A human journey to Mars, at first glance, offers an inexhaustible amount
of complexities. To bring a mission to the Red Planet from fiction to fact, our Human
Research Program has
organized some of the hazards astronauts will encounter on a continual basis
into five classifications.
The third and perhaps most apparent hazard is, quite
simply, the distance.
Rather than a three-day lunar trip, astronauts would
be leaving our planet for roughly three years. Facing a communication delay of
up to 20 minutes one way and the possibility of equipment failures or a medical
emergency, astronauts must be capable of confronting an array of situations
without support from their fellow team on Earth.
Once you burn your engines for Mars, there is no
turning back so planning and self-sufficiency are essential keys to a
successful Martian mission. The Human Research Program is studying and
improving food formulation, processing, packaging and preservation systems.
While International Space Station expeditions serve as
a rough foundation for the expected impact on planning logistics for such a
trip, the data isn’t always comparable, but it is a key to the solution.
Exploration to the Moon and Mars
will expose astronauts to five known hazards of spaceflight, including distance
from Earth. To learn more, and find out what our Human Research
Program is doing to protect humans in space, check out the “Hazards
of Human Spaceflight" website. Or,
check out this week’s episode of “Houston We Have a Podcast,” in which host Gary Jordan
further dives into the threat of distance with Erik Antonsen, the
Assistant Director for Human Systems Risk
Management at the Johnson Space Center.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.A human journey to Mars, at first glance, offers an inexhaustible amount of complexities. To bring a mission to the Red Planet from fiction to fact, our Human Research Program has organized hazards astronauts will encounter on a continual basis into five classifications. (View the first hazard). Let’s dive into the second hazard:
Overcoming the second hazard, isolation and confinement, is essential for a successful mission to Mars. Behavioral issues among groups of people crammed in a small space over a long period of time, no matter how well trained they are, are inevitable. It is a topic of study and discussion currently taking place around the selection and composition of crews.
On Earth, we have the luxury of picking up our cell phones and instantly being connected with nearly everything and everyone around us.
On a trip to Mars, astronauts will be more isolated and confined than we can imagine.
Sleep loss, circadian desynchronization (getting out of sync), and work overload compound this issue and may lead to performance decrements or decline, adverse health outcomes, and compromised mission objectives.
To address this hazard, methods for monitoring behavioral health and adapting/refining various tools and technologies for use in the spaceflight environment are being developed to detect and treat early risk factors. Research is also being conducted in workload and performance, light therapy for circadian alignment or internal clock alignment, and team cohesion.
Exploration to the Moon and Mars will expose astronauts to five known hazards of spaceflight, including isolation and confinement. To learn more, and find out what the Human Research Program is doing to protect humans in space, check out the “Hazards of Human Spaceflight” website. Or, check out this week’s episode of “Houston We Have a Podcast,” in which host Gary Jordan further dives into the threat of isolation and confinement with Tom Williams, a NASA Human Factors and Behavior Performance Element Scientist at the Johnson Space Center.
Our Spitzer Space Telescope is celebrating 15 years since its launch on August 25, 2003. This remarkable spacecraft has made discoveries its designers never even imagined, including some of the seven Earth-size planets of TRAPPIST-1. Here are some key facts about Spitzer:
1. Spitzer is one of our Great Observatories.
Our Great Observatory Program aimed to explore the universe with four large space telescopes, each specialized in viewing the universe in different wavelengths of light. The other Great Observatories are our Hubble Space Telescope, Chandra X-Ray Observatory, and Compton Gamma-Ray Observatory. By combining data from different kinds of telescopes, scientists can paint a fuller picture of our universe.
2. Spitzer operates in infrared light.
Infrared wavelengths of light, which primarily come from heat radiation, are too long to be seen with human eyes, but are important for exploring space — especially when it comes to getting information about something extremely far away. From turbulent clouds where stars are born to small asteroids close to Earth’s orbit, a wide range of phenomena can be studied in infrared light. Objects too faint or distant for optical telescopes to detect, hidden by dense clouds of space dust, can often be seen with Spitzer. In this way, Spitzer acts as an extension of human vision to explore the universe, near and far.
What’s more, Spitzer doesn’t have to contend with Earth’s atmosphere, daily temperature variations or day-night cycles, unlike ground-based telescopes. With a mirror less than 1 meter in diameter, Spitzer in space is more sensitive than even a 10-meter-diameter telescope on Earth.
3. Spitzer was the first spacecraft to fly in an Earth-trailing orbit.
Rather than circling Earth, as Hubble does, Spitzer orbits the Sun on almost the same path as Earth. But Spitzer moves slower than Earth, so the spacecraft drifts farther away from our planet each year.
