X-37B Space Plane: US Air Force's 4th Mystery Mission in Photos

X-37B OTV 4 Florida Landing

U.S. Air Force

On May 20, 2015, the U.S. Air Force's fourth classified X-37B space plane mission - called Orbital Test Vehicle 4 - launched into orbit from Space Launch Complex (SLC)-41 at Cape Canaveral Air Force Station, Florida. The mission landed on May 7, 2017 after a record-shattering 718 days in space. See photos from the OTV-4 mission here.

(Editor's Note: This Slideshow was updated on May 8, 2017).

Landing Approach

Secretary of the Air Force Public Affairs

A view from NASA's Shuttle Landing Facility of the X-37B's automated landing. Watch video of the landing & see our full story!

Air Force X-37B Makes OTV-Landing

U.S. Air Force

Technicians in protective gear work on the U.S. Air Force's X-37B Orbital Test Vehicle after its successful landing at NASA's Kennedy Space Center Shuttle Landing Facility in Cape Canaveral, Florida on May 7, 2017. NASA's massive Vehicle Assembly Building is visible in the distance at top right. Watch video of the landing & see our full story!

X-37B Space Plane Infographic

Karl Tate, SPACE.com

This Space.com infographic depicts the X-37B Orbital Test Vehicle is an unmanned space test vehicle for the USAF. See how the unmanned space drone works here.

Messier 44 Skywatcher View

Greg Roberts

The U.S. Air Force's X-37B space plane is visible as a streak in this image captured by satellite tracker Greg Roberts in South Africa. The X-37B is currently flying its fourth secret mission for the U.S. Air Force. Read the Full Story.

AFSPC-5 Launch on May 20, 2015 #3

United Launch Alliance

An Atlas V rocket launched the Air Force Space Command 5 (AFSPC-5) satellite for the U.S. Air Force from Cape Canaveral, Florida, on May 20, 2015. The rocket carried the X-37B Orbital Test Vehicle (OTV), also referred to as a space plane.

X-37B Space Plane 4th Launch Stage Separation

ULA

The Air Force's robotic X-37B space plane launched aboard an Atlas V rocket from Cape Canaveral, Florida, on May 20, 2015. This image shows stage separation as the rocket ascends.

AFSPC-5 Launch on May 20, 2015 #2

United Launch Alliance

An Atlas V rocket launched the Air Force Space Command 5 (AFSPC-5) satellite for the U.S. Air Force from Cape Canaveral, Florida, on May 20, 2015. The rocket carried the X-37B Orbital Test Vehicle (OTV), also referred to as a space plane.

AFSPC-5 Launch on May 20, 2015 #1

United Launch Alliance

An Atlas V rocket launched the Air Force Space Command 5 (AFSPC-5) satellite for the U.S. Air Force from Cape Canaveral, Florida, on May 20, 2015. The rocket carried the X-37B Orbital Test Vehicle (OTV), also referred to as a space plane.

Satellite-Tracking Gear

Greg Roberts

Satellite sleuth Greg Roberts of South Africa captured the X-37B space plane using this satellite-tracking gear. Read the Full Story.

A Solar-Powered Space Plane

NASA Marshall Space Flight Center

The X-37B space plane is a robotic spacecraft built for long-duration missions in orbit. The spacecraft has a payload bay the size of a pickup truck bed, and carries a solar array to generate powere during the long months in space. This image shows an artist's depiction of the X-37B in orbit.

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