Category: satellite

Human Research, Robotic Refueling, Crystallogr…

New
science is headed to the International Space Station aboard
the SpaceX Dragon.

Investigations
on this flight include a test of robotic technology for refueling spacecraft, a
project to map the world’s forests and two student studies inspired by Marvel’s
“Guardians of the Galaxy” series.

Learn
more about the science heading into low-Earth orbit:

The
forest is strong with this one: GEDI studies Earth’s forests in 3D

The Global Ecosystem
Dynamics Investigation (GEDI) is an instrument to measure and map Earth’s
tropical and temperate forests in 3D.

image

The Jedi knights may help
protect a galaxy far, far away, but our GEDI
will help us study and understand forest changes right here on Earth.

Robotic
refueling in space

What’s cooler than cool? Cryogenic propellants,
or ice-cold spacecraft fuel! Our Robotic Refueling Mission 3 (RRM3) will demonstrate technologies for storing and
transferring these special liquids. By establishing ways to replenish this fuel
supply in space, RRM3 could help spacecraft live
longer and journey farther
.

image

The mission’s techniques could even be applied
to potential lunar gas stations at the Moon, or refueling
rockets departing from Mars.

Staying
strong in space

The
Molecular Muscle investigation examines the
molecular causes of muscle abnormalities from spaceflight in C. elgans, a
roundworm and model organism.

This
study could give researchers a better understanding of why muscles deteriorate
in microgravity so they can improve methods to help crew members maintain their
strength in space.

image

Investigation
studies space-grown crystals for protection against radiation

Perfect Crystals is a study to learn more about an
antioxidant protein called manganese superoxide dismutase that protects the
body from the effects of radiation and some harmful chemicals.

The
station’s microgravity environment allows researchers to grow more perfectly
ordered crystals of the proteins. These crystals are brought back to Earth and
studied in detail to learn more about how the manganese superoxide dismutase
works. Understanding how this protein functions may aid researchers in
developing techniques to reduce the threat of radiation exposure to astronauts
as well as prevent and treat some kinds of cancers on Earth.

Satellite
deployment reaching new heights with SlingShot

SlingShot
is a new, cost-effective commercial satellite deployment system that will be
tested for the first time.

image

SlingShot
hardware, two small CubeSats, and a hosted payload will be carried to the
station inside SpaceX’s Dragon capsule and installed on a Cygnus spacecraft
already docked to the orbiting laboratory. Later, Cygnus will depart station
and fly to a pre-determined altitude to release the satellites and interact
with the hosted payload.

Investigation
studies accelerated aging in microgravity

Spaceflight
appears to accelerate aging in both humans and mice. Rodent Research-8 (RR-8) is a study to understand the physiology of
aging and the role it plays on the progression of disease in humans. This
investigation could provide a better understanding of how aging changes the
body, which may lead to new therapies for related conditions experienced by
astronauts in space and people on Earth.

Guardians
of the space station: Student contest flies to orbiting lab

The
MARVEL ‘Guardians of the Galaxy’ Space Station Challenge is a joint project between
the U.S. National Laboratory and Marvel Entertainment featuring two winning
experiments from a contest for American teenage students. For the contest,
students were asked to submit microgravity experiment concepts that related to
the Rocket and Groot characters from Marvel’s “Guardians of the Galaxy” comic
book series.

image

Team
Rocket: Staying Healthy in Space

If
an astronaut suffers a broken tooth or lost filling in space, they need a
reliable and easy way to fix it. This experiment investigates how well a dental
glue activated by ultraviolet light would work in microgravity. Researchers
will evaluate the use of the glue by treating simulated broken teeth and
testing them aboard the station.

Team
Groot: Aeroponic Farming in Microgravity

This
experiment explores an alternative method for watering plants in the absence of
gravity using a misting device to deliver water to the plant roots and an air
pump to blow excess water away. Results from this experiment may enable humans
to grow fruits and vegetables in microgravity, and eliminate a major obstacle
for long-term spaceflight.

These
investigation join hundreds of others currently happening aboard the station.
For more info, follow @ISS_Research!

