Two years ago today (July 14), our New Horizons spacecraft made its closest flyby of Pluto…collecting images and science that revealed a geologically complex world. Data from this mission are helping us understand worlds at the edge of our solar system.
The spacecraft is now venturing deeper into the distant, mysterious Kuiper Belt…a relic of solar system formation…to reach its next target. On New Year’s Day 2019, New Horizons will zoom past a Kuiper Belt object known as 2014 MU69.
The Kuiper Belt is a disc-shaped region of icy bodies – including dwarf planets such as Pluto – and comets beyond the orbit of Neptune. It extends from about 30 to 55 Astronomical Units (an AU is the distance from the sun to Earth) and is probably populated with hundreds of thousands of icy bodies larger than 62 miles across, and an estimated trillion or more comets.
Nearly a billion miles beyond Pluto, you may be asking how the spacecraft will function for the 2014 MU69 flyby. Well, New Horizons was originally designed to fly far beyond the Pluto system and explore deeper into the Kuiper Belt.
The spacecraft carries extra hydrazine fuel for the flyby; its communications system is designed to work from beyond Pluto; its power system is designed to operate for many more years; and its scientific instruments were designed to operate in light levels much lower than it will experience during the 2014 MU69 flyby.
What have we learned about Pluto since its historic flyby in 2015?
During its encounter, the New Horizons spacecraft collected more than 1,200 images of Pluto and tens of gigabits of data. The intensive downlinking of information took about a year to return to Earth! Here are a few things we’ve discovered:
Pluto Has a Heart
This image captured by New Horizons around 16 hours before its closest approach shows Pluto’s “heart.” This stunning image of one of its most dominant features shows us that the heart’s diameter is about the same distance as from Denver to Chicago. This image also showed us that Pluto is a complex world with incredible geological diversity.
Pluto’s vast icy plain, informally called Sputnik Planitia, resembles frozen mud cracks on Earth. It has a broken surface of irregularly-shaped segments, bordered by what appear to be shallow troughs.
Images from the spacecraft display chaotically jumbled mountains that only add to the complexity of Pluto’s geography. The rugged, icy mountains are as tall as 11,000 feet high.
This high-resolution enhanced color view of Pluto combines blue, red and infrared images taken by the New Horizons spacecraft. The surface of Pluto has a remarkable range of subtle color variations. Many landforms have their own distinct colors, telling a complex geological and climatological story.
Foggy Haze and Blue Atmosphere
Images returned from the New Horizons spacecraft have also revealed that Pluto’s global atmospheric haze has many more layers than scientists realized. The haze even creates a twilight effect that softly illuminates nightside terrain near sunset, which makes them visible to the cameras aboard the spacecraft.
New Horizons detected numerous small, exposed regions of water ice on Pluto. Scientists are eager to understand why water appears exactly where it does, and not in other places.
The Past, Present and Future of Exploration on Mars
Today, we’re celebrating the Red Planet! Since our first close-up picture of Mars in 1965, spacecraft voyages to the Red Planet have revealed a world strangely familiar, yet different enough to challenge our perceptions of what makes a planet work.
You’d think Mars would be easier to understand. Like Earth, Mars has polar ice caps and clouds in its atmosphere, seasonal weather patterns, volcanoes, canyons and other recognizable features. However, conditions on Mars vary wildly from what we know on our own planet.
Join us as we highlight some of the exploration on Mars from the past, present and future:
Our Viking Project found a place in history when it became the first U.S. mission to land a spacecraft safely on the surface of Mars and return images of the surface. Two identical spacecraft, each consisting of a lander and an orbiter, were built. Each orbiter-lander pair flew together and entered Mars orbit; the landers then separated and descended to the planet’s surface.
Besides taking photographs and collecting other science data, the two landers conducted three biology experiments designed to look for possible signs of life.
In 1997, Pathfinder was the first-ever robotic rover to land on the surface of Mars. It was designed as a technology demonstration of a new way to deliver an instrumented lander to the surface of a planet. Mars Pathfinder used an innovative method of directly entering the Martian atmosphere, assisted by a parachute to slow its descent and a giant system of airbags to cushion the impact.
Pathfinder not only accomplished its goal but also returned an unprecedented amount of data and outlived its primary design life.
Spirit and Opportunity
In January 2004, two robotic geologists named Spirit and Opportunity landed on opposite sides of the Red Planet. With far greater mobility than the 1997 Mars Pathfinder rover, these robotic explorers have trekked for miles across the Martian surface, conducting field geology and making atmospheric observations. Carrying identical, sophisticated sets of science instruments, both rovers have found evidence of ancient Martian environments where intermittently wet and habitable conditions existed.
Both missions exceeded their planned 90-day mission lifetimes by many years. Spirit lasted 20 times longer than its original design until its final communication to Earth on March 22, 2010. Opportunity continues to operate more than a decade after launch.
Mars Reconnaissance Orbiter
Our Mars Reconnaissance Orbiter left Earth in 2005 on a search for evidence that water persisted on the surface of Mars for a long period of time. While other Mars missions have shown that water flowed across the surface in Mars’ history, it remained a mystery whether water was ever around long enough to provide a habitat for life.
In addition to using the rover to study Mars, we’re using data and imagery from this mission to survey possible future human landing sites on the Red Planet.
