closest approach may not be enough. There’s always a chance of a debris field – one that doesn’t follow a plane, but has created a torus. In this event, material could be sailing along at speeds of up to 1-2 kilometers per second. Enough to annihilate delicate instruments.
“The question of whether the Pluto system could be hazardous to New Horizons remains open –but one we’ll be studying hard over the next year, with everything from computer models to big ground-based telescopes to the Hubble.” concludes Stern. “I’ll report on results as we obtain them, but it is not lost on us that there is a certain irony that the very object of our long-held scientific interest and affection may, after so many years of work to reach her, turn out to be less hospitable than other planets have been. We’ll see.”
Original Story Source: New Horizons News.