Category: planets

The Hunt for New Worlds Continues with TESS

We’re getting ready to start our next mission to find new worlds! The Transiting Exoplanet Survey Satellite (TESS) will find thousands of planets beyond our solar system for us to study in more detail. It’s preparing to launch from our Kennedy Space Center at Cape Canaveral in Florida.

image

Once it launches, TESS will look for new planets that orbit bright stars relatively close to Earth. We’re expecting to find giant planets, like Jupiter, but we’re also predicting we’ll find Earth-sized planets. Most of those planets will be within 300 light-years of Earth, which will make follow-up studies easier for other observatories.

image

TESS will find these new exoplanets by looking for their transits. A transit is a temporary dip in a star’s brightness that happens with predictable timing when a planet crosses between us and the star. The information we get from transits can tell us about the size of the planet relative to the size of its star. We’ve found nearly 3,000 planets using the transit method, many with our Kepler space telescope. That’s over 75% of all the exoplanets we’ve found so far!

image

TESS will look at nearly the entire sky (about 85%) over two years. The mission divides the sky into 26 sectors. TESS will look at 13 of them in the southern sky during its first year before scanning the northern sky the year after.

image

What makes TESS different from the other planet-hunting missions that have come before it? The Kepler mission (yellow) looked continually at one small patch of sky, spotting dim stars and their planets that are between 300 and 3,000 light-years away. TESS (blue) will look at almost the whole sky in sections, finding bright stars and their planets that are between 30 and 300 light-years away.

image

TESS will also have a brand new kind of orbit (visualized below). Once it reaches its final trajectory, TESS will finish one pass around Earth every 13.7 days (blue), which is half the time it takes for the Moon (gray) to orbit. This position maximizes the amount of time TESS can stare at each sector, and the satellite will transmit its data back to us each time its orbit takes it closest to Earth (orange).

image

Kepler’s goal was to figure out how common Earth-size planets might be. TESS’s mission is to find exoplanets around bright, nearby stars so future missions, like our James Webb Space Telescope, and ground-based observatories can learn what they’re made of and potentially even study their atmospheres. TESS will provide a catalog of thousands of new subjects for us to learn about and explore.

image

The TESS mission is led by MIT and came together with the help of many different partners. Learn more about TESS and how it will further our knowledge of exoplanets, or check out some more awesome images and videos of the spacecraft. And stay tuned for more exciting TESS news as the spacecraft launches!

Watch the Launch + More!

image

Sunday, April 15
11 a.m. EDT – NASA Social Mission Overview

Join mission experts to learn more about TESS, how it will search for worlds beyond our solar system and what scientists hope to find! Have questions? Use #askNASA to have them answered live during the broadcast.

Watch HERE


1 p.m. EDT – Prelaunch News Conference

Get an update on the spacecraft, the rocket and the liftoff operations ahead of the April 16 launch! Have questions? Use #askNASA to have them answered live during the broadcast.

Watch HERE.


3 p.m. EDT – Science News Conference

Hear from mission scientists and experts about the science behind the TESS mission. Have questions? Use #askNASA to have them answered live during the broadcast. 

Watch HERE.


4 p.m. EDT – TESS Facebook Live

This live show will dive into the science behind the TESS spacecraft, explain how we search for planets outside our solar system and will allow you to ask your questions to members of the TESS team. 

Watch HERE


Monday, April 16
10 a.m. EDT – NASA EDGE: TESS Facebook Live

This half-hour live show will discuss the TESS spacecraft, the science of searching for planets outside our solar system, and the launch from Cape Canaveral.

Watch HERE.

1 p.m. EDT – Reddit AMA

Join us live on Reddit for a Science AMA to discuss the hunt for exoplanets and the upcoming launch of TESS!

Join in HERE.


6 p.m. EDT – Launch Coverage!

TESS is slated to launch at 6:32 p.m. EDT on a SpaceX Falcon 9 rocket from our Kennedy Space Center in Florida.

Watch HERE.

