Showing posts with label Atlas-Centaur. Show all posts
Showing posts with label Atlas-Centaur. Show all posts

Sunday, May 7, 2017

50 Years Ago: Surveyor 3 on the Moon

Photo of Surveyor 3 actually on the Moon, as taken by astronauts of Apollo 12 years later.

Fifty years ago, NASA continued its preparations for the Apollo program by landing another probe on the lunar surface. This was the third in the Surveyor series, built by Hughes Aircraft, and principally tasked with getting photos of the surface, and sampling the soil. This was the first space probe to include an extendable scoop to bring lunar dust to a sampling experiment on the lander. Surveyor 3 lifted off from Cape Kennedy from launch complex LC-36B on April 17. 

An Atlas-Centaur booster used to place the Surveyor spacecraft on the Moon. This is the one from Surveyor-1. 

Surveyor 3 touched down on April 20, 1967, in the Mare Cognitum part of Oceanus Procellarum. It had a hard landing because the descent radar incorrectly calculated the altitude and shut the engine down early. It then bounced several times, as high as 10-meters on one bounce, eventually soft-landing and staying upright. Over the short time of its mission it took over 6,000 images to send to excited scientists on Earth.


One of the panorama-series of images taken by Surveyor 3.
 
The sampling arm on the spaceprobe made four short trenches in the soil. Each scoop would bring the sample up to a camera that would then take close pictures of the soil appearance and then transmit the images back to Earth.
Surveyor 3 is the most famous of the seven Surveyor missions, because of what happened during the Apollo 12 mission in 1969. Astronauts from Apollo 12 landed very close to the spacecraft (on purpose!) and retrieved several pieces for return to Earth and analysis. 
 

The camera from Surveyor 3, currently on display at the Smithsonian National Air and Space Center in Washington, D.C.

Thursday, June 2, 2016

50 Years Ago: Surveyor 1 Lands Safely on Moon

Lunar view from Surveyor 1 from the Oceanus Procellarum. NASA.
 
NASA finally did it, fifty years ago. On June 2, 1966, the Surveyor 1 lunar probe fired its retrorockets and descended down to the lunar surface after a 63.5 hour flight time from Earth. For this mission, science instruments were left off and focus was given to the important photographic and television equipment. 
Liftoff on May 30, 1966.
 
The flight began on May 30th from the LC-36A platform at Cape Canaveral, Florida. Propulsion was of course the venerable Atlas rocket with a Centaur second stage to take Surveyor to the Moon. This was a straight flight, there was no plan to orbit first and then land. The retrorockets slowed the vehicle down to a low altitude of about 11 feet above the surface and it dropped down onto the lunar soil. It was a little over 4 months since the Soviets had safely landed Luna 9, and this was the first success for NASA to land anywhere off the Earth.
Transmitted image of one of Surveyor's landing pads in the lunar soil.
 
Television transmitted images continued through July 14. Over 11,000 pictures were taken and sent back to Earth. Although no science experiments were aboard, engineering sensors relayed information about the condition of the probe and condition of the lunar surface.
In 2009, NASA's Lunar Orbiter space probe managed to locate and photograph the Surveyor 1 spacecraft still sitting on the surface of the Moon. The shadow can easily be picked out.
 

Tuesday, March 17, 2015

50 Years Ago: Asset Lost at Sea and an Atlas Rocket Explodes

Back on February 23, 1965 the United States Air Force lost one of its Assets. Literally. As part of Project Asset, the US Air Force was testing the heat shield part of the cancelled DynaSoar X-20 program. Realizing that the data on glider re-entry would still be valuable, the ASSET program continued and the information would later be used to help design the Space Shuttle.

The Asset launches used pad 17B on Cape Canaveral, and were planned to arc out over the Atlantic and have the glider test craft recovered for analysis. ASV-1, launched on a Thor rocket, succeeded in re-entry and landing in the ocean, but it's recovery system malfunctioned and it sank and was lost. Remaining missions used a Thor-Delta rocket configuration using a second stage to propel the craft on a steeper re-entry path. The second launch was also a disaster, the second stage malfunctioned and the craft was self-destructed in flight. ASSET 3 was a success, and the craft recovered and is preserved in the US Air Force Museum in Dayton, OH. The other flights were also lost at sea after successful flights but failures in recovery. ASV-6, occurring 50 years ago, was the end of the program.

Pictures by Ed Hengeveld.

Within a few weeks of the ASV-6 failure, there was another disaster at the Cape. Two seconds after ignition on Pad 36B, an Atlas-Centaur rocket carrying a dummy test Surveyor spacecraft, exploded into a fireball. A fuel valve shut off at ignition, causing 2 of 3 engines to fail. The rocket collapsed back onto the launchpad, having only risen three feet. It then tipped over and exploded onto the ground. No one was hurt and the damage was estimate at $5 million.

Atlas-Centaur 5 on Pad 36B.

Flames surround the rocket as it settles back onto the pad.

The explosion engulfs the tower as well.

More distant view of the explosion.

Wreckage at the site.