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com 

Frozen: Ice on Earth and Well Beyond

image

Icy Hearts: A heart-shaped calving front of a glacier in Greenland (left) and Pluto’s frozen plains (right). Credits: NASA/Maria-Jose Viñas and NASA/APL/SwRI

From deep below the soil at Earth’s polar regions to Pluto’s frozen heart, ice exists all over the solar system…and beyond. From right here on our home planet to moons and planets millions of miles away, we’re exploring ice and watching how it changes. Here’s 10 things to know:

1. Earth’s Changing Ice Sheets

image

An Antarctic ice sheet. Credit: NASA

Ice sheets are massive expanses of ice that stay frozen from year to year and cover more than 6 million square miles. On Earth, ice sheets extend across most of Greenland and Antarctica. These two ice sheets contain more than 99 percent of the planet’s freshwater. However, our ice sheets are sensitive to the changing climate.

Data from our GRACE satellites show that the land ice sheets in both Antarctica and Greenland have been losing mass since at least 2002, and the speed at which they’re losing mass is accelerating.

2. Sea Ice at Earth’s Poles

image

Earth’s polar oceans are covered by stretches of ice that freezes and melts with the seasons and moves with the wind and ocean currents. During the autumn and winter, the sea ice grows until it reaches an annual maximum extent, and then melts back to an annual minimum at the end of summer. Sea ice plays a crucial role in regulating climate – it’s much more reflective than the dark ocean water, reflecting up to 70 percent of sunlight back into space; in contrast, the ocean reflects only about 7 percent of the sunlight that reaches it. Sea ice also acts like an insulating blanket on top of the polar oceans, keeping the polar wintertime oceans warm and the atmosphere cool.

Some Arctic sea ice has survived multiple years of summer melt, but our research indicates there’s less and less of this older ice each year. The maximum and minimum extents are shrinking, too. Summertime sea ice in the Arctic Ocean now routinely covers about 30-40 percent less area than it did in the late 1970s, when near-continuous satellite observations began. These changes in sea ice conditions enhance the rate of warming in the Arctic, already in progress as more sunlight is absorbed by the ocean and more heat is put into the atmosphere from the ocean, all of which may ultimately affect global weather patterns.

3. Snow Cover on Earth

image

Snow extends the cryosphere from the poles and into more temperate regions.

Snow and ice cover most of Earth’s polar regions throughout the year, but the coverage at lower latitudes depends on the season and elevation. High-elevation landscapes such as the Tibetan Plateau and the Andes and Rocky Mountains maintain some snow cover almost year-round. In the Northern Hemisphere, snow cover is more variable and extensive than in the Southern Hemisphere.

Snow cover the most reflective surface on Earth and works like sea ice to help cool our climate. As it melts with the seasons, it provides drinking water to communities around the planet.

4. Permafrost on Earth

image

Tundra polygons on Alaska’s North Slope. As permafrost thaws, this area is likely to be a source of atmospheric carbon before 2100. Credit: NASA/JPL-Caltech/Charles Miller

Permafrost is soil that stays frozen solid for at least two years in a row. It occurs in the Arctic, Antarctic and high in the mountains, even in some tropical latitudes. The Arctic’s frozen layer of soil can extend more than 200 feet below the surface. It acts like cold storage for dead organic matter – plants and animals.

In parts of the Arctic, permafrost is thawing, which makes the ground wobbly and unstable and can also release those organic materials from their icy storage. As the permafrost thaws, tiny microbes in the soil wake back up and begin digesting these newly accessible organic materials, releasing carbon dioxide and methane, two greenhouse gases, into the atmosphere.

Two campaigns, CARVE and ABoVE, study Arctic permafrost and its potential effects on the climate as it thaws.

5. Glaciers on the Move

image

Did you know glaciers are constantly moving? The masses of ice act like slow-motion rivers, flowing under their own weight. Glaciers are formed by falling snow that accumulates over time and the slow, steady creep of flowing ice. About 10 percent of land area on Earth is covered with glacial ice, in Greenland, Antarctica and high in mountain ranges; glaciers store much of the world’s freshwater.

Our satellites and airplanes have a bird’s eye view of these glaciers and have watched the ice thin and their flows accelerate, dumping more freshwater ice into the ocean, raising sea level.

6. Pluto’s Icy Heart

image

The nitrogen ice glaciers on Pluto appear to carry an intriguing cargo: numerous, isolated hills that may be fragments of water ice from Pluto’s surrounding uplands. NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Pluto’s most famous feature – that heart! – is stone cold. First spotted by our New Horizons spacecraft in 2015, the heart’s western lobe, officially named Sputnik Planitia, is a deep basin containing three kinds of ices – frozen nitrogen, methane and carbon monoxide.