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

Solar System: 10 Things to Know This Week

Planets Outside Our Solar System

Let the planet-hunting begin!

Our Transiting Exoplanet Survey Satellite (TESS), which will scan the skies to look for planets beyond our solar system—known as exoplanets—is now in Florida to begin preparations for launch in April. Below, 10 Things to know about the many, many unknown planets out there awaiting our discovery.

1Exo-what?

We call planets in our solar system, well, planets, but the many planets we’re starting to discover outside of our solar system are called exoplanets. Basically, they’re planets that orbit another star.

2All eyes on TRAPPIST-1.

Remember the major 2016 announcement that we had discovered seven planets 40 light-years away, orbiting a star called TRAPPIST-1? Those are all exoplanets. (Here’s a refresher.)

3Add 95 new ones to that.

Just last month, our Kepler telescope discovered 95 new exoplanets beyond our solar system (on top of the thousands of exoplanets Kepler has discovered so far). The total known planet count beyond our solar system is now more than 3,700. The planets range in size from mostly rocky super-Earths and fluffy mini-Neptunes, to Jupiter-like giants. They include a new planet orbiting a very bright star—the brightest star ever discovered by Kepler to have a transiting planet.

4Here comes TESS.

How many more exoplanets are out there waiting to be discovered? TESS will monitor more than 200,000 of the nearest and brightest stars in search of transit events—periodic dips in a star’s brightness caused by planets passing in front—and is expected to find thousands of exoplanets.

5With a sidekick, too.

Our upcoming James Webb Space Telescope, will provide important follow-up observations of some of the most promising TESS-discovered exoplanets. It will also allow scientists to study their atmospheres and, in some special cases, search for signs that these planets could support life.

6Prepped for launch.

TESS is scheduled to launch on a SpaceX Falcon 9 rocket from Cape Canaveral Air Force Station nearby our Kennedy Space Center in Florida, no earlier than April 16, pending range approval.

7A groundbreaking find.

In 1995, 51 Pegasi b (also called “Dimidium”) was the first exoplanet discovered orbiting a star like our Sun. This find confirmed that planets like the ones in our solar system could exist elsewhere in the universe.

8Trillions await.

A recent statistical estimate places, on average, at least one planet around every star in the galaxy. That means there could be a trillion planets in our galaxy alone, many of them in the range of Earth’s size.

9Signs of life.

Of course, our ultimate science goal is to find unmistakable signs of current life. How soon can that happen? It depends on two unknowns: the prevalence of life in the galaxy and a bit of luck. Read more about the search for life.

10Want to explore the galaxy?

No need to be an astronaut. Take a trip outside our solar system with help from our Exoplanet Travel Bureau.

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

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

Solar System: 10 Things to Know This Week

Week of March 5: Great Shots
Inspiring views of our solar system and beyond

1-Mars-By-Numbers

image

“The first TV image of Mars, hand colored strip-by-strip, from Mariner 4 in 1965. The completed image was framed and presented to JPL director, William H. Pickering. Truly a labor of love for science!” -Kristen Erickson, NASA Science Engagement and Partnerships Director

2-Night Life

image

“There are so many stories to this image. It is a global image, but relates to an individual in one glance. There are stories on social, economic, population, energy, pollution, human migration, technology meets science, enable global information, etc., that we can all communicate with similar interests under one image.” -Winnie Humberson, NASA Earth Science Outreach Manager

3-Pale Blue Dot

image

“Whenever I see this picture, I wonder…if another species saw this blue dot what would they say and would they want to discover what goes on there…which is both good and bad. However, it would not make a difference within the eternity of space—we’re so insignificant…in essence just dust in the galactic wind—one day gone forever.”

