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Our Sun is More than Meets the Eye

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Our Sun is More than Meets the Eye

The Sun may look unchanging to us here on Earth, but that’s not the whole story.

In visible light – the light our eyes can see – the Sun looks like an almost featureless orange disk, peppered with the occasional sunspot. (Important note: Never look at the Sun directly, and always use a proper filter for solar viewing – or tune in to our near-real time satellite feeds!)

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But in other kinds of light, it’s a different picture. The Sun emits light across the electromagnetic spectrum, including the relatively narrow range of light we can see, as well as wavelengths that are invisible to our eyes. Different wavelengths convey information about different components of the Sun’s surface and atmosphere, so watching the Sun in multiple types of light helps us paint a fuller picture.

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Watching the Sun in these wavelengths reveals how active it truly is. This image, captured in a wavelength of extreme ultraviolet light at 131 Angstroms, shows a solar flare. Solar flares are intense bursts of light radiation caused by magnetic events on the Sun, and often associated with sunspots. The light radiation from solar flares can disturb part of Earth’s atmosphere where radio signals travel, causing short-lived problems with communications systems and GPS.

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Looking at the Sun in extreme ultraviolet light also reveals structures like coronal loops (magnetic loops traced out by charged particles spinning along magnetic field lines)…

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…solar prominence eruptions…

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…and coronal holes (magnetically open areas on the Sun from which solar wind rushes out into space).

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Though extreme ultraviolet light shows the Sun’s true colors, specialized instruments let us see some of the Sun’s most significant activity in visible light.

A coronagraph is a camera that uses a solid disk to block out the Sun’s bright face, revealing the much fainter corona, a dynamic part of the Sun’s atmosphere. Coronagraphs also reveal coronal mass ejections, or CMEs, which are explosions of billions of tons of solar material into space. Because this material is magnetized, it can interact with Earth’s magnetic field and trigger space weather effects like the aurora, satellite problems, and even – in extreme cases – power outages.

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The Sun is also prone to bursts of energetic particles. These particles are blocked by Earth’s magnetic field and atmosphere, but they could pose a threat to astronauts traveling in deep space, and they can interfere with our satellites. This clip shows an eruption of energetic particles impacting a Sun-observing satellite, creating the ‘snow’ in the image.

We keep watch on the Sun 24/7 with a fleet of satellites to monitor and better understand this activity. And this summer, we’re going one step closer with the launch of Parker Solar Probe, a mission to touch the Sun. Parker Solar Probe will get far closer to the Sun than any other spacecraft has ever gone – into the corona, within 4 million miles of the surface – and will send back unprecedented direct measurements from the regions thought to drive much of the Sun’s activity. More information about the fundamental processes there can help round out and improve models to predict the space weather that the Sun sends our way.

Keep up with the latest on the Sun at @NASASun on Twitter, and follow along with Parker Solar Probe’s last steps to launch at nasa.gov/solarprobe.

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

Source: NASA


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Solar System 10 Things: Looking Back at Pluto

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Solar System 10 Things: Looking Back at Pluto

In July 2015, we saw Pluto up close for the first time and—after three years of intense study—the surprises keep coming. “It’s clear,” says Jeffery Moore, New Horizons’ geology team lead, “Pluto is one of the most amazing and complex objects in our solar system.”

1. An Improving View

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These are combined observations of Pluto over the course of several decades. The first frame is a digital zoom-in on Pluto as it appeared upon its discovery by Clyde Tombaugh in 1930. More frames show of Pluto as seen by the Hubble Space Telescope. The final sequence zooms in to a close-up frame of Pluto taken by our New Horizons spacecraft on July 14, 2015.

2. The Heart

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Pluto’s surface sports a remarkable range of subtle colors are enhanced in this view to a rainbow of pale blues, yellows, oranges, and deep reds. Many landforms have their own distinct colors, telling a complex geological and climatological story that scientists have only just begun to decode. The image resolves details and colors on scales as small as 0.8 miles (1.3 kilometers). Zoom in on the full resolution image on a larger screen to fully appreciate the complexity of Pluto’s surface features.

3. The Smiles

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July 14, 2015: New Horizons team members Cristina Dalle Ore, Alissa Earle and Rick Binzel react to seeing the spacecraft’s last and sharpest image of Pluto before closest approach.

4. Majestic Mountains

Just 15 minutes after its closest approach to Pluto, the New Horizons spacecraft captured this near-sunset view of the rugged, icy mountains and flat ice plains extending to Pluto’s horizon. The backlighting highlights more than a dozen layers of haze in Pluto’s tenuous atmosphere. The image was taken from a distance of 11,000 miles (18,000 kilometers) to Pluto; the scene is 780 miles (1,250 kilometers) wide.

