A sextant is a tool for measuring the angular altitude of a star above the horizon and has helped guide sailors across oceans for centuries. It is now being tested aboard the International Space Station as a potential emergency navigation tool for guiding future spacecraft across the cosmos. The Sextant Navigation investigation will test the use of a hand-held sextant that utilizes star sighting in microgravity.
Massive Martian dust storms have been challenging—and enticing—scientists for decades. Here’s the scoop on Martian dust:
1: Challenging Opportunity
Our Opportunity rover is facing one of the greatest challenges of its 14 ½ year mission on the surface of Mars–a massive dust storm that has turned day to night. Opportunity is currently hunkered down on Mars near the center of a storm bigger than North America and Russia combined. The dust-induced darkness means the solar-powered rover can’t recharge its batteries.
Martian breezes proved a saving grace for the solar-powered Mars rovers in the past, sweeping away accumulated dust and enabling rovers to recharge and get back to science. This is Opportunity in 2014. The image on the left is from January 2014. The image on the right in March 2014.
4: Dusty Disappointment
Back in 1971, scientists were eager for their first orbital views of Mars. But when Mariner 9 arrived in orbit, the Red Planet was engulfed by a global dust storm that hid most of the surface for a month. When the dust settled, geologists got detailed views of the Martian surface, including the first glimpses of ancient riverbeds carved into the dry and dusty landscape.
Scientists know to expect big dust storms on Mars, but the rapid development of the current one is surprising. Decades of Mars observations show a pattern of regional dust storms arising in northern spring and summer. In most Martian years, nearly twice as long as Earth years, the storms dissipate. But we’ve seen global dust storms in 1971, 1977, 1982, 1994, 2001 and 2007. The current storm season could last into 2019.
Once on the Red Planet, InSight will use sophisticated geophysical instruments to delve deep beneath the surface of Mars, detecting the fingerprints of the processes of terrestrial planet formation, as well as measuring the planet’s “vital signs”: Its “pulse” (seismology), “temperature” (heat flow probe), and “reflexes” (precision tracking).
9: Martian Weather Report
One saving grace of dust storms is that they can actually limit the extreme temperature swings experienced on the Martian surface. The same swirling dust that blocks out sunlight also absorbs heat, raising the ambient temperature surrounding Opportunity.
A dust storm in the Sahara can change the skies in Miami and temperatures in the North Atlantic. Earth scientists keep close watch on our home planet’s dust storms, which can darken skies and alter Earth’s climate patterns.
This 45 day mission – which began May 5, 2018 and ends today, June 18 – will help our researchers learn how isolation and close quarters affect individual and group behavior. This study at our Johnson Space Center prepares us for long duration space missions, like a trip to an asteroid or even to Mars.
The Human Research Exploration Analog (HERA) that the crew members will be living in is one compact, science-making house. But unlike in a normal house, these inhabitants won’t go outside for 45 days. Their communication with the rest of planet Earth will also be very limited, and they won’t have any access to internet. So no checking social media, kids!
The only people they will talk with regularly are mission control and each other.
The HERA XVII crew is made up of 2 men and 2 women, selected from the Johnson Space Center Test Subject Screening (TSS) pool. The crew member selection process is based on a number of criteria, including criteria similar to what is used for astronaut selection. The four would-be astronauts are:
What will they be doing?
The crew are going on a simulated journey to an asteroid, a 715-day journey that we compress into 45 days. They will fly their simulated exploration vehicle around the asteroid once they arrive, conducting several site surveys before 2 of the crew members will participate in a series of virtual reality spacewalks.
They will also be participating in a suite of research investigations and will also engage in a wide range of operational and science activities, such as growing and analyzing plants and brine shrimp, maintaining and “operating” an important life support system, exercising on a stationary bicycle or using free weights, and sharpening their skills with a robotic arm simulation.
They work 16 hours a day, Monday through Friday. This includes time for daily planning, conferences, meals and exercise.
Mission: May 5 – June 18, 2018
But beware! While we do all we can to avoid crises during missions, crews need to be able to respond in the event of an emergency. The HERA crew will conduct a couple of emergency scenario simulations, including one that will require them to respond to a decrease in cabin pressure, potentially finding and repairing a leak in their spacecraft.
Throughout the mission, researchers will gather information about living in confinement, teamwork, team cohesion, mood, performance and overall well-being. The crew members will be tracked by numerous devices that each capture different types of data.