Models of Pluto’s temperatures show that, due the dwarf planet’s extreme tilt (119 degrees compared to Earth’s 23 degrees), over the course of its 248-year orbit, the latitudes near 30 degrees north and south are the coldest places – far colder than the poles. Ice would have naturally formed around these latitudes, including at the center of Sputnik Planitia.

New Horizons also saw strange ice formations resembling giant knife blades. This “bladed terrain” contains structures as tall as skyscrapers and made almost entirely of methane ice, likely formed as erosion wore away their surfaces, leaving dramatic crests and sharp divides. Similar structures can be found in high-altitude snowfields along Earth’s equator, though on a very different scale.

7. Polar Ice on Mars

image

This image, combining data from two instruments aboard our Mars Global Surveyor, depicts an orbital view of the north polar region of Mars. Credit: NASA/JPL-Caltech/MSSS

Mars has bright polar caps of ice easily visible from telescopes on Earth. A seasonal cover of carbon dioxide ice and snow advances and retreats over the poles during the Martian year, much like snow cover on Earth.

image

This animation shows a side-by-side comparison of CO2 ice at the north (left) and south (right) Martian poles over the course of a typical year (two Earth years). This simulation isn’t based on photos; instead, the data used to create it came from two infrared instruments capable of studying the poles even when they’re in complete darkness. This data were collected by our Mars Reconnaissance Orbiter, and Mars Global Surveyor. Credit: NASA/JPL-Caltech

During summertime in the planet’s north, the remaining northern polar cap is all water ice; the southern cap is water ice as well, but remains covered by a relatively thin layer of carbon dioxide ice even in summertime.

Scientists using radar data from our Mars Reconnaissance Orbiter found a record of the most recent Martian ice age in the planet’s north polar ice cap. Research indicates a glacial period ended there about 400,000 years ago. Understanding seasonal ice behavior on Mars helps scientists refine models of the Red Planet’s past and future climate.

8. Ice Feeds a Ring of Saturn

image

Wispy fingers of bright, icy material reach tens of thousands of kilometers outward from Saturn’s moon Enceladus into the E ring, while the moon’s active south polar jets continue to fire away. Credit: NASA/JPL/Space Science Institute

Saturn’s rings and many of its moons are composed of mostly water ice – and one of its moons is actually creating a ring. Enceladus, an icy Saturnian moon, is covered in “tiger stripes.” These long cracks at Enceladus’ South Pole are venting its liquid ocean into space and creating a cloud of fine ice particles over the moon’s South Pole. Those particles, in turn, form Saturn’s E ring, which spans from about 75,000 miles (120,000 kilometers) to about 260,000 miles (420,000 kilometers) above Saturn’s equator. Our Cassini spacecraft discovered this venting process and took high-resolution images of the system.

image

Jets of icy particles burst from Saturn’s moon Enceladus in this brief movie sequence of four images taken on Nov. 27, 2005. Credit: NASA/JPL/Space Science Institute

9. Ice Rafts on Europa

image

View of a small region of the thin, disrupted, ice crust in the Conamara region of Jupiter’s moon Europa showing the interplay of surface color with ice structures. Credit: NASA/JPL/University of Arizona

The icy surface of Jupiter’s moon Europa is crisscrossed by long fractures. During its flybys of Europa, our Galileo spacecraft observed icy domes and ridges, as well as disrupted terrain including crustal plates that are thought to have broken apart and “rafted” into new positions. An ocean with an estimated depth of 40 to 100 miles (60 to 150 kilometers) is believed to lie below that 10- to 15-mile-thick (15 to 25 km) shell of ice.

The rafts, strange pits and domes suggest that Europa’s surface ice could be slowly turning over due to heat from below. Our Europa Clipper mission, targeted to launch in 2022, will conduct detailed reconnaissance of Europa to see whether the icy moon could harbor conditions suitable for life.

10. Crater Ice on Our Moon

image

The image shows the distribution of surface ice at the Moon’s south pole (left) and north pole (right), detected by our Moon Mineralogy Mapper instrument. Credit: NASA

In the darkest and coldest parts of our Moon, scientists directly observed definitive evidence of water ice. These ice deposits are patchy and could be ancient. Most of the water ice lies inside the shadows of craters near the poles, where the warmest temperatures never reach above -250 degrees Fahrenheit. Because of the very small tilt of the Moon’s rotation axis, sunlight never reaches these regions.