5. Icy Dunes

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Found near the mountains that encircle Pluto’s Sputnik Planitia plain, newly discovered ridges appear to have formed out of particles of methane ice as small as grains of sand, arranged into dunes by wind from the nearby mountains.

6. Glacial Plains

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The vast nitrogen ice plains of Pluto’s Sputnik Planitia – the western half of Pluto’s “heart”—continue to give up secrets. Scientists processed images of Sputnik Planitia to bring out intricate, never-before-seen patterns in the surface textures of these glacial plains.

7. Colorful and Violent Charon

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High resolution images of Pluto’s largest moon, Charon, show a surprisingly complex and violent history. Scientists expected Charon to be a monotonous, crater-battered world; instead, they found a landscape covered with mountains, canyons, landslides, surface-color variations and more.

8. Ice Volcanoes

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One of two potential cryovolcanoes spotted on the surface of Pluto by the New Horizons spacecraft. This feature, known as Wright Mons, was informally named by the New Horizons team in honor of the Wright brothers. At about 90 miles (150 kilometers) across and 2.5 miles (4 kilometers) high, this feature is enormous. If it is in fact an ice volcano, as suspected, it would be the largest such feature discovered in the outer solar system.

9. Blue Rays

Pluto’s receding crescent as seen by New Horizons at a distance of 120,000 miles (200,000 kilometers). Scientists believe the spectacular blue haze is a photochemical smog resulting from the action of sunlight on methane and other molecules in Pluto’s atmosphere. These hydrocarbons accumulate into small haze particles, which scatter blue sunlight—the same process that can make haze appear bluish on Earth.

10. Encore

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On Jan. 1, 2019, New Horizons will fly past a small Kuiper Belt Object named MU69 (nicknamed Ultima Thule)—a billion miles (1.5 billion kilometers) beyond Pluto and more than four billion miles (6.5 billion kilometers) from Earth. It will be the most distant encounter of an object in history—so far—and the second time New Horizons has revealed never-before-seen landscapes.

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Source: NASA


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10 Frequently Asked Questions About the James Webb Space Telescope

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10 Frequently Asked Questions About the James Webb Space Telescope

Got basic questions about the James Webb Space Telescope and what amazing things we’ll learn from it? We’ve got your answers right here! 

The James Webb Space Telescope, or Webb, is our upcoming infrared space observatory, which will launch in 2021. It will spy the first luminous objects that formed in the universe and shed light on how galaxies evolve, how stars and planetary systems are born, and how life could form on other planets.

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1. What is the James Webb Space Telescope?

Our James Webb Space Telescope is a giant space telescope that observes infrared light. Rather than a replacement for the Hubble Space Telescope, it’s a scientific successor that will complement and extend its discoveries.

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Being able to see longer wavelengths of light than Hubble and having greatly improved sensitivity will let Webb look further back in time to see the first galaxies that formed in the early universe, and to peer inside dust clouds where stars and planetary systems are forming today.

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2. What are the most exciting things we will learn?

We have yet to observe the era of our universe’s history when galaxies began to form

We have a lot to learn about how galaxies got supermassive black holes in their centers, and we don’t really know whether the black holes caused the galaxies to form or vice versa.

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We can’t see inside dust clouds with high resolution, where stars and planets are being born nearby, but Webb will be able to do just that. 

We don’t know how many planetary systems might be hospitable to life, but Webb could tell whether some Earth-like planets have enough water to have oceans.

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We don’t know much about dark matter or dark energy, but we expect to learn more about where the dark matter is now, and we hope to learn the history of the acceleration of the universe that we attribute to dark energy. 

And then, there are the surprises we can’t imagine!

3. Why is Webb an infrared telescope?

By viewing the universe at infrared wavelengths with such sensitivity, Webb will show us things never before seen by any other telescope. For example, it is only at infrared wavelengths that we can see the first stars and galaxies forming after the Big Bang. 

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And it is with infrared light that we can see stars and planetary systems forming inside clouds of dust that are opaque to visible light, such as in the above visible and infrared light comparison image of the Carina Nebula.

4. Will Webb take amazing pictures like Hubble? Can Webb see visible light?

YES, Webb will take amazing pictures! We are going to be looking at things we’ve never seen before and looking at things we have seen before in completely new ways.

The beauty and quality of an astronomical image depends on two things: the sharpness and the number of pixels in the camera. On both of these counts, Webb is very similar to, and in many ways better than, Hubble. 

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Additionally Webb can see orange and red visible light. Webb images will be different, but just as beautiful as Hubble’s. Above, there is another comparison of infrared and visible light Hubble images, this time of the Monkey Head Nebula.

5. What will Webb’s first targets be?

The first targets for Webb will be determined through a process similar to that used for the Hubble Space Telescope and will involve our experts, the European Space Agency (ESA), the Canadian Space Agency (CSA), and scientific community participants.

