Exploring the Planets

What's New in Planetary Exploration?

 

Curiosity's Selfie

Curiosity's Selfie

Named “Curiosity,” the latest Mars rover arrived at the red planet on August 6, 2012. It landed within Gale Crater, an area rich with water-related deposits. The rover is examining and collecting soil and rock samples. Its onboard laboratory is then analyzing the samples in the hope of finding the chemical building blocks of life.

During its first year, it discovered evidence of an ancient lake environment, favorable for microbial life, within an area called “Yellow Knife Bay.” During its second year, it drove toward Mount Sharp, a major science destination, and explored the landscape along the way. During its third year, it reached Mount Sharp and proceeded to investigate its lower slopes. In its fourth year, Curiosity is continuing its climb up the mountain.

The “selfie” was created using several images taken by the MAHLI camera on the rover’s arm on August 5, 2015. The arm isn’t in the image.

NASA/JPL-Caltech/MSSS

 

Space Peanut

Space Peanut

On July 24, 2015, Asteroid 1999 JD6 flew within 7.2 million kilometers (4.5 million miles) of Earth. These radar images of it were captured at its closest approach. The asteroid is a contact binary, an asteroid with two lobes stuck together. It is about 2 kilometers (1.2 miles) long, and its shape has earned the nickname “Space Peanut.”

The radar images were created using the Deep Space Network antenna in California and the Green Bank telescope in West Virginia. The Deep Space Network antenna beamed a radar signal at the asteroid, and the Green Bank telescope received the reflection. 

There is a model of the Deep Space Network antenna in the Exploring the Planets gallery.

NASA/JPL-Caltech/GSSR

 

Rosetta Spies Jet

Rosetta Spies Jet

The Rosetta spacecraft captured this sequence of images on July 29, 2015, showing a short-lived jet erupting from the surface of comet 67P/Churyumov-Gerasimenko.

Launched in 2004, Rosetta completed a 10-year journey to the outer solar system, where it intercepted the comet in August 2014. The spacecraft is comprised of an orbiter and a lander named Philae. In November 2014, Philae landed on the comet’s nucleus. Its primary mission lasted two-and-a-half days. Rosetta will orbit the comet until the end of 2015.

Rosetta is an international mission led by the European Space Agency with support from NASA.

ESA/Rosetta/MPS

 

Pluto's Atmosphere

Pluto's Atmosphere

New Horizons captured this image of Pluto on July 15. Backlit by the Sun, the dwarf planet is dark, while its atmosphere resembles a bright halo.

Mission scientists think the atmosphere may help explain the appearance of Pluto’s surface. Within the atmosphere are two distinct layers of haze, one about 80 kilometers (50 miles) above the surface and the other at an altitude of about 50 kilometers (30 miles). Scientists believe the hazes form when ultraviolet sunlight breaks up methane gas particles, triggering the buildup of more complex hydrocarbon gases. As these hydrocarbons drift to the lower, colder parts of the atmosphere, they condense into ice particles that create the hazes. The ultraviolet sunlight then chemically converts the hazes into the dark hydrocarbons that color Pluto’s surface. 

Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

 

Pluto in False-Color

Pluto in False-Color

Mission scientists combined four images from New Horizons’ Long Range Reconnaissance Imager (LORRI) with color data from the Ralph instrument to create this enhanced color global view of Pluto. Enhanced color images help us to detect differences in the composition and texture of the dwarf planet’s surface.

Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

 

Pluto's Frozen Plains

Pluto's Frozen Plains

New Horizons captured this close-up (left) of Pluto’s surface on July 14. It reveals a large frozen plain estimated to be no more than 100 million years old. This plain is located within Pluto’s heart feature (arrow). The heart feature was informally named “Tombaugh Regio” (Tombaugh Region) after Clyde Tombaugh, who discovered Pluto in 1930.

Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

 

Kepler-452b

Kepler-452b

Kepler is an orbiting space telescope launched in 2009. It searches distant stars for Earth-like planets within a solar system's "habitable zone," an area around a star that maintains a temperature range moderate enough to allow liquid water to exist on a planet's surface. 

In 2013 two of Kepler’s four reaction wheels, which pointed the spacecraft, failed. Efforts to fix them were unsuccessful, and data collection ceased. In 2014 Kepler began a new mission. Using pressure from sunlight, mission scientists can control the spacecraft's position again, and its hunt for planets has resumed.

