Space Telescope Gets To Work

We’re honored to be recognized as one of 2015’s new and notable Tumblrs! Thanks for following along as we explore the universe and discover our home planet.

New and Notable Tumblrs of 2015 - Part 1

We’d like to recognize these distinguished Tumblrs for achievement in Being So Good.

NASA

GISHWHES

Sheldon the Tiny Dinosaur

Afro Arts

Karlie Kloss

Actual Dog Vines

Nike Women

Magic: The Gathering

Post It Forward

Book Quotes

Good Things by Ellen

Just Bad Puns

How to Get Away with Paint

Google Sheep View

What’s Up for October?

This month is filled with exciting celestial sights. Here are 10 targets you can view this month:

10. Unusual Sunset

During a sunset, our thick atmosphere absorbs most colors of sunlight, but red light is absorbed the least. Rarely, green flashes can be seen just above the sun’s edge. As the last sliver of the disk disappears below the horizon, be sure to watch its color.

9. Belt of Venus

Just after sunset, turn around and face east. A dark shadow will move up from the horizon and gradually cover the pinkish sky. This is caused from the Earth itself blocking the sunlight and is called the Earth Shadow or the Belt of Venus.

8. Crepuscular Rays

Also just after sunset, or before dawn, you may see rays of sunlight spread like a fan. These are called crepuscular rays and are formed when sunlight streams through gaps in the clouds or mountains.

7. Aurora Borealis

The northern lights, also known as the aurora borealis, are caused by collisions between gaseous particles in Earth’s atmosphere and charged particles released from the sun. The color of the lights can changed depending on the type of gas being struck by particles of solar wind. You can find out when and where to expect aurorae at the Space Weather Prediction Center.

6. Andromeda Galaxy

Did you now that The Andromeda Galaxy is one of the few you can actually see with your naked eye? In October, look nearly overhead after sunset to see it! This galaxy is more than twice the apparent width of the moon.

5. Moon Features

Nights in mid-October are excellent for viewing the features on the moon. Areas like the Sea of Tranquility and the site of the 1969 Apollo 11 landing will be visible.

4. A Comet

This month, the European Space Agency’s Rosetta mission target, a comet with a complicated name (Comet 67P Churyumov-Gerasimenko), is still bright enough for experienced astronomers to pick out in a dark sky. On October 9, you may be able to spot it in the east near the crescent moon and Venus.

3. Meteor Showers

There are multiple meteor showers this month. On the 9th: watch the faint, slow-moving Draconids. On the 10th: catch the slow, super-bright Taurids. And on the 21st: don’t’ miss the swift and bright Orionids from the dust of Comet Halley.

2. Three Close Planets

On October 28, you’ll find a tight grouping of Jupiter, Venus and Mars in the eastern sky before sunrise.

1. Zodiacal Light

The Zodiacal light is a faint triangular glow that can be seen from a dark sky after sunset or before sunrise. What you’re seeing is sunlight reflecting off dust grains that circle the sun in the inner solar system. These dust grains travel in the same plane as the moon and planets as they journey across our sky.

For more stargazing tools visit: Star Tool Box

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

What's Inside SOFIA? High Flying Instruments

Our flying observatory, called SOFIA, carries a 100-inch telescope inside a Boeing 747SP aircraft. Having an airborne observatory provides many benefits.

It flies at 38,000-45,000 feet – above 99% of the water vapor in Earth’s atmosphere that blocks infrared light from reaching the ground! 

It is also mobile! We can fly to the best vantage point for viewing the cosmos. We go to Christchurch, New Zealand, nearly every year to study objects best observed from the Southern Hemisphere. And last year we went to Daytona Beach, FL, to study the atmosphere of Neptune’s moon Triton while flying over the Atlantic Ocean.

SOFIA’s telescope has a large primary mirror – about the same size as the Hubble Space Telescope’s mirror. Large telescopes let us gather a lot of light to make high-resolution images!

