Spaceflight is inherently risky, and success is never assured. Case in point: on Tuesday an unmanned Russian cargo spacecraft failed in its attempt to dock with the International Space Station, the Associated Press reported. The craft was expected to try again on Sunday, after engineers try to figure out what went wrong.

Embarrassing? Yes. But in the 55 years since Sputnik blasted into orbit to inaugurate the space age, space agencies have endured bigger black eyes.

Leaving aside fatal accidents like the Challenger and Columbia space shuttle disasters, NASA has weathered some very embarrassing moments: Satellites that inexplicably fell silent. Unmanned spacecraft that became marooned in orbit--or crashed to earth. Craft that returned safely to earth--only to be lost at sea. Planetary probes that...well, you get the picture.

And if NASA has gotten its share of shiners (along with many glorious successes), so have other national space agencies. The European Space Agency (ESA), the Soviet Union (and now Russia), Japan, South Korea, and North Korea have all had their own embarrassments.

Want to see the biggest space agency black eyes ever? Keep clicking to see our fascinating photo gallery...

Correction: A previous version of this story referred to the Challenger and Discovery disasters. In fact, it was the shuttle Columbia, not Discovery, that was lost.

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  • Liberty Bell 7 Sinks

    After the second manned space mission in 1961, the Liberty Bell 7 capsule was afloat in the Atlantic ocean, awaiting recovery. Astronaut Gus Grissom reported that he heard a dull thud as the hatch blew open--the module began filling with water, and Grissom had to struggle to escape before it sank. Did Grissom "screw the pooch," as Tom Wolfe famously wrote in <i>The Right Stuff</i>? Or was there a mechanical malfunction? The world may never know.

  • Phobos-Grunt Disintegrates

    Phobos-Grunt was a 2011 Russian mission to return a sample of soil from Mars' moon Phobos. It would have been the first such sample ever returned to earth. Because of a malfunction in the craft's propulsion system, however, Phobos-Grunt never made it out of low-earth orbit. It remained there, crippled, until early 2012, when its orbit decayed and it disintegrated in the atmosphere off the coast of Chile.

  • Mars Climate Orbiter Burns Up

    This 1998 orbiter mission was supposed to study Mars' climate history and determine if the planet ever held life-sustaining water. But the $125 million craft never made it to Mars, burning up in the atmosphere on the day it was supposed to enter orbit. What caused the costly incident? One team of engineers had performed their calculations in metric units, while another used English units.

  • Soyuz 5 Lands Hard

    After participating in the first in-flight transfer of cosmonauts from one spacecraft to another, pilot Boris Volynov (pictured), led Soyuz 5 back toward Earth. When the service module failed to detach, the craft plummeted toward earth upside-down, subjecting Volynov to extreme heat. The craft subsequently crashed hundreds of miles off course in the Ural mountains, breaking several of Volynov's teeth in the impact and leaving him to awaiting rescue in -38 degree (F) temperatures. He walked "a few kilometers" to a village and took shelter until help arrived. (<a href="http://www.wired.com/science/discoveries/news/2009/01/dayintech_0116">Source</a>)

  • Hubble Telescope Can't See

    Although NASA's Hubble Space Telescope has produced incredible images of space for more than 20 years, it was nearly a failure of galactic proportions. After its launch in 1990, Hubble produced only blurry, grainy pictures due to a faulty mirror. Luckily, it was fixed three years later, and went on to capture some of the most incredible space images ever seen.

  • Kwangmyŏngsŏng Program Flounders

    North Korea has attempted to launch its Kwangmyŏngsŏng satellites four times, and met with four failures. North Korean Umha-2 rockets, pictured, were used on the second and third launches but could not bring their satellite payloads into orbit. Fortunately, all the missions were unmanned.

  • H-IIA Rocket Self-Destructs

    H-IIA is the launch system of the Japanese Aerospace Exploration Agency (JAXA). Its sixth launch was supposed to deliver a spy satellite into orbit, but a rocket booster failed to detach properly from the H-IIA, making the rocket too heavy to enter orbit. Ground control sent a destruct command to the rocket shortly after.

  • Glory Sputters Out

    Climate science was dealt a blow in March 2011, when NASA's Glory satellite--which was supposed to study humans' effect on the Earth's atmosphere--failed to launch. The Taurus XL rocket carrying the observation satellite crashed into the Pacific after liftoff when Glory's protective casing didn't open.

  • Cluster Breaks Up

    Cluster, a group of spacecraft launched by the European Space Agency (ESA) in 1995, were lost when launch vehicle Ariane 5 failed to reach orbit. The launch vehicle, on its maiden voyage, self-destructed after a software error caused it to veer off-course. What was the problem? A glitch similar to the issue that doomsayers said would bring disaster at 11:59:59, December 31, 1999. This time, however, the threat was real.

  • Apollo 13 'Fails Successfully'

    NASA's most famous black eye came on April 14, 1970, when an oxygen tank on Apollo 13's service module exploded and the crew narrowly managed to abort the mission safely. The damaged service module that began the drama is pictured here, courtesy of <a href="http://www.alanbeangallery.com/">Alan Bean</a>, Apollo astronaut and "first artist on another world."

  • Naro-1 Sputters

    Naro-1 was a carrier rocket created for South Korea's Korean Aerospace Research Institute. Both attempts to launch Naro-1 ended in failure, with one disintegrating in the atmosphere and another exploding before making it to space.

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