Space History: Chinese Lunar Orbiter, and Mistaken Identity in a Near-Nuclear Crisis

Five years ago today — October 24, 2007 — the People’s Republic of China launched a spacecraft to orbit and study the Moon.

(Chang’e 1 launch. Public domain image from Wikimedia Commons.)

Chang’e 1, “named for a Chinese legend about a young goddess who flies to the Moon,” entered lunar orbit on November 7, 2007. It carried eight different scientific instruments, and its objectives were to

obtain three-dimensional stereo images of the lunar surface, analyze the distribution and abundance of elements on the surface, survey the thickness of lunar soil and to evaluate helium-3 resources and other characteristics, and to explore the environment between the Moon and Earth.

The spacecraft remained in orbit around the Moon until March 2009, according to the Wikipedia entry.

In other space history, 50 years ago today — October 24, 1962, during the Cuban Missile Crisis — the Soviet Union launched Sputnik 22, which was intended to be an interplanetary mission to fly by Mars. The spacecraft and the upper stage of the rocket

either broke up as they were going into Earth orbit or had the upper stage explode in orbit during the burn to put the spacecraft into Mars trajectory. In either case, the spacecraft broke into many pieces, some of which apparently remained in Earth orbit for a few days.

That debris reportedly showed up on the radar at the Ballistic Missile Early Warning System (BMEWS) site in Alaska, and “was momentarily feared to be the start of a Soviet nuclear ICBM attack.”

Those were scary times. This incident points out the simple fact that space launch technology is of a kind with ballistic missile technology, which is why we spent so much time and effort protecting our U.S. designs and methodologies when I served in the Defense Technology Security Administration.

Facebooktwitterpinterestlinkedinmailby feather

One Space Launch, One Space Landing

Fifty years ago today — October 18, 1962 — Ranger 5 was launched from Cape Canaveral on its mission to the Moon.

(Ranger 5. NASA image.)

Ranger 5 launched atop an Atlas Agena rocket, but unfortunately it did not complete its mission. It was intended primarily to “transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to impacting on the Moon, to rough-land a seismometer capsule on the Moon,” and to complete other objectives, but

Due to an unknown malfunction after injection into lunar trajectory from Earth parking orbit, the spacecraft failed to receive power. The batteries ran down after 8 hours, 44 minutes, rendering the spacecraft inoperable. Ranger 5 missed the Moon by 725 km. It is now in a heliocentric orbit.

In more successful space history, on this date 45 years ago, the Soviet Union’s Venera 4 landed on Venus.

Facebooktwitterpinterestlinkedinmailby feather

Japanese Lunar Mission

Five years ago today — September 14, 2007 — the Japanese Space Agency (JAXA) launched the Kaguya lunar orbiter aboard an H-2A rocket from Tanegashima Island.

(The Moon, as seen by Kaguya’s high-gain antenna monitor camera. JAXA image from the National Space Science Data Center.)

Kaguya was originally named SELENE, for SELenological and ENgineering Explorer, but was renamed Kaguya after Kaguya-hime — i.e., Princess Kaguya — who came to Earth from the Moon in the 10th century Japanese folk tale “Taketori Monogatari” (The Tale of the Bamboo Cutter).

Upon reaching lunar orbit on October 3, 2007, Kaguya deployed two smaller satellites, “Okina” and “Ouna,” named for the old couple in the folk tale who find and adopt Kaguya-hine.

The Kaguya mission completed a global survey of the Moon, looking at its composition, topography, gravity, and other conditions. The mission ended on June 10, 2009, with a pre-planned impact on the lunar surface that was timed to allow observers on Earth to see the flash of impact.

Very cool!

Facebooktwitterpinterestlinkedinmailby feather

Surveyor 5: Pathfinder for Apollo 11

Forty-five years ago today — September 8, 1967 — an Atlas Centaur launch vehicle carried the Surveyor 5 lander out of Cape Canaveral on its way to the moon.

(Surveyor and Apollo landing sites. Note the close proximity of Surveyor 5 (S5) and Apollo 11. NOAA image.)

