Tag Archives: Pluto

Mountains and craters on Pluto?

The edge of Tombaugh Regio

Cool image time! Even as they download new images for a press conference on Friday, the New Horizons’ science team has released a new close-up of Tombaugh Regio, showing both a new mountain range within it as well as its sharply defined western contact with the dark whale feature, which now appears to be heavily cratered and old.

“There is a pronounced difference in texture between the younger, frozen plains to the east and the dark, heavily-cratered terrain to the west,” said Jeff Moore, leader of the New Horizons Geology, Geophysics and Imaging Team (GGI) at NASA’s Ames Research Center in Moffett Field, California. “There’s a complex interaction going on between the bright and the dark materials that we’re still trying to understand.” While Sputnik Planum is believed to be relatively young in geological terms – perhaps less than 100 million years old — the darker region probably dates back billions of years. Moore notes that the bright, sediment-like material appears to be filling in old craters (for example, the bright circular feature to the lower left of center).

Make sure you click through to see the full resolution image. It is quite astonishing. They have also released a new image each of two of Pluto’s moons.


More Pluto news!

Sputnik Planum on Pluto

At a press conference today Alan Stern led off by dubbing Pluto-Charon as a “double planet system”. Some new results:

  • Tombaugh Regio (the heart) has been identified as a region of carbon monoxide.
  • The atmosphere extends out to about 600 miles. It is comprised of hydrocarbosn, methane, and nitrogen, with nitrogen the main component. It is naturally escaping from the planet, ionized by the solar wind. The consequence is that a substantial amount of Pluto has evaporated away over time. The numbers are not yet quantified, but will be as more data arrives.
  • The images once again suggest significant activity over time, both of erosion and tectonic processes. One flat plain, dubbed Sputnik Planum, is what one scientist described as “difficult to explain terrain.” The image is to the right. Some of its features resemble icecap glaciers, which are formed by processes that do not exist on Pluto. There also appear to be wind streaks on this planum!
  • They have named a mile high mountain has been dubbed Norgay Montes after the man who accompanied Edmund Hillary to the summit of Mt. Everest.

As the scientists warned today, every conclusion right now is very speculative, and should be taken with a very big grain of salt.


Weird geology on Charon

Charon's mountain in a moat

As they await the arrival of more data from New Horizons, the science team have highlighted this interesting and entirely puzzling feature revealed in their first global image from Charon, shown in the image on the right, a mountain inside a depression. Note also the nearby rill-like depressions running from one crater to the next.

My first thought is that the mountain, which in this relatively low resolution image looks almost like a really gigantic boulder, is made of material denser than the ground in which it sits, and some heating event caused the ground to soften and collapse, dropping the mountain-sized boulder down into the sinkhole.

I am guessing of course. What we have here is a very alien environment, with geological processes in temperatures and densities and gravities to which we are wholly unfamiliar. What we would normally expect to happen is not something we should expect to normally happen on either Charon or Pluto.


First New Horizons fly-by images released

Ice mountains on Pluto

Many cool images! I will only post one, on the right, of the ice mountains seen at the southernmost edge of Tombauh Regio. More can be seen here.

Some quick facts revealed during today’s the press conference:

  • They have gotten good data on Pluto’s atmosphere. Earlier data just before fly-by suggested that there are specific regions on the surface that have a lot of methane, but with different properties depending on location.
  • They have found that the surface of Charon is active. It also looks like a weird Moon, cratered, with a dark mare region they have dubbed Mordor. Its cause however is not the same as the Moon. There are also a large sequence of troughs and cliffs that are unlike other planets. Some areas are very smooth, as they they have been repaved after cratering. And there is a canyon that is very very deep, 3 miles deep, that makes it relatively deeper than any other canyon in the solar system.
  • Pluto’s moon Hydra is not spherical, and in fact looks like an asteroid.
  • The white heart is now been named Tombaugh Regio after one of Pluto’s discoverers. In its southern extent there are mountains and strange pits. And this area has no impact craters, meaning this is a very young surface, less than 100 million years old. The mountains have to made of ice, which is essentially the only thing that can be bedrock at Pluto’s temperatures, based on what they think Pluto is composed of.
  • The data shows repeatedly that a tiny planet can still have geological activity after billions of years, even without a giant gas giant nearby to produce tidal heating.
  • They have named the giant whale-shaped dark region at the equator Cthulu Regio.