A team of scientists used data from a our instrument on India’s Chandrayaan-1 spacecraft to identify specific signatures that definitively prove the water ice. The Moon Mineralogy Mapper not only picked up the reflective properties we’d expect from ice, but was able to directly measure the distinctive way its molecules absorb infrared light, so it can differentiate between liquid water or vapor and solid ice.

With enough ice sitting at the surface – within the top few millimeters – water would possibly be accessible as a resource for future expeditions to explore and even stay on the Moon, and potentially easier to access than the water detected beneath the Moon’s surface.

11. Bonus: Icy World Beyond Our Solar System!

image

With an estimated temperature of just 50K, OGLE-2005-BLG-390L b is the chilliest exoplanet yet discovered. Pictured here is an artist’s concept. Credit: NASA

OGLE-2005-BLG-390Lb, the icy exoplanet otherwise known as Hoth, orbits a star more than 20,000 light years away and close to the center of our Milky Way galaxy. It’s locked in the deepest of deep freezes, with a surface temperature estimated at minus 364 degrees Fahrenheit (minus 220 Celsius)!

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

The Darkness that Followed Hurricane Michael

Earlier this month, the southeastern United States was struck by Hurricane Michael. After the category 4 storm made landfall on Oct. 10, 2018, Hurricane Michael proceeded to knock out power for at least 2.5 million customers across Florida, Georgia, North Carolina, and Virginia. 

image

In this data visualization, you can clearly see where the lights were taken out in Panama City, Florida. A team of our scientists from Goddard Space Flight Center processed and corrected the raw data to filter out stray light from the Moon, fires, airglow, and any other sources that are not electric lights. They also removed atmosphere interference from dust, haze, and clouds. 

image

In the visualization above, you can see a natural view of the night lights—and a step of the filtering process in an effort to clean up some of the cloud cover. The line through the middle is the path Hurricane Michael took. 

image

Although the damage was severe, tens of thousands of electric power industry workers from all over the country—and even Canada—worked together to restore power to the affected areas. Most of the power was restored by Oct. 15, but some people still need to wait a little longer for the power grids to be rebuilt. Read more here. 

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Counting Down to ICON’s Launch

In October 2018, we’re launching the Ionospheric Connection Explorer, or ICON, to study Earth’s dynamic interface to space.

image

The region of Earth’s atmosphere on the edge of space plays a crucial role in our technology and exploration. This is where many of our satellites — including the International Space Station — orbit, and changing conditions in this region can cause problems for those satellites and disrupt communications signals.

This part of the atmosphere is shaped by a complicated set of factors. From below, regular weather on Earth can propagate upwards and influence this region. From above, electric and magnetic fields and charged particles in space — collectively called space weather — can also trigger changes. ICON’s goal is to better understand this region and how it’s shaped by these outside influences.  

10-mile-per-hour sensitivity

Though the ICON spacecraft zooms around Earth at upwards of 14,000 miles per hour, its wind-measuring instrument, named MIGHTI, can detect changes in wind speed smaller than 10 miles per hour. MIGHTI measures the tiny shifts in color caused by the motion of glowing gases in the upper atmosphere. Then, by making use of the Doppler effect — the same phenomenon that makes an ambulance siren change pitch as it passes you — scientists can figure out the gases’ speed and direction.

image

97-minute orbital period

ICON circles Earth in just over an hour and a half, completing nearly 15 orbits per day. Its orbit is inclined by 27 degrees, so over time, its measurements will completely cover the latitudes scientists are most interested in, near the equator.

image

8 1/3-foot solar panel

ICON doesn’t carry any onboard fuel. Instead, its single solar panel — measuring about 100 inches long and 33 inches wide, a little bit bigger than a standard door — produces power for the spacecraft. In science mode, ICON draws about 209-265 Watts of power.

7 years of teamwork

Now getting ready for launch, the ICON team has been hard at work ever since the idea for the mission was selected for further study in 2011.  

634 pounds

How much does good science weigh? In ICON’s case, about as much as vending machine. The observatory weighs 634 pounds altogether.