The Curiosity rover is the largest and most capable rover ever sent to Mars. It launched November 26, 2011 and landed on Mars on Aug. 5, 2012. Curiosity set out to answer the question: Did Mars ever have the right environmental conditions to support small life forms called microbes?
Early in its mission, Curiosity’s scientific tools found chemical and mineral evidence of past habitable environments on Mars. It continues to explore the rock record from a time when Mars could have been home to microbial life.
Space Launch System Rocket
We’re currently building the world’s most powerful rocket, the Space Launch System (SLS). When completed, this rocket will enable astronauts to begin their journey to explore destinations far into the solar system, including Mars.
The Orion spacecraft will sit atop the Space Launch System rocket as it launches humans deeper into space than ever before. Orion will serve as the exploration vehicle that will carry the crew to space, provide emergency abort capability, sustain the crew during the space travel and provide safe re-entry from deep space return velocities.
The Mars 2020 rover mission takes the next step in exploration of the Red Planet by not only seeking signs of habitable conditions in the ancient past, but also searching for signs of past microbial life itself.
The Mars 2020 rover introduces a drill that can collect core samples of the most promising rocks and soils and set them aside in a “cache” on the surface of Mars. The mission will also test a method for producing oxygen from the Martian atmosphere, identify other resources (such as subsurface water), improve landing techniques and characterize weather, dust and other potential environmental conditions that could affect future astronauts living and working on the Red Planet.
For decades, we’ve sent orbiters, landers and rovers, dramatically increasing our knowledge about the Red Planet and paving the way for future human explorers. Mars is the next tangible frontier for human exploration, and it’s an achievable goal. There are challenges to pioneering Mars, but we know they are solvable.
Because space is vast and full of mysteries, NASA is developing a new rocket, a new spacecraft for astronauts and new facilities to launch them from. Our Space Launch System will be unlike any other rocket when it takes flight. It will be bigger, bolder and take astronauts and cargo farther than humankind has ever been – to deep space destinations like the moon, a deep space gateway or even Mars.
When you plan to get to space, you use ice and fire. NASA’s Space Launch System uses four rocket engines in the center of the rocket and a pair of solid rocket boosters on opposite sides. All this power will propel the Space Launch System to gravity-slaying speeds of more than 17,000 miles per hour! These are the things we do for space exploration, the greatest adventure that ever was or will be.
It is Known
It is known that according to Newton’s third law, for every action there is an equal and opposite reaction. That’s how rocket propulsion works. Fuel burned in combustion chambers causes hot gases to shoot out the bottom of the engine nozzles. This propels the rocket upward.
It is also known that when you combine hydrogen and oxygen you get: water. To help SLS get to space, the rocket’s four RS-25 engines shoot hydrogen and oxygen together at high speeds, making billowing clouds of steaming hot water vapor. The steam, funneled through the engine nozzles, expands with tremendous force and helps lift the rocket from the launchpad.
RS-25: Ice King
It takes a lot of fuel (hydrogen) and a lot of oxygen to make a chemical reaction powerful enough to propel a rocket the size of a skyscraper off the launch pad. To fit more hydrogen and oxygen into the tanks in the center of the rocket where they’re stored, the hydrogen and oxygen are chilled to as low as -400 degrees Fahrenheit. At those temperatures, the gases become icy liquids.
The Fire that Burns Against the Cold
The hydrogen-oxygen reaction inside the nozzles can reach temperatures up to 6,000 degrees Fahrenheit (alas, only Valyrian steel could withstand those temperatures)! To protect the nozzle from this heat, the icy hydrogen is pumped through more than a thousand small pipes on the outside of the nozzle to cool it. After the icy liquid protects the metal nozzles, it becomes fuel for the engines.
Where is my FIRE?
The Space Launch System solid rocket boosters are the fire and the breakers of gravity’s chains. The solid rocket boosters’ fiery flight lasts for two minutes. They burn solid fuel that’s a potent mixture of chemicals the consistency of a rubber eraser. When the boosters light, hot gases and fire are unleashed at speeds up to three times the speed of sound, propelling the vehicle to gravity-slaying speed in seconds.
Testing is Here
To make sure everything works on a rocket this big, it takes a lot of testing before the first flight. Rocket hardware is rolling off production lines all over the United States and being shipped to testing locations nationwide. Some of that test hardware includes replicas of the giant tanks that will hold the icy hydrogen and oxygen.
As Rare as Dragonglass
Other tests include firing the motor for the solid rocket boosters. The five-segment motor is the largest ever made for spaceflight and the part that contains the propellant that burns for two fiery, spectacular minutes. It’s common during ground test firings for the fiery exhaust to turn the sand in the Utah desert to glass.
Hold the Door
When all the hardware, software and avionics for SLS are ready, they will be shipped to Kennedy Space Center where the parts will be assembled to make the biggest rocket since the Saturn V. Then, technicians will stack Orion, NASA’s new spacecraft for taking astronauts to deep space, on top of SLS. All this work to assemble America’s new heavy-lift rocket and spacecraft will be done in the Vehicle Assembly Building – one of the largest buildings in the world. Hold the door to the Vehicle Assembly Building open, because SLS and Orion are coming!