Surveyor 5 landed on the moon on September 11, 1967, but not until mission controllers overcame a hardware problem. After the midcourse correction

the spacecraft began losing helium pressure. It was concluded that the helium pressure valve had not reseated tightly and the helium was leaking into the propellant tanks, causing an overpressure which opened the relief valves, discharging the helium. A new emergency landing plan was adopted. Early vernier engine firings were made while there was still helium to slow the spacecraft, reduce its mass, and leave more free volume in the propellant tanks for the helium. The burn of the main retrorocket was delayed [to] an altitude of 1300 meters at a velocity of 30 m/s rather than the planned 10,700 meters at 120 to 150 m/s.

Surveyor 5 landed in the southwest area of Mare Tranquillitatis — the Sea of Tranquility. Two years later, Neil Armstrong and Buzz Aldrin would land Apollo 11 about 30 km away from Surveyor 5’s landing site.

The Surveyor 5 spacecraft operated on the lunar surface for 4 lunar days — shutting down during each 2-week-long lunar night — and sent its final transmission on December 17, 1967.

Facebooktwitterpinterestlinkedinmailby feather

Farewell, Neil Armstrong

Neil Armstrong, first human to walk on the moon, has taken his final small step, his final giant leap into the great unknown.

Other people with deeper insight will pen better tributes than I. All I can contribute is a measure of how much of an inspiration Armstrong and his astronaut colleagues have been to me: in my decision to join the Air Force and to work specifically in space and missiles, and in my desire to explore space in my imagination and my stories.

Thank you, Neil Armstrong, and Godspeed.


Previous Armstrong-related space history posts:
Apollo 11’s 40th Anniversary
Happy Birthday, Neil Armstrong

Facebooktwitterpinterestlinkedinmailby feather

Last of the Pre-Apollo Lunar Orbiters

Forty-five years ago today — August 1, 1967 — Lunar Orbiter 5 was launched by an Atlas Agena from Cape Canaveral.

(Lunar Orbiter 5. NASA image.)

As noted, Lunar Orbiter 5 was the last of the series, “designed to to take additional Apollo and Surveyor landing site photography and to take broad survey images of unphotographed parts of the Moon’s far side.”

The spacecraft acquired photographic data from August 6 to 18, 1967, and readout occurred until August 27, 1967. A total of 633 high resolution and 211 medium resolution frames at resolution down to 2 meters were acquired, bringing the cumulative photographic coverage by the 5 Lunar Orbiters to 99% of the Moon’s surface.

Mission Control commanded Lunar Orbiter 5 to de-orbit and hit the lunar surface five months after its photography mission was completed.

Facebooktwitterpinterestlinkedinmailby feather

Lunar 'Explorer' Launched

Forty-five years ago today — July 19, 1967 — Explorer 35 launched from Cape Canaveral on a Thor-Delta rocket.

(Explorer 35. NASA image.)

Explorer 35 was designed to study the solar wind — specifically, “the interplanetary plasma, magnetic field, energetic particles, and solar X rays” — in the vicinity of the Moon.

According to this mission page, the Explorer 35 launch was the 50th Thor-Delta mission — quite an accomplishment for the launch vehicle team.

Explorer 35 entered its elliptical lunar orbit on July 21st and began six years of observations. The spacecraft “found that the Moon has no magnetosphere, enabling the charged particles of the solar wind to hit the lunar surface,” and effectively creating a “cavity” in the solar wind. It was finally turned off on June 24, 1973.

Facebooktwitterpinterestlinkedinmailby feather

An Ill-Fated Lunar Surveyor

Forty-five years ago today — July 14, 1967 — an Atlas Centaur launched from Cape Canaveral carrying Surveyor 4.

(Sinus Medii, planned landing site for Surveyor 4, imaged in 1994 by Clementine. NASA image from Wikimedia Commons.)

Surveyor 4 was scheduled to touch down on the lunar surface on July 17th, but …

After a flawless flight to the moon, radio signals from the spacecraft ceased during the terminal-descent phase … approximately 2.5 min before touchdown. Contact with the spacecraft was never reestablished, and the mission was unsuccessful.

