Nancy has been with Universe Today since 2004, and has published over 6,000 articles on space exploration, astronomy, science and technology. She is the author of two books: "Eight Years to the Moon: the History of the Apollo Missions," (2019) which shares the stories of 60 engineers and scientists who worked behind the scenes to make landing on the Moon possible; and "Incredible Stories from Space: A Behind-the-Scenes Look at the Missions Changing Our View of the Cosmos" (2016) tells the stories of those who work on NASA's robotic missions to explore the Solar System and beyond.
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This new mosaic of Pluto is from the latest high-resolution images sent to Earth from the New Horizons spacecraft shows what you would see if you were approximately 1,100 miles (1,800 kilometers) above Pluto’s equatorial area, looking northeast over the dark, cratered, informally named Cthulhu Regio toward the bright, smooth, expanse of icy plains informally called Sputnik Planum. The entire expanse of terrain seen in this image is 1,100 miles (1,800 kilometers) across. The images were taken as New Horizons flew past Pluto on July 14, 2015, from a distance of 50,000 miles (80,000 kilometers). Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
New Horizons scientists say they are “reeling” from the new images sent back from the spacecraft which were released today. The new data set shows an amazing range of complex features on Pluto’s surface and in its atmosphere.
New images show there might even be a field of dark wind-blown dunes, among other possibilities.
“Seeing dunes on Pluto — if that is what they are — would be completely wild, because Pluto’s atmosphere today is so thin,” said William B. McKinnon, a GGI deputy lead from Washington University, St. Louis. “Either Pluto had a thicker atmosphere in the past, or some process we haven’t figured out is at work. It’s a head-scratcher.”
Plus, a new view of Pluto’s hazy backlit atmosphere shows what are likely crepuscular rays — shadows cast on the haze by topography such as mountain ranges on Pluto, similar to the rays sometimes seen in the sky after the sun sets behind mountains on Earth.
Two different versions of an image of Pluto’s haze layers, taken by New Horizons as it looked back at Pluto’s dark side nearly 16 hours after close approach, from a distance of 480,000 miles (770,000 kilometers). The left version has had only minor processing, while the right version has been specially processed to reveal a large number of discrete haze layers in the atmosphere. Subtle parallel streaks in the haze may be crepuscular rays- shadows cast on the haze by topography such as mountain ranges on Pluto, similar to the rays sometimes seen in the sky after the sun sets behind mountains on Earth.Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.
Scientists say these new images reveal that Pluto’s global atmospheric haze has many more layers than scientists realized, and that the haze actually creates a twilight effect that softly illuminates nightside terrain near sunset, making them visible to the cameras aboard New Horizons.
“This bonus twilight view is a wonderful gift that Pluto has handed to us,” said John Spencer, a GGI deputy lead from SwRI. “Now we can study geology in terrain that we never expected to see.”
This image of Pluto from NASA’s New Horizons spacecraft, processed in two different ways, shows how Pluto’s bright, high-altitude atmospheric haze produces a twilight that softly illuminates the surface before sunrise and after sunset, allowing the sensitive cameras on New Horizons to see details in nighttime regions that would otherwise be invisible. The right-hand version of the image has been greatly brightened to bring out faint details of rugged haze-lit topography beyond Pluto’s terminator, which is the line separating day and night. The image was taken as New Horizons flew past Pluto on July 14, 2015, from a distance of 50,000 miles (80,000 kilometers). Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
These new images are the first to be sent from the spacecraft since shortly after it flew past the Pluto system in July of this year. This is the beginning of an “intensive” downlink session that will last for a year or more, sending back the 50 gigabits or so of data the spacecraft collected and stored on its digital recorders during the flyby. These new images are “selected high priority” data-sets that the science team has been anxiously waiting for.
The new images are “lossless” — meaning the data sent back from the New Horizon spacecraft is using a type of data compression algorithms that allows the original data to be perfectly reconstructed from the compressed data. Planetary astronomer Alex Parker said on Twitter that this means the even views we’ve seen in the previous Pluto images from New Horizons are much sharper and crisper.
Here are more:
A close-up of a dark area on the edge of the heart-shaped light region on Pluto. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
Besides the dunes and new atmospheric imagery, other views show nitrogen ice flows that apparently oozed out of mountainous regions onto plains, and even networks of valleys that may have been carved by material flowing over Pluto’s surface. They also show large regions that display chaotically jumbled mountains, which reminded many of the terrain on Jupiter’s icy moon Europa.
“The surface of Pluto is every bit as complex as that of Mars,” said Jeff Moore, leader of the New Horizons Geology, Geophysics and Imaging (GGI) team at NASA’s Ames Research Center. “The randomly jumbled mountains might be huge blocks of hard water ice floating within a vast, denser, softer deposit of frozen nitrogen within the region informally named Sputnik Planum.”
In the center of this 300-mile (470-kilometer) wide image of Pluto from NASA’s New Horizons spacecraft is a large region of jumbled, broken terrain on the northwestern edge of the vast, icy plain informally called Sputnik Planum, to the right. The smallest visible features are 0.5 miles (0.8 kilometers) in size. This image was taken as New Horizons flew past Pluto on July 14, 2015, from a distance of 50,000 miles (80,000 kilometers). Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
This image of Pluto’s largest moon Charon, taken by NASA’s New Horizons spacecraft 10 hours before its closest approach to Pluto on July 14, 2015 from a distance of 290,000 miles (470,000 kilometers), is a recently downlinked, much higher quality version of a Charon image released on July 15. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.
The New Horizons spacecraft is now about 5 billion kilometers (more than 3 billion miles) from Earth, and more than 69 million kilometers (43 million miles) beyond Pluto. The team says the spacecraft is healthy and all systems are operating normally.
