Where we go: Part 2 of your year-end reading list

Combined image of Pluto
This high-resolution image, captured by NASA's New Horizons spacecraft, combines blue, red and infrared images taken by the Ralph/Multispectral Visual Imaging Camera (MVIC). The bright expanse is the western lobe of the "heart," informally called Sputnik Planum, which has been found to be rich in nitrogen, carbon monoxide and methane ices.

Cold War machines continue their long pedigrees of peaceful space travel to expand human reach across the solar system.

The New Horizons probe pierced the heavens on its way to Pluto atop the latest evolution of a 1950s-era inter-continental ballistic missile this year, and astronauts on their way to the International Space Station are riding atop Soyuz rockets, the latest evolution of the Russian R-7.

Soyuz Expedition 46 Launch
The Soyuz TMA-19M rocket is launched with Expedition 46 Soyuz Commander Yuri Malenchenko of the Russian Federal Space Agency (Roscosmos); Flight Engineer Tim Kopra of NASA; and Flight Engineer Tim Peake of ESA (European Space Agency) on Dec. 15 at the Baikonur Cosmodrome in Kazakhstan. Malenchenko, Kopra, and Peake will spend the next six months living and working aboard the International Space Station.
NASA | Joel Kowsky

Originally designed to carry aloft the massive nuclear warheads of the 1950s, the R-7 rocket was replaced as an ICBM when nuclear weapons began to miniaturize.

Repurposed to fly peaceful — though heavy — lift-to-orbit missions, the derivatives of the R-7 launched the Sputnik satellite and cosmonaut Yuri Gagarin. They live on to deliver humans and supplies to the International Space Station.

Expedition 45 departs ISS on Soyuz craft
The Soyuz TMA-17M spacecraft undocks, carrying crew members Oleg Kononenko, Kjell Lindgren and Kimiya Yui back to Earth.
NASA | @StationCDRKelley

Looking forward to 2016, travel to the ISS may be less routine, depending on how things shake out as Russian President Vladimir Putin's administration dissolves the Russian space agency, Roscosmos, replacing it with a new Russian space corporation.

International Space Station

Fifteen years of human habitation on the International Space Station has made the ISS a nexus of scientific study. Astronauts have been conducting a myriad of scientific experiments, some focused on answering unknown questions about what might happen to people headed for Mars.

• A year in space

In March 2015, astronaut Scott Kelly began his year in space, as part of a comparative study with his twin brother Mark, a retired astronaut, to measure the impact of long-term space flight. A multi-part video series by Time profiles the mission.

Space Lettuce

Astronauts Kimiya Yui (left), Kjell Lindgren and Scott Kelly taste the lettuce and render verdicts.

Sunset in Mars' Gale Crater
NASA's Curiosity Mars rover recorded this view of the sun setting at the close of the mission's 956th Martian day, or sol, on April 15, from the rover's location in Gale Crater, Mars.
NASA | Getty Images


As of May 2015, Mars has five active orbiters, and at least one non-functional orbiter, in the red planet neighborhood. One of these, the MAVEN probe, was able to determine how Mars was stripped of its atmosphere, mainly because of a weak magnetic field that was unable to hold the solar wind at bay.

Martian sand dunes
This view from the Mast Camera (Mastcam) on NASA's Curiosity rover shows a dark sand dune in the middle distance. The scene combines several images taken on Sept. 25 during the 1,115th Martian day, or sol, of Curiosity's work on Mars.
NASA| JPL-Caltech
NASA's Curiosity Mars rover
This low-angle self-portrait of NASA's Curiosity rover shows the vehicle at the site from which it reached down to drill into a rock target called "Buckskin." The MAHLI camera on Curiosity's robotic arm took multiple images on Aug. 5 that were stitched together into this selfie.
NASA | JPL-Caltech | MSSS

The Curiosity rover has been slowly scaling Mount Sharp, examining the layers of sedimentary rock as it makes the slow march toward the summit.

Marias Pass, Mars
This view from the Mast Camera (Mastcam) in NASA's Curiosity rover shows the "Marias Pass" area where a lower and older geological unit of mudstone -- the pale zone in the center of the image -- lies in contact with an overlying geological unit of sandstone.
NASA | JPL-Caltech | MSSS

Track the progress of Curiosity

The rover is trundling along the Martian landscape toward the summit of Mount Sharp.

Pluto & Charon

New Horizons, taking a nearly nine-year journey through the solar system, was launched atop an Atlas V 551 rocket in 2006 on a solar escape trajectory. In 2007, Jupiter and its moons served as the trial run for the probe's sensor suite as it raced by to meet Pluto.

Pluto and Charon
Pluto and Charon viewed by the New Horizons probe at a distance of nearly 13 million kilometers.

As July came around, we were greeted with a new haunting image of Pluto and Charon.

Charon and Pluto, composite image
This composite of enhanced color images of Pluto (lower right) and Charon (upper left), was taken by NASA's New Horizons spacecraft as it passed through the Pluto system on July 14. The image highlights the striking differences between Pluto and Charon. The color and brightness of both Pluto and Charon have been processed identically.

In order to collect as much data as possible New Horizons went dark, ceasing any transmissions home until after the flyby was complete. When the darkness was pierced, the data turned out to be amazing.

Composite image of pits on the surface of Pluto
This composite image reveals the intricate pattern of "pits" across a section of Pluto's prominent heart-shaped region, informally named Tombaugh Regio. The magnified view is 50-by-50 miles (80-by-80 kilometers) across.

Intricate pattern of pits on the surface

A large pattern of "pits" in Pluto's Tombaugh Regio suggest recent surface activity, due to the lack of visible impact craters compared to other regions of Pluto. NASA researchers believe these "pits" will provide hints of how the surface ice flows, interacts with the atmosphere and changes the surface of Pluto.

Pluto's moon, Charon
NASA's New Horizons captured this high-resolution enhanced color view of Charon just before closest approach on July 14. Charon's color palette is not as diverse as Pluto's; most striking is the reddish north (top) polar region, informally named Mordor Macula. Charon is 754 miles (1,214 kilometers) across; this image resolves details as small as 1.8 miles (2.9 kilometers).

Charon up close

For the first time, Pluto's moon, Charon, was available in full view to unveil a varied landscape of mountain, canyons and more.

How to reach MU69 from Pluto

As New Horizons was transmitting Plutonian data back, navigators plotted a new course to the Kuiper belt object called 2014 MU69.

In October, the first preliminary study of Pluto was published summarizing the early data returned to us about Pluto and its natural satellites.

Read Part 1