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The first engineering target will come before the first science target and will be used to align the mirror segments and focus the telescope. That will probably be a relatively bright star or possibly a star field.

6. How does Webb compare with Hubble?

Webb is designed to look deeper into space to see the earliest stars and galaxies that formed in the universe and to look deep into nearby dust clouds to study the formation of stars and planets.

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In order to do this, Webb has a much larger primary mirror than Hubble (2.5 times larger in diameter, or about 6 times larger in area), giving it more light-gathering power. It also will have infrared instruments with longer wavelength coverage and greatly improved sensitivity than Hubble

Finally, Webb will operate much farther from Earth, maintaining its extremely cold operating temperature, stable pointing and higher observing efficiency than with the Earth-orbiting Hubble.

7. What will Webb tell us about planets outside our solar system? Will it take photos of these planets?

Webb will be able to tell us the composition of the atmospheres of planets outside our solar system, aka exoplanets. It will observe planetary atmospheres through the transit technique. A transit is when a planet moves across the disc of its parent star. 

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Webb will also carry coronographs to enable photography of exoplanets (planets outside our solar system) near bright stars (if they are big and bright and far from the star), but they will be only “dots,” not grand panoramas. Coronographs block the bright light of stars, which could hide nearby objects like exoplanets.

Consider how far away exoplanets are from us, and how small they are by comparison to this distance! We didn’t even know what Pluto really looked like until we were able to send an observatory to fly right near it in 2015, and Pluto is in our own solar system!

8. Will we image objects in our own solar system?

Yes! Webb will be able to observe the planets at or beyond the orbit of Mars, satellites, comets, asteroids and objects in the distant, icy Kuiper Belt.

Many important molecules, ices and minerals have strong characteristic signatures at the wavelengths Webb can observe. 

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Webb will also monitor the weather of planets and their moons. 

Because the telescope and instruments have to be kept cold, Webb’s protective sunshield will block the inner solar system from view. This means that the Sun, Earth, Moon, Mercury, and Venus, and of course Sun-grazing comets and many known near-Earth objects cannot be observed.

9. How far back will Webb see? 

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Webb will be able to see what the universe looked like around a quarter of a billion years (possibly back to 100 million years) after the Big Bang, when the first stars and galaxies started to form.

10. When will Webb launch and how long is the mission?

Webb will launch in 2021 from French Guiana on a European Space Agency Ariane 5 rocket. 

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Webb’s mission lifetime after launch is designed to be at least 5-½ years, and could last longer than 10 years. The lifetime is limited by the amount of fuel used for maintaining the orbit, and by the possibility that Webb’s components will degrade over time in the harsh environment of space.

Looking for some more in-depth FAQs? You can find them HERE.

Learn more about the James Webb Space Telescope HERE, or follow the mission on Facebook, Twitter and Instagram.

IMAGE CREDITS
Carina Nebula: ESO/T. Preibisch
Monkey Head Nebula: NASA, ESA, the Hubble Heritage Team (STScI/AURA), and J. Hester

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Source: NASA


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A room with Earth views! 🌎 Earlier this week, astronaut Ricky…

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A room with Earth views! 🌎 Earlier this week, astronaut Ricky…

A room with Earth views! 🌎 Earlier this week, astronaut Ricky Arnold captured this spectacular view of our home planet while he was orbiting at a speed of 17,500 miles per hour. If you’re wondering where in the world this video was taken, it starts as the International Space Station is above San Francisco and moving southward through the Americas. 

Each day, the station completes 16 orbits of our home planet as the six humans living and working aboard our orbiting laboratory conduct important science and research. Their work will not only benefit life here on Earth, but will help us venture deeper into space than ever before.

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Source: NASA


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Chemical Space Gardens

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Chemical Space Gardens

You know that colorful crystal garden you grew as a kid?

Yeah, we do that in space now. 

Chemical Gardens, a new investigation aboard the International Space Station takes a classic science experiment to space with the hope of improving our understanding of gravity’s impact on their structural formation.

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Here on Earth, chemical gardens are most often used to teach students about things like chemical reactions.

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Chemical gardens form when dissolvable metal salts are placed in an aqueous solution containing anions such as silicate, borate, phosphate, or carbonate.

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Delivered to the space station aboard SpaceX’S CRS-15 cargo mission, the samples for this experiment will be processed by crew members and grown throughout Expedition 56 before returning to Earth.

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Results from this investigation could provide a better understanding of cement science and improvements to biomaterial devices used for scaffolding, for use both in space and on Earth. 

Follow the growth of the chemical garden and the hundreds of other investigations constantly orbiting above you by following @ISS_Research on Twitter.

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Source: NASA


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