The data and images will be coming back from New Horizons for the next year, so the show is certainly not over.


“We are in lock with telemetry with the spacecraft!”

The quote above was a confirmation from mission control that New Horizons survived the fly-by and is functioning perfectly.

They are still confirming if everything is A-Okay, but so far everything appears to exactly that. People are very jubilant at mission control.

They got the signal early, at the very beginning of their window.

They have now confirmed that they have a healthy spacecraft, and that “They are outbound from Pluto.”


Pluto and Charon in false color

Pluto and Charon in false color

While waiting for word about how New Horizons has fared during its close fly-by of Pluto, the science team today released the false color images on the right of both Pluto and Charon to illustrate the complicated surface geology of both planetary bodies.

The new color images reveal that the “heart” of Pluto actually consists of two remarkably different-colored regions. In the false-color image, the heart consists of a western lobe shaped like an ice cream cone that appears peach color in this image. A mottled area on the right (east) side looks bluish. A mid-latitude band appears in shades ranging from pale blue through red. Even within the northern polar cap, in the upper part of the image, various shades of yellow-orange indicate subtle compositional differences. This image was obtained using three of the color filters of the Ralph instrument on July 13 at 3:38 am EDT and received on the ground on at 12:25 pm.

The surface of Charon is viewed using the same exaggerated color. The red on the dark northern polar cap of Charon is attributed to hydrocarbon and other molecules, a class of chemical compounds called tholins. The mottled colors at lower latitudes point to the diversity of terrains on Charon. This image was obtained using three of the color filters of the Ralph instrument on July 13 at 3:38 am EDT and received on the ground on at 12:25 pm.

Word on the spacecraft’s status will arrive at around 9 pm (eastern) tonight. Images and data will then follow, assuming all is well.


Some speculations from scientists about Pluto data

Using the images and data so far received from New Horizons, planetary scientists outline some of their tentative conclusions as well as speculate about what it means.

[Alan Stern, New Horizons’ principal investigator] says Pluto’s surface appears to be much less heavily cratered than its large moon, Charon—which implies that the surface has been paved over in some way. That smoothing process could come from internal heat that keeps rock and ice soft, or by the frosts that snow down and blanket the surface in fresh ice. “Either [Pluto’s] internal engine continues to run, and there are active processes that are taking place,” Stern says, “or those atmospheric processes are themselves covering up the geology, and covering up the craters.”

Jonathan Lunine, a planetary scientist at Cornell University, not on the New Horizons team, favors the latter explanation. His initial impression is that Pluto is far more cratered than Triton, the moon of Neptune that is about the same size as Pluto and is thought to be a captured Kuiper belt object. Triton has a famous “cantaloupe” terrain, thought to have formed as heat, driven by Saturn’s tidal pull, allowed molten blobs of ice to rise and overturn. Parts of Pluto’s rugged surface seem to be far more carved and cratered, Lunine says. “It’s telling me that [Pluto’s] crust was not heated and modified to the extent that it was on Triton.”

Above all, however, I like Lunine’s comment at the end of the article:

Lunine says the emerging diversity on Pluto—of both active atmospheric and geological processes—makes him disagree with the decision of International Astronomical Union to call Pluto a dwarf. “This really is a planet,” he says. He notes that electrons have a double definition as a particle and a wave. “Why can’t we call Pluto a planet and a Kuiper belt object?” he asks. “I think we have to think of it as both.”


Pluto just before close encounter

Pluto just before close encounter

Today’s cool image, on the right, is the last one New Horizons sent back to Earth before its July 14th close encounter. Be sure you click here to see the full resolution version. It is quite spectacular. It was taken from about 476,000 miles, about twice the distance to the Moon.

The quality of this image strongly suggests that all will go well with the encounter today. However,

Per the plan, the spacecraft currently is in data-gathering mode and not in contact with flight controllers at the Johns Hopkins University Applied Physical Laboratory (APL) in Laurel, Maryland. Scientists are waiting to find out whether New Horizons “phones home,” transmitting to Earth a series of status updates that indicate the spacecraft survived the flyby and is in good health. The “call” is expected shortly after 9 p.m. tonight.

