leonov cover
The Mar. 26, 1965, cover of TIME Cover Credit: ASSOCIATED PRESS

Why the First-Ever Spacewalk Was Kept Secret

Mar 18, 2015

When the first man walked in space, almost nobody knew that it was happening.

Cautious about counting their cosmonaut before he was through the hatch, Soviet space officials kept the plan quiet until after success had been achieved. Aleksei Leonov had already safely returned to the Voskhod II spacecraft — 50 years ago today, on March 18, 1965 — before the Soviet space agency announced that he had left the ship and released photos and video of what had happened. (These days, the English spelling of the cosmonaut's first name is more frequently "Alexei"; in 1965, however, this magazine spelled it with a "ks.") The shots showed Leonov emerging from the craft's hatch before turning a few somersaults to begin his 20 minutes in the nothingness.

The news wasn't a complete surprise for the rest of the world, however. As TIME explained, U.S. radars had been following the Voskhod II and noticed, via a change in reflectivity, that a hole had opened in the craft. They also knew that Soviet ships were big enough and sturdy enough to accommodate several cosmonauts and the necessary equipment and airlock for a spacewalk. (American spaceships of the time had to be lighter, as the U.S. had not developed booster technology to lift spacecraft as heavy as the Soviets'.) The exact technology used by Leonov remained a mystery for the time being — for example, was the cord that tethered him to the ship a mere leash, or an "umbilical" connection for air or communications?

Still, even the USSR's Cold-War enemies couldn't help but admire the feat. As TIME reported, the following week, it was a momentous occasion for all humankind:

Tied to a capsule by a 16-ft. tether, the first human satellite whirled through the vacuum of space at 18,000 m.p.h.

For ten minutes Soviet Cosmonaut Aleksei Arkhipovich Leonov drifted and spun through dreamlike gyrations while he followed the spaceship Voskhod II in its swift, elliptical path around the distant earth. Then, as easily and efficiently as he had emerged from his ship, Leonov climbed back inside. After 15 more orbits, he and his comrade, Colonel Pavel Ivanovich Belyayev, began the long flight home.

With that brief solo excursion into hostile emptiness last week, Lieut. Colonel Leonov took man's first tentative step down the long and dangerous track that he must travel before he truly conquers space . Circling the earth in a sealed and well-provisioned capsule has been demonstrated to be well within human capabilities, but the moon will never be explored, to say nothing of Mars and the other planets, unless fragile men learn to function in the outside vacuum where no earthborn organisms are naturally equipped to live.

Leonov's short "stroll" into personal orbit was one of the most remarkable achievements of the remarkable age of space .