You can see all the latest imagery sent back from New Horizons at this website. New images will be added every week, according to the New Horizons staff, likely on Fridays.
Details of Pluto’s largest moon, Charon, are revealed in this image from New Horizons’ Long Range Reconnaissance Imager (LORRI), taken July 13, 2015, from a distance of 289,000 miles (466,000 kilometers), combined with color information obtained by New Horizons’ Ralph instrument on the same day. The distinctive red marking in Charon’s north polar region is currently being studied by scientists. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)
As we await new imagery and data from the New Horizons’ flyby of the Pluto system to be transmitted to Earth, one piece of the Pluto-Charon puzzle that scientists are looking forward learning more about is the mysterious “dark pole” on Charon. Images sent immediately after the flyby reveal Charon’s north polar region is much darker than the lighter-colored material surrounding it, and it actually has a reddish cast to it.
The New Horizons team says the red pole appears to be a thin deposit of dark material over a distinct, sharply bounded, angular feature – perhaps and impact basin – and scientists hope to learn more by studying higher-resolution images that are currently being beamed back to Earth from the spacecraft.
Carly Howett, a senior research scientist at the Southwest Research Institute, is one of the scientists studying the mystery of what is causing this color difference and why it shows up at Charon’s north pole.
“Looking at Charon, it’s very clear that the northern polar region is much redder than the rest of the moon,” said Howett in a post on the New Horizons website. “Surfaces vary in color when something about them changes.”
So what is this red material? The leading theory right now is that material from Pluto’s atmosphere is falling to Charon and being ensnared in the polar region by what is known as “cold-trapping.”
It’s is so cold at Charon’s poles – temperatures there vary are just a tad warmer than absolute zero, between -433 and -351 °F (-258 and -213 °C) – that any gases settling there would freeze solid instead of escaping. And with the combination of extremely cold temperatures and solar radiation, the material is transformed to a new substance, and is being trapped on the pole. Howett said it likely won’t disappear with any seasonal changes on Charon.
“We know Pluto’s atmosphere is mainly nitrogen, with some methane and carbon monoxide,” she said, “so we expect that these same constituents are slowly coating Charon’s winter pole. The frozen ices would sublimate away again as soon as Charon’s winter pole emerges back into sunlight, except for one important detail: solar radiation modifies these ices to produce a new substance, which has a higher sublimation temperature and can’t sublimate and then escape from Charon.”
What is the new substance? Scientists can’t say for sure yet, but it might be a tholin.
Scientists at Johns Hopkins University’s Hörst Laboratory have produced complex chemical compounds called tholins, which may give Pluto its reddish hue. (Image credit: Chao He, Xinting Yu, Sydney Riemer, and Sarah Hörst, Johns Hopkins University).
What is a tholin? Tholins were first created in a laboratory by in the 1970s by Carl Sagan and his team at Cornell. According to planetary scientist Sarah Hörst, who wrote about tholins on The Planetary Society website, Sagan and his team would take mixtures of cosmically relevant gases and irradiate them with various energy sources. The result was “a brown, sometimes sticky, residue,” as Sagan described them in a paper he wrote in 1979.
Hörst said Sagan and team “were searching for answers to questions ranging from ‘why is the Great Red Spot red’ to ‘how did life on Earth originate’ and in the process produced material for which there was no name.”
They came up with the name “tholin,” and theorized that tholins could be a constituent of the Earth’s primitive oceans and therefore as relevant to the origin of life.
In the article Hörst wrote, “I have been studying tholin for almost a decade and in my experience the most frequently used synonyms for tholin are “gunk”, “brown gunk”, and “complex organic gunk”. Tholin is also often described as a “tar-like” substance. Words like tar, kerogen, bitumen, petroleum, asphalt, etc. all describe substances that are potentially similar to tholin in some ways. However, these materials all result from life; they are’biotic.’”
Charon approach from New Horizons. Credit: NASA/Damian Peach
Finding out more about what is going on at Charon’s north pole is indeed intriguing. Tholins might be the same material that give Pluto its reddish-brown hue in some regions, too.
Howett told Universe Today that the main instrument on New Horizons that will really pin down the compositional information is LEISA (Linear Etalon Imaging Spectral Array).
“This instrument observes 250 wavelengths between 1.25-2.5 microns, making it ideal for detecting the spectral signature of solid features,” she said via email. “We don’t know exactly the composition of the tholin on Charon (many different types are possible) but with LEISA we can look for differences in the spectra between the Charon’s anomalous red region and those surrounding it – to give us some hints of the change in surface composition and the “raw ingredients” for the tholin.”
For example, Howett said, maybe they’ll see more hydrogen cyanide (HCN) around the north pole region, which would open up a lot of complex chemistry options.
“We will start getting this data down in the next few weeks, so hopefully we’ll have some answers soon!” she said.
Artist's depiction of the asteroid belt between Mars and Jupiter. Credit: David Minton and Renu Malhotra
4.6 billion years ago, our Solar System formed from a collection of gas and dust surrounding our nascent Sun. While much of the gas and dust in this protoplanetary disk coalesced to form the planets, some of the debris was left over.
Some of debris was shattered remnants of planetesimals – bodies within the young Sun’s solar nebula that never grew large enough to become planets, and scientists theorize that large collisions in the early, chaotic Solar System pulverized these planetesimals into smaller pieces. Other debris never came together due to the massive gravitational pull from Jupiter.
These rocky remnants are now the asteroids that travel about our Solar System. Since these “leftovers” contain clues about the early days of our Solar System, scientists are eager to study them.
