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From Seed to Market: How NASA brings food to the table

Did you know we help farmers grow some of your favorite fruits, veggies and grains?

Our Earth-observing satellites track rainfall amounts, soil moisture, crop health, and more. On the ground, we partner with agencies and organizations around the world to help farmers use that data to care for their fields.

Here are a few ways we help put food on the table, from planting to harvest.

Planting

Did you plant seeds in science class to watch them sprout and grow? They all needed water, right? Our data helps farmers “see” how moist the soil is across large fields.

“When you’re not sure when to water your flowers or your garden, you can look at the soil or touch it with your hands. We are sort of ‘feeling’ the soil, sensing how much water is in the soil – from a satellite,

685 kilometers (408 miles) above Earth,” said John Bolten, the associate program manager of water resources for NASA’s Applied Sciences Program.

This spring, we worked with the U.S. Department of Agriculture and George Mason University to release Crop-CASMA, a tool that shows soil moisture and vegetation conditions for the United States. Able to see smaller areas – about the size of a couple of golf courses – the USDA uses Crop-CASMA to help update farmers on their state’s soil moisture, crop health and growing progress.

Growing

It’s dangerous being a seedling.

Heavy spring rains or summer storms can flood fields and drown growing plants. Dry spells and droughts can starve them of nutrients. Insects and hail can damage them. Farmers need to keep a close eye on plants during the spring and summer months. Our data and programs help them do that.

For example, in California, irrigation is essential for agriculture. California’s Central Valley annually produces more than 250 types of crops and is one of the most productive agricultural regions in the country – but it’s dry. Some parts only get 6 inches of rain per year.

To help, Landsat data powers CropManage – an app that tells farmers how long to irrigate their fields, based on soil conditions and evapotranspiration, or how much water plants are releasing into the atmosphere. The warmer and drier the atmosphere, the more plants “sweat” and lose water that needs to be replenished. Knowing how long to irrigate helps farmers conserve water and be more efficient. In years like 2021, intense droughts can make water management especially critical.

Harvest

Leading up to harvest, farmers need to know their expected yields – and profits.

GEOGLAM, or the Group on Earth Observations Global Agricultural Monitoring Initiative, is a partnership between NASA Harvest, USDA’s Foreign Agricultural Service (FAS) and other global agencies to track and report on crop conditions around the world.

USDA FAS is one of the main users of a soil moisture measurement product developed by Bolten and his team at our NASA Goddard Space Flight Center to drive their crop forecasting system.

If you’re interested in more ways we support agriculture, stay tuned over the next few weeks to learn more about how satellites (and scientists) help put snacks on your table!

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Bill Nye for most of his career: Imma do science for kids. Science without politics. Nice, tame science for the kiddos.

Bill Nye now:

The Stellar Buddy System

Our Sun has an entourage of planets, moons, and smaller objects to keep it company as it traverses the galaxy. But it’s still lonely compared to many of the other stars out there, which often come in pairs. These cosmic couples, called binary stars, are very important in astronomy because they can easily reveal things that are much harder to learn from stars that are on their own. And some of them could even host habitable planets!

The birth of a stellar duo

New stars emerge from swirling clouds of gas and dust that are peppered throughout the galaxy. Scientists still aren’t sure about all the details, but turbulence deep within these clouds may give rise to knots that are denser than their surroundings. The knots have stronger gravity, so they can pull in more material and the cloud may begin to collapse.

The material at the center heats up. Known as a protostar, it is this hot core that will one day become a star. Sometimes these spinning clouds of collapsing gas and dust may break up into two, three, or even more blobs that eventually become stars. That would explain why the majority of the stars in the Milky Way are born with at least one sibling.

Seeing stars

We can’t always tell if we’re looking at binary stars using just our eyes. They’re often so close together in the sky that we see them as a single star. For example, Sirius, the brightest star we can see at night, is actually a binary system (see if you can spot both stars in the photo above). But no one knew that until the 1800s.

Precise observations showed that Sirius was swaying back and forth like it was at a middle school dance. In 1862, astronomer Alvan Graham Clark used a telescope to see that Sirius is actually two stars that orbit each other.

But even through our most powerful telescopes, some binary systems still masquerade as a single star. Fortunately there are a couple of tricks we can use to spot these pairs too.

Since binary stars orbit each other, there’s a chance that we’ll see some stars moving toward and away from us as they go around each other. We just need to have an edge-on view of their orbits. Astronomers can detect this movement because it changes the color of the star’s light – a phenomenon known as the Doppler effect.

Stars we can find this way are called spectroscopic binaries because we have to look at their spectra, which are basically charts or graphs that show the intensity of light being emitted over a range of energies. We can spot these star pairs because light travels in waves. When a star moves toward us, the waves of its light arrive closer together, which makes its light bluer. When a star moves away, the waves are lengthened, reddening its light.