This “Earth-trailing orbit” has many advantages. Being farther from Earth than a satellite, it receives less heat from our planet and enjoys a naturally cooler environment. Spitzer also benefits from a wider view of the sky by orbiting the Sun. While its field of view changes throughout the year, at any given time it can see about one-third of the sky. Our Kepler space telescope, famous for finding thousands of exoplanets – planets outside our solar system – also settled in an Earth-trailing orbit six years after Spitzer.
4. Spitzer began in a “cold mission.”
Spitzer has far outlived its initial requirement of 2.5 years. The Spitzer team calls the first 5.5 years “the cold mission” because the spacecraft’s instruments were deliberately cooled down during that time. Liquid helium coolant kept Spitzer’s instruments just a few degrees above absolute zero (which is minus 459 degrees Fahrenheit, or minus 273 degrees Celsius) in this first part of the mission.
5. The “warm mission” was still pretty cold.
Spitzer entered what was called the “warm mission” when the 360 liters of liquid helium coolant that was chilling its instruments ran out in May 2009.
At the “warm” temperature of minus 405 Fahrenheit, two of Spitzer’s instruments – the Infrared Spectrograph (IRS) and Multiband Imaging Photometer (MIPS) – stopped working. But two of the four detector arrays in the Infrared Array Camera (IRAC) persisted. These “channels” of the camera have driven Spitzer’s explorations since then.
6. Spitzer wasn’t designed to study exoplanets, but made huge strides in this area.
Exoplanet science was in its infancy in 2003 when Spitzer launched, so the mission’s first scientists and engineers had no idea it could observe planets beyond our solar system. But the telescope’s accurate star-targeting system and the ability to control unwanted changes in temperature have made it a useful tool for studying exoplanets. During the Spitzer mission, engineers have learned how to control the spacecraft’s pointing more precisely to find and characterize exoplanets, too.
Using what’s called the “transit method,” Spitzer can stare at a star and detect periodic dips in brightness that happen when a planet crosses a star’s face. In one of its most remarkable achievements, Spitzer discovered three of the TRAPPIST-1 planets and confirmed that the system has seven Earth-sized planets orbiting an ultra-cool dwarf star. Spitzer data also helped scientists determine that all seven planets are rocky, and made these the best-understood exoplanets to date.
Spitzer can also use a technique called microlensing to find planets closer to the center of our galaxy. When a star passes in front of another star, the gravity of the first star can act as a lens, making the light from the more distant star appear brighter. Scientists are using microlensing to look for a blip in that brightening, which could mean that the foreground star has a planet orbiting it. Microlensing could not have been done early in the mission when Spitzer was closer to Earth, but now that the spacecraft is farther away, it has a better chance of measuring these events.
7. Spitzer is a window into the distant past.
The spacecraft has observed and helped discover some of the most distant objects in the universe, helping scientists understand where we came from. Originally, Spitzer’s camera designers had hoped the spacecraft would detect galaxies about 12 billion light-years away. In fact, Spitzer has surpassed that, and can see even farther back in time – almost to the beginning of the universe. In collaboration with Hubble, Spitzer helped characterize the galaxy GN-z11 about 13.4 billion light-years away, whose light has been traveling since 400 million years after the big bang. It is the farthest galaxy known.
8. Spitzer discovered Saturn’s largest ring.
Everyone knows Saturn has distinctive rings, but did you know its largest ring was only discovered in 2009, thanks to Spitzer? Because this outer ring doesn’t reflect much visible light, Earth-based telescopes would have a hard time seeing it. But Spitzer saw the infrared glow from the cool dust in the ring. It begins 3.7 million miles (6 million kilometers) from Saturn and extends about 7.4 million miles (12 million kilometers) beyond that.
9. The “Beyond Phase” pushes Spitzer to new limits.
In 2016, Spitzer entered its “Beyond phase,” with a name reflecting how the spacecraft operates beyond its original scope.
As Spitzer floats away from Earth, its increasing distance presents communication challenges. Engineers must point Spitzer’s antenna at higher angles toward the Sun in order to talk to our planet, which exposes the spacecraft to more heat. At the same time, the spacecraft’s solar panels receive less sunlight because they point away from the Sun, putting more stress on the battery.
The team decided to override some autonomous safety systems so Spitzer could continue to operate in this riskier mode. But so far, the Beyond phase is going smoothly.
10. Spitzer paves the way for future infrared telescopes.
Spitzer has identified areas of further study for our upcoming James Webb Space Telescope, planned to launch in 2021. Webb will also explore the universe in infrared light, picking up where Spitzer eventually will leave off. With its enhanced ability to probe planetary atmospheres, Webb may reveal striking new details about exoplanets that Spitzer found. Distant galaxies unveiled by Spitzer together with other telescopes will also be observed in further detail by Webb. The space telescope we are planning after that, WFIRST, will also investigate long-standing mysteries by looking at infrared light. Scientists planning studies with future infrared telescopes will naturally build upon the pioneering legacy of Spitzer.