But unlike a space-based observatory, SOFIA returns to our base every morning.

Which means that we can change the instruments we use to analyze the light from the telescope to make many different types of scientific observations. We currently have seven instruments, and new ones are now being developed to incorporate new technologies.

So what is inside SOFIA? The existing instruments include:

Infrared cameras that can peer inside celestial clouds of dust and gas to see stars forming inside. They can also study molecules in a nebula that may offer clues to the building blocks of life…

…A polarimeter, a device that measures the alignment of incoming light waves, that we use to study magnetic fields. The left image reveals that hot dust in the starburst galaxy M82 is magnetically aligned with the gas flowing out of it, shown in blue on the right image from our Chandra X-ray Observatory. This can help us understand how magnetic fields affect how stars form.

…A tracking camera that we used to study New Horizon’s post-Pluto flyby target and found that it may have its own moon…

…A spectrograph that spreads light into its component colors. We’re using one to search for signs of water plumes on Jupiter’s icy moon Europa and to search for signs of water on Venus to learn about how it lost its oceans…

…An instrument that studies high energy terahertz radiation with 14 detectors. It’s so efficient that we made this map of Orion’s Horsehead Nebula in only four hours! The map is made of 100 separate views of the nebula, each mapping carbon atoms at different velocities.

…And we have an instrument under construction that will soon let us study how water vapor, ice and oxygen combine at different times during planet formation, to better understand how these elements combine with dust to form a mass that can become a planet.

Our airborne telescope has already revealed so much about the universe around us! Now we’re looking for the next idea to help us use SOFIA in even more new ways. 

Discover more about our SOFIA flying observatory HERE. 

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

What was your favourite NASA mission or project?

Follow our Mars 2020 rover, named Perseverance or “Percy,” on Twitter to keep up with all its progress and discoveries!

Percy: https://twitter.com/NASAPersevere

New Science from our Mission to Touch the Sun

In August 2018, our Parker Solar Probe mission launched to space, soon becoming the closest-ever spacecraft from the Sun. Now, scientists have announced their first discoveries from this exploration of our star!

The Sun may look calm to us here on Earth, but it's an active star, unleashing powerful bursts of light, deluges of particles moving near the speed of light and billion-ton clouds of magnetized material. All of this activity can affect our technology here on Earth and in space.

Parker Solar Probe's main science goals are to understand the physics that drive this activity — and its up-close look has given us a brand-new perspective. Here are a few highlights from what we've learned so far.

1. Surprising events in the solar wind

The Sun releases a continual outflow of magnetized material called the solar wind, which shapes space weather near Earth. Observed near Earth, the solar wind is a relatively uniform flow of plasma, with occasional turbulent tumbles. Closer to the solar wind's source, Parker Solar Probe saw a much different picture: a complicated, active system. 

One type of event in particular drew the eye of the science teams: flips in the direction of the magnetic field, which flows out from the Sun, embedded in the solar wind. These reversals — dubbed "switchbacks" — last anywhere from a few seconds to several minutes as they flow over Parker Solar Probe. During a switchback, the magnetic field whips back on itself until it is pointed almost directly back at the Sun.

The exact source of the switchbacks isn't yet understood, but Parker Solar Probe's measurements have allowed scientists to narrow down the possibilities — and observations from the mission's 21 remaining solar flybys should help scientists better understand these events. 

2. Seeing tiny particle events

The Sun can accelerate tiny electrons and ions into storms of energetic particles that rocket through the solar system at nearly the speed of light. These particles carry a lot of energy, so they can damage spacecraft electronics and even endanger astronauts, especially those in deep space, outside the protection of Earth's magnetic field — and the short warning time for such particles makes them difficult to avoid.

Energetic particles from the Sun impact a detector on ESA & NASA's SOHO satellite.

Parker Solar Probe's energetic particle instruments have measured several never-before-seen events so small that all trace of them is lost before they reach Earth. These instruments have also measured a rare type of particle burst with a particularly high number of heavier elements — suggesting that both types of events may be more common than scientists previously thought.

