It Took 15 Months, but all of New Horizons’ Data Has Finally Been Downloaded

New Horizon's July 2015 flyby of Pluto captured this iconic image of the heart-shaped region called Tombaugh Regio. Credit: NASA/JHUAPL/SwRI.

Finally, the New Horizons team has their entire “pot of gold.” 15 months after the mission’s flyby of the Pluto system, the final bits of science data from the historic July 2015 event has been safely transmitted to Earth.

“The New Horizons mission has required patience for many years, but we knew the results would be well worth the wait,” New Horizons project scientists Hal Weaver told me earlier this year.

Because of New Horizons’ great distance from Earth and the spacecraft’s low power output (the spacecraft runs on just 2-10 watts of electricity), it has a relatively low ‘downlink’ rate at which data can be transmitted to Earth, just 1-4 kilobits per second. That’s why it has taken so long to get all the science data back to Earth.

Pluto Explored! In 2006, NASA placed a 29-cent 1991 ‘Pluto: Not Yet Explored’ stamp in the New Horizons spacecraft. With the new stamp, the Postal Service recognizes the first reconnaissance of Pluto in 2015 by NASA’s New Horizon mission. The two separate stamps show an artists’ rendering of the New Horizons spacecraft and the spacecraft’s enhanced color image of Pluto taken near closest approach. Credits: USPS/Antonio Alcalá © 2016 USPS
Pluto Explored! In 2006, NASA placed a 29-cent 1991 ‘Pluto: Not Yet Explored’ stamp in the New Horizons spacecraft. With the new stamp, the Postal Service recognizes the first reconnaissance of Pluto in 2015 by NASA’s New Horizon mission. The two separate stamps show an artists’ rendering of the New Horizons spacecraft and the spacecraft’s enhanced color image of Pluto taken near closest approach.
Credits: USPS/Antonio Alcalá © 2016 USPS

“This is what we came for – these images, spectra and other data types that are going to help us understand the origin and the evolution of the Pluto system for the first time,” New Horizons principal investigator Alan Stern said a few months ago during an interview. “We’re seeing that Pluto is a scientific wonderland. The images have been just magical. It’s breathtaking.”

Because it was a flyby, and the spacecraft had just one chance at gathering data from Pluto, New Horizons was designed to gather as much data as it could, as quickly as it could – taking about 100 times more data on close approach to Pluto and its moons than it could have sent home before flying onward. The spacecraft was programmed to send select, high-priority datasets home in the days just before and after close approach, and began returning the vast amount of remaining stored data in September 2015.

New Horizons is now over 3.1 billion miles (5 billion km) away from Earth as it continues its journey through the Kuiper Belt. That translates to a current radio signal delay time of five hours, eight minutes at light speed.
The science team created special software to keep track of all the data sets and schedule when they would be returned to Earth.

New Horizons was about 3.7 million miles (6 million kilometers) from Pluto and Charon when it snapped this portrait late on July 8, 2015. Credits: NASA-JHUAPL-SWRI
New Horizons was about 3.7 million miles (6 million kilometers) from Pluto and Charon when it snapped this portrait late on July 8, 2015.
Credits: NASA-JHUAPL-SWRI

The final item that was received was a portion of a Pluto-Charon observation sequence taken by the Ralph/LEISA imager. It arrived at New Horizons’ mission operations at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, at 5:48 a.m. EDT on Oct. 25. The downlink came via NASA’s Deep Space Network station in Canberra, Australia. It was the last of the 50-plus total gigabits of Pluto system data transmitted to Earth by New Horizons over the past 15 months.

“We have our pot of gold,” said Mission Operations Manager Alice Bowman, of APL.

Bowman also said the team will conduct a final data-verification review of New Horizons two onboard recorders before sending commands to erase all the data on the spacecraft. New Horizons has more work to do, so erasing the “old” data will clear space for new data to be taken during its Kuiper Belt Extended Mission (KEM). The spacecraft will do a series of distant Kuiper Belt object observations as well as perform a close encounter flyby with with a small Kuiper Belt object, 2014 MU69, on Jan. 1, 2019.

“There’s a great deal of work ahead for us to understand the 400-plus scientific observations that have all been sent to Earth,” said Stern. “And that’s exactly what we’re going to do—after all, who knows when the next data from a spacecraft visiting Pluto will be sent?”

You can see all of New Horizons images at the New Horizons/APL website.

Latest Results from New Horizons: Clouds on Pluto, Landslides on Charon

This image of haze layers above Pluto’s limb was taken by the Ralph/Multispectral Visible Imaging Camera (MVIC) on NASA’s New Horizons spacecraft. About 20 haze layers are seen; the layers have been found to typically extend horizontally over hundreds of kilometers, but are not strictly parallel to the surface. For example, scientists note a haze layer about 3 miles (5 kilometers) above the surface (lower left area of the image), which descends to the surface at the right. Credit: NASA/JHUAPL/SwRI.

By the end of this week, all the data gathered by the New Horizons spacecraft during its July 2015 flyby of the Pluto system will have finished downloading to Earth and be in the hands of the science team. Bonnie Buratti, a science team co-investigator said they have gone from being able to look at the pretty pictures to doing the hard work required to study the data. During today’s press briefing from the Division of Planetary Sciences conference, the New Horizons team shared a few interesting and curious findings they’ve found in the data so far.

While the famous global view of Pluto appears to show a cloud-free dwarf planet, Principal investigator Alan Stern said the team has now take a closer look and found handful of potential clouds in images taken with New Horizons’ cameras.

“Clouds are common in the atmospheres of the solar system,” Stern said during the briefing, “ and a natural question was whether Pluto, with a nitrogen atmosphere, has any clouds.”

