Category: solar system

How Do You Like Your Turkey? Home-Cooked or Ro…

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It’s Thanksgiving, which means that you’re probably thinking about food right now. And here at NASA, we have to think about food very seriously when we explore space!

Astronauts Need to Eat, Too!

Like for you on Earth, nutrition plays a key role in maintaining the health and optimal performance of the astronauts. The Space Food Systems team is required to meet the nutritional needs of each crew member while adhering to the requirements of limited storage space, limited preparation options, and the difficulties of eating without gravity. 

Good food is necessary being comfortable on a mission a long way from home — especially for crewmembers who are on board for many months at a time. It’s important that the astronauts like the food they’re eating everyday, even given the preparation constraints!

Astronaut Food Has Not Always Been Appetizing

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The early space programs were groundbreaking in a lot of ways — but not when it came to food. Like today, crumbs had to be prevented from scattering in microgravity and interfering with the instruments. Mercury astronauts had to endure bite-sized cubes, freeze-dried powders, and semi-liquids stuffed into aluminum tubes. The freeze-dried food were hard to rehydrate, squeezing the tubes was understandable unappetizing, and the food was generally considered to be, like spaceflight, a test of endurance.

However, over the years, packaging improved, which in turn enhanced food quality and choices. The Apollo astronauts were the first to have hot water, which made rehydrating foods easier and improved the food’s taste. And even the Space Shuttle astronauts had opportunities to design their own menus and choose foods commercially available on grocery store shelves. 

 The Wonders of Modern Space Food

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Nowadays, astronauts on the International Space Station have the opportunity to sample a variety of foods and beverages prepared by the Space Food Systems team and decide which ones they prefer. They can add water to rehydratable products or eat products that are ready to eat off the shelf.

All the cooking and preparation has been done for them ahead of time because 1) they don’t have room for a kitchen to cook on the space station 2) they don’t have time to cook! The crewmembers are extremely occupied with station maintenance as well as scientific research on board, so meal times have to be streamlined as much as possible. 

Instead of going grocery shopping, bulk overwrap bags (BOBs!) are packed into cargo transfer bags for delivery to the space station. Meal based packaging allows the astronauts to have entrees, side dishes, snacks, and desserts to choose from. 

Taste in Space

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The perception of taste changes in space. In microgravity, astronauts experience a fluid shift in their bodies, so the sensation is similar to eating with a headcold. The taste is muted so crewmembers prefer spicy foods or food with condiments to enhance the flavor. 

We Can’t Buy Groceries, But We Can Grow Food!

Growing plants aboard the space station provides a unique opportunity to study how plants adapt to microgravity. Plants may serve as a food source for long term missions, so it’s critical to understand how spaceflight affects plant growth. Plus, having fresh food available in space can have a positive impact on astronauts’ moods!

Since 2002, the Lada greenhouse has been used to perform almost continuous plant growth experiments on the station. We have grown a vast variety of plants, including thale cress, swiss chard, cabbage, lettuce, and mizuna. 

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And in 2015, Expedition 44 members became the first American astronauts to eat plants grown in space when they munched on their harvest of Red Romaine. 

Earthlings Can Eat Space Food, Too

To give you a clear idea of how diverse the selection is for astronauts on board the space station, two earthlings gave the astronaut menu a try for a full week. Besides mentioning once that hot sauce was needed, they fared pretty well! (The shrimp cocktail was a favorite.)

Space Technology for Food on Earth

Not only has our space food improved, but so has our ability measure food production on Earth. Weather that is too dry, too wet, too hot, or too cool can strongly affect a farmer’s ability to grow crops. We collaborated with the United States Agency for International Development to create a system for crop yield prediction based on satellite data: the GEOGLAM Crop Monitor for Early Warning.

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This map measures the health, or “greenness” of vegetation based on how much red or near-infrared light the leaves reflect. Healthy vegetation reflects more infrared light and less visible light than stressed vegetation. As you can see from the map, a severe drought spread across southern Mexico to Panama in June to August of this year. 