This artist concept is of Kepler-452b, the most similar expoplanet to Earth found to date. It orbits in the habitable zone of star similar to our Sun. Kepler-452b is about 60 percent larger than Earth and orbits its star every 385 days. The star has nearly the same temperature and mass as our Sun.

NASA/Ames/JPL-Caltech

 

Dione, Saturn's Satellite

Dione, Saturn's Satellite

On June 16, 2015, the Cassini spacecraft captured this view of Saturn’s moon Dione. It was taken 516 kilometers (321 miles) from the moon’s surface during a close flyby. Dione is a small moon, 1,123 kilometers (698 miles) in diameter, with heavily cratered terrain. The rings of Saturn are also visible at left. 

Launched in 1997, Cassini began orbiting Saturn in 2004. It completed its initial four-year mission in 2008 and its first extended mission in 2010. The spacecraft remains in orbit, continuing to study the planet and its rings and moons on its second extended mission.

NASA/JPL-Caltech/Space Science Institute

 

Philae Wakes Up

Philae Wakes Up

In November 2014, the Rosetta spacecraft’s Philae Lander landed on the nucleus of comet 67P/Churyumov-Gerasimenko. The lander’s automated harpoon system failed to work, causing Philae to bounce twice before coming safely to rest. Unfortunately, the solar-powered lander ended up in the shadow of a cliff. This “selfie” is the only image taken of the lander after touchdown. Within its two-and-a-half day primary mission, Philae completed its science data collection and transmitted the data to Earth. Then it entered hibernation due to power loss. After seven months, Philae awoke and transmitted 300 more data packets. Mission scientists eagerly await their next contact with the lander, since more than 8,000 data packets remain to be transmitted. Rosetta is an international mission led by the European Space Agency. 

ESA/ATG medialab

 

Spirit of St. Louis

Spirit of St. Louis

In late March 2015, the Mars Exploration Rover Opportunity captured this image of "Spirit of St. Louis," a very shallow crater containing a rock spire (arrow). This unusual crater was found on the western rim of Endeavour Crater. 

The rover arrived at the red planet on January 25, 2004. It landed in Eagle Crater in a region called Meridiani Planum. Over the past 11 years, Opportunity has returned more than 180,000 images and discovered multiple pieces of evidence for ancient environments with liquid water. Since 2011 the rover has been on the western rim of Endeavour Crater, and it will continue its investigations there.

NASA/JPL-Caltech/Cornell/ASU

 

New Horizons

New Horizons

New Horizons is the first spacecraft to explore Pluto and its moons. Launched in 2006 on a 4.8-billion kilometer (3-billion mile) journey, it carries seven instruments to map composition and surface features, hunt for undiscovered moons, and study Pluto’s thin atmosphere. New Horizons is scheduled to make its closest approach to Pluto on Tuesday, July 14, 2015. See the latest news: http://pluto.jhuapl.edu/

Johns Hopkins/Applied Physics Laboratory

 

Pluto and Its Moons

Pluto and Its Moons

New Horizons’ Long-Range Reconnaissance Imager (LORRI) captured this image (A) of Pluto’s moons Nix and Hydra. It is one of a series of images taken from January 27 to February 8, 2015, at distances ranging from about 201 to 186 million kilometers (125 to 115 million miles). 

On April 9, 2015, New Horizons’ Ralph color imager took this image (B) of Pluto and its largest moon, Charon. It is the first color image of the Pluto system captured by a spacecraft on approach. It was taken from a distance of about 115 million kilometers (71 million miles). 

As New Horizons gets closer to Pluto, the spacecraft will return sharper, detailed images of the dwarf planet and its system of at least five moons.

 

JHUAPL/SwRI

 

Faces of Pluto

Faces of Pluto

New Horizons’ Long-Range Reconnaissance Imager (LORRI), took these images of Pluto. These groupings compare images captured mid-April to ones from mid-May. Within that timeframe, the spacecraft became about 32 million kilometers (20 million miles) closer to the dwarf planet. Each pair of images also shows a different “face” or side of Pluto. 

The images from mid-May reveal finer detail, and the features on each face are very different, indicating a possibly complex surface geology. The later images also support the hypothesis that Pluto may have a polar cap.