Definition of an Asteroid
Asteroids are rocky, metallic bodies that orbit the Sun. They are made from different kinds of rock and metals, with the metals being mostly nickel and iron. They are sometimes called “minor planets” but they are much, much smaller than the planets or moons. They don’t have atmospheres, but about 150 asteroids are known to have small “moons” orbiting them, and some even have two moons. There are also binary (double) asteroids, where two rocky bodies of roughly equal size orbit each other, as well as triple asteroid systems.
At least one asteroid has rings. This surprise discovery was made in 2013 when scientist watched Asteroid Chariklo pass in front of a star. The asteroid made the background star “blink” several times, which led to the discovery that two rings are surrounding the asteroid.
The asteroids of the inner Solar System and Jupiter: The donut-shaped asteroid belt is located between the orbits of Jupiter and Mars. Credit: Wikipedia Commons
Location
The majority of known asteroids are in the asteroid belt, a large donut-shaped ring located between the orbits of Mars and Jupiter, and orbit approximately 2 to 4 AU (186 million to 370 million miles/300 million to 600 million kilometers) from the Sun. (*Note: 1 AU, or Astronomical Unit, equals the distance from the Earth to the Sun.)
Sometimes, the orbits of some asteroids get perturbed or altered from gravitational interactions with planets or other asteroids and they end up coming closer to the Sun, and therefore closer to Earth. These asteroids are known as Near Earth Asteroids, and are classified as NEAs if their orbits bring them within 1.3 AU (121 million miles/195 million kilometers) of the Earth.
Asteroids that actually cross Earth’s orbital path are known as Earth-crossers and, an asteroid is called a Potentially Hazardous Asteroid (PHA) if it will come less than .05 AU from Earth.
In addition to the asteroid belt, however, there have been recent discussions among astronomers about the potential existence of large number asteroids in the far reaches of our Solar System in the Kuiper Belt and Oort Cloud.
Number of Asteroids
There are millions of asteroids in our Solar System. Some scientists estimate the asteroid belt has between 1.1 and 1.9 million asteroids larger than 1 kilometer (0.6 mile) in diameter, and millions of smaller ones. Most of the undiscovered asteroids are likely the smaller ones (less than 100 km across) which are more difficult to detect. Other astronomers estimate there are over 150 million asteroids in the entire Solar System. New asteroids are being discovered all the time.
On average, three new NEAs are found every day. As of September 06, 2015, 13,024 Near-Earth objects have been discovered. About 875 of these NEOs are asteroids with a diameter of approximately 1 kilometer or larger. Also, 1,609 of these NEOs have been classified as Potentially Hazardous Asteroids (PHAs), but none at this time are expected to impact Earth. Check the NASA NEO website for updates.
Contrary to popular imagery that might be seen in science fiction movies and imagery, the asteroid belt is mostly empty. According to NASA, the average distance between objects in the asteroid belt is greater than 1-3 million km. The asteroids are spread over such a large volume that you likely would not run into an asteroid if you sent a spacecraft through the asteroid belt. Even though there may be millions of asteroids in the asteroid belt, most are small. Astronomers say if you put all of them together, the combination would be smaller than our moon.
Asteroids are not easy to spot because they often are made from dark material, and are difficult to find against the darkness of outer space. There are several dedicated surveys using both Earth-based telescopes and spacecraft searching the skies for asteroids. They include:
Catalina Sky Survey
Pan-STARRS
LINEAR
Spacewatch
NEOWISE
You can find more information about NASA’s NEO Search Program here.
Ceres compared to asteroids visited to date, including Vesta, Dawn’s mapping target in 2011. Image by NASA/ESA/JAXA. Compiled by Paul Schenck.
Shape and Size
Most asteroids are irregularly shaped, though some are nearly spherical, and they are often pitted or cratered from impacts with other asteroids. As they revolve around the Sun in elliptical orbits, the asteroids also rotate, and have some quite erratic movements, and literally tumble through space.
The size of what classifies as an asteroid is not extremely well defined, as an asteroid can range from a pebbles, to a few meters wide – like a boulder — to objects that are hundreds of kilometers in diameter. The largest asteroid is asteroid Ceres at about 952 km (592 miles) in diameter, and Ceres is so large that it is also categorized as a dwarf planet. Over 200 asteroids are known to be larger than 100 km (60 miles), with sixteen asteroids known to have diameters of 240 kilometers (150 miles) or greater.
Asteroids we’ve seen up close show various shapes. Credit: NASA
The following animation is based on a 2008 a study of the size distribution of asteroid families using data from the Sloan Digital Sky Survey and was created by Alex Parker.
Composition
Most asteroids are made of rock — with some composed of clay and silicate — and different metals, mostly nickel and iron. Other precious metals have been found on some asteroids, including platinum and gold. A wide variety of minerals have also been found on various asteroids including olivine and pyroxene, which are also found on meteorites that have landed on Earth.
Most asteroids contain vast amounts of carbon, which means they closely follow the elemental composition of the Sun. There are indications that asteroids also contain water or ice in their interiors, and observations by the Dawn mission shows indications that water may have flowed across the surface of Vesta.
You can find more details about what asteroids are made of at our article here.
Asteroids are different from comets, which are mostly rock and ice. Comets usually have tails, which are made from ice and debris sublimating as the comet gets close to the Sun. Asteroids typically don’t have tails, even those near the Sun. But recently, astronomers have seen some asteroids that have sprouted tails, such as asteroid P/2010 A2. This seems to happen when the asteroid has been hit or pummeled by other asteroids and dust or gas is ejected from their surfaces, creating a sporadic tail effect. These so-called “active asteroids” are a newly recognized phenomenon, and as of this writing, only 13 known active asteroids have been found in the main asteroid belt, and so they are very rare.