5 snapshots per minute from FUV

Because ICON travels so fast, its Far Ultraviolet instrument takes eight snapshots per second of passing structures. This avoids blurring the images and captures the fine detail scientists need. But available bandwidth only allows FUV to send 5 images per minute, so the instrument uses a de-blurring technique called time-delay integration to combine 12 seconds’ worth of data into a single image.

image

Image credit: Mark Belan

4 types of instruments collecting data in tandem

ICON carries four distinct instruments to study Earth’s boundary to space.

  • 2 MIGHTIs (Michelson Interferometer for Global High-resolution Thermospheric Imaging): Built by the Naval Research Laboratory in Washington, D.C., to observe the temperature and speed of the neutral atmosphere. There are two identical MIGHTI instruments onboard ICON.
  • 2 IVMs (Ion Velocity Meter): Built by the University of Texas at Dallas to observe the speed of the charged particle motions, in response to the push of the high-altitude winds and the electric fields they generate. ICON carries two, and they are the mission’s only in situ instruments.  
  • EUV (Extreme Ultra-Violet instrument): Built by the University of California, Berkeley to capture images of oxygen glowing in the upper atmosphere, in order to measure the height and density of the daytime ionosphere.
  • FUV (Far Ultra-Violet instrument): Built by UC Berkeley to capture images of the upper atmosphere in the far ultraviolet light range. At night, FUV measures the density of the ionosphere, tracking how it responds to weather in the lower atmosphere. During the day, FUV measures changes in the chemistry of the upper atmosphere — the source for the charged gases found higher up in space.

360 miles above Earth

ICON orbits about 360 miles above Earth, near the upper reaches of the ionosphere — the region of Earth’s atmosphere populated by electrically charged particles. From this vantage point, ICON combines remote measurements looking down along with direct measurements of the material flowing around it to connect changes throughout this region.

2 missions working together

NASA’s GOLD mission — short for Global-scale Observations of the Limb and Disk — launched aboard a commercial communications satellite on Jan. 25, 2018. From its vantage point in geostationary orbit over Brazil, GOLD gets a full-disk view of the same region of space that ICON studies, helping scientists connect the big picture with the details.

1 gigabit of data per day

Together, ICON’s instruments produce and downlink about 1 gigabit of data per day — about 125 megabytes. This adds up to about 1 gigabyte per week. ICON produces 10 different data products, ranging from measurements of wind speeds and ionospheric density to more complex models, that will help scientists shed new light on this ever-changing region.

ICON’s launch is scheduled for 4 a.m. EDT on Oct. 26, and NASA TV coverage begins at 3:45 a.m. Stay tuned on Twitter and Facebook for the latest on ICON. 

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

NASA’s New Planet Hunter Reveals a Sky Full of…

image

NASA’s newest planet-hunting satellite — the Transiting
Exoplanet Survey Satellite, or TESS for short
— has just released its first science image using all
of its cameras to capture a huge swath of the sky! TESS is NASA’s next step in the
search for planets outside our solar system, called exoplanets.

image

This spectacular image, the first released
using all four of TESS’ cameras, shows the satellite’s full field of view. It
captures parts of a dozen constellations, from Capricornus
(the Sea Goat) to Pictor
(the Painter’s Easel) — though it might be hard to find familiar constellations
among all these stars! The image even includes the Large and Small Magellanic
Clouds, our galaxy’s two largest companion galaxies.

The science community calls this image “first
light,” but don’t let that fool you — TESS has been seeing light since it
launched in April. A first light image like this is released to show off the
first science-quality image taken after a mission starts collecting science
data, highlighting a spacecraft’s capabilities.

image

TESS has been busy since it launched from NASA’s Kennedy Space Center in Cape Canaveral, Florida. First TESS needed to get into position, which required a push from the Moon.

After nearly a month in space, the satellite
passed about 5,000 miles from the Moon, whose gravity gave it the boost it needed to get into a special orbit
that will keep it stable and maximize its view of the sky.

image

During those first few weeks, we also got a
sneak peek of the sky through one of TESS’s four cameras. This test image
captured over 200,000 stars in just two seconds! The spacecraft was pointed
toward the constellation Centaurus when it snapped this picture. The bright
star Beta
Centauri
is visible at the lower left edge, and the edge
of the Coalsack
Nebula
is in the right upper corner.

image

After settling into orbit, scientists ran a
number of checks on TESS, including testing its ability to collect a set of
stable images over a prolonged period of time. TESS not only proved its ability
to perform this task, it also got a surprise! A comet named C/2018 N1 passed through TESS’s cameras
for about 17 hours in July.

