Category: discovery

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Meet Parker Solar Probe, Our Mission to Touch …

In just a few weeks, we’re launching a spacecraft to get closer to the Sun than any human-made object has ever gone.

The mission, called Parker Solar Probe, is outfitted with a lineup of instruments to measure the Sun’s particles, magnetic and electric fields, solar wind and more – all to help us better understand our star, and, by extension, stars everywhere in the universe.

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Parker Solar Probe is about the size of a small car, and after launch – scheduled for no earlier than Aug. 6, 2018 – it will swing by Venus on its way to the Sun, using a maneuver called a gravity assist to draw its orbit closer to our star. Just three months after launch, Parker Solar Probe will make its first close approach to the Sun – the first of 24 throughout its seven-year mission.

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Though Parker Solar Probe will get closer and closer to the Sun with each orbit, the first approach will already place the spacecraft as the closest-ever human-made object to the Sun, swinging by at 15 million miles from its surface. This distance places it well within the corona, a region of the Sun’s outer atmosphere that scientists think holds clues to some of the Sun’s fundamental physics.

For comparison, Mercury orbits at about 36 million miles from the Sun, and the previous record holder – Helios 2, in 1976 – came within 27 million miles of the solar surface. 

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Humanity has studied the Sun for thousands of years, and our modern understanding of the Sun was revolutionized some 60 years ago with the start of the Space Age. We’ve come to understand that the Sun affects Earth in more ways than just providing heat and light – it’s an active and dynamic star that releases solar storms that influence Earth and other worlds throughout the solar system. The Sun’s activity can trigger the aurora, cause satellite and communications disruptions, and even – in extreme cases – lead to power outages.

Much of the Sun’s influence on us is embedded in the solar wind, the Sun’s constant outflow of magnetized material that can interact with Earth’s magnetic field. One of the earliest papers theorizing the solar wind was written by Dr. Gene Parker, after whom the mission is named.

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Though we understand the Sun better than we ever have before, there are still big questions left to be answered, and that’s where scientists hope Parker Solar Probe will help.  

First, there’s the coronal heating problem. This refers to the counterintuitive truth that the Sun’s atmosphere – the corona – is much, much hotter than its surface, even though the surface is millions of miles closer to the Sun’s energy source at its core. Scientists hope Parker Solar Probe’s in situ and remote measurements will help uncover the mechanism that carries so much energy up into the upper atmosphere.

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Second, scientists hope to better understand the solar wind. At some point on its journey from the Sun out into space, the solar wind is accelerated to supersonic speeds and heated to extraordinary temperatures. Right now, we measure solar wind primarily with a group of satellites clustered around Lagrange point 1, a spot in space between the Sun and Earth some 1 million miles from us. 

By the time the solar wind reaches these satellites, it has traveled about 92 million miles already, blending together the signatures that could shed light on the acceleration process. Parker Solar Probe, on the other hand, will make similar measurements less than 4 million miles from the solar surface – much closer to the solar wind’s origin point and the regions of interest.

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Scientists also hope that Parker Solar
Probe will uncover the mechanisms at work behind the acceleration of solar
energetic particles, which can reach speeds more than half as fast as the speed
of light as they rocket away from the Sun! Such particles can interfere with
satellite electronics, especially for satellites outside of Earth’s magnetic
field.

Parker
Solar Probe will launch from Space Launch Complex 37 at Cape Canaveral Air
Force Station, adjacent to NASA’s Kennedy Space Center in Florida. Because of the enormous speed required to
achieve its solar orbit, the spacecraft will launch on a United Launch Alliance Delta IV Heavy, one of the most powerful rockets in the
world.

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Stay tuned over the next few weeks to learn more about Parker Solar Probe’s science and follow along with its journey to launch. We’ll be posting updates here on Tumblr, on Twitter and Facebook, and at nasa.gov/solarprobe.