Stern said they’ve known since flyby that Pluto has haze layers, as seen in the backlit lead image above, as New Horizons flew away from Pluto. “They stretch more than 200 km into the sky, and we’ve counted over two dozen concentric layers,” he said.

While hazes are not clouds, Stern said they have identified candidates for clouds in high-phase images from the Long Range Reconnaissance Imager and the Multispectral Visible Imaging Camera.

Candidates for possible clouds on Pluto, in images from the New Horizons Long Range Reconnaissance Imager and Multispectral Visible Imaging Camera, during the spacecraft's July 2015 flight through the Pluto system. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
Candidates for possible clouds on Pluto, in images from the New Horizons Long Range Reconnaissance Imager and Multispectral Visible Imaging Camera, during the spacecraft’s July 2015 flight through the Pluto system. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

“The seven candidates are all similar in that they are very low altitude,” Stern said, and they are all low-lying, isolated small features, so no broad cloud decks or fields. When we map them over the surface, they all lie near the terminator, so they occur near dawn or dusk. This is all suggestive they are clouds because low-lying regions and dawn or dusk provide cooler conditions where clouds may occur.”

Stern told Universe Today that these possible, rare condensation clouds could be made of ethane, acetylene, hydrogen cyanide or methane under the right conditions. Stern added these clouds are probably short-lived phenomena – again, likely occurring only at dawn or dusk. A day on Pluto is 6.4 days on Earth.

“But if there are clouds, it would mean the weather on Pluto is even more complex than we imagined,” Stern said.

Disappointingly, the New Horizons team has no way of confirming if these are clouds or not. “None of them can be confirmed as clouds because they are very low lying and we don’t have stereo images to tell us more,” Stern said, adding that the only way to confirm if there are condensation clouds on Pluto would be to return with an orbiter mission.

Landslides on Charon

Signs of a long run-out landslide on Pluto's largest moon, Charon. This perspective view of Charon's informally named Serenity Chasm shows a 200-meter thick lobate landslide that runs up against a 6 km high ridge. The images were taken by New Horizons, Long Range Reconnaissance Imager (LORRI) and Multispectral Visible Imaging Camera (MVIC) during the spacecraft’s July 2015 flyby of the Pluto system. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
Signs of a long run-out landslide on Pluto’s largest moon, Charon. This perspective view of Charon’s informally named Serenity Chasm shows a 200-meter thick lobate landslide that runs up against a 6 km high ridge. The images were taken by New Horizons, Long Range Reconnaissance Imager (LORRI) and Multispectral Visible Imaging Camera (MVIC) during the spacecraft’s July 2015 flyby of the Pluto system. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

While Pluto shows many kinds of activity, one surface process scientists haven’t seen on the dwarf planet is landslides. Surprisingly, though, they have been spotted on Pluto’s largest moon, Charon.

“We’ve seen similar landslides on other rocky and icy planets, such as Mars and Saturn’s moon Iapetus, but these are the first landslides we’ve seen this far from the sun, in the Kuiper Belt,” said Ross Beyer, a science team researcher from Sagan Center at the SETI Institute and NASA Ames Research Center, California. “The big question is will they be detected elsewhere in the Kuiper Belt?”

Long runout landslides seen on Charon’s Serenity Chasm shows a 200-meter thick lobate landslide that runs up against a 6 km high ridge.

“With our images, we can just resolve a smooth apron and the deposit as a whole,” said Beyer, “we can’t see individual grains. But given the cold conditions on Charon, the deposit likely made of boulders of ice and rock.”

Beyer said earthquakes or an impact could have jump started the landslide on regions that were ready to slide. “The boulders may have melted and the edges and got slippery enough to begin to slide down the slope,” he said.

The images of Serenity Chasma were taken by New Horizons’ Long Range Reconnaissance Imager (LORRI) on July 14, 2015, from a distance of 48,912 miles (78,717 kilometers).

Beyer added that while Pluto doesn’t have landslides, it does have material that appears to be moving downhill as rock falls and glacier-like flows.

Scientists from NASA's New Horizons mission have spotted signs of long run-out landslides on Pluto's largest moon, Charon. Arrows mark indications of landslide activity. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.
Scientists from NASA’s New Horizons mission have spotted signs of long run-out landslides on Pluto’s largest moon, Charon. Arrows mark indications of landslide activity. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

Bright and active

New Horizons data shows that portions of Pluto’s large heart-shaped region, Sputnik Planitia, are among the most reflective in the solar system. “That brightness indicates surface activity,” said Buratti, “similar to how Saturn’s moon Enceladus is very reflective, about 100% reflective, and is very active with plumes and geysers. Because we see a pattern of high surface reflectivity equating to activity, we can infer that the dwarf planet Eris, which is known to be highly reflective, is also likely to be active.”

Next Target

New Horizons is now making a beeline for its next target, KBO 2014 MU69. Cameras on the New Horizons spacecraft have been taking long range images and MU69 is the smallest KBO to have its color measured: it has a reddish tint. Scientists have used that data to confirm this object is part of the so-called cold classical region of the Kuiper Belt, which is believed to contain some of the oldest, most prehistoric material in the solar system.

“The reddish color tells us the type of Kuiper Belt object 2014 MU69 is,” said Amanda Zangari, a New Horizons post-doctoral researcher from Southwest Research Institute. “The data confirms that on New Year’s Day 2019, New Horizons will be looking at one of the ancient building blocks of the planets.”

Zangari added that they will be using the Hubble Space Telescope to better understand MU69.