-Dwayne Brown, NASA Senior Communications Official

4-Grand Central

image

“I observed the Galactic Center with several X-ray telescopes before Chandra, including the Einstein Observatory and ROSAT. But the Chandra image looks nothing like those earlier images, and it reminded me how complex the universe really is. Also I love the colors.” -Paul Hertz, Director, NASA Astrophysics Division

5-Far Side Photobomb

image

“This image from the Deep Space Climate Observatory (DSCOVR) satellite captured a unique view of the Moon as it moved in front of the sunlit side of Earth in 2015. It shows a view of the farside of the Moon, which faces the Sun, that is never directly visible to us here on Earth. I found this perspective profoundly moving and only through our satellite views could this have been shared.” -Michael Freilich, Director NASA Earth Science Division

6-”Shocking, Exciting and Wonderful”

image

“Pluto was so unlike anything I could imagine based on my knowledge of the Solar System. It showed me how much about the outer solar system we didn’t know. Truly shocking, exciting and wonderful all at the same time.” -Jim Green, Director, NASA Planetary Science Division

7-Slices of the Sun

image

“This is an awesome image of the Sun through the Solar Dynamic Observatory’s many filters. It is one of my favorites.” – Peg Luce, Director, NASA Heliophysics Division (Acting)

8-Pluto’s Cold, Cold Heart

image

“This high-resolution, false color image of Pluto is my favorite. The New Horizons flyby of Pluto on July 14, 2015 capped humanity’s initial reconnaissance of every major body in the solar system. To think that all of this happened within our lifetime! It’s a reminder of how privileged we are to be alive and working at NASA during this historic era of space exploration.” – Laurie Cantillo, NASA Planetary Science Public Affairs Officer

9-Family Portrait

image

“The Solar System family portrait, because it is a symbol what NASA exploration is really about: Seeing our world in a new and bigger way.” – Thomas H. Zurbuchen, Associate Administrator, NASA Science Mission Directorate

10-Share Your Favorite Space Shots

image

Tag @NASASolarSystem on your favorite social media platform with a link to your favorite image and few words about why it makes your heart thump.

Check out the full version of this article HERE.

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

What’s Up – March 2018

What’s Up For March?

Several Planets and the Zodiacal Light!

image

This month, at sunset, catch elusive Mercury, bright Venus, the Zodiacal Light, Mars, Saturn and Jupiter between midnight and dawn!

image

Both Venus and Mercury play the part of “evening stars” this month. At the beginning of the month they appear low on the western horizon.

image

The Moon itself joins the pair from March 18th through the 20th. 

image

The Moon skims by the Pleiades star cluster and Taurus’s bright red star Aldebaran on the next few evenings, March 21 through the 23rd.

image

Jupiter, king of the planets, rises just before midnight this month and earlier by month end. 

image

Even through the smallest telescope or average binoculars, you should see the 4 Galilean moons, Europa, Io, Callisto and Ganymede.

image

The March morning sky offers dazzling views of Mars and Saturn all month long.

image

Through a telescope, you can almost make out some of the surface features on Mars.

image

Look a little farther into Mars’ future and circle May 5th with a red marker. When our InSight spacecraft launches for its 6 month journey to the Red Planet, Mars will be easily visible to your unaided eye. 

image

Keep watching Mars as it travels closer to Earth. It will be closest in late July, when the red planet will appear larger in apparent diameter than it has since 2003!

image

You are in for a real treat if you can get away to a dark sky location on a moonless night this month – the Zodiacal Light and the Milky Way intersect! 

image

The Zodiacal light is a faint triangular glow seen from a dark sky just after sunset in the spring or just before sunrise in the fall.

image

The more familiar Milky Way is one of the spiral arms of our galaxy. 

image

What we’re seeing is sunlight reflecting off dust grains that circle the Sun in the inner solar system. These dust grains journey across our sky in the ecliptic, the same plane as the Moon and the planets.

Watch the full What’s Up for March Video: 

There are so many sights to see in the sky. To stay informed, subscribe to our What’s Up video series on Facebook.

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

Solar System: 10 Things to Know This Week

Pioneer Days

Someone’s got to be first. In space, the first explorers beyond Mars were Pioneers 10 and 11, twin robots who charted the course to the cosmos.

image

1-Before Voyager

image

Voyager, with its outer solar system tour and interstellar observations, is often credited as the greatest robotic space mission. But today we remember the plucky Pioneers, the spacecraft that proved Voyager’s epic mission was possible.