The images show a treasure
trove of cosmic curiosities
. There are some stars whose
brightness changes over time and asteroids visible as small moving white dots.
You can even see an arc of stray light from Mars, which is located outside the
image, moving across the screen.

image

Now that TESS has settled into orbit and has
been thoroughly tested, it’s digging into its main mission of finding planets around other stars.
How will it spot something as tiny and faint as a planet trillions of miles
away? The trick is to look at the star!

So far, most
of the exoplanets we’ve found
were detected by looking
for tiny dips in the brightness of their host stars. These dips are caused by
the planet passing between us and its star – an event called a transit. Over
its first two years, TESS will stare at 200,000 of the nearest and brightest stars
in the sky to look for transits to identify stars with planets.

image

TESS will be building on the legacy of NASA’s Kepler spacecraft, which also used
transits to find exoplanets. TESS’s target stars are about 10 times closer than
Kepler’s, so they’ll tend to be brighter. Because they’re closer and brighter,
TESS’s target stars will be ideal candidates for follow-up studies with current
and future observatories.

image

TESS is challenging over 200,000 of our
stellar neighbors to a staring contest! Who knows what new amazing planets
we’ll find?

The
TESS mission is led by MIT
and came together with the help of many
different partners
. You can keep up
with the latest from the TESS mission by following mission updates.

Make
sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Did somebody say space laser?

We’re set to launch ICESat-2, our most advanced laser instrument of its kind, into orbit around Earth on Sept. 15. The Ice, Cloud and land Elevation Satellite-2 will make critical observations of how ice sheets, glaciers and sea ice are changing over time, helping us better understand how those changes affect people where they live. Here’s 10 numbers to know about this mission:

image

One Space Laser

There’s only one scientific instrument on ICESat-2, but it’s a marvel. The Advanced Topographic Laser Altimeter System, or ATLAS, measures height by precisely timing how long it takes individual photons of light from a laser to leave the satellite, bounce off Earth, and return to ICESat-2. Hundreds of people at our Goddard Space Flight Center worked to build this smart-car-sized instrument to exacting requirements so that scientists can measure minute changes in our planet’s ice.

image

Sea ice is seen in front of Apusiaajik Glacier in Greenland. Credit: NASA/JPL-Caltech/Jim Round

Two Types of Ice

Not all ice is the same. Land ice, like the ice sheets in Greenland and Antarctica, or glaciers dotting the Himalayas, builds up as snow falls over centuries and forms compacted layers. When it melts, it can flow into the ocean and raise sea level. Sea ice, on the other hand, forms when ocean water freezes. It can last for years, or a single winter. When sea ice disappears, there is no effect on sea level (think of a melting ice cube in your drink), but it can change climate and weather patterns far beyond the poles.

image

3-Dimensional Earth

ICESat-2 will measure elevation to see how much glaciers, sea ice and ice sheets are rising or falling. Our fleet of satellites collect detailed images of our planet that show changes to features like ice sheets and forests, and with ICESat-2’s data, scientists can add the third dimension – height – to those portraits of Earth.

image

Four Seasons, Four Measurements

ICESat-2’s orbit will make 1,387 unique ground tracks around Earth in 91 days – and then start the same ground pattern again at the beginning. This allows the satellite to measure the same ground tracks four times a year and scientists to see how glaciers and other frozen features change with the seasons – including over winter.

image

532 Nanometer Wavelength

The ATLAS instrument will measure ice with a laser that shines at 532 nanometers – a bright green on the visible spectrum. When these laser photons return to the satellite, they pass through a series of filters that block any light that’s not exactly at this wavelength. This helps the instrument from being swamped with all the other shades of sunlight naturally reflected from Earth.

image

Six Laser Beams

While the first ICESat satellite (2003-2009) measured ice with a single laser beam, ICESat-2 splits its laser light into six beams – the better to cover more ground (or ice). The arrangement of the beams into three pairs will also allow scientists to assess the slope of the surface they’re measuring.