“We would like to use Hubble to its find rotation rate and better understand its shape, as far as planning,” she said. “We would like to know ahead of time, if it is oblong, we would like to fly when the longest point is facing the telescope.”

Several times during the briefing, Stern indicated how having a future mission that orbited Pluto would answer so many outstanding questions the team has. He outlined one potential mission that is in the very earliest stages of study where a spacecraft could be launched on NASA’s upcoming Space Launch System (SLS) and the spacecraft could have an RTG-powered ion engine that would allow a fast-moving spacecraft the ability to slow down and go into orbit (unlike New Horizons). This type of architecture would allow for a flight time of 7.5 years to Pluto, quicker than New Horizons’ nearly 9.5 years.

More than 100 km of Liquid Water Beneath Pluto’s Surface

New Horizon's July 2015 flyby of Pluto captured this iconic image of the heart-shaped region called Tombaugh Regio. Credit: NASA/JHUAPL/SwRI.

What lies beneath Pluto’s icy heart? New research indicates there could be a salty “Dead Sea”-like ocean more than 100 kilometers thick.

“Thermal models of Pluto’s interior and tectonic evidence found on the surface suggest that an ocean may exist, but it’s not easy to infer its size or anything else about it,” said Brandon Johnson from Brown University. “We’ve been able to put some constraints on its thickness and get some clues about composition.”

Research by Johnson and his team focused Pluto’s “heart” – a region informally called Sputnik Planum, which was photographed by the New Horizons spacecraft during its flyby of Pluto in July of 2015.

New Horizons’ Principal Investigator Alan Stern called Sputnik Planum “one of the most amazing geological discoveries in 50-plus years of planetary exploration,” and previous research showed the region appears to be constantly renewed by current-day ice convection.

Like a cosmic lava lamp, a large section of Pluto's icy surface in Sputnik Planum is being constantly renewed by a process called convection that replaces older surface ices with fresher material. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.
Like a cosmic lava lamp, a large section of Pluto’s icy surface in Sputnik Planum is being constantly renewed by a process called convection that replaces older surface ices with fresher material. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

The heart is a 900 km wide basin — bigger than Texas and Oklahoma combined — and at least the western half of it appears to have been formed by an impact, likely by an object 200 kilometers across or larger.

Johnson and colleagues Timothy Bowling of the University of Chicago and Alexander Trowbridge and Andrew Freed from Purdue University modeled the impact dynamics that created a massive crater on Pluto’s surface and also looked at the dynamics between Pluto and its moon Charon.

The two are tidally locked with each other, meaning they always show each other the same face as they rotate. Sputnik Planum sits directly on the tidal axis linking the two worlds. That position suggests that the basin has what’s called a positive mass anomaly — it has more mass than average for Pluto’s icy crust. As Charon’s gravity pulls on Pluto, it would pull proportionally more on areas of higher mass, which would tilt the planet until Sputnik Planum became aligned with the tidal axis.

So instead of being a hole in the ground, the crater actually has been filled back in. Part of it has been filled in by the convecting nitrogen ice. While that ice layer adds some mass to the basin, it isn’t thick enough on its own to make Sputnik Planum have positive mass.

The Mountainous Shoreline of Sputnik Planum on Pluto. Great blocks of Pluto’s water-ice crust appear jammed together in the informally named al-Idrisi mountains. Some mountain sides appear coated in dark material, while other sides are bright. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.
The Mountainous Shoreline of Sputnik Planum on Pluto. Great blocks of Pluto’s water-ice crust appear jammed together in the informally named al-Idrisi mountains. Some mountain sides appear coated in dark material, while other sides are bright. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

The rest of that mass, Johnson said, may be generated by a liquid lurking beneath the surface.

Johnson and his team explained it like this:

Like a bowling ball dropped on a trampoline, a large impact creates a dent on a planet’s surface, followed by a rebound. That rebound pulls material upward from deep in the planet’s interior. If that upwelled material is denser than what was blasted away by the impact, the crater ends up with the same mass as it had before the impact happened. This is a phenomenon geologists refer to as isostatic compensation.

Water is denser than ice. So if there were a layer of liquid water beneath Pluto’s ice shell, it may have welled up following the Sputnik Planum impact, evening out the crater’s mass. If the basin started out with neutral mass, then the nitrogen layer deposited later would be enough to create a positive mass anomaly.

“This scenario requires a liquid ocean,” Johnson said. “We wanted to run computer models of the impact to see if this is something that would actually happen. What we found is that the production of a positive mass anomaly is actually quite sensitive to how thick the ocean layer is. It’s also sensitive to how salty the ocean is, because the salt content affects the density of the water.”

The models simulated the impact of an object large enough to create a basin of Sputnik Planum’s size hitting Pluto at a speed expected for that part in the solar system. The simulation assumed various thicknesses of the water layer beneath the crust, from no water at all to a layer 200 kilometers thick.

The scenario that best reconstructed Sputnik Planum’s observed size depth, while also producing a crater with compensated mass, was one in which Pluto has an ocean layer more than 100 kilometers thick, with a salinity of around 30 percent.

“What this tells us is that if Sputnik Planum is indeed a positive mass anomaly —and it appears as though it is — this ocean layer of at least 100 kilometers has to be there,” Johnson said. “It’s pretty amazing to me that you have this body so far out in the solar system that still may have liquid water.”

Johnson he and other researchers will continue study the data sent back by New Horizons to get a clearer picture Pluto’s intriguing interior and possible ocean.

Further reading: Brown University, New Horions/APL

NASA Approves New Horizons Extended KBO Mission, Keeps Dawn at Ceres

New Horizons trajectory and the orbits of Pluto and 2014 MU69.
New Horizons trajectory and the orbits of Pluto and 2014 MU69.
New Horizons trajectory and the orbits of Pluto and 2014 MU69.