2-Where No One Had Gone Before

image

Forty-five years ago this week, scientists still weren’t sure how hard it would be to navigate the main asteroid belt, a massive field of rocky debris between Mars and Jupiter. Pioneer 10 helped them work that out, emerging from first the first six-month crossing in February 1973. Pioneer 10 logged a few meteoroid hits (fewer than expected) and taught engineers new tricks for navigating farther and farther beyond Earth.

3-Trailblazer No. 2

image

Pioneer 11 was a backup spacecraft launched in 1973 after Pioneer 10 cleared the asteroid belt. The new mission provided a second close look at Jupiter, the first close-up views of Saturn and also gave Voyager engineers plotting an epic multi-planet tour of the outer planets a chance to practice the art of interplanetary navigation.

4-First to Jupiter

image

Three-hundred and sixty-three years after humankind first looked at Jupiter through a telescope, Pioneer 10 became the first human-made visitor to the Jovian system in December 1973. The spacecraft spacecraft snapped about 300 photos during a flyby that brought it within 81,000 miles (about 130,000 kilometers) of the giant planet’s cloud tops.

5-Pioneer Family

image

Pioneer began as a Moon program in the 1950s and evolved into increasingly more complicated spacecraft, including a Pioneer Venus mission that delivered a series of probes to explore deep into the mysterious toxic clouds of Venus. A family portrait (above) showing (from left to right) Pioneers 6-9, 10 and 11 and the Pioneer Venus Orbiter and Multiprobe series. Image date: March 11, 1982. 

6-A Pioneer and a Pioneer

image

Classic rock has Van Halen, we have Van Allen. With credits from Explorer 1 to Pioneer 11, James Van Allen was a rock star in the emerging world of planetary exploration. Van Allen (1914-2006) is credited with the first scientific discovery in outer space and was a fixture in the Pioneer program. Van Allen was a key part of the team from the early attempts to explore the Moon (he’s pictured here with Pioneer 4) to the more evolved science platforms aboard Pioneers 10 and 11.

7-The Farthest…For a While

image

For more than 25 years, Pioneer 10 was the most distant human-made object, breaking records by crossing the asteroid belt, the orbit of Jupiter and eventually even the orbit of Pluto. Voyager 1, moving even faster, claimed the most distant title in February 1998 and still holds that crown.

8-Last Contact

image

We last heard from Pioneer 10 on Jan. 23, 2003. Engineers felt its power source was depleted and no further contact should be expected. We tried again in 2006, but had no luck. The last transmission from Pioneer 11 was received in September 1995. Both missions were planned to last about two years.

9-Galactic Ghost Ships

image

Pioneers 10 and 11 are two of five spacecraft with sufficient velocity to escape our solar system and travel into interstellar space. The other three—Voyagers 1 and 2 and New Horizons—are still actively talking to Earth. The twin Pioneers are now silent. Pioneer 10 is heading generally for the red star Aldebaran, which forms the eye of Taurus (The Bull). It will take Pioneer over 2 million years to reach it. Pioneer 11 is headed toward the constellation of Aquila (The Eagle) and will pass nearby in about 4 million years.

10-The Original Message to the Cosmos

image

Years before Voyager’s famed Golden Record, Pioneers 10 and 11 carried the original message from Earth to the cosmos. Like Voyager’s record, the Pioneer plaque was the brainchild of Carl Sagan who wanted any alien civilization who might encounter the craft to know who made it and how to contact them. The plaques give our location in the galaxy and depicts a man and woman drawn in relation to the spacecraft.