Asteroid classifications
Asteroids have a few different classifications based on their location and make-up.
Location classifications are:
Main Belt Asteroids: (which includes the majority of known asteroids which orbit within the asteroid belt between Mars and Jupiter)
Trojans: These asteroids share an orbit with a larger planet, but do not collide with it because they gather around two special places in the orbit (called the L4 and L5 Lagrangian points). There, the gravitational pull from the sun and the planet are balanced by a trojan’s tendency to otherwise fly out of the orbit. The Jupiter trojans form the most significant population of trojan asteroids. It is thought that they are as numerous as the asteroids in the asteroid belt. There are Mars and Neptune trojans, and NASA announced the discovery of an Earth trojan in 2011.
Near-Earth Asteroids: These objects have orbits that pass close by that of Earth.
Then, there are subgroups of Near-Earth asteroids, and are categorized by their orbits.
Atiras are NEAs whose orbits are contained entirely with the orbit of the Earth, having a distance of less than 1 AU. They are named after asteroid 163693 Atira.
Atens are Earth-crossing NEAs with semi-major axes smaller than Earth’s, with a distance of less than 1 AU. They are named after asteroid 2062 Aten.
Apollos are Earth-crossing NEAs with semi-major axes larger than Earth’s, with a distance of less than 1 AU. They are named after asteroid 1862 Apollo.
Amors are Earth-approaching NEAs with orbits outside of Earth’s but inside of Mars’ orbit. They are named after asteroid 1221 Amor.
Classification by the composition tell us what the asteroid is made of, and this is related to how far from the Sun an asteroid formed. Some experienced high temperatures after they formed and partly melted, with iron sinking to the center and forcing basaltic (volcanic) lava to the surface. Only one such asteroid, Vesta, survives to this day. There are three basic types of asteroids:
C-type (chondrite) asteroids are most common, making up about 75 percent of known asteroids. They are very dark in appearance and probably consist of clay and silicate rocks. They are among the most ancient objects in the solar system. Their composition is thought to be similar to the Sun, but depleted in hydrogen, helium, and other volatiles. C-type asteroids mainly are in the asteroid belt’s outer regions.
S-types (stony) are made up of silicate materials and nickel-iron, and accounts for about 17 percent of known asteroids. They are brighter than C-type and they dominate the inner asteroid belt.
M-types (metallic) are made from nickel and iron and accounts for about 8 percent of known asteroids. They are brighter than C-type and they can be found in the asteroid belt’s middle region.
Asteroid Impacts with Earth
How likely is it that our planet could be hit by a large asteroid or comet? We do know that Earth and the Moon have been struck many times in the past by asteroids whose orbits bring them into the inner Solar System. You can see pictures some of Earth’s largest and most spectacular impact craters here.
Studies of Earth’s history indicate that about once every 5,000 years or so (on average) an object the size of a football field hits Earth and causes significant damage. Once every few million years on average an object large enough to cause regional or global disaster impacts Earth.
Satellite views of the Chicxulub impact site. Image credit: NASA/JPL
There is strong scientific evidence that asteroid impacts played a major role in the mass extinctions documented in Earth’s fossil records. It is widely accepted that an impact 65 million years ago of an asteroid or comet at least 6 miles (10 kilometers) in diameter in the Yucatan peninsula, known as the Chicxulub crater is associated with the extinction of the dinosaurs.
We know of only a handful of recent large asteroid impacts. One is the forest-flattening 1908 Tunguska explosion over Siberia (which may have been the result of a comet) and another is the February 2013 meteor that exploded over Chelyabinsk, breaking windows and injuring many, mostly from broken glass.
But a recent study by the B612 Foundation found that there were 26 explosive airburst events similar to the Chelyabinsk event recorded from 2000 to 2013. The explosions asteroids ranged from one to 600 kilotons in energy output.
NASA says that about once a year, an automobile-sized asteroid hits Earth’s atmosphere, creates an impressive fireball, and burns up before reaching the surface.
NEOs still pose a danger to Earth today, but NASA, ESA and other space agencies have search programs that have discovered hundreds of thousands of main-belt asteroids, comets. None at this time pose any threat to Earth. You can find out more on this topic at NASA’s Near Earth Object Program website.
All asteroids and comets visited by spacecraft as of November 2010 Credits: Montage by Emily Lakdawalla. Ida, Dactyl, Braille, Annefrank, Gaspra, Borrelly: NASA / JPL / Ted Stryk. Steins: ESA / OSIRIS team. Eros: NASA / JHUAPL. Itokawa: ISAS / JAXA / Emily Lakdawalla. Mathilde: NASA / JHUAPL / Ted Stryk. Lutetia: ESA / OSIRIS team / Emily Lakdawalla. Halley: Russian Academy of Sciences / Ted Stryk. Tempel 1, Hartley 2: NASA / JPL / UMD. Wild 2: NASA / JPL.
History
We’ve gained knowledge of asteroids from three main sources: Earth-based remote sensing, data from spacecraft and laboratory analysis of meteorites.