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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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Solar System 10 Things: Two Years of Juno at J…

Our Juno mission arrived at the King of Planets in July 2016. The intrepid robotic explorer has been revealing Jupiter’s secrets ever since. 

Here are 10 historic Juno mission highlights:

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1. Arrival at a Colossus

After an odyssey of almost five years and 1.7 billion miles (2.7 billion kilometers), our Juno spacecraft fired its main engine to enter orbit around Jupiter on July 4, 2016. Juno, with its suite of nine science instruments, was the first spacecraft to orbit the giant planet since the Galileo mission in the 1990s. It would be the first mission to make repeated excursions close to the cloud tops, deep inside the planet’s powerful radiation belts.

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2. Science, Meet Art

Juno carries a color camera called JunoCam. In a remarkable first for a deep space mission, the Juno team reached out to the general public not only to help plan which pictures JunoCam would take, but also to process and enhance the resulting visual data. The results include some of the most beautiful images in the history of space exploration.

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3. A Whole New Jupiter

It didn’t take long for Juno—and the science teams who hungrily consumed the data it sent home—to turn theories about how Jupiter works inside out. Among the early findings: Jupiter’s poles are covered in Earth-sized swirling storms that are densely clustered and rubbing together. Jupiter’s iconic belts and zones were surprising, with the belt near the equator penetrating far beneath the clouds, and the belts and zones at other latitudes seeming to evolve to other structures below the surface.

4. The Ultimate Classroom

The Goldstone Apple Valley Radio Telescope (GAVRT) project, a collaboration among NASA, JPL and the Lewis Center for Educational Research, lets students do real science with a large radio telescope. GAVRT data includes Jupiter observations relevant to Juno, and Juno scientists collaborate with the students and their teachers.

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5. Spotting the Spot

Measuring in at 10,159 miles (16,350 kilometers) in width (as of April 3, 2017) Jupiter’s Great Red Spot is 1.3 times as wide as Earth. The storm has been monitored since 1830 and has possibly existed for more than 350 years. In modern times, the Great Red Spot has appeared to be shrinking. In July 2017, Juno passed directly over the spot, and JunoCam images revealed a tangle of dark, veinous clouds weaving their way through a massive crimson oval.

“For hundreds of years scientists have been observing, wondering and theorizing about Jupiter’s Great Red Spot,” said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. “Now we have the best pictures ever of this iconic storm. It will take us some time to analyze all the data from not only JunoCam, but Juno’s eight science instruments, to shed some new light on the past, present and future of the Great Red Spot.”

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6. Beauty Runs Deep

Data collected by the Juno spacecraft during its first pass over Jupiter’s Great Red Spot in July 2017 indicate that this iconic feature penetrates well below the clouds. The solar system’s most famous storm appears to have roots that penetrate about 200 miles (300 kilometers) into the planet’s atmosphere.

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7. Powerful Auroras, Powerful Mysteries

Scientists on the Juno mission observed massive amounts of energy swirling over Jupiter’s polar regions that contribute to the giant planet’s powerful auroras – only not in ways the researchers expected. Examining data collected by the ultraviolet spectrograph and energetic-particle detector instruments aboard Juno, scientists observed signatures of powerful electric potentials, aligned with Jupiter’s magnetic field, that accelerate electrons toward the Jovian atmosphere at energies up to 400,000 electron volts. This is 10 to 30 times higher than the largest such auroral potentials observed at Earth. 

Jupiter has the most powerful auroras in the solar system, so the team was not surprised that electric potentials play a role in their generation. What puzzled the researchers is that despite the magnitudes of these potentials at Jupiter, they are observed only sometimes and are not the source of the most intense auroras, as they are at Earth.

8. Heat from Within

Juno scientists shared a 3D infrared movie depicting densely packed cyclones and anticyclones that permeate the planet’s polar regions, and the first detailed view of a dynamo, or engine, powering the magnetic field for any planet beyond Earth (video above). Juno mission scientists took data collected by the spacecraft’s Jovian InfraRed Auroral Mapper (JIRAM) instrument and generated a 3D fly-around of the Jovian world’s north pole. 