In an ‘Independence Day’ gift to a slew of US planetary research scientists, NASA has granted approval to nine ongoing missions to continue for another two years this holiday weekend.

The biggest news is that NASA green lighted a mission extension for the New Horizons probe to fly deeper into the Kuiper Belt and decided to keep the Dawn probe at Ceres forever, rather than dispatching it to a record breaking third main belt asteroid.

And the exciting extension news comes just as the agency’s Juno probe is about to ignite a do or die July 4 fireworks display to achieve orbit at Jupiter – detailed here.

“Mission approved!” the researchers gleefully reported on the probes Facebook and Twitter social media pages.

“Our extended mission into the #KuiperBelt has been approved. Thanks to everyone for following along & hopefully the best is yet to come.

Dwarf planet Ceres is shown in this false-color renderings, which highlight differences in surface materials.  The image is centered on Ceres brightest spots at Occator crater. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Dwarf planet Ceres is shown in this false-color renderings, which highlight differences in surface materials. The image is centered on Ceres brightest spots at Occator crater. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The New Horizons spacecraft will now continue on course in the Kuiper Belt towards an small object known as 2014 MU69, to carry out the most distant close encounter with a celestial object in human history.

“Here’s to continued success!”

The spacecraft will rendezvous with the ancient rock on New Year’s Day 2019.

Researchers say that 2014 MU69 is considered as one of the early building blocks of the solar system and as such will be invaluable to scientists studying the origin of our solar system how it evolved.

It was almost exactly one year ago on July 14, 2015 that New Horizons conducted Earth’s first ever up close flyby and science reconnaissance of Pluto – the most distant planet in our solar system and the last of the nine planets to be explored.

Pluto Explored at Last. 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
Pluto Explored at Last. 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

The immense volume of data gathered continues to stream back to Earth every day.

“The New Horizons mission to Pluto exceeded our expectations and even today the data from the spacecraft continue to surprise,” said NASA’s Director of Planetary Science Jim Green at NASA HQ in Washington, D.C.

“We’re excited to continue onward into the dark depths of the outer solar system to a science target that wasn’t even discovered when the spacecraft launched.”

This new global mosaic view of Pluto was created from the latest high-resolution images to be downlinked from NASA’s New Horizons spacecraft and released on Sept. 11, 2015. The images were taken as New Horizons flew past Pluto on July 14, 2015, from a distance of 50,000 miles (80,000 kilometers). This new mosaic was stitched from over two dozen raw images captured by the LORRI imager and colorized. Annotated with informal place names. Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Marco Di Lorenzo/Ken Kremer/kenkremer.com
This new global mosaic view of Pluto was created from the latest high-resolution images to be downlinked from NASA’s New Horizons spacecraft and released on Sept. 11, 2015. The images were taken as New Horizons flew past Pluto on July 14, 2015, from a distance of 50,000 miles (80,000 kilometers). This new mosaic was stitched from over two dozen raw images captured by the LORRI imager and colorized. Annotated with informal place names. Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Marco Di Lorenzo/Ken Kremer/kenkremer.com

While waiting for news on whether NASA would approve an extended mission, the New Horizons engineering and science team already ignited the main engine four times to carry out four course changes in October and November 2015, in order to preserve the option of the flyby past 2014 MU69 on Jan 1, 2019.

Green noted that mission extensions into fiscal years 2017 and 2018 are not final until Congress actually passes sufficient appropriation to fund NASA’s Planetary Science Division.

“Final decisions on mission extensions are contingent on the outcome of the annual budget process.”

Tough choices were made even tougher because the Obama Administration has cut funding for the Planetary Sciences Division – some of which was restored by a bipartisan majority in Congress for what many consider NASA’s ‘crown jewels.’

NASA’s Dawn asteroid orbiter just completed its primary mission at dwarf planet Ceres on June 30, just in time for the global celebration known as Asteroid Day.

“The mission exceeded all expectations originally set for its exploration of protoplanet Vesta and dwarf planet Ceres,” said NASA officials.

The Dawn science team had recently submitted a proposal to break out of orbit around the middle of this month in order to this conduct a flyby of the main belt asteroid Adeona.

Green declined to approve the Dawn proposal, citing additional valuable science to be gathered at Ceres.

The long-term monitoring of Ceres, particularly as it gets closer to perihelion – the part of its orbit with the shortest distance to the sun — has the potential to provide more significant science discoveries than a flyby of Adeona,” he said.

The funding required for a multi-year mission to Adeona would be difficult in these cost constrained times.

However the spacecraft is in excellent shape and the trio of science instruments are in excellent health.

Dawn arrived at Ceres on March 6, 2015 and has been conducting unprecedented investigation ever since.

Dawn is Earth’s first probe in human history to explore any dwarf planet, the first to explore Ceres up close and the first to orbit two celestial bodies.

The asteroid Vesta was Dawn’s first orbital target where it conducted extensive observations of the bizarre world for over a year in 2011 and 2012.

The mission is expected to last until at least later into 2016, and possibly longer, depending upon fuel reserves.

Due to expert engineering and handling by the Dawn mission team, the probe unexpectedly has hydrazine maneuvering fuel leftover.

Dawn will remain at its current altitude at the Low Altitude Mapping Orbit (LAMO) for the rest of its mission, and indefinitely afterward, even when no further communications are possible.

Green based his decision on the mission extensions on the biannual peer review scientific assessment by the Senior Review Panel.

Dawn was launched in September 2007.