Sometimes we can see binary stars when one of the stars moves in front of the other. Astronomers find these systems, called eclipsing binaries, by measuring the amount of light coming from stars over time. We receive less light than usual when the stars pass in front of each other, because the one in front will block some of the farther star’s light.

Sibling rivalry

Twin stars don’t always get along with each other – their relationship may be explosive! Type Ia supernovae happen in some binary systems in which a white dwarf – the small, hot core left over when a Sun-like star runs out of fuel and ejects its outer layers – is stealing material away from its companion star. This results in a runaway reaction that ultimately detonates the thieving star. The same type of explosion may also happen when two white dwarfs spiral toward each other and collide. Yikes!

Scientists know how to determine how bright these explosions should truly be at their peak, making Type Ia supernovae so-called standard candles. That means astronomers can determine how far away they are by seeing how bright they look from Earth. The farther they are, the dimmer they appear. Astronomers can also look at the wavelengths of light coming from the supernovae to find out how fast the dying stars are moving away from us.

Studying these supernovae led to the discovery that the expansion of the universe is speeding up. Our Nancy Grace Roman Space Telescope will scan the skies for these exploding stars when it launches in the mid-2020s to help us figure out what’s causing the expansion to accelerate – a mystery known as dark energy.

Spilling stellar secrets

Astronomers like finding binary systems because it’s a lot easier to learn more about stars that are in pairs than ones that are on their own. That’s because the stars affect each other in ways we can measure. For example, by paying attention to how the stars orbit each other, we can determine how massive they are. Since heavier stars burn hotter and use up their fuel more quickly than lighter ones, knowing a star’s mass reveals other interesting things too.

By studying how the light changes in eclipsing binaries when the stars cross in front of each other, we can learn even more! We can figure out their sizes, masses, how fast they’re each spinning, how hot they are, and even how far away they are. All of that helps us understand more about the universe.

Tatooine worlds

Thanks to observatories such as our Kepler Space Telescope, we know that worlds like Luke Skywalker’s home planet Tatooine in “Star Wars” exist in real life. And if a planet orbits at the right distance from the two stars, it could even be habitable (and stay that way for a long time).

In 2019, our Transiting Exoplanet Survey Satellite (TESS) found a planet, known as TOI-1338 b, orbiting a pair of stars. These worlds are tricker to find than planets with only one host star, but TESS is expected to find several more!

Want to learn more about the relationships between stellar couples? Check out this Tumblr post: https://nasa.tumblr.com/post/190824389279/cosmic-couples-and-devastating-breakups

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

“Electrostatic force is that which governs the motion of the atoms. It is the force which causes them to collide and develop the life-sustaining energy of heat and light, and which causes them to aggregate in an infinite variety of ways, according to Nature’s fanciful designs, and forms all these wondrous structures we see around us. It is, in fact, if our present views be true, the most important force for us to consider in Nature.”

–Nikola Tesla 

“Tesla, Marvel Of The Future.” Brooklyn Citizen, August 22, 1897.

Is there any chance that something could go wrong?

I hope you will enjoy this Halloween special. Today, we are trying something a little bit different by exploring the evolution of a particular animal : Bats.

While their evolutionary history is shrouded in mystery, they allow us, nonetheless, to explore 2 interesting ideas :

1- Convergent evolution : How organisms tend to evolve similar (albeit not identical) body plans as solutions to similar problems (flight in birds, bats and pterosaurs)

2- Prediction : Like any theory, evolution is not only descriptive, but also predictive. Thanks to its models and principles, it allows us to make predictions to complement our gap in observational data.

Happy Halloween!

P.S. : The blog in the third picture is neither scientific nor peer-reviewed. But it is a nice illustration of how the common ancestor of bats MIGHT have looked like, and how using basic principles from evolution, phylogeny, and comparative anatomy, we can visualize how some animals have come to be what they are.

A small question:

Would anybody want me to do lessons? Like if you send in an ask like 'Hey, what do you know abt *science topic*?' I could do some research and make it a post with links and videos? (Like my Gravitational Waves in the Space-Time Continuum post [link below, and pinned to my acct])

Space Boii

Einstein's Theories of Relativity

Gravitational Waves in the Space-Time Continuum Einstein has two theories of relativity. The first is The Theory of Special Relativity (1905

Would anybody send in asks???