Read the web version of this week’s “Solar System: 10 Things to Know” article HERE.
A human journey to Mars, at first glance, offers an inexhaustible amount of complexities. To bring a mission to the Red Planet from fiction to fact, our Human Research Program has organized hazards astronauts will encounter on a continual basis into five classifications.
The first hazard of a human mission to Mars is also the most difficult to visualize because, well, space radiation is invisible to the human eye. Radiation is not only stealthy, but considered one of the most menacing of the five hazards.
Above Earth’s natural protection, radiation exposure increases cancer risk, damages the central nervous system, can alter cognitive function, reduce motor function and prompt behavioral changes. To learn what can happen above low-Earth orbit, we study how radiation affects biological samples using a ground-based research laboratory.
Exploration to the Moon and Mars will expose astronauts to five known hazards of spaceflight, including radiation. To learn more, and find out what our Human Research Program is doing to protect humans in space, check out the “Hazards of Human Spaceflight” website or check out this week’s episode of “Houston We Have a Podcast,” in which our host Gary Jordan further dives into the threat of radiation with Zarana Patel, a radiation lead scientist at the Johnson Space Center.
To most of us, dust is an annoyance. Something to be cleaned up, washed off or wiped away. But these tiny particles that float about and settle on surfaces play an important role in a variety of processes on Earth and across the solar system. So put away that feather duster for a few moments, as we share with you 10 things to know about dust.
1. “Dust” Doesn’t Mean Dirty, it Means Tiny
Not all of what we call “dust” is made of the same stuff. Dust in your home generally consists of things like particles of sand and soil, pollen, dander (dead skin cells), pet hair, furniture fibers and cosmetics. But in space, dust can refer to any sort of fine particles smaller than a grain of sand. Dust is most commonly bits of rock or carbon-rich, soot-like grains, but in the outer solar system, far from the Sun’s warmth, it’s also common to find tiny grains of ice as well. Galaxies, including our Milky Way, contain giant clouds of fine dust that are light years across – the ingredients for future generations of planetary systems like ours.
2. Some Are Big, Some Are Small (and Big Ones Tend to Fall)
Dust grains come in a range of sizes, which affects their properties. Particles can be extremely tiny, from only a few tens of nanometers (mere billionths of a meter) wide, to nearly a millimeter wide. As you might expect, smaller dust grains are more easily lifted and pushed around, be it by winds or magnetic, electrical and gravitational forces. Even the gentle pressure of sunlight is enough to move smaller dust particles in space. Bigger particles tend to be heavier, and they settle out more easily under the influence of gravity.
For example, on Earth, powerful winds can whip up large amounts of dust into the atmosphere. While the smaller grains can be transported over great distances, the heavier particles generally sink back to the ground near their source. On Saturn’s moon Enceladus, jets of icy dust particles spray hundreds of miles up from the surface; the bigger particles are lofted only a few tens of miles (or kilometers) and fall back to the ground, while the finest particles escape the moon’s gravity and go into orbit around Saturn to create the planet’s E ring.
3. It’s EVERYWHERE
Generally speaking, the space between the planets is pretty empty, but not completely so. Particles cast off by comets and ground up bits of asteroids are found throughout the solar system. Take any volume of space half a mile (1 kilometer) on a side, and you’d average a few micron-sized particles (grains the thickness of a red blood cell).
Dust in the solar system was a lot more abundant in the past. There was a huge amount of it present as the planets began to coalesce out of the disk of material that formed the Sun. In fact, motes of dust gently sticking together were likely some of the earliest seeds of the planet-building process. But where did all that dust come from, originally? Some of it comes from stars like our Sun, which blow off their outer layers in their later years. But lots of it also comes from exploding stars, which blast huge amounts of dust and gas into space when they go boom.
4. From a Certain Point of View
Dust is easier to see from certain viewing angles. Tiny particles scatter light depending on how big their grains are. Larger particles tend to scatter light back in the direction from which it came, while very tiny particles tend to scatter light forward, more or less in the direction it was already going. Because of this property, structures like planetary rings made of the finest dusty particles are best viewed with the Sun illuminating them from behind. For example, Jupiter’s rings were only discovered after the Voyager 1 spacecraft passed by the planet, where it could look back and see them backlit by the Sun. You can see the same effect looking through a dusty windshield at sunset; when you face toward the Sun, the dust becomes much more apparent.