Imaging in the infrared part of the spectrum, JIRAM captures light emerging from deep inside Jupiter equally well, night or day. The instrument probes the weather layer down to 30 to 45 miles (50 to 70 kilometers) below Jupiter’s cloud tops.

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9. A Highly Charged Atmosphere

Powerful bolts of lightning light up Jupiter’s clouds. In some ways its lightning is just like what we’re used to on Earth. In other ways,it’s very different. For example, most of Earth’s lightning strikes near the equator; on Jupiter, it’s mostly around the poles.

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10. Extra Innings

In June, we approved an update to Juno’s science operations until July 2021. This provides for an additional 41 months in orbit around. Juno is in 53-day orbits rather than 14-day orbits as initially planned because of a concern about valves on the spacecraft’s fuel system. This longer orbit means that it will take more time to collect the needed science data, but an independent panel of experts confirmed that Juno is on track to achieve its science objectives and is already returning spectacular results. The spacecraft and all its instruments are healthy and operating nominally. ​

Read the full web version of this week’s ‘Solar System: 10 Things to Know’ article HERE

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10 Things: Calling All Pluto Lovers

June 22 marks the 40th anniversary of Charon’s discovery—the dwarf planet Pluto’s largest and first known moon. While the definition of a planet is the subject of vigorous scientific debate, this dwarf planet is a fascinating world to explore. Get to know Pluto’s beautiful, fascinating companion this week.

1. A Happy Accident

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Astronomers James Christy and Robert Harrington weren’t even looking for satellites of Pluto when they discovered Charon in June 1978 at the U.S. Naval Observatory Flagstaff Station in Arizona – only about six miles from where Pluto was discovered at Lowell Observatory. Instead, they were trying to refine Pluto’s orbit around the Sun when sharp-eyed Christy noticed images of Pluto were strangely elongated; a blob seemed to move around Pluto. 

The direction of elongation cycled back and forth over 6.39 days―the same as Pluto’s rotation period. Searching through their archives of Pluto images taken years before, Christy then found more cases where Pluto appeared elongated. Additional images confirmed he had discovered the first known moon of Pluto.

2. Forever and Always

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Christy proposed the name Charon after the mythological ferryman who carried souls across the river Acheron, one of the five mythical rivers that surrounded Pluto’s underworld. But Christy also chose it for a more personal reason: The first four letters matched the name of his wife, Charlene. (Cue the collective sigh.)

3. Big Little Moon

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Charon—the largest of Pluto’s five moons and approximately the size of Texas—is almost half the size of Pluto itself. The little moon is so big that Pluto and Charon are sometimes referred to as a double dwarf planet system. The distance between them is 12,200 miles (19,640 kilometers).

4. A Colorful and Violent History

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Many scientists on the New Horizons mission expected Charon to be a monotonous, crater-battered world; instead, they found a landscape covered with mountains, canyons, landslides, surface-color variations and more. High-resolution images of the Pluto-facing hemisphere of Charon, taken by New Horizons as the spacecraft sped through the Pluto system on July 14 and transmitted to Earth on Sept. 21, reveal details of a belt of fractures and canyons just north of the moon’s equator.

5. Grander Canyon

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This great canyon system stretches more than 1,000 miles (1,600 kilometers) across the entire face of Charon and likely around onto Charon’s far side. Four times as long as the Grand Canyon, and twice as deep in places, these faults and canyons indicate a titanic geological upheaval in Charon’s past.

6. Officially Official

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In April 2018, the International Astronomical Union—the internationally recognized authority for naming celestial bodies and their surface features—approved a dozen names for Charon’s features proposed by our New Horizons mission team. Many of the names focus on the literature and mythology of exploration.