The Crop Monitor compiles different types of crop condition indicators — such as temperature, precipitation, and soil moisture — and shares them with 14 national and international partners to inform relief efforts.

Thanksgiving in Space 

Space food has certainly come a long way from semi-liquids squeezed into aluminum tubes! This year, Expedition 57 crewmembers Commander Alexander Gerst and Flight Engineer Serena M. Auñón-Chancellor are looking forward to enjoying a Thanksgiving meal that probably sounds pretty familiar to you: turkey, stuffing, candied yams, and even spicy pound cakes!

Hungry for More?

If you can’t get enough of space food, tune into this episode of “Houston, We Have a Podcast” and explore the delicious science of astronaut mealtime with Takiyah Sirmons. 

And whether you’re eating like a king or an astronaut, we wish everybody a happy and safe Thanksgiving!

I never get tired of this photo, and will post…

I never get tired of this photo, and will post it again and again.  In the words of Carl Sagan…a pale blue dot.

Take a moment to contemplate our home in the grand scheme of the universe.  In the middle of petty squabbles and power grabs, in the end, we are adrift on our cosmic journey.  We need to take better care of our “spaceship”. 

And for those who do not care or would not hesitate to screw our home over to make some money, I’d love to banish you to Venus.

Things That Go Bump in the Gamma Rays

Some people watch scary movies because they like being startled. A bad guy jumps out from around a corner! A monster emerges from the shadows! Scientists experience surprises all the time, but they’re usually more excited than scared. Sometimes theories foreshadow new findings — like when there’s a dramatic swell in the movie soundtrack — but often, discoveries are truly unexpected. 

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Scientists working with the Fermi Gamma-Ray Space Telescope have been jumping to study mysterious bumps in the gamma rays for a decade now. Gamma rays are the highest-energy form of light. Invisible to human eyes, they’re created by some of the most powerful and unusual events and objects in the universe. In celebration of Halloween, here are a few spooky gamma-ray findings from Fermi’s catalog.

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Stellar Graveyards

If you were to walk through a cemetery at night, you’d expect to trip over headstones or grave markers. Maybe you’d worry about running into a ghost. If you could explore the stellar gravesite created when a star explodes as a supernova, you’d find a cloud of debris expanding into interstellar space. Some of the chemical elements in that debris, like gold and platinum, go on to create new stars and planets! Fermi found that supernova remnants IC 443 and W44 also accelerate mysterious cosmic rays, high-energy particles moving at nearly the speed of light. As the shockwave of the supernova expands, particles escape its magnetic field and interact with non-cosmic-ray particles to produce gamma rays. 

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Ghost Particles

But the sources of cosmic rays aren’t the only particle mysteries Fermi studies. Just this July, Fermi teamed up with the IceCube Neutrino Observatory in Antarctica to discover the first source of neutrinos outside our galactic neighborhood. Neutrinos are particles that weigh almost nothing and rarely interact with anything. Around a trillion of them pass through you every second, ghost-like, without you noticing and then continue on their way. (But don’t worry, like a friendly ghost, they don’t harm you!) Fermi traced the neutrino IceCube detected back to a supermassive black hole in a distant galaxy. By the time it reached Earth, it had traveled for 3.7 billion years at almost the speed of light!

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Black Widow Pulsars

Black widows and redbacks are species of spiders with a reputation for devouring their partners. Astronomers have discovered two types of star systems that behave in a similar way. Sometimes when a star explodes as a supernova, it collapses back into a rapidly spinning, incredibly dense star called a pulsar. If there’s a lighter star nearby, it can get stuck in a close orbit with the pulsar, which blasts it with gamma rays, magnetic fields and intense winds of energetic particles. All these combine to blow clouds of material off the low-mass star. Eventually, the pulsar can eat away at its companion entirely.