5. Dust Storms Are Common on Mars
Local dust storms occur frequently on Mars, and occasionally grow or merge to form regional systems, particularly during the southern spring and summer, when Mars is closest to the Sun. On rare occasions, regional storms produce a dust haze that encircles the planet and obscures surface features beneath. A few of these events may become truly global storms, such as one in 1971 that greeted the first spacecraft to orbit Mars, our Mariner 9. In mid-2018, a global dust storm enshrouded Mars, hiding much of the Red Planet’s surface from view and threatening the continued operation of our uber long-lived Opportunity rover. We’ve also seen global dust storms in 1977, 1982, 1994, 2001 and 2007.
Dust storms will likely present challenges for future astronauts on the Red Planet. Although the force of the wind on Mars is not as strong as portrayed in an early scene in the movie “The Martian,” dust lofted during storms could affect electronics and health, as well as the availability of solar energy.
6. Dust From the Sahara Goes Global
Earth’s largest, hottest desert is connected to its largest tropical rain forest by dust. The Sahara Desert is a near-uninterrupted brown band of sand and scrub across the northern third of Africa. The Amazon rain forest is a dense green mass of humid jungle that covers northeast South America. But after strong winds sweep across the Sahara, a dusty cloud rises in the air, stretches between the continents, and ties together the desert and the jungle.
This trans-continental journey of dust is important because of what is in the dust. Specifically, the dust picked up from the Bodélé Depression in Chad – an ancient lake bed where minerals composed of dead microorganisms are loaded with phosphorus. Phosphorus is an essential nutrient for plant proteins and growth, which the nutrient-poor Amazon rain forest depends on in order to flourish.
7. Rings and Things
The rings of the giant planets contain a variety of different dusty materials. Jupiter’s rings are made of fine rock dust. Saturn’s rings are mostly pure water ice, with a sprinkling of other materials. (Side note about Saturn’s rings: While most of the particles are boulder-sized, there’s also lots of fine dust, and some of the fainter rings are mostly dust with few or no large particles.) Dust in the rings of Uranus and Neptune is made of dark, sooty material, probably rich in carbon.
Over time, dust gets removed from ring systems due to a variety of processes. For example, some of the dust falls into the planet’s atmosphere, while some gets swept up by the planets’ magnetic fields, and other dust settles onto the surfaces of the moons and other ring particles. Larger particles eventually form new moons or get ground down and mixed with incoming material. This means rings can change a lot over time, so understanding how the tiniest ring particles are being moved about has bearing on the history, origins and future of the rings.
8. Moon Dust is Clingy and Might Make You Sick
So, dust is kind of a thing on the Moon. When the Apollo astronauts visited the Moon, they found that lunar dust quickly coated their spacesuits and was difficult to remove. It was quite abrasive, causing wear on their spacesuit fabrics, seals and faceplates. It also clogged mechanisms like the joints in spacesuit limbs, and interfered with fasteners like zippers and Velcro. The astronauts also noted that it had a distinctive, pungent odor, not unlike gunpowder, and it was an eye and lung irritant.
Many of these properties apparently can be explained by the fact that lunar dust particles are quite rough and jagged. While dust particles on Earth get tumbled and ground by the wind into smoother shapes, this sort of weathering doesn’t happen so much on the Moon. The roughness of Moon dust grains makes it very easy for them to cling to surfaces and scratch them up. It also means they’re not the sort of thing you would want to inhale, as their jagged edges could damage delicate tissues in the lung.
9. Dust is What Makes Comets So Pretty
Most comets are basically clods of dust, rock and ice. They spend most of their time far from the Sun, out in the refrigerated depths of the outer solar system, where they’re peacefully dormant. But when their orbits carry them closer to the Sun – that is, roughly inside the orbit of Jupiter – comets wake up. In response to warming temperatures, the ices on and near their surfaces begin to turn into gases, expanding outward and away from the comet, and creating focused jets of material in places. Dust gets carried away by this rapidly expanding gas, creating a fuzzy cloud around the comet’s nucleus called a coma. Some of the dust also is drawn out into a long trail – the comet’s tail.
10. We’re Not the Only Ones Who’re So Dusty
Dust in our solar system is continually replenished by comets whizzing past the Sun and the occasional asteroid collision, and it’s always being moved about, thanks to a variety of factors like the gravity of the planets and even the pressure of sunlight. Some of it even gets ejected from our solar system altogether.
With telescopes, we also observe dusty debris disks around many other stars. As in our own system, the dust in such disks should evolve over time, settling on planetary surfaces or being ejected, and this means the dust must be replenished in those star systems as well. So studying the dust in our planetary environs can tell us about other systems, and vice versa. Grains of dust from other planetary systems also pass through our neighborhood – a few spacecraft have actually captured and analyzed some them – offering us a tangible way to study material from other stars.
Read the full version of ‘Solar System: 10 Things to Know’ article HERE.
Our Parker Solar Probe will get closer to the Sun than any spacecraft has ever gone – it will fly right through the Sun’s corona, part of the Sun’s atmosphere.