Read the full version of this week’s 10 Things article HERE

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

Help Explore Your Own Solar Neighborhood

We’re always making amazing discoveries about the farthest reaches of our universe, but there’s also plenty of unexplored territory much closer to home.

image

Our “Backyard Worlds: Planet 9” is a citizen science project that asks curious people like you — yes, you there! — to help us spot objects in the area around our own solar system like brown dwarfs. You could even help us figure out if our solar system hosts a mysterious Planet 9!

image

In 2009, we launched the Wide-field Infrared Survey Explorer (WISE). Infrared radiation is a form of light that humans can’t see, but WISE could. It scans the sky for infrared light, looking for galaxies, stars and asteroids. Later on, scientists started using it to search for near-Earth objects (NEOWISE) like comets and asteroids.

image

These searches have already turned up so much data that researchers have trouble hunting through all of it. They can’t do it on their own. That’s why we asked everyone to chip in. If you join Backyard Worlds: Planet 9, you’ll learn how to look at noisy images of space and spot previously unidentified objects

You’ll figure out how to tell the difference between real objects, like planets and stars, and artifacts. Artifacts are blurry blobs of light that got scattered around in WISE’s instruments while it was looking at the sky. These “optical ghosts” sometimes look like real objects.

image

Why can’t we use computers to do this, you ask? Well, computers are good at lots of things, like crunching numbers. But when it comes to recognizing when something’s a ghostly artifact and when it’s a real object, humans beat software all the time. After some practice, you’ll be able to recognize which objects are real and which aren’t just by watching them move!

image

One of the things our citizen scientists look for are brown dwarfs, which are balls of gas too big to be planets and too small to be stars. These objects are some of our nearest neighbors, and scientists think there’s probably a bunch of them floating around nearby, we just haven’t been able to find all of them yet. 

But since Backyard Worlds launched on February 15, 2016, our volunteers have spotted 432 candidate brown dwarfs. We’ve been able to follow up 20 of these with ground-based telescopes so far, and 17 have turned out to be real!

image

Image Credit: Ryan Trainor, Franklin and Marshall College

How do we know for sure that we’ve spotted actual, bona fide, authentic brown dwarfs? Well, like with any discovery in science, we followed up with more observation. Our team gets time on ground-based observatories like the InfraRed Telescope Facility in Hawaii, the Magellan Telescope in Chile (pictured above) and the Apache Point Observatory in New Mexico and takes a closer look at our candidates. And sure enough, our participants found 17 brown dwarfs!

image

But we’re not done! There’s still lots of data to go through. In particular, we want your help looking for a potential addition to our solar system’s census: Planet 9. Some scientists think it’s circling somewhere out there past Pluto. No one has seen anything yet, but it could be you! Or drop by and contribute to our other citizen science projects like Disk Detective.

Congratulations to the citizen scientists who spotted these 17 brown dwarfs:
Dan Caselden, Rosa Castro, Guillaume Colin, Sam Deen, Bob Fletcher, Sam Goodman, Les Hamlet, Khasan Mokaev, Jörg Schümann and Tamara Stajic.

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

Jupiter’s vibrant bands of light belts and dar…

Jupiter’s vibrant bands of light belts and dark regions appear primed for their close-up during our Juno spacecraft’s 10th flyby on Feb. 7. This flyby was a gravity science positioned pass. During orbits that highlight gravity experiments, Juno is positioned toward Earth in a way that allows both transmitters to downlink data in real-time to one of the antennas of our Deep Space Network. All of Juno’s science instruments and the spacecraft’s JunoCam were in operation during the flyby, collecting data that is now being returned to Earth. The science behind this beautifully choreographed image will help us understand the origin and structure of the planet beneath those lush, swirling clouds.

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

Solar System: 10 Things to Know This Week

January 8: Images for Your Computer or Phone Wallpaper

Need some fresh perspective? Here are 10 vision-stretching images for your computer desktop or phone wallpaper. These are all real pictures, sent recently by our planetary missions throughout the solar system. You’ll find more of our images at solarsystem.nasa.gov/galleries, images.nasa.gov and www.jpl.nasa.gov/spaceimages.

Applying Wallpaper:
1. Click on the screen resolution you would like to use.
2. Right-click on the image (control-click on a Mac) and select the option ‘Set the Background’ or ‘Set as Wallpaper’ (or similar).