Here are some important dates in the history of our knowledge and study of asteroids, including spacecraft missions that flew by or landed on asteroids:
1801: Giuseppe Piazzi discovers the first and largest asteroid, Ceres, orbiting between Mars and Jupiter. 1898: Gustav Witt discovers Eros, one of the largest near-Earth asteroids. 1991-1994: The Galileo spacecraft takes the first close-up images of an asteroid (Gaspra) and discovers the first moon (later named Dactyl) orbiting an asteroid (Ida). 1997-2000: The NEAR Shoemaker spacecraft flies by Mathilde and orbits and lands on Eros. 1998: NASA establishes the Near Earth Object Program Office to detect, track and characterize potentially hazardous asteroids and comets that could approach Earth. 2006: Japan’s Hayabusa becomes the first spacecraft to land on, collect samples and take off from an asteroid. 2006: Ceres attains a new classification — dwarf planet — but retains its distinction as the largest known asteroid. 2007: The Dawn spacecraft is launched on its journey to the asteroid belt to study Vesta and Ceres. 2008: The European spacecraft Rosetta, on its way to study a comet in 2014, flies by and photographs asteroid Steins, a type of asteroid composed of silicates and basalts. 2010: Japan’s Hayabusa returns its asteroid sample to Earth. 2010: Rosetta flies by asteroid Lutetia, revealing a primitive survivor from the violent birth of our solar system. 2011-2015: Dawn studies Vesta, becoming the first spacecraft to orbit a main-belt asteroid. It now is studying the dwarf planet Ceres, located in the main asteroid belt.
Below is a list of links to articles about asteroids in general, asteroid related events in history, and some specific asteroids. Many hours of research are waiting for you. Enjoy!
Backlit by the sun, Pluto’s atmosphere rings its silhouette like a luminous halo in this image taken by NASA’s New Horizons spacecraft around midnight EDT on July 15. This global portrait of the atmosphere was captured when the spacecraft was about 1.25 million miles (2 million kilometers) from Pluto and shows structures as small as 12 miles across. The image, delivered to Earth on July 23, is displayed with north at the top of the frame. Credits: NASA/JHUAPL/SwRI
If you thought the New Horizons spacecraft flyby of the Pluto system happened waaaay too fast and you’re pining for more images and data, you are in luck. What the spacecraft has been able to send back so far is just the tip of the icy dwarf planet, so to speak.
Starting tomorrow, Saturday, September 5, 2015, the spacecraft will begin an “intensive” downlink session that will last for a year or more, sending back the tens of gigabits of data the spacecraft collected and stored on its digital recorders during the flyby. What will come first are “selected high priority” data-sets that the science team has been anxiously waiting for.
“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,” said New Horizons Principal Investigator Alan Stern. “And what’s coming is not just the remaining 95 percent of the data that’s still aboard the spacecraft – it’s the best datasets, the highest-resolution images and spectra, the most important atmospheric datasets, and more. It’s a treasure trove.”
Plus, every Friday from here on out, you can count on getting new, unprocessed pictures from the Long Range Reconnaissance Imager (LORRI) on the New Horizons project website. Here’s where you can find the images, and the next LORRI set is scheduled for posting on Sept. 11, so set your calendars.
It’s been 7 weeks since New Horions’ historic flyby of the Pluto system, and during this quick pass, the spacecraft was designed “to gather as much information as it could, as quickly as it could, as it sped past Pluto and its family of moons – then store its wealth of data to its digital recorders for later transmission to Earth,” said the mission team.
A portrait from the final approach. Pluto and Charon display striking color and brightness contrast in this composite image from July 11, showing high-resolution black-and-white LORRI images colorized with Ralph data collected from the last rotation of Pluto. Color data being returned by the spacecraft now will update these images, bringing color contrast into sharper focus. Credits: NASA-JHUAPL-SWRI
Why is it taking so long? The spacecraft runs on between 2-10 watts of power, and it had to prioritize on data collection during the flyby. The data has been stored on two onboard, solid-state, 8 gigabyte memory banks. The spacecraft’s main processor compresses, reformats, sorts and stored the data on a recorder, similar to a flash memory card for a digital camera.
One issue is the time it takes to get data from New Horizons as it speeds even farther away from Earth, past the Pluto system. Even moving at light speed, the radio signals from New Horizons containing data need more than 4 ½ hours to cover the 4 billion km (3 billion miles) to reach Earth.
But the biggest issue is the relatively low “downlink” rate at which data can be transmitted to Earth, especially when you compare it to rates now common for high-speed Internet surfers.
All communications with New Horizons – from sending commands to the spacecraft, to downlinking all of the science data from the historic Pluto encounter – happen through NASA’s Deep Space Network of antenna stations in (clockwise, from top left) Madrid, Spain; Goldstone, California, U.S.; and Canberra, Australia. Even traveling at the speed of light, radio signals from New Horizons need more than 4 ½ hours to travel the 3 billion miles between the spacecraft and Earth. Credit: NASA.
During the Jupiter flyby in February 2007, New Horizons data return rate was about 38 kilobits per second (kbps), which is slightly slower than the transmission speed for most computer modems. Now, after the flyby, the average downlink rate is going to be approximately 1-4 kilobits per second, depending on how the data is sent and which Deep Space Network antenna is receiving it. Sometimes, when possible, the spacecraft will be able to increase the rate by downlinking with both of its transmitters through NASA’s largest antennas of the DSN. But even then, it will take until late 2016 to send Pluto flyby data stored on the spacecraft’s recorders.
Patience you must have, my young padawan.
“The New Horizons mission has required patience for many years, but from the small amount of data we saw around the Pluto flyby, we know the results to come will be well worth the wait,” said Hal Weaver, New Horizons project scientist.
The data received by the DSN (you can watch the live data link happen on the Eyes of the Solar System DSN NOW page) will be sent to the New Horizons Mission Operations Center at the Applied Physics Lab a Johns Hopkins University, where data will be “unpacked” and stored. Then mission operations and instrument teams will scour the engineering data for performance trend information, while science data will be copied to the Science Operations Center at the Southwest Research Institute in Boulder, Colorado.
At the Science Ops Center, data will pass through “pipeline” software that converts the data from instrumental units to scientific units, based on calibration data obtained for each instrument. Both the raw and calibrated data files will be formatted for New Horizons science team members to analyze. Both the raw and calibrated data, along with various ancillary files (such as documents describing the pipeline process or the science instruments) will be archived at the Small Bodies Node of NASA’s Planetary Data System.