This spacecraft is full of cutting-edge technology, from its heat shield down to its guidance and control systems. It also carries four suites of advanced instruments designed to study the Sun in a multitude of ways.
1. Measuring particles
Two of Parker Solar Probe’s instrument suites are focused on measuring particles – electrons and ions – within the corona.
One of these particle-measuring instrument suites is SWEAP (Solar Wind Electrons Alphas and Protons). SWEAP counts the most common particles in the solar wind – the Sun’s constant outflow of material – and measures their properties, like velocity, density and temperature. Gathering this information about solar wind particles will help scientists better understand why the solar wind reaches supersonic speeds and exactly which part of the Sun the particles come from.
One instrument in the SWEAP suite is the Solar Probe Cup. Most of the instruments on Parker Solar Probe stay safe and cool in the shadow of the heat shield, but the Solar Probe Cup is one of the few that sticks out. That’s so it can capture and measure particles streaming straight out from the Sun, and it had to go through some intense testing to get ready for this position in the Sun’s incredibly hot corona.
Credit: Levi Hutmacher/Michigan Engineering
The ISʘIS suite (pronounced EE-sis, and including the symbol for the Sun in its acronym) also measures particles. ISʘIS is short for Integrated Science Investigation of the Sun, and this instrument suite measures particles that move faster – and therefore have more energy – than the solar wind.
These measurements will help scientists understand these particles’ lifecycles – where they came from, how they got to be traveling so fast (these particles can reach speeds more than half the speed of light!) and what path they take as they travel away from the Sun and into interplanetary space.
2. Taking pictures – but not of the Sun’s surface.
WISPR (Wide-Field Imager for Parker Solar Probe) has the only two cameras on Parker Solar Probe – but they’re not pointed directly at the Sun. Instead, WISPR looks out the side of the spacecraft, in the direction it’s traveling, looking at the space Parker Solar Probe is about to fly through. From that vantage point, WISPR captures images of structures within the corona like coronal mass ejections, or CMEs. CMEs are clouds of solar material that occasionally explode from the Sun at millions of miles per hour. Because this solar material is magnetized, CMEs can trigger geomagnetic storms when they reach Earth – which, in turn, can cause effects like auroras and even, in extreme cases, power outages.
Right now, our observations of events like these come from satellites orbiting near Earth, so WISPR will give us a whole new perspective. And, scientists will be able to combine WISPR’s images with Parker Solar Probe’s direct particle measurements to get a better idea of how these structures change as they travel.
3. Studying electric & magnetic fields
The FIELDS instrument suite is appropriately named: It’s what scientists will use to study the electric and magnetic fields in the corona.
Electric and magnetic fields are key to understanding what happens, not only on the Sun, but throughout space, because they the primary driver accelerating charged particles. In particular, a process called magnetic reconnection – when magnetic field lines explosively realign, sending particles rocketing away at incredible speeds – is thought to drive solar explosions, as well as space weather effects on Earth, like the aurora.
FIELDS measures electric and magnetic field at high time resolution, meaning it takes lots of measurements in a short amount of time, to track these processes and shed some light on the mechanics underlying the Sun’s behavior. FIELDS’ measurements are precisely synced up with those of the SWEAP suite (one of the sets of instruments studying particles) so that scientists can match up the immediate effects that electric and magnetic fields have on the material of the solar wind.
Parker Solar Probe launches summer 2018 on its mission to study the Sun. Keep up with the latest on the mission at nasa.gov/solarprobe or follow us on Twitter and Facebook.
Webb is our upcoming infrared space observatory, which will launch in 2021. It will spy the first luminous objects that formed in the universe and shed light on how galaxies evolve, how stars and planetary systems are born and how life could form on other planets.
1. Why is the mirror segmented?
The James Webb Space Telescope has a 6.5-meter (21.3-foot) diameter mirror, made from 18 individual segments. Webb needs to have an unfolding mirror because the mirror is so large that it otherwise cannot fit in the launch shroud of currently available rockets.
The mirror has to be large in order to see the faint light from the first star-forming regions and to see very small details at infrared wavelengths.
Designing, building and operating a mirror that unfolds is one of the major technological developments of Webb. Unfolding mirrors will be necessary for future missions requiring even larger mirrors, and will find application in other scientific, civil and military space missions.
2. Why are the mirrors hexagonal?
In short, the hexagonal shape allows a segmented mirror to be constructed with very small gaps, so the segments combine to form a roughly circular shape and need only three variations in size. If we had circular segments, there would be gaps between them.
Finally, we want a roughly circular overall mirror shape because that focuses the light into the most symmetric and compact region on the detectors.
An oval mirror, for example, would give images that are elongated in one direction. A square mirror would send a lot of the light out of the central region.