1. The Fault in Our Mars

image

This image from our Mars Reconnaissance Orbiter (MRO) of northern Meridiani Planum shows faults that have disrupted layered deposits. Some of the faults produced a clean break along the layers, displacing and offsetting individual beds.

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334

2. Jupiter Blues

image

Our Juno spacecraft captured this image when the spacecraft was only 11,747 miles (18,906 kilometers) from the tops of Jupiter’s clouds – that’s roughly as far as the distance between New York City and Perth, Australia. The color-enhanced image, which captures a cloud system in Jupiter’s northern hemisphere, was taken on Oct. 24, 2017, when Juno was at a latitude of 57.57 degrees (nearly three-fifths of the way from Jupiter’s equator to its north pole) and performing its ninth close flyby of the gas giant planet.

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334

3. A Farewell to Saturn

image

After more than 13 years at Saturn, and with its fate sealed, our Cassini spacecraft bid farewell to the Saturnian system by firing the shutters of its wide-angle camera and capturing this last, full mosaic of Saturn and its rings two days before the spacecraft’s dramatic plunge into the planet’s atmosphere on Sept. 15, 2017.

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334

4. All Aglow

image

Saturn’s moon Enceladus drifts before the rings, which glow brightly in the sunlight. Beneath its icy exterior shell, Enceladus hides a global ocean of liquid water. Just visible at the moon’s south pole (at bottom here) is the plume of water ice particles and other material that constantly spews from that ocean via fractures in the ice. The bright speck to the right of Enceladus is a distant star. This image was taken in visible light with the Cassini spacecraft narrow-angle camera on Nov. 6, 2011.

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334

5. Rare Encircling Filament

image

Our Solar Dynamics Observatory came across an oddity this week that the spacecraft has rarely observed before: a dark filament encircling an active region (Oct. 29-31, 2017). Solar filaments are clouds of charged particles that float above the Sun, tethered to it by magnetic forces. They are usually elongated and uneven strands. Only a handful of times before have we seen one shaped like a circle. (The black area to the left of the brighter active region is a coronal hole, a magnetically open region of the Sun).

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334 

6. Jupiter’s Stunning Southern Hemisphere

image

See Jupiter’s southern hemisphere in beautiful detail in this image taken by our Juno spacecraft. The color-enhanced view captures one of the white ovals in the “String of Pearls,” one of eight massive rotating storms at 40 degrees south latitude on the gas giant planet. The image was taken on Oct. 24, 2017, as Juno performed its ninth close flyby of Jupiter. At the time the image was taken, the spacecraft was 20,577 miles (33,115 kilometers) from the tops of the clouds of the planet.

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334

7. Saturn’s Rings: View from Beneath

image

Our Cassini spacecraft obtained this panoramic view of Saturn’s rings on Sept. 9, 2017, just minutes after it passed through the ring plane. The view looks upward at the southern face of the rings from a vantage point above Saturn’s southern hemisphere.

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334

8. From Hot to Hottest

image

This sequence of images from our Solar Dynamics Observatory shows the Sun from its surface to its upper atmosphere all taken at about the same time (Oct. 27, 2017). The first shows the surface of the sun in filtered white light; the other seven images were taken in different wavelengths of extreme ultraviolet light. Note that each wavelength reveals somewhat different features. They are shown in order of temperature, from the first one at about 11,000 degrees Fahrenheit (6,000 degrees Celsius) on the surface, out to about 10 million degrees in the upper atmosphere. Yes, the sun’s outer atmosphere is much, much hotter than the surface. Scientists are getting closer to solving the processes that generate this phenomenon.

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334

9. High Resolution View of Ceres

image

This orthographic projection shows dwarf planet Ceres as seen by our Dawn spacecraft. The projection is centered on Occator Crater, home to the brightest area on Ceres. Occator is centered at 20 degrees north latitude, 239 degrees east longitude.