The original landing target was 0.4 N, 1.33 W in Sinus Medii (“Central Bay”). Surveyor 4 may have exploded before impact, as this site notes that “communications were abruptly lost 2 seconds prior to retrorocket cutoff.”

So, like its sister ship Surveyor 2, Surveyor 4 did not accomplish its mission. Good thing there were seven spacecraft in the series!

Facebooktwitterpinterestlinkedinmailby feather

Star Wars Day Space History …

… from our little part of this galaxy, not that long ago.

Forty-five years ago today — May 4, 1967 — an Atlas Agena rocket launched from Cape Canaveral carrying the Lunar Orbiter 4 on its mission to the Moon.

Because the previous three Lunar Orbiters had “completed the required needs for Apollo mapping and site selection,” NASA tasked this fourth orbiter to “perform a broad systematic photographic survey of lunar surface features in order to increase the scientific knowledge of their nature, origin, and processes, and to serve as a basis for selecting sites for more detailed scientific study by subsequent orbital and landing missions.”

Lunar Orbiter 4 developed problems with the camera door, however: it did not open and close correctly when commanded, and mission controllers feared that it might stick closed so they commanded it to remain open.

This required extra attitude control manuevers on each orbit to prevent light leakage into the camera which would ruin the film. On 13 May it was discovered that light leakage was damaging some of the film, and the door was tested and partially closed. Some fogging of the lens was then suspected due to condensation resulting from the lower temperatures. Changes in the attitude raised the temperature of the camera and generally eliminated the fogging. Continuing problems with the readout drive mechanism starting and stopping beginning on 20 May resulted in a decision to terminate the photographic portion of the mission on 26 May.

Even with those problems, the spacecraft was able to read and transmit “419 high resolution and 127 medium resolution frames were acquired covering 99% of the Moon’s near side at resolutions from 58 meters to 134 meters.”

And in more recent space history …

Just a decade ago, on this date in 2002, the remote sensing spacecraft Aqua was launched from Vandenberg AFB by a Delta-II rocket.

(A depiction of the “A-Train” formation of satellites in similar orbits. Aqua was the first vehicle in the A-Train. NASA image.)

Originally known as Earth Observation System Afternoon One (EOS-PM1) for the time of day it would cross the equator, the mission was renamed Aqua

for the large amount of information that the mission is collecting about the Earth’s water cycle, including evaporation from the oceans, water vapor in the atmosphere, clouds, precipitation, soil moisture, sea ice, land ice, and snow cover on the land and ice. Additional variables also being measured by Aqua include radiative energy fluxes, aerosols, vegetation cover on the land, phytoplankton and dissolved organic matter in the oceans, and air, land, and water temperatures.

If I recall, one of the folks I worked with at the Defense Technology Security Administration came to us from the Aqua program. Pretty cool.

Facebooktwitterpinterestlinkedinmailby feather

Surveyor-3 — To the Moon and (Partly) Back Again

Forty-five years ago today — April 17, 1967 — an Atlas-Centaur rocket launched from Cape Canaveral, sending Surveyor-3 on its way to the Moon.

(Apollo-12 mission commander Pete Conrad retrieves parts from Surveyor-3. The lunar module “Intrepid” is visible in the distance. NASA image taken by lunar module pilot Alan Bean. A higher-resolution version is available here)

Surveyor-3 landed on the Moon on April 19th, the second of the Surveyor series to make a soft landing. Its other objectives were to transmit television images of the lunar surface, use its sampler to probe the surface materials, and test the surface’s load-bearing strength and other properties in advance of the Apollo missions.

In what I think of as a fulfillment of Surveyor-3’s destiny, two and a half years later — on November 19, 1969 — Apollo-12 landed within about 600 feet (180 meters) of Surveyor-3. As shown in the image above, astronauts Pete Conrad and Alan Bean visited the spacecraft and examined it closely. They retrieved several parts, including the television camera, and returned them to Earth for analysis. Surveyor-3’s camera was put on display in the National Air and Space Museum.

Facebooktwitterpinterestlinkedinmailby feather