3. Is there a danger from micrometeoroids?
A micrometeoroid is a particle smaller than a grain of sand. Most never reach Earth’s surface because they are vaporized by the intense heat generated by the friction of passing through the atmosphere. In space, no blanket of atmosphere protects a spacecraft or a spacewalker.
Webb will be a million miles away from the Earth orbiting what we call the second Lagrange point (L2). Unlike in low Earth orbit, there is not much space debris out there that could damage the exposed mirror.
But we do expect Webb to get impacted by these very tiny micrometeoroids for the duration of the mission, and Webb is designed to accommodate for them.
All of Webb’s systems are designed to survive micrometeoroid impacts.
4. Why does the sunshield have five layers?
Webb has a giant, tennis-court sized sunshield, made of five, very thin layers of an insulating film called Kapton.
Why five? One big, thick sunshield would conduct the heat from the bottom to the top more than would a shield with five layers separated by vacuum. With five layers to the sunshield, each successive one is cooler than the one below.
The heat radiates out from between the layers, and the vacuum between the layers is a very good insulator. From studies done early in the mission development five layers were found to provide sufficient cooling. More layers would provide additional cooling, but would also mean more mass and complexity. We settled on five because it gives us enough cooling with some “margin” or a safety factor, and six or more wouldn’t return any additional benefits.
Fun fact: You could nearly boil water on the hot side of the sunshield, and it is frigid enough on the cold side to freeze nitrogen!
5. What kind of telescope is Webb?
Webb is a reflecting telescope that uses three curved mirrors. Technically, it’s called a three-mirror anastigmat.
6. What happens after launch? How long until there will be data?
In the first hour: About 30 minutes after liftoff, Webb will separate from the Ariane 5 launch vehicle. Shortly after this, we will talk with Webb from the ground to make sure everything is okay after its trip to space.
In the first day: About 10.5 hours after launch, Webb will pass the Moon’s orbit, nearly a quarter of the way to Lagrange Point 2 (L2).
In the first week: We begin the major deployment of Webb. This includes unfolding the sunshield and tensioning the individual membranes, deploying the secondary mirror, and deploying the primary mirror.
In the first month: As the telescope cools in the shade of the sunshield, we turn on the warm electronics and initialize the flight software. As the telescope cools to near its operating temperature, parts of it are warmed with electronic heaters. This prevents condensation as residual water trapped within some of the materials making up the observatory escapes into space.
The first NIRCam image, which will be an out-of-focus image of a crowded star field, will be used to identify each mirror segment with its image of a star in the camera. We will also focus the secondary mirror.
In the third month: We will align the primary mirror segments so that they can work together as a single optical surface. We will also turn on and operate Webb’s mid-infrared instrument (MIRI), a camera and spectrograph that views a wide spectrum of infrared light. By the end of the third month, we will be able to take the first science-quality images. Also by this time, Webb will complete its journey to its L2 orbit position.
In the fourth through the sixth month: We will complete the optimization of the telescope. We will test and calibrate all of the science instruments.
After six months: Webb will begin its science mission and start to conduct routine science operations.
7. Why not assemble it in orbit?
Various scenarios were studied, and assembling in orbit was determined to be unfeasible.
We examined the possibility of in-orbit assembly for Webb. The International Space Station does not have the capability to assemble precision optical structures. Additionally, space debris that resides around the space station could have damaged or contaminated Webb’s optics. Webb’s deployment happens far above low Earth orbit and the debris that is found there.
Finally, if the space station were used as a stopping point for the observatory, we would have needed a second rocket to launch it to its final destination at L2. The observatory would have to be designed with much more mass to withstand this “second launch,” leaving less mass for the mirrors and science instruments.
8. Who is James Webb?
This telescope is named after James E. Webb (1906–1992), our second administrator. Webb is best known for leading Apollo, a series of lunar exploration programs that landed the first humans on the Moon.
However, he also initiated a vigorous space science program that was responsible for more than 75 launches during his tenure, including America’s first interplanetary explorers.
Looking for some more in-depth FAQs? You can find them HERE.
Got basic questions about the James Webb Space Telescope and what amazing things we’ll learn from it? We’ve got your answers right here!
The James Webb Space Telescope, or Webb, is our upcoming infrared space observatory, which will launch in 2021. It will spy the first luminous objects that formed in the universe and shed light on how galaxies evolve, how stars and planetary systems are born, and how life could form on other planets.
1. What is the James Webb Space Telescope?
Our James Webb Space Telescope is a giant space telescope that observes infrared light. Rather than a replacement for the Hubble Space Telescope, it’s a scientific successor that will complement and extend its discoveries.
Being able to see longer wavelengths of light than Hubble and having greatly improved sensitivity will let Webb look further back in time to see the first galaxies that formed in the early universe, and to peer inside dust clouds where stars and planetary systems are forming today.