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Dark Matter

What’s spookier than a good unsolved mystery? Dark matter is a little-understood substance that makes up most of the matter in the universe. The stuff that we can see — stars, people, haunted houses, candy — is made up of normal matter. But our surveys of the cosmos tell us there’s not enough normal matter to keep things working the way they do. There must be another type of matter out there holding everything together. One of Fermi’s jobs is to help scientists narrow down the search for dark matter. Last year, researchers noticed that most of the gamma rays coming from the Andromeda galaxy are confined to its center instead of being spread throughout. One possible explanation is that accumulated dark matter at the center of the galaxy is emitting gamma rays!

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Fermi has helped us learn a lot about the gamma-ray universe over the last 10 years. Learn more about its accomplishments and the other mysteries it’s working to solve. What other surprises are waiting out among the stars?

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10 Ways to Celebrate Halloween with NASA

There’s a whole universe of mysteries out there to put some fun—and maybe a touch of fright—into your All Hallows Eve festivities. Here are a few:

1. Universe of Monsters

Mythical monsters of Earth have a tough time of it. Vampires don’t do sunlight. Werewolves must wait for a full Moon to howl. Now, thanks to powerful space telescopes, some careful looking and a lot of whimsy, NASA scientists have found suitable homes for the most terrifying Halloween monsters.

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2. Be a Spacecraft

No costume. No problem. NASA Blueshift offers some handy tips on transforming yourself into a powerful space telescope before hitting the sidewalk to trick-or-treat.

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3. Robot Pumpkins

At Halloween, engineers at NASA’s Jet Propulsion Laboratory craft dramatic creations that have as much in common with standard jack-o’-lanterns as paper airplanes do with NASA spacecraft. The unofficial pumpkin carving contest gives engineers a chance to flex their creative muscles and bond as a team. The rules are simple: no planning, carving or competing during work hours.

The results? See for yourself!

Can’t wait to see this year’s creations? Do it yourself!

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4. Skull Comet

Scientists think a large space rock that zipped past Earth on Halloween in 2015 was most likely a dead comet or an asteroid that, fittingly, bore an eerie resemblance to a skull.

“The object might be a dead comet, but in the (radar) images it appears to have donned a skull costume for its Halloween flyby,” said NASA scientist Kelly Fast,

As with a lot of spooky things, the asteroid looked a lot less scary upon closer inspection.

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5. Spooky Sun

Not to be outdone, the Sun—our star—has been known to put on a scary face.

In this October 2014 Solar Dynamic Observatory image, active regions on the Sun combined to look something like a jack-o-lantern’s face.

The active regions appear brighter because those are areas that emit more light and energy—markers of an intense and complex set of magnetic fields hovering in the Sun’s atmosphere, the corona. This image blends together two sets of wavelengths at 171 and 193 angstroms, typically colorized in gold and yellow, to create a particularly Halloween-like appearance.

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6. Halloween on a Mission

Halloween held a special significance for NASA’s Cassini mission, which launched in October 1997. The team held its own elaborate pumpkin carving competitions for many years. The mission also shared whimsical Halloween greetingswith its home planet.

Cassini ended its extended mission at Saturn in 2017.

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7. The Ghost of Cassiopeia

The brightest stars embedded in nebulae throughout our galaxy pour out a torrent of radiation that eats into vast clouds of hydrogen gas – the raw material for building new stars. This etching process sculpts a fantasy landscape where human imagination can see all kinds of shapes and figures. This nebula in the constellation of Cassiopeia has flowing veils of gas and dust that have earned it the nickname “Ghost Nebula.”

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8. They’re Everywhere

Turns out the human mind—including space scientists and engineers among us—find spooky shapes in many places.

This infrared view of the Helix Nebula reminded astronomers of a zombie eyeball.

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9. What Do You See?

The Oct. 26 Earth Observatory’s Puzzler feature offers a spooky shape for your consideration. What is it and what does it look like? You tell us.

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10. Space Candy

The trick-or-treat tradition is still—so far—pretty much confined to Earth. But thanks to the men and women who have been living aboard the International Space Station for more than 17 years, we have a preview of what a future space-based trick-or-treater’s Halloween candy haul would look like in microgravity.

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Bonus: 11. Want More?

Our education team offers a bunch more Halloween activities, including space-themed pumpkin stencils, costume tips and even some mysteries to solve like a scientist or engineer.