The other mission extensions – contingent on available resources – are: the Mars Reconnaissance Orbiter (MRO), Mars Atmosphere and Volatile EvolutioN (MAVEN), the Opportunity and Curiosity Mars rovers, the Mars Odyssey orbiter, the Lunar Reconnaissance Orbiter (LRO), and NASA’s support for the European Space Agency’s Mars Express mission.

Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.

Ken Kremer

Peering for Pluto: Our Guide to Opposition 2016

An enviable view, of the most distant eclipse seen yet, as New Horizons flies through the shadow of Pluto. Image credit: NASA/JPL.

What an age we live in. This summer marks the very first opposition of Pluto since New Horizons’ historic flyby of the distant world in July 2015. If you were like us, you sat transfixed during the crucial flyby phase, the climax of a decade long mission. We now live in an era where Pluto and its massive moon Charon are a known worlds, something that even Pluto discoverer Clyde Tombaugh never got to see.

Pluto in 2016

And this summer, with a little skill and patience and a good-sized telescope, you can see Pluto for yourself. Opposition 2016 sees the remote world looping through the star-rich fields of eastern Sagittarius. Hovering around declination 21 degrees south, +14.1 magnitude Pluto is higher in the June skies for observers in the southern hemisphere than the northern, but don’t let that stop you from trying. Opposition occurs on July 7th, when Pluto rises opposite from the setting Sun and rides across the meridian at 29 degrees above the southern horizon for observers based along 40 degrees north latitude at local midnight.

The general realm of Pluto in 2016. Image credit: Starry Night Education Software.
The general realm of Pluto in 2016. Image credit: Starry Night Education Software.

Pluto actually crossed the plane of the galactic equator in 2009, and won’t cross the celestial equator northward until 2109. Fun fact: astronomer Clyde Tombaugh discovered Pluto as it drifted through the constellation Gemini in 1930. Here we are 86 years later, and Pluto has only moved six zodiacal constellations along the ecliptic eastward in its 248 year orbit around the Sun.

A close up look at the path of Pluto for the remainder of 2016.
A close up look at the path of Pluto for the remainder of 2016. Note the position of New Horizons and KBO 2014 MU69 at the end of the year thrown in as well. Image credit: Starry Night Pro 7.

And Pluto is getting tougher to catch in a backyard scope, as well. The reason: Pluto passed perihelion or its closest point to the Sun in 1989 inside the orbit of Neptune, and it’s now headed out to aphelion about a century from now in 2114. Pluto is in a fairly eccentric orbit, ranging from 29.7 astronomical units (AU) to 49.4 AU from the Sun. This also means that Pluto near opposition can range from a favorable magnitude +13.7 near perihelion, to three magnitudes (16 times) fainter near aphelion hovering around magnitude +16.3. Clyde was lucky, in a way. Had Pluto been near aphelion in the 20th century rather than headed towards perihelion, it might have waited much longer for discovery.

2016 sees Pluto shining at +14.1, one magnitude (2.5 times) above the usual quoted mean. See Mars over in the constellation Libra shining at magnitude -1.5? It’s 100^3 (a 5-fold change in magnitude is equal to a factor of 100 in brightness), or over a million times brighter than Pluto.

The inner and outermost planet(?) Mercury meets Pluto earlier this year in January. Image credit and copyright: Shahrin Ahmad (@Shahgazer).
The inner and outermost planet(?) Mercury meets Pluto earlier this year in January. Image credit and copyright: Shahrin Ahmad (@Shahgazer).

You often see Pluto quoted as visible in a telescope aperture of ‘six inches or larger,’ but for the coming decade, we feel this should be amended to 8 inches and up. We once nabbed Pluto during public viewing using the 14” reflector at the Flandrau observatory.

And how about Pluto’s large moon, Charon? Shining at an even fainter +16th magnitude, Charon never strays more than 0.9” from Pluto… still, diligent amateurs have indeed caught the elusive moon… as did Wendy Clark just last year.

Pluto: imaged last year during New Horizons' historic encounter. Image credit and copyright: Wendy Clark
Pluto: imaged last year during New Horizons’ historic encounter. Image credit and copyright: Wendy Clark.

Lacking a telescope? Hey, so are we, as we trek through Morocco this summer… never fear, you can still wave in the general direction of Pluto and New Horizons on the evening of June 21st, one day after the northward solstice and the Full Moon, which passes three degrees north of Pluto.

The location of Pluto in relation to the rising Full Moon on the night of June 21st. Image credit: Stellarium.
The location of Pluto in relation to the rising Full Moon on the night of June 21st. Image credit: Stellarium.

And follow that spacecraft, as New Horizons is set to make a close pass by Kuiper Belt Object 2014 MU69 in January 2019 on New Year’s Day.

A key date to make your quest for Pluto is June 26th, when Pluto sits just 3′ minutes to the south of the +2.9 magnitude star Pi Sagittarii (Albaldah), making a great guidepost.

Does the region of Sagittarius near Pi Sagittarii sound familiar? That’s because the Wow! Signal emanated from a nearby region of the sky on August 15th, 1977. Pluto will cross the border into the constellation Capricornus in 2024.

After opposition, Pluto heads into the evening sky, towards solar conjunction on January 7th, 2017.

Observing Pluto requires patience, dark skies, and a good star chart plotted down to about +15th magnitude. One key problem: many star charts don’t go down this faint. We use Starry Night Pro 7, which includes online access to the USNO catalog and a database of 500 million stars down to magnitude +21, more than enough for most backyard scopes.

Don’t miss a chance to see Pluto for yourself this summer!