2. What are the most exciting things we will learn?
We have a lot to learn about how galaxies got supermassive black holes in their centers, and we don’t really know whether the black holes caused the galaxies to form or vice versa.
We can’t see inside dust clouds with high resolution, where stars and planets are being born nearby, but Webb will be able to do just that.
We don’t know how many planetary systems might be hospitable to life, but Webb could tell whether some Earth-like planets have enough water to have oceans.
We don’t know much about dark matter or dark energy, but we expect to learn more about where the dark matter is now, and we hope to learn the history of the acceleration of the universe that we attribute to dark energy.
And then, there are the surprises we can’t imagine!
3. Why is Webb an infrared telescope?
By viewing the universe at infrared wavelengths with such sensitivity, Webb will show us things never before seen by any other telescope. For example, it is only at infrared wavelengths that we can see the first stars and galaxies forming after the Big Bang.
And it is with infrared light that we can see stars and planetary systems forming inside clouds of dust that are opaque to visible light, such as in the above visible and infrared light comparison image of the Carina Nebula.
4. Will Webb take amazing pictures like Hubble? Can Webb see visible light?
YES, Webb will take amazing pictures! We are going to be looking at things we’ve never seen before and looking at things we have seen before in completely new ways.
The beauty and quality of an astronomical image depends on two things: the sharpness and the number of pixels in the camera. On both of these counts, Webb is very similar to, and in many ways better than, Hubble.
Additionally Webb can see orange and red visible light. Webb images will be different, but just as beautiful as Hubble’s. Above, there is another comparison of infrared and visible light Hubble images, this time of the Monkey Head Nebula.
5. What will Webb’s first targets be?
The first targets for Webb will be determined through a process similar to that used for the Hubble Space Telescope and will involve our experts, the European Space Agency (ESA), the Canadian Space Agency (CSA), and scientific community participants.
The first engineering target will come before the first science target and will be used to align the mirror segments and focus the telescope. That will probably be a relatively bright star or possibly a star field.
6. How does Webb compare with Hubble?
Webb is designed to look deeper into space to see the earliest stars and galaxies that formed in the universe and to look deep into nearby dust clouds to study the formation of stars and planets.
In order to do this, Webb has a much larger primary mirror than Hubble (2.5 times larger in diameter, or about 6 times larger in area), giving it more light-gathering power. It also will have infrared instruments with longer wavelength coverage and greatly improved sensitivity than Hubble.
Finally, Webb will operate much farther from Earth, maintaining its extremely cold operating temperature, stable pointing and higher observing efficiency than with the Earth-orbiting Hubble.
7. What will Webb tell us about planets outside our solar system? Will it take photos of these planets?
Webb will be able to tell us the composition of the atmospheres of planets outside our solar system, aka exoplanets. It will observe planetary atmospheres through the transit technique. A transit is when a planet moves across the disc of its parent star.
Webb will also carry coronographs to enable photography of exoplanets (planets outside our solar system) near bright stars (if they are big and bright and far from the star), but they will be only “dots,” not grand panoramas. Coronographs block the bright light of stars, which could hide nearby objects like exoplanets.
Consider how far away exoplanets are from us, and how small they are by comparison to this distance! We didn’t even know what Pluto really looked like until we were able to send an observatory to fly right near it in 2015, and Pluto is in our own solar system!
8. Will we image objects in our own solar system?
Yes! Webb will be able to observe the planets at or beyond the orbit of Mars, satellites, comets, asteroids and objects in the distant, icy Kuiper Belt.
Webb will also monitor the weather of planets and their moons.
Because the telescope and instruments have to be kept cold, Webb’s protective sunshield will block the inner solar system from view. This means that the Sun, Earth, Moon, Mercury, and Venus, and of course Sun-grazing comets and many known near-Earth objects cannot be observed.
9. How far back will Webb see?
Webb will be able to see what the universe looked like around a quarter of a billion years (possibly back to 100 million years) after the Big Bang, when the first stars and galaxies started to form.
10. When will Webb launch and how long is the mission?
Webb will launch in 2021 from French Guiana on a European Space Agency Ariane 5 rocket.
Webb’s mission lifetime after launch is designed to be at least 5-½ years, and could last longer than 10 years. The lifetime is limited by the amount of fuel used for maintaining the orbit, and by the possibility that Webb’s components will degrade over time in the harsh environment of space.
Looking for some more in-depth FAQs? You can find them HERE.
Our James Webb Space Telescope is the most ambitious and complex space science observatory ever built. It will study every phase in the history of our universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar System.
In order to carry out such a daring mission, many innovative and powerful new technologies were developed specifically to enable Webb to achieve its primary mission.
Here are 5 technologies that were developed to help Webb push the boundaries of space exploration and discovery:
Microshutters are basically tiny windows with shutters that each measure 100 by 200 microns, or about the size of a bundle of only a few human hairs.