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Frozen: Ice on Earth and Well Beyond

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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

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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

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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

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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

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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

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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

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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

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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.

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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

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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.

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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

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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

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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!

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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)!

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We’re Landing a Rover on Mars in 2020…But How …

In 2020, we will launch our next Mars rover. It will journey more than 33 million miles to the Red Planet where it will land, explore and search for signs of ancient microbial life. But how do we pinpoint the perfect location to complete this science…when we’re a million miles away on Earth?

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We utilize data sent to us by spacecraft on and orbiting Mars. That includes spacecraft that have recorded data in the past.

This week, hundreds of scientists and Mars enthusiasts are gathering to deliberate the four remaining options for where we’re going to land the Mars 2020 rover on the Red Planet.

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The landing site for Mars 2020 is of great interest to the planetary community because, among the rover’s new science gear for surface exploration, it carries a sample system that will collect rock and soil samples and set them aside in a “cache” on the surface of Mars. A future mission could potentially return these samples to Earth. The next Mars landing, after Mars 2020, could very well be a vehicle which would retrieve these Mars 2020 samples.

Here’s an overview of the potential landing sites for our Mars 2020 rover…

Northeast Syrtis

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This area was once warmed by volcanic activity. Underground heat sources made hot springs flow and surface ice melt. Microbes could have flourished here in liquid water that was in contact with minerals. The layered terrain there holds a rich record of interactions between water and minerals over successive periods of early Mars history.

Jezero Crater

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This area tells a story of the on-again, off-again nature of the wet past of Mars. Water filled and drained away from the crater on at least two occasions. More than 3.5 billion years ago, river channels spilled over the crater wall and created a lake. Scientists see evidence that water carried clay minerals from the surrounding area into the crater after the lake dried up. Conceivably, microbial life could have lived in Jezero during one or more of these wet times. If so, signs of their remains might be found in lakebed sediments.

Columbia Hills

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At this site, mineral springs once bubbled up from the rocks. The discovery that hot springs flowed here was a major achievement of the Mars Exploration Rover, Spirit. The rover’s discovery was an especially welcome surprise because Spirit had not found signs of water anywhere else in the 100-mile-wide Gusev Crater. After the rover stopped working in 2010, studies of its older data records showed evidence that past floods may have formed a shallow lake in Gusev.

Midway

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Candidate landing sites Jezero and Northeast Syrtis are approximately 37 km apart…which is close enough for regional geologic similarities to be present, but probably too far for the Mars 2020 rover to travel. This midway point allows exploration of areas of both landing sites.

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How Will We Select a Site?

The team is gathered this week for the fourth time to discuss these locations. It’ll be the final workshop in a series designed to ensure we receive the best and most diverse range of information and opinion from the scientific community before deciding where to send our newest rover.

The Mars 2020 mission is tasked with not only seeking signs of ancient habitable conditions on Mars, but also searching for signs of past microbial life itself. So how do we choose a landing site that will optimize these goals? Since InSight is stationary and needs a flat surface to deploy its instruments, we’re basically looking for a flat, parking lot area on Mars to land the spacecraft.

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The first workshop started with about 30 candidate landing sites and was narrowed down to eight locations to evaluate further. At the end of the third workshop in February 2017, there were only three sites on the radar as potential landing locations…

…but in the ensuing months, a proposal came forward for a landing site that is in between Jezero and Northeast Syrtis – The Midway site. Since our goal is to get to the right site that provides the maximum science, this fourth site was viewed as worthy of being included in the discussions.

Now, with four sites remaining, champions for each option will take their turn at the podium, presenting and defending their favorite spot on the Red Planet.

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On the final day, after all presentations have concluded, workshop participants will weigh the pros and cons of each site. The results of these deliberations will be provided to the Mars 2020 Team, which will incorporate them into a recommendation to NASA Headquarters. A final selection will be made and will likely be announced by the end of the year.

To get more information about the workshop, visit: https://marsnext.jpl.nasa.gov/workshops/wkshp_2018_10.cfm

Learn more about our Mars 2020 rover HERE.