Phytoplankton. Have you ever heard of them? At NASA, these
tiny organisms are kind of a big deal.
Biodiversity in the ocean is a delicate, but essential
balance for life on Earth. One way NASA
studies this balance is by observing phytoplankton – microalgae that contain
chlorophyll, require light to grow, and form the base of the marine food chain.
Phytoplankton even have an essential role in an upcoming
This mission is called PACE- “Plankton, Aerosol,
Cloud, ocean Ecosystem.” It will reveal interactions between the ocean and
atmosphere, including how they exchange carbon dioxide and how atmospheric
aerosols might fuel phytoplankton growth in the surface ocean.
What do phytoplankton and clouds have in common? More than
you might think.
PACE will also study aerosols, which are any particles or
droplets suspended in our atmosphere. Humans create aerosols, like soot or car
exhaust, but some phytoplankton release aerosols too.
For example, dust – also an aerosol – can blow into the
ocean, depositing iron that helps phytoplankton grow. These phytoplankton then
release dimethyl sulfide, a gas that turns into an aerosol, which can influence
how clouds form.
Whether the aerosols in our atmosphere come from the ocean
or land, it’s important to know how they are impacting our environment. PACE
will help clear up some of our questions about what is in our air.
The more, the merrier
A healthy ocean supports healthy industries and economies,
contributes to a healthy atmosphere and helps keep plants, animals and humans
healthy and happy. One key to a healthy, balanced ocean is lots of biodiversity.
Biodiversity means having a wide variety of plant and
animal species in an ecosystem. It’s important to have many different species
of phytoplankton, because each species plays a different role in processing
carbon, providing food for tiny animals, and keeping the ocean healthy.
PACE will track the size and movements of phytoplankton
populations from space to help our seas stay diverse and bountiful.
Fisheries: Phytoplankton feed fish feed friends
One simple reason for tracking the ocean’s health is that
fish eat tiny animals that eat phytoplankton, and people eat fish.
Fisheries and aquaculture support about 12 percent of jobs
around the world, including employing more than 3 million people in the United
States. By better understanding our ocean’s health and how it might change in
the future, we can make predictions about impacts to our economies and food
To learn more about phytoplankton, visit our website.
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!
Astronomers James Christy and Robert Harrington weren’t even looking for satellites of Pluto when they discovered Charon in June 1978 at the U.S. Naval Observatory Flagstaff Station in Arizona – only about six miles from where Pluto was discovered at Lowell Observatory. Instead, they were trying to refine Pluto’s orbit around the Sun when sharp-eyed Christy noticed images of Pluto were strangely elongated; a blob seemed to move around Pluto.
The direction of elongation cycled back and forth over 6.39 days―the same as Pluto’s rotation period. Searching through their archives of Pluto images taken years before, Christy then found more cases where Pluto appeared elongated. Additional images confirmed he had discovered the first known moon of Pluto.
2. Forever and Always
Christy proposed the name Charon after the mythological ferryman who carried souls across the river Acheron, one of the five mythical rivers that surrounded Pluto’s underworld. But Christy also chose it for a more personal reason: The first four letters matched the name of his wife, Charlene. (Cue the collective sigh.)
3. Big Little Moon
Charon—the largest of Pluto’s five moons and approximately the size of Texas—is almost half the size of Pluto itself. The little moon is so big that Pluto and Charon are sometimes referred to as a double dwarf planet system. The distance between them is 12,200 miles (19,640 kilometers).
4. A Colorful and Violent History
Many scientists on the New Horizons mission expected Charon to be a monotonous, crater-battered world; instead, they found a landscape covered with mountains, canyons, landslides, surface-color variations and more. High-resolution images of the Pluto-facing hemisphere of Charon, taken by New Horizons as the spacecraft sped through the Pluto system on July 14 and transmitted to Earth on Sept. 21, reveal details of a belt of fractures and canyons just north of the moon’s equator.
5. Grander Canyon
This great canyon system stretches more than 1,000 miles (1,600 kilometers) across the entire face of Charon and likely around onto Charon’s far side. Four times as long as the Grand Canyon, and twice as deep in places, these faults and canyons indicate a titanic geological upheaval in Charon’s past.
6. Officially Official
In April 2018, the International Astronomical Union—the internationally recognized authority for naming celestial bodies and their surface features—approved a dozen names for Charon’s features proposed by our New Horizons mission team. Many of the names focus on the literature and mythology of exploration.