So, at 9 pm (Eastern) we will hear from New Horizons on its status. Images and data from the encounter itself however will arrive over time, beginning tonight and continuing throughout the coming months.


The size of Pluto pinned down

Data from New Horizons has allowed scientists to more firmly determine, for the first time, Pluto’s precise size.

Mission scientists have found Pluto to be 1,473 miles (2,370 kilometers) in diameter, somewhat larger than many prior estimates. Images acquired with the Long Range Reconnaissance Imager (LORRI) were used to make this determination. This result confirms what was already suspected: Pluto is larger than all other known solar system objects beyond the orbit of Neptune. “The size of Pluto has been debated since its discovery in 1930. We are excited to finally lay this question to rest,” said mission scientist Bill McKinnon, Washington University, St. Louis.

Pluto’s newly estimated size means that its density is slightly lower than previously thought, and the fraction of ice in its interior is slightly higher. Also, the lowest layer of Pluto’s atmosphere, called the troposphere, is shallower than previously believed.

This means that Pluto is at this moment the largest Kuiper Belt object so far known, bigger than Eris, the Kuiper Belt planet discovered in 2005 that had been thought to be bigger than Pluto and whose existence was used by some to demote Pluto’s status as a planet.

I say, they are both planets, because they are both heavy enough for gravity to have forced them to become spherical.


Pluto on July 11

Pluto on July 11

Another cool image for Monday morning: As the spacecraft zooms towards its Tuesday fly-by, it continues to take images of Pluto, even as the planet rotates. For example, compare today’s image on the right with the one I posted yesterday. You can see some of the same features (the donut-like, crater-like feature is the most obvious), but their positions are different because of the planet’s six-day rotation.

Note also that the row of black spots along the equator show more details. Not unexpectedly, they are not as simple as the early fuzzy images suggested. Unfortunately, we will not get to see even more details, as these features will not be in view during the fly-by.

Update: See this link for a new image of Charon.

More and more to come!


The last image of Pluto’s opposition hemisphere

Pluto's opposition hemisphere

Cool image time! The New Horizons team has released the best image they are ever going to get of the hemisphere that will be facing away from the spacecraft when it does its fly-by on July 14.

The spots appear on the side of Pluto that always faces its largest moon, Charon—the face that will be invisible to New Horizons when the spacecraft makes its close flyby the morning of July 14. New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado, describes this image as “the last, best look that anyone will have of Pluto’s far side for decades to come.”

The spots are connected to a dark belt that circles Pluto’s equatorial region. What continues to pique the interest of scientists is their similar size and even spacing. “It’s weird that they’re spaced so regularly,” says New Horizons program scientist Curt Niebur at NASA Headquarters in Washington. Jeff Moore of NASA’s Ames Research Center, Mountain View, California, is equally intrigued. “We can’t tell whether they’re plateaus or plains, or whether they’re brightness variations on a completely smooth surface.”

No one will likely have the answers to these questions for a long time, as it might take as long as a half century before before anyone can get another spacecraft there.


Another new Pluto image

Pluto geology

Cool image time! The New Horizons science team released another image of Pluto on Friday, this time showing enough details that they can begin to see geological features.

New Horizons’ latest image of Pluto was taken on July 9, 2015 from 3.3 million miles (5.4 million kilometers) away, with a resolution of 17 miles (27 kilometers) per pixel. At this range, Pluto is beginning to reveal the first signs of discrete geologic features. This image views the side of Pluto that always faces its largest moon, Charon, and includes the so-called “tail” of the dark whale-shaped feature along its equator. (The immense, bright feature shaped like a heart had rotated from view when this image was captured.)

“Among the structures tentatively identified in this new image are what appear to be polygonal features; a complex band of terrain stretching east-northeast across the planet, approximately 1,000 miles long; and a complex region where bright terrains meet the dark terrains of the whale,” said New Horizons principal investigator Alan Stern.

Be sure to click on the link to see the full resolution version of the image.


New image of Pluto and Charon

Pluto and Charon

The New Horizons science team today released a new image showing both Pluto and Charon, and not unexpectedly, they are very different from each other.