3. Rotation of the solar wind

Near Earth, we see the solar wind flowing almost straight out from the Sun in all directions. But the Sun rotates as it releases the solar wind, and before it breaks free, the wind spins along in sync with the Sun's surface. For the first time, Parker was able to observe the solar wind while it was still rotating – starting more than 20 million miles from the Sun.

The strength of the circulation was stronger than many scientists had predicted, but it also transitioned more quickly than predicted to an outward flow, which helps mask the effects of that fast rotation from the vantage point where we usually see them from, near Earth, about 93 million miles away. Understanding this transition point in the solar wind is key to helping us understand how the Sun sheds energy, with implications for the lifecycles of stars and the formation of protoplanetary disks.

4. Hints of a dust-free zone

Parker also saw the first direct evidence of dust starting to thin out near the Sun – an effect that has been theorized for nearly a century, but has been impossible to measure until now. Space is awash in dust, the cosmic crumbs of collisions that formed planets, asteroids, comets and other celestial bodies billions of years ago. Scientists have long suspected that, close to the Sun, this dust would be heated to high temperatures by powerful sunlight, turning it into a gas and creating a dust-free region around the Sun.

For the first time, Parker's imagers saw the cosmic dust begin to thin out a little over 7 million miles from the Sun. This decrease in dust continues steadily to the current limits of Parker Solar Probe's instruments, measurements at a little over 4 million miles from the Sun. At that rate of thinning, scientists expect to see a truly dust-free zone starting a little more than 2-3 million miles from the Sun — meaning the spacecraft could observe the dust-free zone as early as 2020, when its sixth flyby of the Sun will carry it closer to our star than ever before.

These are just a few of Parker Solar Probe's first discoveries, and there's plenty more science to come throughout the mission! For the latest on our Sun, follow @NASASun on Twitter and NASA Sun Science on Facebook.

Farewell to the Van Allen Probes

After seven years of studying the radiation around Earth, the Van Allen Probes spacecraft have retired.

Originally slated for a two-year mission, these two spacecraft studied Earth's radiation belts — giant, donut-shaped clouds of particles surrounding Earth — for nearly seven years. The mission team used the last of their propellant this year to place the spacecraft into a lower orbit that will eventually decay, allowing the Van Allen Probes to re-enter and burn up in Earth's atmosphere.

Earth's radiation belts exist because energized charged particles from the Sun and other sources in space become trapped in our planet's huge magnetic field, creating vast regions around Earth that teem with radiation. This is one of the harshest environments in space — and the Van Allen Probes survived more than three times longer than planned orbiting through this intense region.

The shape, size and intensity of the radiation belts change, meaning that satellites — like those used for telecommunications and GPS — can be bombarded with a sudden influx of radiation. The Van Allen Probes shed new light on what invisible forces drive these changes — like waves of charged particles and electromagnetic fields driven by the Sun, called space weather. 

Here are a few scientific highlights from the Van Allen Probes — from the early days of the mission to earlier this year:

The Van Allen belts were first discovered in 1958, and for decades, scientists thought there were only two concentric belts. But, days after the Van Allen Probes launched, scientists discovered that during times of intense solar activity, a third belt can form.

The belts are composed of charged particles and electromagnetic fields and can be energized by different types of plasma waves. One type, called electrostatic double layers, appear as short blips of enhanced electric field. During one observing period, Probe B saw 7,000 such blips repeatedly pass over the spacecraft in a single minute!

During big space weather storms, which are ultimately caused by activity on the Sun, ions — electrically charged atoms or molecules — can be pushed deep into Earth’s magnetosphere. These particles carry electromagnetic currents that circle around the planet and can dramatically distort Earth’s magnetic field.

Across space, fluctuating electric and magnetic fields can create what are known as plasma waves. These waves intensify during space weather storms and can accelerate particles to incredible speeds. The Van Allen Probes found that one type of plasma wave known as hiss can contribute greatly to the loss of electrons from the belts.