7. Flying Over Charon
This flyover video of Charon was created thanks to images from our New Horizons spacecraft. The “flight” starts with the informally named Mordor (dark) region near Charon’s north pole. Then the camera moves south to a vast chasm, descending to just 40 miles (60 kilometers) above the surface to fly through the canyon system.
8. Strikingly Different Worlds
This composite of enhanced color images of Pluto (lower right) and Charon (upper left), was taken by New Horizons as it passed through the Pluto system on July 14, 2015. This image highlights the striking differences between Pluto and Charon. The color and brightness of both Pluto and Charon have been processed identically to allow direct comparison of their surface properties, and to highlight the similarity between Charon’s polar red terrain and Pluto’s equatorial red terrain.
9. Quality Facetime
Charon neither rises nor sets, but hovers over the same spot on Pluto’s surface, and the same side of Charon always faces Pluto―a phenomenon called mutual tidal locking.
10. Shine On, Charon
Bathed in “Plutoshine,” this image from New Horizons shows the night side of Charon against a star field lit by faint, reflected light from Pluto itself on July 15, 2015.
Read the full version of this week’s ‘10 Things to Know’ article on the web HERE.
In 2016, Fermi showed the Moon is brighter in gamma rays than the Sun. Because the Moon doesn’t have a magnetic field, the surface is constantly pelted from all directions by cosmic rays. These produce gamma rays when they run into other particles, causing a full-Moon gamma-ray glow.
Many galaxies, including our own, have black holes at their centers. In active galaxies, dust and gas fall into and “feed” the black hole, releasing light and heat. In 2015 for the first time, scientists using Fermi data found hints that a galaxy called PG 1553+113 has a years-long gamma-ray emission cycle. They’re not sure what causes this cycle, but one exciting possibility is that the galaxy has a second supermassive black hole that causes periodic changes in what the first is eating.
Gamma-ray bursts are the most luminous explosions in the universe. In 2013, Fermi spotted the brightest burst it’s seen so far in the constellation Leo. In the first three seconds alone, the burst, called GRB 130427A, was brighter than any other burst seen before it. This record has yet to be shattered.
We can directly observe only 20 percent of the matter in the universe. The rest is invisible to telescopes and is called dark matter — and we’re not quite sure what it is. In 2012, Fermi helped place new limits on the properties of dark matter, essentially narrowing the field of possible particles that can describe what dark matter is.
Earth is a place dominated by water, mainly oceans. It’s also a place our researchers study to understand life. Trillions of gallons of water flow freely across the surface of our blue-green planet. Ocean’s vibrant ecosystems impact our lives in many ways.
In celebration of World Oceans Day, here are a few things you might not know about these complex waterways.
1. Why is the ocean blue?
The way light is absorbed and scattered throughout the ocean determines which colors it takes on. Red, orange, yellow,and green light are absorbed quickly beneath the surface, leaving blue light to be scattered and reflected back. This causes us to see various blue and violet hues.
2. Want a good fishing spot?
Follow the phytoplankton! These small plant-like organisms are the beginning of the food web for most of the ocean. As phytoplankton grow and multiply, they are eaten by zooplankton, small fish and other animals. Larger animals then eat the smaller ones. The fishing industry identifies good spots by using ocean color images to locate areas rich in phytoplankton. Phytoplankton, as revealed by ocean color, frequently show scientists where ocean currents provide nutrients for plant growth.
3. The ocean is many colors.
When we look at the ocean from space, we see many different shades of blue. Using instruments that are more sensitive than the human eye, we can measure carefully the fantastic array of colors of the ocean. Different colors may reveal the presence and amount of phytoplankton, sediments and dissolved organic matter.
4. The ocean can be a dark place.
About 70 percent of the planet is ocean, with an average depth of more than 12,400 feet. Given that light doesn’t penetrate much deeper than 330 feet below the water’s surface (in the clearest water), most of our planet is in a perpetual state of darkness. Although dark, this part of the ocean still supports many forms of life, some of which are fed by sinking phytoplankton.
6. In a gallon of average sea water, there is about ½ cup of salt.
The amount of salt varies depending on location. The Atlantic Ocean is saltier than the Pacific Ocean, for instance. Most of the salt in the ocean is the same kind of salt we put on our food: sodium chloride.
7. A single drop of sea water is teeming with life.
It will most likely have millions (yes, millions!) of bacteria and viruses, thousands of phytoplankton cells, and even some fish eggs, baby crabs, and small worms.