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What Can We Learn from the Universe’s Baby Pic…

If you look at your baby photos, you might see hints of the person you are today — a certain look in the eyes, maybe the hint of your future nose or ears. In the same way, scientists examine the universe’s “baby picture” for clues about how it grew into the cosmos we know now. This baby photo is the cosmic microwave background (CMB), a faint glow that permeates the universe in all directions.

In late September, NASA plans to launch a balloon-based astronomical observatory from Fort Sumner, New Mexico, to study the universe’s baby picture. Meet PIPER! The Primordial Inflation Polarization Explorer will fly at the edge of our atmosphere to look for subtle patterns in the CMB.

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The CMB is cold. Really, really cold. The average temperature is around minus 455 degrees Fahrenheit. It formed 380,000 years after the big bang, which scientists think happened about 13.8 billion years ago. When it was first discovered, the CMB temperature looked very uniform, but researchers later found there are slight variations like hot and cold spots. The CMB is the oldest light in the universe that we can see. Anything before the CMB is foggy — literally.

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Credit: Rob van Hal

Before the CMB, the universe was a fog of hot, dense plasma. (By hot, we’re talking about 500 million degrees F.) That’s so hot that atoms couldn’t exist yet – there was just a soup of electrons and protons. Electrons are great at deflecting light. So, any light that existed in the first few hundred thousand years after the big bang couldn’t travel very far before bouncing off electrons, similar to the way a car’s headlights get diffused in fog.  

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After the big bang, the universe started expanding rapidly in all directions. This expansion is still happening today. As the universe continued to expand, it cooled. By the time the universe reached its 380,000th birthday, it had cooled enough that electrons and protons could combine into hydrogen atoms for the first time. (Scientists call this era recombination.) Hydrogen atoms don’t deflect light nearly as well as loose electrons and the fog lifted. Light could now travel long distances across the universe.

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The light we see in the CMB comes from the recombination era. As it traveled across the universe, through the formation of stars and galaxies, it lost energy. Now we observe it in the microwave part of the electromagnetic spectrum, which is less energetic than visible light and therefore invisible to our eyes. The first baby photo of the CMB – really, a map of the sky in microwaves – came from our Cosmic Background Explorer, which operated from 1989 to 1993.

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Why are we so interested in the universe’s baby picture? Well, it’s helped us learn a lot about the structure of the universe around us today. For example, the Wilkinson Microwave Anisotropy Probe produced a detailed map of the CMB and helped us learn that the universe is 68 percent dark energy, 27 percent dark matter and just 5 percent normal matter — the stuff that you and stars are made of.

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Right after the big bang, we’re pretty sure the universe was tiny. Really tiny. Everything we see today would have been stuffed into something smaller than a proton. If the universe started out that small, then it would have followed the rules of quantum mechanics. Quantum mechanics allows all sorts of strange things to happen. Matter and energy can be “borrowed” from the future then crash back into nothingness. And then cosmic inflation happened and the universe suddenly expanded by a trillion trillion times.

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All this chaos creates a sea of gravitational waves. (These are called “primordial” gravitational waves and come from a different source than the gravitational waves you may have heard about from merging neutron stars and black holes.) The signal of the primordial gravitational waves is a bit like white noise, where the signal from merging dead stars is like a whistle you can pick up over the noise.

These gravitational waves filled the baby universe and created distinct patterns, called B-mode polarization, in the CMB light. These patterns have handedness, which means even though they’re mirror images of each other, they’re not symmetrical — like trying to wear a left-hand glove on your right hand. They’re distinct from another kind of polarization called E-mode, which is symmetrical and echoes the distribution of matter in the universe.

That’s where PIPER comes in. PIPER’s two telescopes sit in a hot-tub-sized container of liquid helium, which runs about minus 452 degrees F. It’ll look at 85 percent of the sky and is extremely sensitive, so it will help us learn even more about the early days of the universe. By telling us more about polarization and those primordial gravitational waves, PIPER will help us understand how the early universe grew from that first baby picture.