SHIELDS Up! NASA Rocket to Survey Our Solar System’s Windshield Apr 16, 2021

Eleven billion miles away – more than four times the distance from us to Pluto – lies the boundary of our solar system’s magnetic bubble, the heliopause. Here the Sun’s magnetic field, stretching through space like an invisible cobweb, fizzles to nothing. Interstellar space begins. “It’s really the largest boundary of its kind we can study,” said Walt Harris, space physicist at the University of Arizona in Tucson.

We still know little about what lies beyond this boundary. Fortunately, bits of interstellar space can come to us, passing right through this border and making their way into the solar system.

A new NASA mission will study light from interstellar particles that have drifted into our solar system to learn about the closest reaches of interstellar space. The mission, called the Spatial Heterodyne Interferometric Emission Line Dynamics Spectrometer, or SHIELDS, will have its first opportunity to launch aboard a suborbital rocket from the White Sands Missile Range in New Mexico on April 19, 2021.

Our entire solar system is adrift in a cluster of clouds, an area cleared by ancient supernova blasts. Astronomers call this region the Local Bubble, an oblong plot of space about 300 light-years long within the spiraling Orion arm of our Milky Way galaxy. It contains hundreds of stars, including our own Sun.

We fare this interstellar sea is our trusty vessel, the heliosphere, a much smaller (though still gigantic) magnetic bubble blown up by the Sun. As we orbit the Sun, the solar system itself, encased in the heliosphere, hurtles through the Local Bubble at about 52,000 miles per hour (23 kilometers per second). Interstellar particles pelt the nose of our heliosphere like rain against a windshield.

Our heliosphere is more like a rubber raft than a wooden sailboat: Its surroundings mold its shape. It compresses at points of pressure, expands where it gives way. Exactly how and where our heliosphere’s lining deforms gives us clues about the nature of the interstellar space outside it. This boundary – and any deformities in it – are what Walt Harris, principal investigator for the SHIELDS mission, is after.

SHIELDS is a telescope that will launch aboard a sounding rocket, a small vehicle that flies to space for a few minutes of observing time before falling back to Earth. Harris’ team launched an earlier iteration of the telescope as part of the HYPE mission in 2014, and after modifying the design, they’re ready to launch again.

SHIELDS will measure light from a special population of hydrogen atoms originally from interstellar space. These atoms are neutral, with a balanced number of protons and electrons. Neutral atoms can cross magnetic field lines, so they seep through the heliopause and into our solar system nearly unfazed – but not completely.

The small effects of this boundary crossing are key to SHIELDS’s technique. Charged particles flow around the heliopause, forming a barrier. Neutral particles from interstellar space must pass through this gauntlet, which alters their paths. SHIELDS was designed to reconstruct the trajectories of the neutral particles to determine where they came from and what they saw along the way.

A few minutes after launch, SHIELDS will reach its peak altitude of about 186 miles (300 kilometers) from the ground, far above the absorbing effect of Earth’s atmosphere. Pointing its telescope towards the nose of the heliosphere, it will detect light from arriving hydrogen atoms. Measuring how that light’s wavelength stretches or contracts reveals the particles’ speed. All told, SHIELDS will produce a map to reconstruct the shape and varying density of matter at the heliopause.

The data, Harris hopes, will help answer tantalizing questions about what interstellar space is like.

For instance, astronomers think the Local Bubble as a whole is about 1/10th as dense as most of the rest of the galaxy’s main disk. But we don’t know the details – for instance, is matter in the Local Bubble is distributed evenly, or bunched up in dense pockets surrounded by nothingness? “There’s a lot of uncertainty about the fine structure of the interstellar medium – our maps are kind of crude,” Harris said. “We know the general outlines of these clouds, but we don’t know what’s happening inside them.”

Astronomers also don’t know much about the galaxy’s magnetic field. But it should leave a mark on our heliosphere that SHIELDS can detect, compressing the heliopause in a specific way based on its strength and orientation.

Finally, learning what our current plot of interstellar space is like could be a helpful guide for the (distant) future. Our solar system is just passing through our current patch of space. In some 50,000 years, we’ll be on our way out of the Local Bubble and on to who knows what.

“We don’t really know what that other cloud is like, and we don’t know what happens when you cross a boundary into that cloud,” Harris said. “There’s a lot of interest in understanding what we’re likely to experience as our solar system makes that transition.”

Not that our solar system hasn’t done it before. Over the last four billion years, Harris explains, Earth has passed through a variety of interstellar environments. It’s just that now we’re around, with the scientific tools to document it.

“We’re just trying to understand our place in the galaxy, and where we’re headed in the future,” Harris said.

TOP IMAGE….An illustration of the heliosphere being pelted with cosmic rays from outside our solar system. Credit: NASA’s Goddard Space Flight Center/Conceptual Image Lab

LOWER IMAGE….Illustration of the Local Bubble. Credits: NASA’s Goddard Space Flight Center