Read the full story, here in the TIME Vault: Adventure into Emptiness

See the Most Beautiful Space Photos of 2014

NASA's Nuclear Spectroscopic Telescope Array's first picture of the sun taken in high-energy X-rays released on Dec. 22, 2014.
NASA's Nuclear Spectroscopic Telescope Array's first picture of the sun taken in high-energy X-rays released on Dec. 22, 2014.JPL-Caltech/GSFC/NASA
NASA's Nuclear Spectroscopic Telescope Array's first picture of the sun taken in high-energy X-rays released on Dec. 22, 2014.
An infrared image of a small portion of the Monkey Head Nebula (also known as NGC 2174 and Sharpless Sh2-252) captured by the Hubble telescope, released on March 17, 2014. The nebula is a star-forming region that hosts dusky dust clouds silhouetted against glowing gas.NASA/ESA/Hubble Heritage Team (STScI/AURA)
A spiral galaxy, also known as M106, about 23 million light years from Earth.
https://www.flickr.com/photos/nasamarshall/15050207206/Eta Carinae: Our Neighboring Superstars (NASA, Chandra, 08/26/14)Eta Carinae is one of the most luminous known star systems in our galaxy. It radiates energy at a rate that is 5 million times that of the Sun. Most of this energy is radiated at infrared wavelengths. It is shrouded in a rapidly expanding cloud of dust which absorbs radiation from the central star and re-radiates it in the infrared.
A reprocessed picture shows off the amazing colors of Europa, a mysterious ice-covered moon of Jupiter, as they have never been seen before released on Nov. 21, 2014.
Reid Wiseman ‏@astro_reid Jun 1A simple toy from my childhood makes for a cool picture in space. pic.twitter.com/yddfNTwiow
Infrared Image of Saturn's Rings
ESA's Optical Ground Station in Tenerife
An aurora near Australia seen from the International SPace Station, released on July 15, 2014.
NASA: LL Ori and the Orion Nebula
The Eagle Nebula, also known as as Messier 16 or M16, and the 'Pillars of Creation' in the constellation Serpens in May 2014.
Russell Crater dunes on Mars released on Feb. 5, 2014.
NASA image of Saturn taken with the Cassini spacecraft wide-angle camera
This vista of the Endeavour Crater rim taken by Opportunity Rover combines several exposures taken by the rover's panoramic camera (Pancam) on the 3,637th Martian day, or sol, of the mission on April 18, 2014 and was released on May 19, 2014.
Alexander Gerst ‏@Astro_Alex Jul 6 View translationHarsh land. Windswept valleys in northern #Africa / Hartes Land. Windgefraeste Taeler in Nordafrika pic.twitter.com/sFcbhRIF2Z
The moon over northeast Greenland in March 2014.
NASA picture of a crescent moon rising over the cusp of the Earth's atmosphere
An optical image, from the Digitized Sky Survey of the Flame Nebula released on May 7, 2014.
New Hubble infrared view of the Tarantula Nebula
The sun emitted a significant solar flare, peaking at 7:28 p.m. EST on Dec. 19, 2014. NASA’s Solar Dynamics Observatory, which watches the sun constantly, captured an image of the event. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel. This flare is classified as an X1.8-class flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.
Astronaut Reid Wiseman tweeted on July 3, 2014 "Hurricane #Arthur has grown an eye since we last met."
The Elephant's Trunk Nebula, also known as IC 1396, on April 14, 2014.
As an island in the moist, atmospherically turbulent North Atlantic, Iceland is often shrouded in cloud cover and hard to observe from space. And lately, the island is making some of its own cloud cover, as the Earth has split open between the Bardarbunga and Askja volcanoes and spewed lava and hot gas. The view of the Holuhraun lava field has been spectacular from the ground and from low-flying aircraft. Infrared imaging makes the view spectacular from space, too.On September 6, 2014, the Operational Land Imager (OLI) on Landsat 8 captured this view of the ongoing eruption. The false-color images combine shortwave infrared, near infrared, and green light (OLI bands 6-5-3). Ice and the plume of steam and sulfur dioxide appear cyan and bright blue, while liquid water is navy blue. Bare or rocky ground around the Holuhraun lava field appears in shades of green or brown in this band combination. Fresh lava is bright orange and red. (Download this large image to see the same area in natural color.)“Thermal imagery can be used to determine the extent of the lava flows and the heat loss,” noted Ashley Davies, a Jet Propulsion Laboratory scientist and leader of NASA’s Volcano Sensor Web team. Infrared imagery can help scientists estimate the effusion rate—the rate at which lava is pouring out of the Earth—as well as the sulfur dioxide content of the plume. “And high resolution imagery of this kind allows us to model the dynamics of the emplacement process. In this case, individual vents can be seen feeding separate lava flows that combine into a main channel feeding an expanding lava flow field.”By some accounts, Holuhraun has spewed more lava this month than any Icelandic volcano since the 19th century. As of September 9, 2014, the new lava flow was 16 kilometers (10 miles) long and covered about 20 square kilometers (8 square miles), according to the University of Iceland.The plume from Holuhraun is rich with sulfur dioxide (SO2), a rotten-smelling gas
APTOPIX Kazakhstan Russia Space Station
Using the CIVA camera on Rosetta’s Philae lander the spacecraft snapped a ‘selfie’ with a comet passing by in the background in this photo released on Oct. 14, 2014.
Saturn, which appears as a thin crescent, broken only by the shadows of its rings, was captured by the Cassini spacecraft cameras in this image released on March 17, 2014. This view looks toward the unilluminated side of the rings from about 42 degrees below the ringplane.
Handout of the evolving universe is shown in this composite of separate exposures taken in 2003 to 2012 with Hubble's Advanced Camera for Surveys and Wide Field Camera 3
Reid Wiseman ‏@astro_reid Jul 1Here is a #TodaySunrise from space for @MLauer pic.twitter.com/xyckQ0AAdVHere is a #TodaySunrise from space for @MLauer." - Reid Wiseman via Twitter on July 1, 2014.
NASA's Nuclear Spectroscopic Telescope Array's first picture of the sun taken in high-energy X-rays released on Dec. 22,

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