image

Seven Kilometers Per Second

ICESat-2 will zoom above the planet at 7 km per second (4.3 miles per second), completing an orbit around Earth in 90 minutes. The orbits have been set to converge at the 88-degree latitude lines around the poles, to focus the data coverage in the region where scientists expect to see the most change.

image

800-Picosecond Precision

All of those height measurements come from timing the individual laser photons on their 600-mile roundtrip between the satellite and Earth’s surface – a journey that is timed to within 800 picoseconds. That’s a precision of nearly a billionth of a second. Our engineers had to custom build a stopwatch-like device, because no existing timers fit the strict requirements.

image

Nine Years of Operation IceBridge

As ICESat-2 measures the poles, it adds to our record of ice heights that started with the first ICESat and continued with Operation IceBridge, an airborne mission that has been flying over the Arctic and Antarctic for nine years. The campaign, which bridges the gap between the two satellite missions, has flown since 2009, taking height measurements and documenting the changing ice.

image

10,000 Pulses a Second

ICESat-2’s laser will fire 10,000 times in one second. The original ICESat fired 40 times a second. More pulses mean more height data. If ICESat-2 flew over a football field, it would take 130 measurements between end zones; its predecessor, on the other hand, would have taken one measurement in each end zone.

image

And One Bonus Number: 300 Trillion

Each laser pulse ICESat-2 fires contains about 300 trillion photons! Again, the laser instrument is so precise that it can time how long it takes individual photons to return to the satellite to within one billionth of a second. 

Learn more about ICESat-2: https://www.nasa.gov/icesat-2

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Glacier Turns into a ‘Snow Swamp’

In just four days this summer, miles of snow melted from
Lowell Glacier in Canada. Mauri Pelto, a glaciologist at Nichols College,
called the area of water-saturated snow a “snow swamp.”

image

These false-color images
show the rapid snow melt in Kluane National Park in the Yukon Territory. The
first image was taken on July 22, 2018, by the European Space Agency’s Sentinel-2;
the next image was acquired on July 26, 2018, by the Landsat 8 satellite.

Ice is shown as light blue, while meltwater is dark blue. On
July 26, the slush covered more than 25 square miles (40 square km).

During those four days, daily temperatures 40 miles (60 km)
northeast of the glacier reached 84 degrees Fahrenheit (29 degrees Celsius) —
much higher than normal for the region in July.

Read more: https://go.nasa.gov/2Q9JSeO

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Last Glacier Standing in Venezuela

In 1910, glaciers covered at least 4 square miles (10 square
km) of the mountainous region of northwestern Venezuela. Today, less than one
percent of that ice remains, and all of it is locked up in one glacier. The
ongoing retreat of Humboldt Glacier—Venezuela’s last patch of perennial
ice—means that the country could soon be glacier-free.

image

The glacier is in the highest part of the Andes Mountains,
on a slope at nearly 16,000 feet. A cold
and snowy climate at high elevations is key for glaciers to exist in the
tropics. Most of Earth’s tropical glaciers are found in the Andes, which runs
through Venezuela, Colombia, Ecuador, Peru and Bolivia. But warming air temperatures
have contributed to their decline, including Humboldt Glacier.

The relatively recent changes to Humboldt are evident in
these images, acquired on Jan. 20, 1988, by the
United States Geological Survey’s Landsat 5
and on Jan. 6, 2015,
by Landsat 8. The images are false-color to better differentiate between areas
of snow and ice (blue), land (brown) and vegetation (green).

Scientists are trying to understand how long Humboldt will remain.
One said: “Let’s call it no more than 10 to 20 years.”

Read more: https://go.nasa.gov/2NuYcg6

Take a deep breath. Even if the air looks clea…

Take a deep breath. Even if the air looks clear, it is nearly certain that you will inhale millions of solid particles and liquid droplets. These ubiquitous specks of matter are known as aerosols, and they can be found in the air over oceans, deserts, mountains, forests, ice, and every ecosystem in between.

If you have ever watched smoke billowing from a wildfire, ash erupting from a volcano, or dust blowing in the wind, you have seen aerosols. Satellites like Terra, Aqua, Aura, and Suomi NPP “see” them as well, though they offer a completely different perspective from hundreds of kilometers above Earth’s surface. A version of one of our models called the Goddard Earth Observing System Forward Processing (GEOS FP) offers a similarly expansive view of the mishmash of particles that dance and swirl through the atmosphere.