8. Where does Earth store freshwater?
Just 3.5 percent of Earth’s water is fresh—that is, with few salts in it. You can find Earth’s freshwater in our lakes, rivers, and streams, but don’t forget groundwater and glaciers. Over 68 percent of Earth’s freshwater is locked up in ice and glaciers. And another 30 percent is in groundwater.
9. Phytoplankton are the “lungs of the ocean”.
Just like forests are considered the “lungs of the earth”, phytoplankton is known for providing the same service in the ocean! They consume carbon dioxide, dissolved in the sunlit portion of the ocean, and produce about half of the world’s oxygen.
Want to learn more about how we study the ocean? Follow @NASAEarth on twitter.
We detected organic molecules at the harsh surface of Mars! And what’s important about this is we now have a lot more certainty that there’s organic molecules preserved at the surface of Mars. We didn’t know that before.
One of the discoveries is we found organic molecules just beneath the surface of Mars in 3 billion-year-old sedimentary rocks.
Second, we’ve found seasonal variations in methane levels in the atmosphere over 3 Mars years (nearly 6 Earth years). These two discoveries increase the chances that the record of habitability and potential life has been preserved on the Red Planet despite extremely harsh conditions on the surface.
Both discoveries were made by our chem lab that rides aboard the Curiosity rover on Mars.
Here’s an image from when we installed the SAM lab on the rover. SAM stands for “Sample Analysis at Mars” and SAM did two things on Mars for this discovery.
One – it tested Martian rocks. After the arm selects a sample of pulverized rock, it heats up that sample and sends that gas into the chamber, where the electron stream breaks up the chemicals so they can be analyzed.
What SAM found are fragments of large organic molecules preserved in ancient rocks which we think come from the bottom of an ancient Martian lake. These organic molecules are made up of carbon and hydrogen, and can include other elements like nitrogen and oxygen. That’s a possible indicator of ancient life…although non-biological processes can make organic molecules, too.
The other action SAM did was ‘sniff’ the air.
When it did that, it detected methane in the air. And for the first time, we saw a repeatable pattern of methane in the Martian atmosphere. The methane peaked in the warm, summer months, and then dropped in the cooler, winter months.
On Earth, 90 percent of methane is produced by biology, so we have to consider the possibility that Martian methane could be produced by life under the surface. But it also could be produced by non-biological sources. Right now, we don’t know, so we need to keep studying the Mars!
One of our upcoming Martian missions is the InSight lander. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to give the Red Planet its first thorough checkup since it formed 4.5 billion years ago. It is the first outer space robotic explorer to study in-depth the “inner space” of Mars: its crust, mantle, and core.
Finding methane in the atmosphere and ancient carbon preserved on the surface gives scientists confidence that our Mars 2020 rover and ESA’s (European Space Agency’s) ExoMars rover will find even more organics, both on the surface and in the shallow subsurface.
Read the full release on today’s announcement HERE.
It’s a scientific conundrum with huge implications for our future: How will our planet react to increasing levels of carbon dioxide in the atmosphere?
Carbon – an essential building block for life – does not stay in one place or take only one form. Carbon, both from natural and human-caused sources, moves within and among the atmosphere, ocean and land.
We’ve been a trailblazer in using space-based and airborne sensors to observe and quantify carbon in the atmosphere and throughout the land and ocean, working with many U.S. and international partners.
Our Orbiting Carbon Observatory-2 (OCO-2) is making unprecedented, accurate global measurements of carbon dioxide levels in the atmosphere and providing unique information on associated natural processes.
ABoVE, our multi-year field campaign in Alaska and Canada is investigating how changes in Arctic ecosystems such as boreal forests in a warming climate result in changes to the balance of carbon moving between the atmosphere and land.
This August we’re embarking on an ocean expedition with the National Science Foundation to the northeast Pacific called EXPORTS that will help scientists develop the capability to better predict how carbon in the ocean moves, which could change as Earth’s climate changes.
ECOSTRESS is slated to launch this summer to the International Space Station to make the first-ever measurements of plant water use and vegetation stress on land – providing key insights into how plants link Earth’s global carbon cycle with its water cycle.
Later this year, ECOSTRESS will be joined on the space station by GEDI, which will use a space borne laser to help estimate how much carbon is locked in forests and how that quantity changes over time.
In early 2019, the OCO-3 instrument is scheduled to launch to the space station to complement OCO-2 observations and allow scientists to probe the daily cycle of carbon dioxide exchange processes over much of the Earth.