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PIPER’s first launch window in Fort Sumner, New Mexico, is in late September. When it’s getting ready to launch, you’ll be able to watch the balloon being filled on the Columbia Scientific Balloon Facility website. Follow NASA Blueshift on Twitter or Facebook for updates about PIPER and when the livestream will be available.

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10 Things to Know About Parker Solar Probe

On Aug. 12, 2018, we launched Parker Solar Probe to the Sun, where it will fly closer than any spacecraft before and uncover new secrets about our star. Here’s what you need to know.

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1. Getting to the Sun takes a lot of power

At about 1,400 pounds, Parker Solar Probe is relatively light for a spacecraft, but it launched to space aboard one of the most powerful rockets in the world, the United Launch Alliance Delta IV Heavy. That’s because it takes a lot of energy to go to the Sun — in fact, 55 times more energy than it takes to go to Mars.

Any object launched from Earth starts out traveling at about the same speed and in the same direction as Earth — 67,000 mph sideways. To get close to the Sun, Parker Solar Probe has to shed much of that sideways speed, and a strong launch is good start.

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2. First stop: Venus!

Parker Solar Probe is headed for the Sun, but it’s flying by Venus along the way. This isn’t to see the sights — Parker will perform a gravity assist at Venus to help draw its orbit closer to the Sun. Unlike most gravity assists, Parker will actually slow down, giving some orbital energy to Venus, so that it can swing closer to the Sun.

One’s not enough, though. Parker Solar Probe will perform similar maneuvers six more times throughout its seven-year mission!

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3. Closer to the Sun than ever before

At its closest approach toward the end of its seven-year prime mission, Parker Solar Probe will swoop within 3.83 million miles of the solar surface. That may sound pretty far, but think of it this way: If you put Earth and the Sun on opposite ends of an American football field, Parker Solar Probe would get within four yards of the Sun’s end zone. The current record-holder was a spacecraft called Helios 2, which came within 27 million miles, or about the 30 yard line. Mercury orbits at about 36 million miles from the Sun.

This will place Parker well within the Sun’s corona, a dynamic part of its atmosphere that scientists think holds the keys to understanding much of the Sun’s activity.

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4. Faster than any human-made object

Parker Solar Probe will also break the record for the fastest spacecraft in history. On its final orbits, closest to the Sun, the spacecraft will reach speeds up to 430,000 mph. That’s fast enough to travel from New York to Tokyo in less than a minute!

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5. Dr. Eugene Parker, mission namesake

Parker Solar Probe is named for Dr. Eugene Parker, the first person to predict the existence of the solar wind. In 1958, Parker developed a theory showing how the Sun’s hot corona — by then known to be millions of degrees Fahrenheit — is so hot that it overcomes the Sun’s gravity. According to the theory, the material in the corona expands continuously outwards in all directions, forming a solar wind.

This is the first NASA mission to be named for a living person, and Dr. Parker watched the launch with the mission team from Kennedy Space Center in Florida.

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6. Unlocking the secrets of the solar wind

Even though Dr. Parker predicted the existence of the solar wind 60 years ago, there’s a lot about it we still don’t understand. We know now that the solar wind comes in two distinct streams, fast and slow. We’ve identified the source of the fast solar wind, but the slow solar wind is a bigger mystery.

Right now, our only measurements of the solar wind happen near Earth, after it has had tens of millions of miles to blur together, cool down and intermix. Parker’s measurements of the solar wind, just a few million miles from the Sun’s surface, will reveal new details that should help shed light on the processes that send it speeding out into space.

7. Studying near-light speed particles

Another question we hope to answer with Parker Solar Probe is how some particles can accelerate away from the Sun at mind-boggling speeds — more than half the speed of light, or upwards of 90,000 miles per second. These particles move so fast that they can reach Earth in under half an hour, so they can interfere with electronics on board satellites with very little warning.

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8. The mystery of the corona’s high heat

The third big question we hope to answer with this mission is something scientists call the coronal heating problem. Temperatures in the Sun’s corona, where Parker Solar Probe will fly, spike upwards of 2 million degrees Fahrenheit, while the Sun’s surface below simmers at a balmy 10,000 F. How the corona gets so much hotter than the surface remains one of the greatest unanswered questions in astrophysics.

