75 questions · 27 almanac · 0 findings

Lunar Science and Exploration

The Moon's geology and the missions that have studied it.

Almanac Missing the Moon, Finding the Solar Wind
  • Why did Luna 1 miss the Moon, and by how much?
  • What did Luna 1's instruments detect that became known as the solar wind?
  • What did Luna 1 reveal about the Moon's magnetic field?
  • What does it mean for an object to become 'heliocentric,' and why was Luna 1 the first human-made object to do so?
Almanac The First Touch of Another World
  • How fast was Luna 2 traveling when it struck the Moon, and how was the impact detected on Earth?
  • What did Luna 2 carry to the lunar surface as a marker of the mission?
  • What measurements did Luna 2 confirm about the solar wind and the Moon's magnetic field before impact?
Almanac The Far Side, Finally Seen
  • Why had no human ever seen the Moon's far side before Luna 3?
  • How did Luna 3 photograph, develop, and transmit images of the lunar far side back to Earth in 1959?
  • What surprised scientists about the appearance of the Moon's far side compared to the near side?
  • Why do scientists think the near side of the Moon has more dark basaltic plains than the far side?
Almanac The Moon Was Not Smooth After All
  • Why did some scientists worry a lunar lander might sink into deep dust before Ranger 7 flew?
  • How many photographs did Ranger 7 transmit in its final minutes before impact, and how did its resolution compare to Earth-based telescopes?
  • What did Ranger 7's images reveal about the Moon's surface that earlier telescope observations could not show?
  • How did Ranger 7's data influence the engineering design of the Apollo landers five years later?
Almanac The Dust Was Only a Rumor
  • Why did some scientists before 1966 believe the lunar surface might be a deep layer of dust that could swallow a spacecraft?
  • How did Luna 9 cushion its landing and stabilise itself on the Moon's surface using petal-like panels?
  • What did Luna 9's photographs reveal about the physical nature of the lunar surface?
  • How did British astronomers at Jodrell Bank manage to decode Luna 9's images before the Soviets released them?
Almanac Ground Firm Enough for Boots
  • What did Surveyor 1 measure about the Moon's soil that Luna 9's photographs alone could not confirm?
  • How many photographs did Surveyor 1 transmit before the lunar night ended its mission, and what did NASA learn from them?
  • Why did engineers compare the Moon's surface bearing strength to wet sand, and why was that reassuring news?
  • How did Surveyor 1's data directly inform the Apollo program's crewed lunar landings three years later?
Almanac A Hatch That Took Ninety Seconds
  • Why did a pure-oxygen cabin atmosphere make the Apollo 1 test so dangerous once a spark occurred?
  • Why couldn't Grissom, White, and Chaffee escape the capsule once the fire started?
  • What organizational failures did the investigation identify beyond the faulty wiring itself?
  • What design changes did NASA make to the Apollo command module after the fire?
Almanac Earth Seen Whole, and Alone
  • Why did NASA send Apollo 8 all the way to the Moon instead of testing the lunar module in Earth orbit as originally planned?
  • What did Frank Borman, James Lovell, and William Anders do during their Christmas Eve broadcast from lunar orbit?
  • How did William Anders come to photograph the Earthrise image, and why did it change how people saw the planet?
Almanac Two and a Half Hours on Another World
  • Why did Armstrong take manual control of the lunar module during descent?
  • What scientific instruments did Apollo 11 leave behind on the Moon?
  • How much lunar material did Apollo 11 bring back to Earth, and what has it revealed?
Almanac Landing Within Sight of an Old Probe
  • How close did Apollo 12 land to the Surveyor 3 probe, and why did that matter?
  • What was the purpose of the Apollo Lunar Surface Experiments Package first deployed on Apollo 12?
  • What did retrieving pieces of Surveyor 3 let scientists study?
Almanac Fifteen Minutes to Rewrite the Mission
  • What caused the oxygen tank inside Apollo 13's service module to rupture on 13 April 1970?
  • Why did the crew retreat into the lunar module Aquarius, and what problem did that create given its original design?
  • How did the Apollo 13 crew improvise a working carbon dioxide scrubber from mismatched parts?
  • What is a free-return trajectory, and how did it help bring Apollo 13's crew home safely?
Almanac Miles and Miles and Miles, He Said
  • Why did Apollo 14 land at Fra Mauro, and what connection did that site have to the aborted Apollo 13 mission?
  • How did Alan Shepard become the oldest person to walk on the Moon after being medically grounded for a decade?
  • What do the Fra Mauro samples suggest about the impact that created the Mare Imbrium basin?
  • How did Alan Shepard's golf shots on the Moon behave differently than they would have on Earth?
Almanac The Last Bootprints of the Century
  • What did Apollo 16's samples from the Descartes Highlands reveal about the origin of the lunar highlands?
  • Why was Harrison Schmitt's presence on Apollo 17 significant, and why had NASA resisted sending scientists before?
  • How much lunar material did Apollo 16 and 17 together bring back to Earth?
  • Why has Eugene Cernan's status as the last person to walk on the Moon lasted so much longer than anyone expected?
Almanac A Handshake Above the Cold War
  • How did the docking adaptor used in Apollo-Soyuz allow incompatible American and Soviet spacecraft to connect?
  • What did the astronauts and cosmonauts actually do during the 44 hours of joint operations in orbit?
  • How did the Apollo-Soyuz docking protocols pave the way for the International Space Station?
Almanac Two Billion Years of Lunar Dark, Broken Open
  • How did the LCROSS mission use a spent rocket stage to detect water ice on the Moon?
  • What percentage of the excavated lunar material turned out to be water, according to the spectroscopic analysis?
  • Why are permanently shadowed craters near the lunar poles considered cold traps for volatile ices?
  • Why does confirming water on the Moon matter for future lunar missions?
Almanac First Footprint on the Moon's Hidden Face
  • Why had no spacecraft ever landed on the Moon's far side before Chang'e 4 in 2019?
  • How did the Queqiao relay satellite solve the communication problem for a lander on the Moon's far side?
  • Where did Chang'e 4 land, and why is the South Pole–Aitken Basin scientifically significant?
  • How does the geology of the Moon's far side differ from the near side that faces Earth?
Almanac First to the Moon's Shadowed Pole
  • Why is the Moon's south pole considered scientifically significant, and what might its permanently shadowed craters contain?
  • How did Chandrayaan-3's landing differ from earlier Moon landings by the Soviet Union, the United States, and China?
  • What happened to Russia's Luna-25 mission just before Chandrayaan-3's landing?
  • What did the Pragyan rover find in the lunar regolith during its two weeks of operation?
Almanac Upright at Last, in the Sea of Crises
  • What went wrong with the Astrobotic Peregrine and Intuitive Machines IM-1 lunar landing attempts before Blue Ghost?
  • Where did Blue Ghost land on the Moon, and how long did it operate before lunar night ended the mission?
  • What did the ten NASA science instruments aboard Blue Ghost measure on the lunar surface?