A high-contrast array of bright and dark features covers Pluto’s surface, while on Charon, only a dark polar region interrupts a generally more uniform light gray terrain. The reddish materials that color Pluto are absent on Charon. Pluto has a significant atmosphere; Charon does not. On Pluto, exotic ices like frozen nitrogen, methane, and carbon monoxide have been found, while Charon’s surface is made of frozen water and ammonia compounds. The interior of Pluto is mostly rock, while Charon contains equal measures of rock and water ice. “These two objects have been together for billions of years, in the same orbit, but they are totally different,” said Principal Investigator Alan Stern of the Southwest Research Institute (SwRI), Boulder, Colorado.

For a half century, since the first probes left Earth to visit other worlds, the one consistent axiom we have learned from every mission is that no two objects are going to be alike, and that every object out there is going to be incredibly unique. Pluto and Charon, in finishing the human race’s first inventory of the solar system, prove this axiom once again.


Best image yet of Pluto


Very cool image time! The New Horizons science team today released [link fixed] their best image yet of Pluto, taken on July 7 immediately following the spacecraft’s recovery from safe mode.

This view is centered roughly on the area that will be seen close-up during New Horizons’ July 14 closest approach. This side of Pluto is dominated by three broad regions of varying brightness. Most prominent are an elongated dark feature at the equator, informally known as “the whale,” and a large heart-shaped bright area measuring some 1,200 miles (2,000 kilometers) across on the right. Above those features is a polar region that is intermediate in brightness.

For the first time these features look like actual surface areas on a planet, not fuzzy blobs. We are still seeing Pluto like we saw all planets prior to the space age, but at least now we know what we are looking at.


A New Horizons map of Pluto

New Horizons map of Pluto

Cool image time! The New Horizons science team today released their best global map of Pluto, as seen so far.

The center of the map shows the area that New Horizons will see close-up during the fly-by.

The elongated dark area informally known as “the whale,” along the equator on the left side of the map, is one of the darkest regions visible to New Horizons. It measures some 1,860 miles (3,000 kilometers) in length. Directly to the right of the whale’s “snout” is the brightest region visible on the planet, which is roughly 990 miles (1,600 kilometers) across. This may be a region where relatively fresh deposits of frost—perhaps including frozen methane, nitrogen and/or carbon monoxide—form a bright coating.

Continuing to the right, along the equator, we see the four mysterious dark spots that have so intrigued the world, each of which is hundreds of miles across. Meanwhile, the whale’s “tail,” at the left end of the dark feature, cradles a bright donut-shaped feature about 200 miles (350 kilometers) across. At first glance it resembles circular features seen elsewhere in the solar system, from impact craters to volcanoes. But scientists are holding off on making any interpretation of this and other features on Pluto until more detailed images are in hand.

Some of these features will not be resolved much clearer than this, as Pluto’s day is six Earth days long, and will thus not be visible any longer to the spacecraft during its last week approach. In addition, much of the southern hemisphere will also not be imaged at all, as the planet’s inclination puts much of that hemisphere out of view entirely.

Nonetheless, we will see a great deal that has never been seen before. Stay tuned!


New Horizons team proposes cool names for Charon and Pluto features

In anticipation of their discovering many previously unseen features on both Pluto and Charon, the New Horizons science team released today a proposed list of names, including “Kirk”, “Spock”, and many other fictional science fiction characters.

Many of these suggestions were proposed by the public. Personally, I prefer the part of their proposal where they suggest naming features after real people, like Lewis Carroll and Arthur Clarke.


All A-OK with New Horizons

Engineers have pinpointed the issue — “a hard-to-detect timing flaw in the spacecraft command sequence” — that caused New Horizons to enter safe mode on Saturday.

Since they do not plan to upload any similar commands before the July 14th fly-by, they do not expect a repeat of this problem. Full science operations are expected to resume on July 7.


New Horizons temporarily loses contact with Earth

Engineers lost contact with New Horizons for an hour and twenty-one minutes on Saturday.

Engineers have since begun talking with the probe again, but NASA says it will take up to several days to get New Horizons back to normal. In the meantime, the US$700-million spacecraft is not recording science data. It is just 11 million kilometres from Pluto, and closing in fast.

Communication issues are exacerbated by the fact that it takes four and a half hours to send a signal, traveling at light speed, across the nearly 4.8 billion kilometres to the spacecraft — and four and a half hours back. In that elapsed time, the Earth has rotated so much that mission controllers must switch from one to another of the three deep-space antennas that communicate with spacecraft: in Goldstone, California; Canberra; and Madrid.