The visualization above highlights GEOS FP model output for aerosols on August 23, 2018. On that day, huge plumes of smoke drifted over North America and Africa, three different tropical cyclones churned in the Pacific Ocean, and large clouds of dust blew over deserts in Africa and Asia. The storms are visible within giant swirls of sea salt aerosol(blue), which winds loft into the air as part of sea spray. Black carbon particles (red) are among the particles emitted by fires; vehicle and factory emissions are another common source. Particles the model classified as dust are shown in purple. The visualization includes a layer of night light data collected by the day-night band of the Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi NPP that shows the locations of towns and cities.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

In Conversation with the Sun: Parker Solar Pro…

Our Sun powers life on Earth. It defines our days, nourishes our
crops and even fuels our electrical grids. In our pursuit of knowledge
about the universe, we’ve learned so much about the Sun, but in many ways we’re
still in conversation with it, curious about its mysteries.

image

Parker Solar
Probe
will advance this conversation, flying
through the Sun’s atmosphere as close as 3.8 million miles from our star’s
surface, more than seven times closer to it than any previous spacecraft. If
space were a football field, with Earth at one end and the Sun at the other,
Parker would be at the four-yard line, just steps away from the Sun! This
journey will revolutionize our understanding of the Sun, its surface and solar
winds.

image

Supporting Parker on its journey to the
Sun are our communications networks. Three networks, the Near Earth Network,
the Space
Network
and the Deep Space Network, provide our
spacecraft with their communications, delivering their data to mission
operations centers. Their services ensure that missions like Parker have
communications support from launch through the mission.

image

For Parker’s launch
on Aug. 12, the Delta IV Heavy rocket that sent Parker skyward relied on the Space
Network. A team at Goddard Space Flight Center’s Networks Integration Center
monitored the launch, ensuring that we maintained tracking and communications
data between the rocket and the ground. This data is vital, allowing engineers
to make certain that Parker stays on the right path towards its orbit around
the Sun.

image

The Space Network’s constellation of Tracking and Data
Relay Satellites
(TDRS) enabled constant communications coverage for
the rocket as Parker made its way out of Earth’s atmosphere. These satellites
fly in geosynchronous orbit, circling Earth in step with its rotation, relaying
data from spacecraft at lower altitudes to the ground. The network’s three collections
of TDRS over the Atlantic, Pacific and Indian oceans provide enough coverage
for continuous communications for satellites in low-Earth orbit.

image

The Near Earth Network’s Launch
Communications Segment tracked early stages of Parker’s launch, testing our brand
new ground stations’ ability to provide crucial information about the rocket’s
initial velocity (speed) and trajectory (path). When fully operational, it will
support launches from the Kennedy spaceport, including upcoming Orion
missions. The Launch Communications Segment’s three ground stations are located
at Kennedy Space Center; Ponce De Leon, Florida; and Bermuda. 

image

When Parker separated from the Delta IV
Heavy, the Deep Space Network took over. Antennas up to 230 feet in diameter at
ground stations in California, Australia and Spain are supporting Parker for
its 24 orbits around the Sun and the seven Venus flybys that gradually shrink
its orbit, bringing it closer and closer to the Sun. The Deep Space Network is
delivering data to mission operations centers and will continue to do so as
long as Parker is operational.

Near the
Sun, radio interference and the heat load on the spacecraft’s antenna makes
communicating with Parker a challenge that we must plan for. Parker has three
distinct communications phases, each corresponding to a different part of its
orbit.

When Parker comes closest to the Sun, the
spacecraft will emit a beacon tone that tells engineers on the ground about its
health and status, but there will be very little opportunity to command the
spacecraft and downlink data. High data rate transmission will only occur
during a portion of Parker’s orbit, far from the Sun. The rest of the time,
Parker will be in cruise mode, taking measurements and being commanded through
a low data rate connection with Earth.

image

Communications infrastructure is vital to
any mission. As Parker journeys ever closer to the center of our solar system,
each byte of downlinked data will provide new insight into our Sun. It’s a
mission that continues a conversation between us and our star that has lasted many
millions of years and will continue for many millions more.

For more information about NASA’s mission
to touch the Sun: https://www.nasa.gov/content/goddard/parker-solar-probe

For more information about our satellite
communications check out: http://nasa.gov/SCaN


Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.