The Van Allen belts are composed of electrons and ions with a range of energies. In 2015, research from the Van Allen Probes found that, unlike the outer belt, there were no electrons with energies greater than a million electron volts in the inner belt.

Plasma waves known as whistler chorus waves are also common in our near-Earth environment. These waves can travel parallel or at an angle to the local magnetic field. The Van Allen Probes demonstrated the two types of waves cannot be present simultaneously, resulting in greater radiation belt particle scattering in certain areas.

Very low frequency chorus waves, another variety of plasma waves, can pump up the energy of electrons to millions of electronvolts. During storm conditions, the Van Allen Probes found these waves can hugely increase the energy of particles in the belts in just a few hours.  

Scientists often use computer simulation models to understand the physics behind certain phenomena. A model simulating particles in the Van Allen belts helped scientists understand how particles can be lost, replenished and trapped by Earth’s magnetic field.

The Van Allen Probes observed several cases of extremely energetic ions speeding toward Earth. Research found that these ions’ acceleration was connected to their electric charge and not to their mass.

The Sun emits faster and slower gusts of charged particles called the solar wind. Since the Sun rotates, these gusts — the fast wind — reach Earth periodically. Changes in these gusts cause the extent of the region of cold ionized gas around Earth — the plasmasphere — to shrink. Data from the Van Allen Probes showed that such changes in the plasmasphere fluctuated at the same rate as the solar rotation — every 27 days.

Though the mission has ended, scientists will use data from the Van Allen Probes for years to come. See the latest Van Allen Probes science at nasa.gov/vanallen.

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

What is some advice that really helped you get to where you are now?

How did you choose your Flight Director name?

Which Landsat Image Do You Love?

Feeling competitive? We’ve got a game for you to play in! Tournament Earth: The Landsat Games is happening right now, and as we get to the final entries, the competition is heating up.

You can help us pick the winner by voting for one of the remaining four Landsat images of our home planet! Our competition started with 32 images, divided into categories by what they show: land, water, ice & snow, and human impact.

So, what do you think? Which one of these images is going for gold?

Land

First up, we have an image of the Markha River and surrounding Central Siberian Plateau, acquired in 2020 by Landsat 8. The hypnotic undulations of striping across the landscape carried this image to victory over the rest of the Land images -- a particularly tough category, given that these images all come from Landsat.

Water

It’s not all land, though! The bright blues and greens of this false-color image of the Atchafalaya Delta in Louisiana helped carry it to victory in the Water category. The image, taken in 2020 by Landsat 8, shows a region that’s subject to erosion of land by wind and rising sea levels.

Ice & Snow

Brrr! Did it get cold in here? That’s the finalist from the Ice and Snow category, an image of sea ice around Russia’s New Siberian Islands. The image, collected by Landsat 8 in June 2016, shows sea ice during its annual seasonal breakup.

Human Impact

Humans have been shaping the planet around us for hundreds of years. Some changes, like rice fields in the Sacramento Valley, are visible from space. Landsat 8 collected this false-color image of flooded rice fields in December 2018.

So, now it’s up to you! Which image is your favorite? There can only be one winner of Tournament Earth: The Landsat Games. Get your vote in, and then get ready to watch as we launch the next Landsat satellite, Landsat 9, in September.

The Landsat mission is a partnership between us at NASA and the U.S. Geological Survey. Together, we’ve been using Landsat satellites to collect nearly 50 years of images of our home planet.

Make sure to follow us on Tumblr for your regular dose of space.

For Earth Day, we’re inviting you to take a moment to celebrate our wonderful water world, Earth. As far as we know, our Blue Marble is the only place in the universe with life, and that life depends on water. Snap a photo of yourself outside and tag it #GlobalSelfie – bonus points if your selfie features your favorite body of water! http://go.nasa.gov/3xFt0H0

Make sure to follow us on Tumblr for your regular dose of space!