An air traffic control map from a 2014 FAA report. Credit: FAA.
According to a recent report by the US Federal Aviation Administration (FAA), airports across the country are seeing record passenger numbers. Along with that comes congestion at airport terminals and runways, causing delays and other problems — including accidents. The FAA report said if nothing is done to curb congestion by 2030, the busiest US airports will see problems rise dramatically. While infrastructure such as terminals and runways can be expanded or enhanced there’s one piece of the airport real estate that can’t be expanded: airspace.
As airspace becomes increasingly crowded with additional planes, and with the upsurge in vehicles like drones and other various aircraft, experts from the aerospace division at NASA say our current air traffic control system is not equipped to handle the predicted volume or variety of aircraft predicted for 2035 and beyond.
The ‘Sky For All’ challenge logo. Credit: HeroX.
To overcome this challenge and ensure safe access for all commuters, HeroX and the Ab Initio Design element of the NASA Safe Autonomous Operations Systems (SASO) Project is asking for help in designing an airspace system that allows vehicles to safely and efficiently navigate dense and diverse future airspace.
“NASA is reaching out to the problem-solving community, asking innovators to cast aside the restraints of current transportation models and develop a clean-slate, revolutionary design and concept of operations for the airspace of the future,” says a new challenge called “Sky For All” posted on the HeroX website.
HeroX is an organization that uses incentive prize challenges as a way to spur innovations to solve problems. Prizes for this “Sky for All” challenge will be have a total prize of $15,000, with First Place receiving $10,000, Second Place $3,000 and Third Place $2,000.
The problem is that experts estimate that twenty years from now, 10 million manned and unmanned vehicles may traverse the U.S. airspace every day, up from the current 50,000 operations per day.
“The U.S. airspace system evolved over time in response to accidents and changing technology,” says the HeroX challenge page. “Current operations support approximately and boast the highest safety record of any mode of transportation, but this system has approached saturation and will not scale to accommodate future needs. Our goal is to build an airspace system that scales to 10 million vehicles per day (including personal air vehicles, passenger jets, unmanned vehicles of various sizes and speeds, stationary objects, space vehicles, etc.) by the year 2035.”
To achieve this, a “breakthrough” in airspace system design and concept of operations is needed as new vehicles — such as drones of various sizes operating at different altitudes, commercial space launches, wind turbines in jet streams — are already being introduced into the airspace.
“We want airspace that can scale to full capacity under normal conditions and scale back to equally safe, reduced capacity under degraded conditions,” says HeroX.
Innovators are asked to use a “clean-slate” approach of coming up with completely new designs and concepts of operations, and include ways to deal with issues such as protection from cyber-attacks and an ever-changing global environment.
This challenge is currently open to pre-registration and final guidelines will be posted when the challenge officially launches on September 22, 2015.
Stunning downrange plume over the rising sun, about 3 mins after launch of the MUOS-4 satellite from Space Launch Complex 41 in Florida. Used by permission. Credit and copyright: Mike Seeley.
Skywatchers across Central Florida got an unusual view early Wednesday morning in conjunction with the Atlas V launch of the MUOS-4 satellite.
“That wasn’t thunder this AM, Florida: An absolutely stunning MUOS launch!” tweeted photographer Michael Seeley, who shared several images of the launch with Universe Today. Mike is a freelance photographer and works with Spaceflight Insider. You can see more of his imagery at his website.
The pre-dawn light combined with unusual atmospheric conditions produced stunning views both during and well after the launch. The skyshow was visible across a wide area.
“Folks as far south as Miami and up to Jacksonville to the north saw it,” Universe Today’s David Dickinson said. “I even heard kids waiting for the school bus on our street crying out in surprise!”
You can read more about the launch and the mission in our article from Ken Kremer, but see a stunning gallery of images of the unusual cloud formations following the launch below:
A long exposure image of the light trail from the Atlas V launch of the MUOS-4 satellite, as seen from the ITL Causeway. Image used by permission. Credit and copyright: Michael Seeley.A closeup view of the Atlas V MUOS-4 launch by United Launch Alliance. Image used by permission. Credit and copyright: Michael Seeley.
Below are a group of images and video from UT’s David Dickinson, taken about 100 miles away from Cape Canaveral in Hudson, Florida:
The launch of the MUOS-4 satellite from Cape Canaveral, Florida on September 2, 2015 created an unusual noctilucent cloud display, visible even from 100 miles away. Credit and copyright: David Dickinson.Remaining noctilucent clouds about 25 minutes after the launch of the MUOS-4 satellite on board an Atlas V rocket on September 2, 2015. Image taken from Hudson, Florida, about 100 miles west of Cape Canaveral. Credit and copyright: David Dickinson.A view from Hudson, Florida, about 100 miles west of Cape Canaveral after the launch of the MUOS-4 Satellite on September 2, 2015. Credit and copyright: David Dickinson.An Atlas V rocket carrying the MUOS-4 mission lifts off from Space Launch Complex 41, creating a unique light display. Sept. 2, 2015. Credit: ULA.
A montage of 31 images taken in less than a second as the International Space Station transits the Sun and a solar prominence. Credit and copyright: Thierry Legault.
When you’re Thierry Legault and you want to challenge yourself, the bar is set pretty high.
“This is a challenge I imagined some time ago,” Legault told Universe Today via email, “but I needed all the right conditions.”
The challenge? Capture a transit of the International Space Station of not just the Sun — which he’s done dozens of times — but in front of a solar prominence.