Though scientists have been working on this problem for decades with measurements taken from afar, we hope measurements from within the corona itself will help us solve the coronal heating problem once and for all.

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9. Why won’t Parker Solar Probe melt?

The corona reaches millions of degrees Fahrenheit, so how can we send a spacecraft there without it melting?

The key lies in the distinction between heat and temperature. Temperature measures how fast particles are moving, while heat is the total amount of energy that they transfer. The corona is incredibly thin, and there are very few particles there to transfer energy — so while the particles are moving fast (high temperature), they don’t actually transfer much energy to the spacecraft (low heat).

It’s like the difference between putting your hand in a hot oven versus putting it in a pot of boiling water (don’t try this at home!). In the air of the oven, your hand doesn’t get nearly as hot as it would in the much denser water of the boiling pot.

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10. Engineered to thrive in an extreme environment

Make no mistake, the environment in the Sun’s atmosphere is extreme — hot, awash in radiation, and very far from home — but Parker Solar Probe is engineered to survive.

The spacecraft is outfitted with a cutting-edge heat shield made of a carbon composite foam sandwiched between two carbon plates. The heat shield is so good at its job that, even though the front side will receive the full brunt of the Sun’s intense light, reaching 2,500 F, the instruments behind it, in its shadow, will remain at a cozy 85 F.

Even though Parker Solar Probe’s solar panels — which provide the spacecraft’s power — are retractable, even the small bit of surface area that peeks out near the Sun is enough to make them prone to overheating. So, to keep its cool, Parker Solar Probe circulates a single gallon of water through the solar arrays. The water absorbs heat as it passes behind the arrays, then radiates that heat out into space as it flows into the spacecraft’s radiator.

For much of its journey, Parker Solar Probe will be too far from home and too close to the Sun for us to command it in real time — but don’t worry, Parker Solar Probe can think on its feet. Along the edges of the heat shield’s shadow are seven sensors. If any of these sensors detect sunlight, they alert the central computer and the spacecraft can correct its position to keep the sensors — and the rest of the instruments — safely protected behind the heat shield.

Read the web version of this week’s “Solar System: 10 Things to Know” article HERE.

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Gravity, Hazard of Alteration

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, NASA’s Human Research Program has organized some of the hazards
astronauts will encounter on a continual basis into five classifications.

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The variance of gravity fields that
astronauts will encounter on a mission to Mars is the fourth hazard.

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On Mars, astronauts would need to
live and work in three-eighths of Earth’s gravitational pull for up to two
years. Additionally, on the six-month trek between the planets, explorers will
experience total weightlessness. 

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Besides Mars and deep space there
is a third gravity field that must be considered. When astronauts finally
return home they will need to readapt many of the systems in their bodies to
Earth’s gravity.

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To further complicate the problem,
when astronauts transition from one gravity field to another, it’s usually
quite an intense experience. Blasting off from the surface of a planet or a
hurdling descent through an atmosphere is many times the force of gravity.

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Research is being conducted to
ensure that astronauts stay healthy before, during and after their mission.
Specifically researchers study astronauts’
vision, fine motor skills, fluid distribution, exercise protocols and response to
pharmaceuticals.

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Exploration to the Moon and Mars will expose astronauts to five
known hazards of spaceflight, including gravity. To learn more, and find out
what NASA’s 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 gravity with Peter
Norsk,
Senior Research Director/ Element Scientist at
the Johnson Space Center.

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Black Holes are NICER Than You Think!

We’re learning more every day about black holes thanks to one of the instruments aboard the International Space Station! Our Neutron star Interior Composition Explorer (NICER) instrument is keeping an eye on some of the most mysterious cosmic phenomena.

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We’re going to talk about some of the amazing new things NICER is showing us about black holes. But first, let’s talk about black holes — how do they work, and where do they come from? There are two important types of black holes we’ll talk about here: stellar and supermassive. Stellar mass black holes are three to dozens of times as massive as our Sun while supermassive black holes can be billions of times as massive!