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334 

10. In the Chasm

image

This image from our Mars Reconnaissance Orbiter shows a small portion of the floor of Coprates Chasma, a large trough within the Valles Marineris system of canyons. Although the exact sequence of events that formed Coprates Chasma is unknown, the ripples, mesas, and craters visible throughout the terrain point to a complex history involving multiple mechanisms of erosion and deposition. The main trough of Coprates Chasma ranges from 37 miles (60 kilometers) to 62 miles (100 kilometers) in width.

Desktop: 1280 x 800 | 1600 x 1200 | 1920 x 1200
Mobile: 1440 x 2560 | 1080 x 1920 | 750 x 1334

Explore and learn more about our solar system at: solarsystem.nasa.gov/

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

Are we alone in the universe?

There’s never been a better time to ponder this age-old question. We now know of thousands of exoplanets – planets that orbit stars elsewhere in the universe.

image

So just how many of these planets could support life?

Scientists from a variety of fields — including astrophysics, Earth science, heliophysics and planetary science — are working on this question. Here are a few of the strategies they’re using to learn more about the habitability of exoplanets.

Squinting at Earth

Even our best telescopic images of exoplanets are still only a few pixels in size. Just how much information can we extract from such limited data? That’s what Earth scientists have been trying to figure out.

One group of scientists has been taking high-resolution images of Earth from our Earth Polychromatic Imaging Camera and ‘degrading’ them in order to match the resolution of our pixelated exoplanet images. From there, they set about a grand process of reverse-engineering: They try to extract as much accurate information as they can from what seems — at first glance — to be a fairly uninformative image.

image

Credits: NOAA/NASA/DSCOVR

So far, by looking at how Earth’s brightness changes when land versus water is in view, scientists have been able to reverse-engineer Earth’s albedo (the proportion of solar radiation it reflects), its obliquity (the tilt of its axis relative to its orbital plane), its rate of rotation, and even differences between the seasons. All of these factors could potentially influence a planet’s ability to support life.

Avoiding the “Venus Zone”

In life as in science, even bad examples can be instructive. When it comes to habitability, Venus is a bad example indeed: With an average surface temperature of 850 degrees Fahrenheit, an atmosphere filled with sulfuric acid, and surface pressure 90 times stronger than Earth’s, Venus is far from friendly to life as we know it.

image

The surface of Venus, imaged by Soviet spacecraft Venera 13 in March 1982

Since Earth and Venus are so close in size and yet so different in habitability, scientists are studying the signatures that distinguish Earth from Venus as a tool for differentiating habitable planets from their unfriendly look-alikes.

Using data from our Kepler Space Telescope, scientists are working to define the “Venus Zone,” an area where planetary insolation – the amount of light a given planet receives from its host star – plays a key role in atmospheric erosion and greenhouse gas cycles.

image

Planets that appear similar to Earth, but are in the Venus Zone of their star, are, we think, unlikely to be able to support life.

Modeling Star-Planet Interactions

When you don’t know one variable in an equation, it can help to plug in a reasonable guess and see how things work out. Scientists used this process to study Proxima b, our closest exoplanet neighbor. We don’t yet know whether Proxima b, which orbits the red dwarf star Proxima Centauri four light-years away, has an atmosphere or a magnetic field like Earth’s. However, we can estimate what would happen if it did.

The scientists started by calculating the radiation emitted by Proxima Centauri based on observations from our Chandra X-ray Observatory. Given that amount of radiation, they estimated how much atmosphere Proxima b would be likely to lose due to ionospheric escape — a process in which the constant outpouring of charged stellar material strips away atmospheric gases.

image

With the extreme conditions likely to exist at Proxima b, the planet could lose the equivalent of Earth’s entire atmosphere in 100 million years — just a fraction of Proxima b’s 4-billion-year lifetime. Even in the best-case scenario, that much atmospheric mass escapes over 2 billion years. In other words, even if Proxima b did at one point have an atmosphere like Earth, it would likely be long gone by now.