The microshutter device will record the spectra of light from distant objects (spectroscopy is simply the science of measuring the intensity of light at different wavelengths. The graphical representations of these measurements are called spectra.)
Other spectroscopic instruments have flown in space before but none have had the capability to enable high-resolution observation of up to 100 objects simultaneously, which means much more scientific investigating can get done in less time.
Webb’s backplane is the large structure that holds and supports the big hexagonal mirrors of the telescope, you can think of it as the telescope’s “spine”. The backplane has an important job as it must carry not only the 6.5 m (over 21 foot) diameter primary mirror plus other telescope optics, but also the entire module of scientific instruments. It also needs to be essentially motionless while the mirrors move to see far into deep space. All told, the backplane carries more than 2400kg (2.5 tons) of hardware.
This structure is also designed to provide unprecedented thermal stability performance at temperatures colder than -400°F (-240°C). At these temperatures, the backplane was engineered to be steady down to 32 nanometers, which is 1/10,000 the diameter of a human hair!
One of the Webb Space Telescope’s science goals is to look back through time to when galaxies were first forming. Webb will do this by observing galaxies that are very distant, at over 13 billion light years away from us. To see such far-off and faint objects, Webb needs a large mirror.
Webb’s scientists and engineers determined that a primary mirror 6.5 meters across is what was needed to measure the light from these distant galaxies. Building a mirror this large is challenging, even for use on the ground. Plus, a mirror this large has never been launched into space before!
If the Hubble Space Telescope’s 2.4-meter mirror were scaled to be large enough for Webb, it would be too heavy to launch into orbit. The Webb team had to find new ways to build the mirror so that it would be light enough – only 1/10 of the mass of Hubble’s mirror per unit area – yet very strong.
Read more about how we designed and created Webb’s unique mirrors HERE.
4. Wavefront Sensing and Control
Wavefront sensing and control is a technical term used to describe the subsystem that was required to sense and correct any errors in the telescope’s optics. This is especially necessary because all 18 segments have to work together as a single giant mirror.
The work performed on the telescope optics resulted in a NASA tech spinoff for diagnosing eye conditions and accurate mapping of the eye. This spinoff supports research in cataracts, keratoconus (an eye condition that causes reduced vision), and eye movement – and improvements in the LASIK procedure.
Webb’s primary science comes from infrared light, which is essentially heat energy. To detect the extremely faint heat signals of astronomical objects that are incredibly far away, the telescope itself has to be very cold and stable. This means we not only have to protect Webb from external sources of light and heat (like the Sun and the Earth), but we also have to make all the telescope elements very cold so they don’t emit their own heat energy that could swamp the sensitive instruments. The temperature also must be kept constant so that materials aren’t shrinking and expanding, which would throw off the precise alignment of the optics.
Each of the five layers of the sunshield is incredibly thin. Despite the thin layers, they will keep the cold side of the telescope at around -400°F (-240°C), while the Sun-facing side will be 185°F (85°C). This means you could actually freeze nitrogen on the cold side (not just liquify it), and almost boil water on the hot side. The sunshield gives the telescope the equivalent protection of a sunscreen with SPF 1 million!
When we talk about exploration in far-flung places, you might think of space telescopes taking images of planets outside our solar system, or astronauts floating on the International Space Station.
But did you know our researchers travel to some of Earth’s most inaccessible and dangerous places, too?
Two scientists working with the ICESat-2 mission just finished a trek from the South Pole to latitude 88 south, a journey of about 450 miles. They had to travel during the Antarctic summer – the region’s warmest time, with near-constant sunshine – but the trek was still over solid ice and snow.
The trip lasted 14 days, and was an important part of a process known as calibration and validation. ICESat-2 will launch this fall, and the team was taking extremely precise elevation measurements that will be used to validate those taken by the satellite.
Sometimes our research in Earth’s remote regions helps us understand even farther-flung locations…like other planets.
Geologic features on Mars look very similar to islands and landforms created by volcanoes here on our home planet.
As hot jets of magma make their way to Earth’s surface, they create new rocks and land – a process that may have taken place on Mars and the Moon.
In 2015, our researchers walked on newly cooled lava on the Holuhraun volcano in Iceland to take measurements of the landscape, in order to understand similar processes on other rocky bodies in our solar system.
There may not be flowing lava in the mangrove forests in Gabon, but our researchers have to brave mosquitoes and tree roots that reach up to 15-foot high as they study carbon storage in the vegetation there.
The scientists take some measurements from airplanes, but they also have to gather data from the ground in one our of planet’s most pristine rainforests, climbing over and around roots that can grow taller than people. They use these measurements to create a 3-D map of the ecosystem, which helps them understand how much carbon in stored in the plants.