Hold On To Your Jaw. Pluto Extreme Close Up Best Yet

This mosaic of Pluto's surface was created from images taken by the New Horizons probe just 23 minutes before its closest approach. Credit: NASA/JHUAPL/SwRI

The New Horizons mission, which its conducted its historic flyby on July 14th, 2015, has yielded a wealth of scientific data about Pluto. This has included discoveries about Pluto’s size, its mountainous regions, its floating ice hills, and (more recently) how the dwarf planet interacts with solar wind – a discovery which showed that Pluto is actually more planet-like than previously thought.

But beyond revelations about the planet’s size, geography and surface features, it has also provided the most breathtaking, clear, and inspiring images of Pluto and its moons to date. And with this latest release of images taken by the New Horizon‘s Long Range Reconnaissance Imager (LORRI), people here on Earth are being treated to be the best close-up of Pluto yet.

These images, which were taken while the New Horizon’s probe was still 15,850 km (9,850 mi) away from Pluto (just 23 minutes before it made its closest approach), extend across the hemisphere that the probe was facing as it flew past. It shows features ranging from the cratered northern uplands and the mountainous regions in Voyager Terra before slicing through the flatlands of “Pluto’s Heart” – aka. Tombaugh Regio – and ending up in another stretch of rugged highlands.

. Credit: earthsky.org
Informal names given to Pluto’s surface features. Credit: earthsky.org

The width of the strip varies as the images pass from north to south, from more than 90 km (55 mi) across at the northern end to about 75 km (45 mi) at its southern point. The perspective also changes, with the view appearing virtually horizontal at the northern end and then shifting to an almost top-down view onto the surface by the end.

The crystal clear photographs that make up the mosaic – which have a resolution of about 80 meters (260 feet) per pixel – offer the most detailed view of Pluto’s surface ever. With this kind of clarity, NASA scientists are able to discern features that were never before visible, and learn things about the kinds of geological processes which formed them.

This includes the chaotic nature of the mountains in the northern hemisphere, and the varied nature of the icy nitrogen plains across Tombaugh Regio – which go from being cellular, to non-cellular, to a cross-bedding pattern. These features are a further indication that Pluto’s surface is the product of a combination of geological forces, such as cryovolcanism, sublimation, geological activity, convection between water and nitrogen ice, and interaction between the surface and atmosphere.

Four images from New Horizons’ Long Range Reconnaissance Imager (LORRI) were combined with color data from the Ralph instrument to create this global view of Pluto. Credits: NASA/JHUAPL/SwRI
Images snapped by New Horizons’ Long Range Reconnaissance Imager (LORRI) while the probe was still on approach to Pluto were combined with color data from the Ralph instrument to create this global view of Pluto. Credits: NASA/JHUAPL/SwRI

Alan Stern, the principal investigator of the New Horizons mission and the Associate Vice President of Research and Development at the Southwest Research Institute, was especially impressed with this latest find. As he told Universe Today via email:

“This new high resolution image mosaic is the complete highest resolution strip of images New Horizons obtained, and its both eye candy gorgeous and scientifically rich. Think about it— one flyby and we have this mosaic, plus so much more; no dataset like this existed on Mars until we’d flown half a dozen missions there!”

The most distant flyby in the history of space exploration, and yet we’ve obtained more from this one mission than multiple flybys were able to provide from one of Earth’s closest neighbors. Fascinating! And what’s more, new information is expected to be coming from the New Horizons probe until this coming October. To top it off, our scientists are still not finished analyzing all the information the mission collected during its flyby.

The full-resolution image can be viewed here, and be sure to enjoy this NASA video of the mosaic:

Further Reading: NASA

Take A Virtual Reality Tour Of Pluto

View from the surface of Pluto, showing its large moon Charon in the distance. Credit: New York Times

On July 14th, 2015, the New Horizons probe made history as it passed within 12,500 km (7,800 mi) of Pluto, thus making it the first spacecraft to explore the dwarf planet up close. And since this historic flyby, scientists and the astronomy enthusiasts here at Earth have been treated to an unending stream of breathtaking images and scientific discoveries about this distant world.

And thanks to the New York Times and the Universities Space Research Association‘s Lunar and Planetary Institute in Texas, it is now possible to take a virtual reality tour of Pluto. Using the data obtained by the New Horizon’s instruments, users will be able to experience what it is like to explore the planet using their smartphone or computer, or in 3D using a VR headset.

The seven-minute film, titled “Seeking Pluto’s Frigid Heart“, which is narrated by science writer Dennis Overbye of the New York Times – shows viewers what it was like to approach the dwarf planet from the point of the view of the New Horizon’s probe. Upon arrival, they are then able to explore Pluto’s surface, taking in 360 degree views of its icy mountains, heart-shaped plains, and largest moon, Charon.

This represents the most detailed and clear look at Pluto to date. A few decades ago, the few maps of Pluto we had were the result of close observations that measured changes in the planet’s total average brightness as it was eclipsed by its largest moon, Charon. Computer processing yielded brightness maps, which were very basic by modern standards.

In the early 2000s, images taken by the Hubble Space Telescope were processed in order to create a more comprehensive view. Though the images were rather undetailed, they offered a much higher resolution view than the previous maps, allowing certain features – like Pluto’s large bright spots and the dwarf planet’s polar regions – to be resolved for the first time.

However, with the arrival of the New Horizons mission, human beings have been finally treated to a close-up view of Pluto and its surface.  This included Pluto’s now-famous heart-shaped plains, which were captured by the probe’s Long Range Reconnaissance Imager (LORRI) while it was still several days away from making its closest approach.