What we will and will not see during the Pluto fly-by

Pluto's two hemispheres

The images above, released today by the New Horizons’ science team, provide the best global view so far of Pluto’s two hemispheres. I have cropped and rearranged the original to focus on Pluto.

The images illustrate some basic new knowledge about the planet. For one, scientists have now identified the planet’s poles, based upon its rotation. While scientists had had a very rough vague idea of Pluto’s rotation and inclination beforehand, they have now pinned it down pretty precisely.

The images also show the planet’s most striking and unique features, though not with enough resolution to tell us what they are.

New color images from NASA’s New Horizons spacecraft show two very different faces of the mysterious dwarf planet, one with a series of intriguing spots along the equator that are evenly spaced. Each of the spots is about 300 miles in diameter, with a surface area that’s roughly the size of the state of Missouri.

Scientists have yet to see anything quite like the dark spots; their presence has piqued the interest of the New Horizons science team, due to the remarkable consistency in their spacing and size. While the origin of the spots is a mystery for now, the answer may be revealed as the spacecraft continues its approach to the mysterious dwarf planet. “It’s a real puzzle—we don’t know what the spots are, and we can’t wait to find out,” said New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder. “Also puzzling is the longstanding and dramatic difference in the colors and appearance of Pluto compared to its darker and grayer moon Charon.”

This image release also shows us what we will and will not see during the fly-by. The image on the left is the “encounter hemisphere.” This is the hemisphere that will be in view during New Horizons’ July 14 fly-by. We shall get very nice high resolutions of much of this hemisphere.

The other hemisphere, however, will not be facing us during the fly-by. Unless that can get some high resolution images before it rotates out of view, the row of large dark spots at the equator will remain a mystery.

The images also suggest that, because of Pluto’s tilt, much of the southern hemisphere is not going to be seen at all. It will remain an additional mystery for the many decades that are going to pass before another spacecraft finally returns to this distant place.


New Horizons gets closer

Pluto and Charon

Cool image time! Even as the engineers successfully completed last night their last course correction engine burn, the New Horizons science team released an image showing both Pluto and Charon.

The 23-second thruster burst was the third and final planned targeting maneuver of New Horizons’ approach phase to Pluto; it was also the smallest of the nine course corrections since New Horizons launched in January 2006. It bumped the spacecraft’s velocity by just 27 centimeters per second – about one-half mile per hour – slightly adjusting its arrival time and position at a flyby close-approach target point approximately 7,750 miles (12,500 kilometers) above Pluto’s surface.

The image, which I have cropped to focus on the planets, is still somewhat fuzzy, though it also shows the increasing sharpness as the spacecraft gets closer.

Only two weeks to go!


Finding Pluto is really New Horizon’s biggest problem

As New Horizons speeds towards its planned fly-by of Pluto on July 14, the biggest problem faced by its engineers is making sure the spacecraft actually finds and photographs the planet.

Because astronomers discovered the dwarf planet in 1930, they have seen only part of its 248-year path around the Sun, and they don’t know exactly where Pluto is. And New Horizons is so far from Earth that it takes 9 hours to send and receive a signal, making the spacecraft hard to direct in real time. “Everything is pushed to the extreme,” says Bobby Williams, an engineer at KinetX Aerospace in Simi Valley, California, who heads the mission’s navigation team.

This fact, which has not been mentioned previously as far as I remember, suggests that there is a good chance that New Horizons might fly through its planned window and aim its cameras at the wrong spot in the sky, missing Pluto entirely. It also explains partly why the images released so far have been so fuzzy: They are focused mostly on doing navigation work, and are taking wide angle shots to make sure they catch Pluto in their picture frame. Zooming in too close might actually miss Pluto as they don’t exactly know where it is.

All this only makes the July 14th fly-by even more exciting. Let us hope they do due diligence and get the pictures we all want!


New images of Pluto

Latest Pluto images

Cool image time! The two images on the right, taken on June 18 and June 15 respectively, — cropped from a larger collection — show Pluto’s two hemispheres, as best as New Horizons can at the moment resolve them.

While still as fuzzy as pre-space age planetary images, the pictures when compared with earlier images of the same hemispheres now clearly show several consistent features.

Things can only get better. Stay tuned!