7. Flying Over Charon

This flyover video of Charon was created thanks to images from our New Horizons spacecraft. The “flight” starts with the informally named Mordor (dark) region near Charon’s north pole. Then the camera moves south to a vast chasm, descending to just 40 miles (60 kilometers) above the surface to fly through the canyon system.

8. Strikingly Different Worlds

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This composite of enhanced color images of Pluto (lower right) and Charon (upper left), was taken by New Horizons as it passed through the Pluto system on July 14, 2015. This image highlights the striking differences between Pluto and Charon. The color and brightness of both Pluto and Charon have been processed identically to allow direct comparison of their surface properties, and to highlight the similarity between Charon’s polar red terrain and Pluto’s equatorial red terrain.

9. Quality Facetime

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Charon neither rises nor sets, but hovers over the same spot on Pluto’s surface, and the same side of Charon always faces Pluto―a phenomenon called mutual tidal locking.

10. Shine On, Charon

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Bathed in “Plutoshine,” this image from New Horizons shows the night side of Charon against a star field lit by faint, reflected light from Pluto itself on July 15, 2015.

Read the full version of this week’s ‘10 Things to Know’ article on the web HERE.

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10 Things to Know About Explorer 1, America’s …

Sixty years ago, the hopes of Cold War America soared into the night sky as a rocket lofted skyward above Cape Canaveral, a soon-to-be-famous barrier island off the Florida coast.

1. The Original Science Robot

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Sixty years ago this week, the United States sent its first satellite into space on Jan. 31, 1958. The spacecraft, small enough to be held triumphantly overhead, orbited Earth from as far as 1,594 miles (2,565 km) above and made the first scientific discovery in space. It was called, appropriately, Explorer 1.

2. Why It’s Important

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The world had changed three months before Explorer 1’s launch, when the Soviet Union lofted Sputnik into orbit on Oct. 4, 1957. That satellite was followed a month later by a second Sputnik spacecraft. All of the missions were inspired when an international council of scientists called for satellites to be placed in Earth orbit in the pursuit of science. The Space Age was on.

3. It…Wasn’t Easy

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When Explorer 1 launched, we (NASA) didn’t yet exist. It was a project of the U.S. Army and was built by Caltech’s Jet Propulsion Laboratory (JPL) in Pasadena, California. After the Sputnik launch, the Army, Navy and Air Force were tasked by President Eisenhower with getting a satellite into orbit within 90 days. The Navy’s Vanguard Rocket, the first choice, exploded on the launch pad Dec. 6, 1957.

4. The People Behind Explorer 1

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University of Iowa physicist James Van Allen, whose proposal was chosen for the Vanguard satellite, had made sure his scientific instrument—a cosmic ray detector—would fit either launch vehicle. Wernher von Braun, working with the Army Ballistic Missile Agency in Alabama, directed the design of the Redstone Jupiter-C launch rocket, while JPL Director William Pickering oversaw the design of Explorer 1 and other upper stages of the rocket. JPL was also responsible for sending and receiving communications from the spacecraft.

5. All About the Science

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Explorer 1’s science payload took up 37.25 inches (95 cm) of the satellite’s total 80.75 inches (2.05 meters). The main instruments were a cosmic-ray detector; internal, external and nose-cone temperature sensors; a micrometeorite impact microphone; a ring of micrometeorite erosion gauges; and two transmitters. There were two antennas in the body of the satellite and its four flexible whips formed a turnstile antenna that extended with the rotation of the satellite. Electrical power was provided by batteries that made up 40 percent of the total payload weight.

6. At the Center of a Space Doughnut

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The first scientific discovery in space came from Explorer 1. Earth is surrounded by radiation belts of electrons and charged particles, some of them moving at nearly the speed of light, about 186,000 miles (299,000 km) per second. The two belts are shaped like giant doughnuts with Earth at the center. Data from Explorer 1 and Explorer 3 (launched March 26, 1958) led to the discovery of the inner radiation belt, while Pioneer 3 (Dec. 6, 1958) and Explorer IV (July 26, 1958) provided additional data, leading to the discovery of the outer radiation belt. The radiation belts can be hazardous for spacecraft, but they also protect the planet from harmful particles and energy from the Sun.