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Stellar black holes begin with a bang — literally! They are one of the possible objects left over after a large star dies in a supernova explosion. Scientists think there are as many as a billion stellar mass black holes in our Milky Way galaxy alone!

Supermassive black holes have remained rather mysterious in comparison. Data suggest that supermassive black holes could be created when multiple black holes merge and make a bigger one. Or that these black holes formed during the early stages of galaxy formation, born when massive clouds of gas collapsed billions of years ago. There is very strong evidence that a supermassive black hole lies at the center of all large galaxies, as in our Milky Way.

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Imagine an object 10 times more massive than the Sun squeezed into a sphere approximately the diameter of New York City — or cramming a billion trillion people into a car! These two examples give a sense of how incredibly compact and dense black holes can be.

Because so much stuff is squished into such a relatively small volume, a black hole’s gravity is strong enough that nothing — not even light — can escape from it. But if light can’t escape a dark fate when it encounters a black hole, how can we “see” black holes?

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Scientists can’t observe black holes directly, because light can’t escape to bring us information about what’s going on inside them. Instead, they detect the presence of black holes indirectly — by looking for their effects on the cosmic objects around them. We see stars orbiting something massive but invisible to our telescopes, or even disappearing entirely!

When a star approaches a black hole’s event horizon — the point of no return — it’s torn apart. A technical term for this is “spaghettification” — we’re not kidding! Cosmic objects that go through the process of spaghettification become vertically stretched and horizontally compressed into thin, long shapes like noodles.

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Scientists can also look for accretion disks when searching for black holes. These disks are relatively flat sheets of gas and dust that surround a cosmic object such as a star or black hole. The material in the disk swirls around and around, until it falls into the black hole. And because of the friction created by the constant movement, the material becomes super hot and emits light, including X-rays.  

At last — light! Different wavelengths of light coming from accretion disks are something we can see with our instruments. This reveals important information about black holes, even though we can’t see them directly.

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So what has NICER helped us learn about black holes? One of the objects this instrument has studied during its time aboard the International Space Station is the ever-so-forgettably-named black hole GRS 1915+105, which lies nearly 36,000 light-years — or 200 million billion miles — away, in the direction of the constellation Aquila.

Scientists have found disk winds — fast streams of gas created by heat or pressure — near this black hole. Disk winds are pretty peculiar, and we still have a lot of questions about them. Where do they come from? And do they change the shape of the accretion disk?

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It’s been difficult to answer these questions, but NICER is more sensitive than previous missions designed to return similar science data. Plus NICER often looks at GRS 1915+105 so it can see changes over time.

NICER’s observations of GRS 1915+105 have provided astronomers a prime example of disk wind patterns, allowing scientists to construct models that can help us better understand how accretion disks and their outflows around black holes work.

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NICER has also collected data on a stellar mass black hole with another long name — MAXI J1535-571 (we can call it J1535 for short) — adding to information provided by NuSTAR, Chandra, and MAXI. Even though these are all X-ray detectors, their observations tell us something slightly different about J1535, complementing each other’s data!

This rapidly spinning black hole is part of a binary system, slurping material off its partner, a star. A thin halo of hot gas above the disk illuminates the accretion disk and causes it to glow in X-ray light, which reveals still more information about the shape, temperature, and even the chemical content of the disk. And it turns out that J1535’s disk may be warped!

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Image courtesy of NRAO/AUI and Artist: John Kagaya (Hoshi No Techou)

This isn’t the first time we have seen evidence for a warped disk, but J1535’s disk can help us learn more about stellar black holes in binary systems, such as how they feed off their companions and how the accretion disks around black holes are structured.

NICER primarily studies neutron stars — it’s in the name! These are lighter-weight relatives of black holes that can be formed when stars explode. But NICER is also changing what we know about many types of X-ray sources. Thanks to NICER’s efforts, we are one step closer to a complete picture of black holes. And hey, that’s pretty nice!

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