Another successful course correction for New Horizons

New Horizons has successfully completed another course correction and is shipshape for its fly-by of Pluto on July 14.

A 45-second thruster burst on June 14 refined New Horizons’ trajectory toward Pluto, targeting the optimal aim point for the spacecraft’s flight through the Pluto system. This was only the second targeting maneuver of New Horizons’ approach to Pluto; Sunday’s burst adjusted the spacecraft’s velocity by just 52 centimeters per second, aiming it toward the desired close-approach target point approximately 7,750 miles above Pluto’s surface.

The maneuver was based on the latest radio tracking data on the spacecraft and range-to-Pluto measurements made by optical-navigation imaging of the Pluto system taken by New Horizons in recent weeks.

Right now all looks good for the fly-by.


New images from New Horizons of Pluto

Images taken by New Horizons over a four day period at the end of May show Pluto to be a planet with distinct areas of bright and dark.

The images are still very fuzzy and require a great deal of processing to tease out the detail that is seen. If anything, they resemble images of Mars taken from Earth before the space age. Thus, one must treat these the dark and light areas with great skepticism. We are seeing evidence of different surface topography and geology, but to pin it down more precisely at this time would be a mistake. The spacecraft has to get closer for us to know better what we are seeing.


Pluto’s moons rotate chaotically

Data from the Hubble Space Telescope has determined that two and maybe more of Pluto’s moons have chaotic rotations.

In a surprising new study, it has been found that two of Pluto’s moons, Nix and Hydra, are in a chaotic rotation. This means that an observer on Pluto would not see the same face of the moons from one night to the next. For visitors on the moons themselves, things would get even more confusing, as every day would be a different length to the one that preceded it. The other two moons studied, Kerberos and Styx, will likely be found to be chaotic too, pending further study.

This would also mean that you would not know where on the horizon the sun or Pluto would rise each day.

This information was gathered partly to help New Horizons prepare for its July 14 fly-by.


New Images of Pluto from New Horizons

Pluto in mid-May

Cool image time! New images taken by New Horizons of Pluto in mid-May have begun showing faint details of the planet’s surface.

“These new images show us that Pluto’s differing faces are each distinct; likely hinting at what may be very complex surface geology or variations in surface composition from place to place,” said New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute in Boulder, Colorado. “These images also continue to support the hypothesis that Pluto has a polar cap whose extent varies with longitude; we’ll be able to make a definitive determination of the polar bright region’s iciness when we get compositional spectroscopy of that region in July.”

These images also suggest vaguely that Pluto might not be entire spherical, but I wouldn’t put much money on that speculation. We will know for sure in just a few more weeks.


New Horizons spots all of Pluto’s 5 known moons

New Horizons has now been able to image all of Pluto’s known moons.

Pluto’s five known satellites are Charon, Hydra, Nix, Kerberos and Styx. At 648 miles (1,043 km) in diameter, Charon is nearly half as wide as Pluto itself, but the other four moons are minuscule. Kerberos and Styx, for example, are thought to be just 4 to 13 miles (7 to 21 km) and 6 to 20 miles (10 to 32 km) wide, respectively.

That the spacecraft has been able to spot them all this soon bodes well for what it will see when if flies past Pluto in July.


A review of what little we know of Pluto prior to New Horizons’ arrival

The principle investigator of the New Horizons mission to Pluto gives us an overview of what is known, and what we might find, when the spacecraft does its fly-by on July 14.

Pluto has very distinct surface markings, including apparent polar caps, and it has an atmosphere (mostly nitrogen). We know that Pluto’s interior is primarily made of rock — about 70% by mass. Also, Pluto-Charon constitute a true binary planet, with a barycenter (center of mass) situated in the open space between them. We know Charon is a “rising star” among the solar system’s icy bodies, with evidence for recently created surface ices, possible internal activity (hinted at by the spectroscopic discovery of ammonium hydrates a few years ago), and some likelihood of an atmosphere itself — perhaps gas that was siphoned off Pluto! As for the small satellites — Styx, Nix, Kerberos, and Hydra — we know very little about them beyond their orbits and crude colors. Soon all six of those points of light, planet and moons, will be real worlds thanks to NASA’s New Horizons.

He also admits that trying to guess what we might find is quite hazardous, and likely will end up wrong.

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