Our evolving understanding of Pluto, represented by images taken by Hubble in 2002-3 (left), and images taken by New Horizons in 2015 (right). Credit: theguardian.com
Our changing impression of Pluto, represented by images taken by Hubble in 2002-3 (left), and images taken by the New Horizons mission in 2015 (right). Credit: theguardian.com

This was then followed-up by very clear images of its surface features and atmosphere, which revealed floating ice hills, mountains and icy flow plains, and surface clouds composed of methane and tholins. From all of these images, we now know what the surface of this distant world looks like with precision. All of this has allowed scientists here at Earth to reconstruct, in stunning detail, what it would be like to travel to Pluto and stand on its surface.

Amazingly, only half of New Horizon’s images and measurements have been processed so far. And with fresh data expected to arrive until this coming October, we can expect that scientists will be working hard for many years to analyze it all. One can only imagine what else they will learn about this mysterious world. And one can only hope that any news findings will be uploaded to the app (and those like it)!

The VR app can be downloaded at the New York Times VR website, and is available for both Android and Apple devices. It can also be viewed using headset’s like Google Cardboard, a smartphone, and a modified version exists for computer browsers.

Thanks, Comet Pluto. Solar System Nomenclature Needs A Major Rethink

New Horizon's July 2015 flyby of Pluto captured this iconic image of the heart-shaped region called Tombaugh Regio. Credit: NASA/JHUAPL/SwRI.

Pluto can’t seem to catch a break lately. After being reclassified in 2006 by the International Astronomical Union, it seemed that what had been the 9th planet of the Solar System was now relegated to the status of “dwarf planet” with the likes of Ceres, Eris, Haumea, and Makemake. Then came the recent announcements that the title of “Planet 9” may belong to an object ten times the mass of Earth located 700 AU from our Sun.

And now, new research has been produced that indicates that Pluto may need to be reclassified again. Using data provided by the New Horizons mission, researchers have shown that Pluto’s interaction with the Sun’s solar wind is unlike anything observed in the Solar System thus far. As a result, it would seem that the debate over how to classify Pluto, and indeed all astronomical bodies, is not yet over.

Continue reading “Thanks, Comet Pluto. Solar System Nomenclature Needs A Major Rethink”

Scientists Assemble Fresh Global Map of Pluto Comprising Sharpest Flyby Images

NASA’s New Horizons mission science team has produced this updated panchromatic (black-and-white) global map of Pluto. Credits: NASA/JHUAPL/SWRI
NASA’s New Horizons mission science team has produced this updated panchromatic (black-and-white) global map of Pluto. The map includes all resolved images of Pluto’s surface acquired at pixel resolutions ranging from 18 miles (30 kilometers) on the Charon-facing hemisphere (left and right edges of the map) to 770 feet (235 meters) on the hemisphere facing New Horizons during the closest approach on July 14, 2015 (map center).  Credits: NASA/JHUAPL/SWRI
NASA’s New Horizons mission science team has produced this updated panchromatic (black-and-white) global map of Pluto. Credits: NASA/JHUAPL/SWRI

The science team leading NASA’s New Horizons mission that unveiled the true nature of Pluto’s long hidden looks during the history making maiden close encounter last July, have published a fresh global map that offers the sharpest and most spectacular glimpse yet of the mysterious, icy world.

The newly updated global Pluto map is comprised of all the highest resolution images transmitted back to Earth thus far and provides the best perspective to date.

Click on the lead image above to enjoy Pluto revealed at its finest thus far. Click on this link to view the highest resolution version.

Prior to the our first ever flyby of the Pluto planetary system barely 8 months ago, the planet was nothing more than a fuzzy blob with very little in the way of identifiable surface features – even in the most powerful telescopic views lovingly obtained from the Hubble Space Telescope (HST).

Dead center in the new map is the mesmerizing heart shaped region informally known as Tombaugh Regio, unveiled in all its glory and dominating the diminutive world.

The panchromatic (black-and-white) global map of Pluto published by the team includes the latest images received as of less than one week ago on April 25.

The images were captured by New Horizons’ high resolution Long Range Reconnaissance Imager (LORRI).

The science team is working on assembling an updated color map.

During its closest approach at approximately 7:49 a.m. EDT (11:49 UTC) on July 14, 2015, the New Horizons spacecraft 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, the largest moon.

The map includes all resolved images of Pluto’s surface acquired in the final week of the approach period ahead of the flyby starting on July 7, and continuing through to the day of closest approach on July 14, 2015 – and transmitted back so far.

The pixel resolutions are easily seen to vary widely across the map as you scan the global map from left to right – depending on which Plutonian hemisphere was closest to the spacecraft during the period of close flyby.
They range from the highest resolution of 770 feet (235 meters), at center, to 18 miles (30 kilometers) at the far left and right edges.

The Charon-facing hemisphere (left and right edges of the map) had a pixel resolution of 18 miles (30 kilometers).

“This non-encounter hemisphere was seen from much greater range and is, therefore, in far less detail,” noted the team.

However the hemisphere facing New Horizons during the spacecraft’s closest approach on July 14, 2015 (map center) had a far higher pixel resolution reaching to 770 feet (235 meters).

Coincidentally and fortuitously the spectacularly diverse terrain of Tombaugh Regio and the Sputnik Planum area of the hearts left ventricle with ice flows and volcanoes, mountains and river channels was in the region facing the camera and sports the highest resolution imagery.

See below a newly released shaded relief map of Sputnik Planum.