7. 58,376 Orbits

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Explorer 1’s last transmission was received May 21, 1958. The spacecraft re-entered Earth’s atmosphere and burned up on March 31, 1970, after 58,376 orbits. From 1958 on, more than 100 spacecraft would fall under the Explorer designation.

8. Find Out More!

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Want to know more about Explorer 1? Check out the website and download the poster celebrating 60 years of space science. go.nasa.gov/Explorer1

9. Hold the Spacecraft In Your Hands

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Create your own iconic Explorer 1 photo (or re-create the original), with our Spacecraft 3D app. Follow @NASAEarth this week to see how we #ExploreAsOne. https://go.nasa.gov/2BmSCWi

10. What’s Next?

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All of our missions can trace a lineage to Explorer 1. This year alone, we’re going to expand the study of our home planet from space with the launch of two new satellite missions (GRACE-FO and ICESat-2); we’re going back to Mars with InSight; and the Transiting Exoplanet Survey Satellite (TESS) will search for planets outside our solar system by monitoring 200,000 bright, nearby stars. Meanwhile, the Parker Solar Probe will build on the work of James Van Allen when it flies closer to the Sun than any mission before.

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#NASARemembers

Each year we hold a Day of Remembrance. Today, Jan. 25, we pay will tribute to the crews of Apollo 1 and space shuttles Challenger and Columbia, as well as other NASA colleagues who lost their lives while furthering the cause of exploration and discovery. 

#NASARemembers

Learn more about the Day of Remembrance HERE

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Finalists for a Future Mission to Explore the …

We’ve selected two finalists for a robotic mission that is planned to launch in the mid-2020s! Following a competitive peer review process, these two concepts were chosen from 12 proposals that were submitted in April under a New Frontiers program announcement opportunity.

What are they?

In no particular order…

CAESAR

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CAESAR, or the Comet Astrobiology Exploration Sample Return mission seeks to return a sample from 67P/Churyumov-Gerasimenko – the comet that was successfully explored by the European Space Agency’s Rosetta spacecraft – to determine its origin and history.

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This mission would acquire a sample from the nucleus of comet Churyumov-Gerasimenko and return it safely to Earth. 

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Comets are made up of materials from ancient stars, interstellar clouds and the birth of our solar system, so the CAESAR sample could reveal how these materials contributed to the early Earth, including the origins of the Earth’s oceans, and of life.

Dragonfly

A drone-like rotorcraft would be sent to explore the prebiotic chemistry and habitability of dozens of sites on Saturn’s moon Titan – one of the so-called ocean worlds in our solar system.

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Unique among these Ocean Worlds, Titan has a surface rich in organic compounds and diverse environments, including those where carbon and nitrogen have interacted with water and energy.

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Dragonfly would be a dual-quadcopter lander that would take advantage of the environment on Titan to fly to multiple locations, some hundreds of miles apart, to sample materials and determine surface composition to investigate Titan’s organic chemistry and habitability, monitor atmospheric and surface conditions, image landforms to investigate geological processes, and perform seismic studies.

What’s Next?

The CAESAR and Dragonfly missions will receive funding through the end of 2018 to further develop and mature the concepts. It is planned that from these, one investigation will be chosen in the spring of 2019 to continue into subsequent mission phases.

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That mission would be the fourth mission in the New Frontiers portfolio, which conducts principal investigator (PI)-led planetary science missions under a development cost cap of approximately $850 million. Its predecessors are the New Horizons mission to Pluto and a Kuiper Belt object, the Juno mission to Jupiter and OSIRIS-REx, which will rendezvous with and return a sample of the asteroid Bennu. 