JHUAPL/SwRI

 

<em>Opportunity's</em> Marathon

Opportunity's Marathon

The Mars Exploration Rover Opportunity arrived at the Red Planet on January 25, 2004.  It landed in Eagle Crater in a region called Meridiani Planum. The map reveals the rover's journey (gold line) across the Martian surface. On March 24, 2015 (Opportunity’s 3,968th Martian day, or sol) the rover had driven 42.2 kilometers (26.2 miles)—almost exactly the length of an Olympic marathon.

NASA/Jet Propulsion Laboratory-Caltech/MSSS/NMMNHS

 

Dawn Enters Orbit Around Ceres

Dawn Enters Orbit Around Ceres

Launched in 2007, NASA’s Dawn spacecraft undertook a four-year journey to reach the asteroid belt between Jupiter and Mars. Its targets, Vesta and Ceres, are the two largest bodies in the belt. In 2011 and 2012, it spent nearly 14 months studying Vesta, an asteroid as wide as the state of Arizona.

Dawn arrived at Ceres, a dwarf planet, on March 6, 2015. About 590 miles (950 kilometers) wide, it has a rounded shape that suggests a layered interior similar to Mercury and Earth. Scientists believe it has a rocky core, a thick icy mantle, and maybe an ocean hidden beneath an icy crust.

Dawn captured this image of Ceres on March 1, 2015. It was taken from about 48,000 kilometers (30,000 miles) away.

NASA/JPL-Caltech/ UCLA/MPS/DLR/IDA

 

Asteroid 2004 BL86

Asteroid 2004 BL86

On January 26, 2015, Asteroid 2004 BL86 performed a close flyby of Earth. This radar image of it was captured during the asteroid’s closest approach, at a distance of about 1.2 million kilometers (745,000 miles).

The asteroid is about 325 meters (1,100 feet) across and is orbited by a small moon (arrow). To date, the flyby was the closest performed by a known asteroid of this size. While it was close enough for Earth-based study, it wasn’t close enough to be considered a threat.

The radar image was created using data collected by NASA’s Deep Space Network in Goldstone, California.

NASA/JPL-Caltech

 

Philae Lands on Comet

Philae Lands on Comet

On November 12, 2014, the Rosetta spacecraft’s Philae Lander successfully landed on the nucleus of comet 67P/Churyumov-Gerasimenko. The landing was not without some excitement. The lander’s automated harpoon system failed to work, allowing Philae to bounce twice before coming safely to rest. This mosaic is composed of a series of images captured by Rosetta’s OSIRIS camera before, during, and after Philae’s first touchdown.

Unfortunately, the solar-powered lander ended up in the shadow of a cliff. Within its two-and-a-half day primary mission, it completed its science data collection and transmitted the data to Earth. Then it entered hibernation due to power loss. As the comet approaches the Sun there may be enough light available to wake up the lander.

Rosetta is an international mission led by the European Space Agency.

Image courtesy of ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

 

Formation of Mount Sharp

Formation of Mount Sharp

Created using data collected by three Mars orbiters, this image (top) reveals Mount Sharp in the center of Gale Crater. In 2012 the Curiosity rover landed near the foot of Mount Sharp. Its lower rock layers interested mission scientists because they may contain minerals that form in relation to water. During its third year on Mars, Curiosity finally studied the layers up close. Mission scientists discovered that Mount Sharp may have been built by sediments deposited in a large lake bed.

This diagram (bottom left) reveals how Mount Sharp may have formed billions of years ago. (A) Gale Crater was filled with layers of sediment that were deposited during wet and dry periods. The environment alternated between that of lakes, rivers, and deserts. (B) Over time the layers were eroded away, creating the mountain. Curiosity captured this image (bottom right) on August 7, 2014. This type of evenly layered rock is seen in lake-floor deposits on Earth.

Gale Crater image courtesy of NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS
Diagram courtesy of NASA/JPL-Caltech
Layered rock image courtesy of NASA/JPL-Caltech/MSSS

 

Beagle 2 Found

Beagle 2 Found

On January 16, 2015, NASA announced the discovery of Beagle 2, the United Kingdom's long-lost Mars Lander. Carried by the European Space Agency's Mars Express orbiter, Beagle 2 was released for a Christmas Day 2003 touchdown, but was never heard from after its expected landing. The lander, and some hardware ejected during descent, were found in these images taken by the Mars Reconnaissance Orbiter's high-resolution imager HiRISE.

Images courtesy of NASA/Jet Propulsion Laboratoy-Caltech/University of Arizona/University of Leicester