Imagining Mars with a Different Star

We think Mars was once habitable, supporting water and an atmosphere like Earth’s. But over time, it gradually lost its atmosphere – in part because Mars, unlike Earth, doesn’t have a protective magnetic field, so Mars is exposed to much harsher radiation from the Sun’s solar wind.

image

But as another rocky planet at the edge of our solar system’s habitable zone, Mars provides a useful model for a potentially habitable planet. Data from our Mars Atmosphere and Volatile Evolution, or MAVEN, mission is helping scientists answer the question: How would Mars have evolved if it were orbiting a different kind of star?

Scientists used computer simulations with data from MAVEN to model a Mars-like planet orbiting a hypothetical M-type red dwarf star. The habitable zone of such a star is much closer than the one around our Sun.

image

Being in the habitable zone that much closer to a star has repercussions. In this imaginary situation, the planet would receive about 5 to 10 times more ultraviolet radiation than the real Mars does, speeding up atmospheric escape to much higher rates and shortening the habitable period for the planet by a factor of about 5 to 20.

These results make clear just how delicate a balance needs to exist for life to flourish. But each of these methods provides a valuable new tool in the multi-faceted search for exoplanet life.  Armed with these tools, and bringing to bear a diversity of scientific perspectives, we are better positioned than ever to ask: are we alone?

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

Researchers Just Found (For The First Time) An…

image

Our Milky Way galaxy is full of hundreds of billions of
worlds just waiting to be found. In 2014, scientists using data from our planet-hunting
Kepler space telescope discovered seven planets orbiting Kepler-90, a Sun-like star
located 2,500 light-years away. Now, an eighth planet has been identified in this
planetary system, making it tied with our own solar system in having the highest
number of known planets. Here’s what you need to know:

The new planet is called Kepler-90i.

image

Kepler-90i is a sizzling hot, rocky planet. It’s the smallest of eight planets in the Kepler-90 system. It orbits so close to its star that a “year” passes in just 14 days.

image

Average surface temperatures on Kepler-90i are estimated to hover around 800 degrees Fahrenheit, making it an unlikely place for life as we know it.

Its planetary system is like a scrunched up version of our solar system.

image

The Kepler-90 system is set up like our solar system, with the small planets located close to their star and the big planets farther away. This pattern is evidence that the system’s outer gas planets—which are about the size of Saturn and Jupiter—formed in a way similar to our own.

image

But the orbits are much more compact. The orbits of all eight
planets could fit within the distance of Earth’s orbit around our Sun! Sounds
crowded, but think of it this way: It would make for some great planet-hopping.

Kepler-90i was discovered using machine learning.

image

Most planets beyond our solar system are too far away to be imaged directly. The Kepler space telescope searches for these exoplanets—those planets orbiting stars beyond our solar system—by measuring how the brightness of a star changes when a planet transits, or crosses in front of its disk. Generally speaking, for a given star, the greater the dip in brightness, the bigger the planet!

image

Researchers trained a computer to learn how to identify the faint signal of transiting exoplanets in Kepler’s vast archive of deep-space data. A search for new worlds around 670 known multiple-planet systems using this machine-learning technique yielded not one, but two discoveries: Kepler-90i and Kepler-80g. The latter is part of a six-planet star system located 1,000 light-years away.

This
is just the beginning of a new way of planet hunting.

image

Kepler-90 is the first known star system besides our own that has eight planets, but scientists say it won’t be the last. Other planets may lurk around stars surveyed by Kepler. Next, researchers are using machine learning with sophisticated computer algorithms to search for more planets around 150,000 stars in the Kepler database.

In
the meantime, we’ll be doing more searching with telescopes.

image

Kepler is the most successful planet-hunting spacecraft to date, with more than 2,500 confirmed exoplanets and many more awaiting verification. Future space missions, like the Transiting Exoplanet Survey Satellite (TESS), the James Webb Space Telescope and Wide-Field Infrared Survey Telescope (WFIRST) will continue the search for new worlds and even tell us which ones might offer promising homes for extraterrestrial life.

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

*All images of exoplanets
are artist illustrations.