Key Technologies

We also announced that two mission concepts were chosen to receive technology development funds to prepare them for future mission opportunities.

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The Enceladus Life Signatures and Habitability (ELSAH) mission concept will receive funds to enable life detection measurements by developing cost-effective techniques to limit spacecraft contamination on cost-capped missions.

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The Venus In situ Composition Investigations (VICI) mission concept will further develop the VEMCam instrument to operate under harsh conditions on Venus. The instrument uses lasers on a lander to measure the mineralogy and elemental composition of rocks on the surface of Venus.

The call for these mission concepts occurred in April and was limited to six mission themes: comet surface sample return, lunar south pole-Aitken Basin sample return, ocean worlds, Saturn probe, Trojan asteroid tour and rendezvous and Venus insitu explorer.

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What in the Universe is an Exoplanet?

Simply put, an exoplanet is a planet that orbits another star. 

All of the planets in our solar system orbit around the Sun. Planets that orbit around other stars outside our solar system are called exoplanets.

Just because a planet orbits a star (like Earth) does not mean that it is automatically stable for life. The planet must be within the habitable zone, which is the area around a star in which water has the potential to be liquid…aka not so close that all the water would evaporate, and not too far away where all the water would freeze.

Exoplanets are very hard to see directly with telescopes. They are hidden by the bright glare of the stars they orbit. So, astronomers use other ways to detect and study these distant planets by looking at the effects these planets have on the stars they orbit.

One way to search for exoplanets is to look for “wobbly” stars. A star that has planets doesn’t orbit perfectly around its center. From far away, this off-center orbit makes the star look like it’s wobbling. Hundreds of planets have been discovered using this method. However, only big planets—like Jupiter, or even larger—can be seen this way. Smaller Earth-like planets are much harder to find because they create only small wobbles that are hard to detect.

How can we find Earth-like planets in other solar systems?

In 2009, we launched a spacecraft called Kepler to look for exoplanets. Kepler looked for planets in a wide range of sizes and orbits. And these planets orbited around stars that varied in size and temperature.

Kepler detected exoplanets using something called the transit method. When a planet passes in front of its star, it’s called a transit. As the planet transits in front of the star, it blocks out a little bit of the star’s light. That means a star will look a little less bright when the planet passes in front of it. Astronomers can observe how the brightness of the star changes during a transit. This can help them figure out the size of the planet.

By studying the time between transits, astronomers can also find out how far away the planet is from its star. This tells us something about the planet’s temperature. If a planet is just the right temperature, it could contain liquid water—an important ingredient for life.

So far, thousands of planets have been discovered by the Kepler mission.

We now know that exoplanets are very common in the universe. And future missions have been planned to discover many more!

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Human Expansion Across Solar System

On this day in 1972, two NASA astronauts landed on the Moon. Now, 45 years later, we have been instructed to return to the lunar surface.

Today at the White House, President Trump signed the Space Policy Directive 1, a change in national space policy that provides for a U.S.-led program with private sector partners for a human return to the Moon, followed by missions to Mars and beyond.

Among other dignitaries on hand for the signing, were NASA astronauts Sen. Harrison “Jack” Schmitt, Buzz Aldrin, Peggy Whitson and Christina Koch.

Schmitt landed on the moon 45 years to the minute that the policy directive was signed as part of our Apollo 17 mission, and is the most recent living person to have set foot on our lunar neighbor. 

Above, at the signing ceremony instructing us to send humans back to the lunar surface, Schmitt shows First Daughter Ivanka Trump the Moon sample he collected in 1972.

The effort signed today will more effectively organize government, private industry and international efforts toward returning humans on the Moon, and will lay the foundation that will eventually enable human exploration of Mars.

To learn more, visit: https://www.nasa.gov/press-release/new-space-policy-directive-calls-for-human-expansion-across-solar-system

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