Legault said the transit of the prominence, which he captured on August 21, 2015, lasted 0.8 seconds. His camera was running at 40 frames per second, and he got about 32 shots in that time.
See a video of the transit in real time, and more, below:
We’ve described in our previous articles how Legault determines the exact location where he needs to be to capture the images he wants by considering the width of the visibility path, and trying to be as close to the center of the path as possible. But this challenge was a bit different.
“I took the last transit data from Calsky, the real position of the prominences, and made angles and distances calculations to place my telescope this time not on the central line of the transit but 1 mile north from it,” Legault said, “to have the ISS passing in front of the largest prominence.”
You can see some of Legault’s stunning and sometimes ground-breaking astrophotography here on Universe Today, such as images of the space shuttle or International Space Station crossing the Sun or Moon, or views of spy satellites in orbit.
If you want to try and master the art of astrophotography, you can learn from Legault by reading his book, “Astrophotography,” which is available on Amazon in a large format book or as a Kindle edition for those who might like to have a lit version while out in the field. It is also available at book retailers like Barnes and Noble and Shop Indie bookstores, or from the publisher, Rocky Nook, here.
Levi Joraanstad, a student at North Dakota State University displays his telescope, which police mistook for a rifle. Image via WDAY TV, Fargo, North Dakota.
One more thing amateur astronomers might need to worry about besides clouds, bugs, and trying to fix equipment malfunctions in the dark – and this one’s a little more serious.
Earlier this week, two students at North Dakota State University (NDSU) in Fargo, North Dakota were settting up a telescope and camera system to take pictures of the Moon when armed police approached them. The police officers had mistaken the telescope for a rifle.
Students Levi Joraanstad and Colin Waldera told WDAY TV in Fargo that they were were setting up their telescope behind their apartment’s garage when they were blinded by a bright light and told to stop moving.
Initially, they thought it was a joke, that fellow students were pulling a prank, and because police were shining a bright light at them, the two students were blinded.
Police said that an officer patrolling the area had seen what he thought was suspicious activity behind the garage, thinking that one of the students’ dark sweater with white lettering on the back looked like a tactical vest, and that the telescope might be a rifle.
Police added that their response was a “better safe than sorry” approach, and they said the two students were never in any danger of being shot.
However, Joraanstad and Waldera said since they thought it was a joke, they initially ignored the order to stop moving and kept digging in their bags for equipment.
“I was kind of fumbling around with my stuff and my roommate and I were kind of talking, we were kind of wondering, what the heck’s going on? This is pretty dum that these guys are doing this,” WDAY quoted Joraanstad, a junior at NDSU. “And then they started shouting to quit moving or we could be shot. And so at that moment we kind of look at each other and we’re thinking we better take this seriously.”
If the police had acted more aggressively, the outcome could have been tragic. Joraanstad said the officers were very apologetic when they realized their mistake, and they explained what had happened.
So, watch where and how you point your telescope.
This is a rare occurrence, of course, and is nothing like risks amateur astronomers in Afghanistan regularly take to look through a telescope and share their views with local people. We wrote an article — which you can read here — about how they have to deal with more serious complications, such as making sure the area is clear of land mines, not arousing the suspicions the Taliban or the local police, and watching out for potential bombing raids by the US/UK/Afghan military alliance.
UPDATE: Maybe incidents like this aren’t quite as rare as I thought. Universe Today’s Bob King told me that just two weeks ago he was out observing in the countryside, when a very similar event happened to him. “A truck pulled up fast, with bright lights blinding my eyes and then the sheriff walked out of the car,” Bob said. “I quickly identified myself and explained what I was up to. He thought I was burying a dead body! No kidding.”
NASA's Dawn spacecraft spotted this tall, conical mountain on Ceres from a distance of 915 miles (1,470 kilometers). The mountain, located in the southern hemisphere, stands 4 miles (6 kilometers) high. Its perimeter is sharply defined, with almost no accumulated debris at the base of the brightly streaked slope. The image was taken on August 19, 2015.Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
The Dawn spacecraft is now orbiting just 1,470 kilometers (915 miles) above Ceres’ surface, and the science team released these latest images. Above is a closest view yet of the so-called ‘pyramid’ on Ceres, although the closer Dawn gets, the less this feature looks like a pyramid. It’s actually more like a conical mountain with a flat top, almost like a butte.
And if you’re like me and you see a crater instead of a mountain, just turn the picture over (or stand on your head). Below, we’ve turned the image upside down for you:
An upside down look at the conical mountain on Ceres (in case you have trouble seeing it as a mountain!). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
The mountain is located in the southern hemisphere, and stands 6 kilometers (4 miles) high. Visible on the sides of the mountain are narrow braided fractures and an intriguing bright area. Only time will tell if this bright region is similar to the mysterious bright spots seen in previous Dawn images of Ceres. The team released additional images as well.
This image, taken by NASA’s Dawn spacecraft, shows high southern latitudes on Ceres from an altitude of 2,700 miles (4,400 kilometers). Zadeni crater, measuring about 80 miles (130 kilometers) across, is on the right side of the image. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
As Dawn slowly moves ever-closer to Ceres surface, the team says the spacecraft is performing well.
“Dawn is performing flawlessly in this new orbit as it conducts its ambitious exploration. The spacecraft’s view is now three times as sharp as in its previous mapping orbit, revealing exciting new details of this intriguing dwarf planet,” said Marc Rayman, Dawn’s chief engineer and mission director, based at NASA’s Jet Propulsion Laboratory, Pasadena,
Dawn is currently taking images to try and map the entire surface. This will 11 days at this altitude and each 11-day cycle consists of 14 orbits. Over the next two months, the spacecraft will map the entirety of Ceres six times.