This new shaded relief view of the region surrounding the left side of Pluto’s heart-shaped feature – informally named Sputnik Planum – shows that the vast expanse of the icy surface is on average 2 miles (3 kilometers) lower than the surrounding terrain.  Angular blocks of water ice are “floating” in the bright deposits of softer, denser solid nitrogen.   Credits:  NASA/JHUAPL/SwRI
This new shaded relief view of the region surrounding the left side of Pluto’s heart-shaped feature – informally named Sputnik Planum – shows that the vast expanse of the icy surface is on average 2 miles (3 kilometers) lower than the surrounding terrain. Angular blocks of water ice are “floating” in the bright deposits of softer, denser solid nitrogen. Credits: NASA/JHUAPL/SwRI

“Sputnik Planum – shows that the vast expanse of the icy surface is on average 2 miles (3 kilometers) lower than the surrounding terrain. Angular blocks of water ice along the western edge of Sputnik Planum can be seen “floating” in the bright deposits of softer, denser solid nitrogen,” according to the team.

Even more stunning images and groundbreaking data will continue streaming back from New Horizons until early fall, across over 3 billion miles of interplanetary space.

Thus the global map of Pluto will be periodically updated.

Its taking over a year to receive the full complement of some 50 gigabits of data due to the limited bandwidth available from the transmitter on the piano-shaped probe as it hurtled past Pluto, its largest moon Charon and four smaller moons.

Pluto is the last planet in our solar system to be visited in the initial reconnaissance of planets by spacecraft from Earth since the dawn of the Space Age.

This new global mosaic view of Pluto was created from the latest high-resolution images to be downlinked from NASA’s New Horizons spacecraft and released on Sept. 11, 2015. The images were taken as New Horizons flew past Pluto on July 14, 2015, from a distance of 50,000 miles (80,000 kilometers). This new mosaic was stitched from over two dozen raw images captured by the LORRI imager and colorized. Annotated with informal place names. Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Marco Di Lorenzo/Ken Kremer/kenkremer.com
This new global mosaic view of Pluto was created from the latest high-resolution images to be downlinked from NASA’s New Horizons spacecraft and released on Sept. 11, 2015. The images were taken as New Horizons flew past Pluto on July 14, 2015, from a distance of 50,000 miles (80,000 kilometers). This new mosaic was stitched from over two dozen raw images captured by the LORRI imager and colorized. Annotated with informal place names. Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Marco Di Lorenzo/Ken Kremer/kenkremer.com

New Horizons remains on target to fly by a second Kuiper Belt Object (KBO) on Jan. 1, 2019 – tentatively named PT1, for Potential Target 1. It is much smaller than Pluto and was recently selected based on images taken by NASA’s Hubble Space Telescope.

Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.

Ken Kremer

Gravity Waves On Pluto?

The varying brightness in Pluto's atmosphere is caused by atmospheric gravity waves, or buoyancy waves. Image: NASA/New Horizons/Johns Hopkins APL/SWRI
The varying brightness in Pluto's atmosphere is caused by atmospheric gravity waves, or buoyancy waves. Image: NASA/New Horizons/Johns Hopkins APL/SWRI

New Horizons’ historic journey to Pluto and beyond continues to provide surprises. As data from the spacecraft’s close encounter with Pluto and its moons arrives at Earth, scientists are piecing together an increasingly intriguing picture of the dwarf planet. The latest discovery is centred around Pluto’s atmosphere, and what are called ‘atmospheric gravity waves.’

Atmospheric gravity waves are a different phenomenon than the gravity waves that were detected for the first time in February, 2016. Those gravity waves are ripples in the fabric of space time, first predicted by Albert Einstein back in 1916. After years of searching, the LIGO instrument detected gravity waves that resulted from two black holes colliding. The discovery of what you might call ‘Einsteinian Gravity Waves’ may end up revolutionizing astronomy.

New Horizons has revealed surprise after surprise in its study of Pluto. Its atmosphere has turned out to be much more complex than anybody expected. It’s composed of 90% nitrogen, with extensive haze layers. Scientists have discovered that Pluto’s atmosphere can vary in brightness depending on viewpoint and illumination, while the vertical structure of the layered haze remains unchanged.

Scientists studying the New Horizons’ data think that atmospheric gravity waves, also called buoyancy waves, are responsible. Atmospheric gravity waves are known to exist on only two other planets; Earth and Mars. They are typically caused by wind flowing over obstructions like mountain ranges.

The layers in Pluto’s atmosphere, and their varying brightness, are most easily seen when they are backlit by the Sun. This was the viewpoint New Horizons had when it captured these images on its departure from Pluto on July 14, 2015. The spacecraft’s Long Range Reconnaissance Imager (LORRI) captured them, using time intervals of 2 to 5 hours. What they show is the brightness of the layers changing by 30% without any change in their height above the surface of the planet.

LORRI, as its name suggests, is a long range image capture instrument. It also captures high resolution geologic data, and was used to map Pluto’s far side. The principal investigator for LORRI is Andy Cheng, from the Applied Physics Laboratory at Johns Hopkins University, in Maryland. “Pluto is simply amazing,” said Andy Cheng. “When I first saw these images and the haze structures that they reveal, I knew we had a new clue to the nature of Pluto’s hazes. The fact that we don’t see the haze layers moving up or down will be important to future modelling efforts.”

Overall, Pluto and its system of moons has turned out to be a much more dynamic place than previously thought. A geologically active landscape, possible ice volcanoes, eroding cliffs made of methane ice, and more, have woken us up to Pluto’s complexity. But its atmosphere has turned out to be just as complex and puzzling.

New Horizons has departed the Pluto system now, and is headed for the Kuiper Belt. The Kuiper Belt is considered a relic of the early Solar System. New Horizons will visit another icy world there, and hopefully continue on to the edge of the heliosphere, the same way the Voyage probes have. New Horizons has enough energy to last until approximately the mid-2030’s, if all goes well.