This image, taken by NASA’s Dawn spacecraft, shows high southern latitudes on Ceres from an altitude of 2,700 miles (4,400 kilometers). Zadeni crater, measuring about 80 miles (130 kilometers) across, is on the right side of the image. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Using Dawn’s framing camera to map the surface in detail, scientists hope to create a 3-D modeling of Ceres’ surface. Every image from this orbit has a resolution of 450 feet (140 meters) per pixel, and covers less than 1 percent of the surface of Ceres.
At the same time, Dawn’s visible and infrared mapping spectrometer is collecting data that will give scientists a better understanding of the minerals found on Ceres’ surface.
The science and engineering teams are also taking a look at the data coming in from radio signals to help with measurements of Ceres’ gravity field. This will help determine the distribution of mass on Ceres interior and might provide clues if the asteroid has any liquid water beneath its surface.
Additionally, the radio data data will help mission planners design the maneuvers for lowering Dawn’s orbit even more. In late October, Dawn will begin spiraling toward this final orbit, which will be at an altitude of 375 kilometers (230 miles.)
In the latest entry on the Dawn Journal, Rayman said despite the loss of the reaction wheels (in 2010 and 2012) that help maneuver the spacecraft and keep it stable, engineers have learned how to be very efficient with the precious hydrazine the fuels the small jets of the reaction control system and they now have some to spare. They now expect to exceed the original mission parameters!
“Therefore, mission planners have recently decided to spend a few more in this mapping orbit,” Rayman said. “They have added extra turns to allow the robot to communicate with Earth during more of the transits over the nightside than they had previously budgeted. This means Dawn can send the contents of its computer memory to Earth more often and therefore have space to collect and store even more data than originally planned. An 11-day mapping cycle is going to be marvelously productive.”
There’s still a debate about the unusually bright spots in some of Ceres craters that appear when the asteroid/dwarf planet turns into the sunlight. The team has speculated that they could be frozen pools of water ice, or patches of light-colored, salt-rich material.
The brightest spots are known collectively as Spot 5, and sit inside Occator Crater on Ceres, and hopefully new images of this area will be released soon. In a previous article on Universe Today, Dawn’s principal investigator, Chris Russell of the University of California at Los Angeles told us that the debate is continuing among the science team, but he wouldn’t harbor a guess as to which way the debate might end or which “side” was in the lead among the scientists.
“I originally was an advocate of ice, because of how bright the spots seemed to be,” Russell told writer Alan Boyle, but newer observations revealed the bright material’s albedo, or reflectivity factor, is about 50 percent – which is less than Russell originally thought. “This could be salt and is unlikely to be ice. I think the team opinion is now more in line with salt,” he said.
You can cast your vote as to what you think the bright spots are at this NASA page.
Need an easy way to remember the order of the planets in our Solar System? The technique used most often to remember such a list is a mnemonic device. This uses the first letter of each planet as the first letter of each word in a sentence. Supposedly, experts say, the sillier the sentence, the easier it is to remember.
So by using the first letters of the planets, (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune), create a silly but memorable sentence.
Here are a few examples:
My Very Excellent Mother Just Served Us Noodles (or Nachos)
Mercury’s Volcanoes Erupt Mulberry Jam Sandwiches Until Noon
Very Elderly Men Just Snooze Under Newspapers
My Very Efficient Memory Just Summed Up Nine
My Very Easy Method Just Speeds Up Names
My Very Expensive Malamute Jumped Ship Up North
The Sun and planets to scale. Credit: Illustration by Judy Schmidt, texture maps by Björn Jónsson
If you want to remember the planets in order of size, (Jupiter, Saturn, Uranus, Neptune, Earth, Venus Mars, Mercury) you can create a different sentence:
Just Sit Up Now Each Monday Morning
Jack Sailed Under Neath Every Metal Mooring
Rhymes are also a popular technique, albeit they require memorizing more words. But if you’re a poet (and don’t know it) try this:
Amazing Mercury is closest to the Sun,
Hot, hot Venus is the second one,
Earth comes third: it’s not too hot,
Freezing Mars awaits an astronaut,
Jupiter is bigger than all the rest,
Sixth comes Saturn, its rings look best,
Uranus sideways falls and along with Neptune, they are big gas balls.
Or songs can work too. Here are a couple of videos that use songs to remember the planets:
If sentences, rhymes or songs don’t work for you, perhaps you are more of a visual learner, as some people remember visual cues better than words. Try drawing a picture of the planets in order. You don’t have to be an accomplished artist to do this; you can simply draw different circles for each planet and label each one. Sometimes color-coding can help aid your memory. For example, use red for Mars and blue for Neptune. Whatever you decide, try to pick colors that are radically different to avoid confusing them.
Or try using Solar System flash cards or just pictures of the planets printed on a page (here are some great pictures of the planets). This works well because not only are you recalling the names of the planets but also what they look like. Memory experts say the more senses you involve in learning or storing something, the better you will be at recalling it.
Planets made from paper lanterns. Credit: TheSweetestOccasion.com
Maybe you are a hands-on learner. If so, try building a three-dimensional model of the Solar System. Kids, ask your parents or guardians to help you with this, or parents/guardians, this is a fun project to do with your children. You can buy inexpensive Styrofoam balls at your local craft store to create your model, or use paper lanterns and decorate them. Here are several ideas from Pinterest on building a 3-D Solar System Model.
If you are looking for a group project to help a class of children learn the planets, have a contest to see who comes up with the silliest sentence to remember the planets. Additionally, you can have eight children act as the planets while the rest of the class tries to line them up in order. You can find more ideas on NASA’s resources for Educators. You can use these tricks as a starting point and find more ways of remembering the planets that work for you.
