Help Shape the Future of Space Exploration

Join The Planetary Society Now  arrow.png

Join our eNewsletter for updates & action alerts

    Please leave this field empty
Blogs
Facebook Twitter Email RSS AddThis

See other posts from January 2014

Bill Dunford profile thumbnail

The Last Flight of the Original Space Ranger

Posted By Bill Dunford

2014/01/06 07:13 CST

Topics: NASA lunar missions before 2005, history, podcasts and videos, the Moon, animation

The first time many people saw the Moon up close was during a remarkable television event: millions watched live as an American spacecraft, the last of its kind, fell toward certain destruction on the lunar surface. 

It was 1965, and the spacecraft was Ranger 9, the final mission in a trail-blazing series of robotic scouting expeditions that made human moon flights possible.

Ranger

Bill Dunford

Ranger
In one corner of the giant Saturn V rocket exhibit at the Kennedy Space Center hangs an example of the machine that paved the way: a robotic Ranger spacecraft.

The "certain destruction" part was intentional. The goal of the final Rangers was simply to fly at the Moon, taking as many still pictures as possible with their onboard television cameras before they crashed at several kilometers per second (thousands of miles per hour).

It was a very long road to get even that far. The first six Ranger flights failed before they accomplished their mission, drifting off into space or failing to send word home. Rocket science was still a new business, and NASA was learning the intricacies of interplanetary flight.

With the Cold War rivalry on the line, the Ranger 7 mission finally succeeded in capturing close-up shots of the lunar landscape near Mare Nubium (the "sea of clouds") in 1964. In celebration, the spot was renamed Mare Cognitum, the "known sea." Ranger 8 performed reconnaissance at Mare Tranquillitatis, which came in handy before the decade was out. Both missions returned images with a detail never before seen by human beings. Among other things, pictures from the suicide flights appeared to confirm that the lunar surface was solid enough to support the coming landings.

The last Ranger performed its swan song live. After a 64-hour flight, Ranger 9 arrived at the moon on March 24, 1965 (which incidentally was about a day after the launch of the Gemini III astronauts).

Images from the probe's six onboard cameras were relayed in real time to a television audience. The BBC reported at the time that "viewers were taken on a dizzying journey as Ranger 9 crashed headlong into the pock-marked crater Alphonsus, near the centre of the Moon's face."

Following is a series of images taken during the last 15 minutes of the descent by the spacecraft's camera "B". Three large craters are initially visible: Albategnius, 96 km (60 miles) wide, Ptolemaeus, 137 km (85 miles) wide, and Alphonsus, 80 km (50 miles) across, where the probe finally impacts. The final frame here was taken at an altitude of about 13 km.

Ranger 9 Final Approach

NASA / JPL / Bill Dunford

Ranger 9 Final Approach
The Ranger 9 lunar probe takes a series of still television images of Alphonsus Crater as the robotic spacecraft plummets toward the surface.

And these are fun. Turn out the classroom lights, crank up the film projector and enjoy this 60s-vintage review of the Ranger 7 flight and a highlight reel of planetary science in 1965. For additional technical details about the flight, here's the original JPL report on Ranger 9.

Ranger 7 Impact Film

NASA / JPL

Ranger 7 Impact Film
A vintage film from NASA narrates the Ranger 7 lunar flight in 1964.
 

Read more blog entries about: NASA lunar missions before 2005, history, podcasts and videos, the Moon, animation

Comments:

Sage Geo: 01/06/2014 07:58 CST

Thanks Bill, Has LRO identified a likely impact crater?

Bill Dunford: 01/07/2014 11:56 CST

I've seen some images captioned as the Ranger 9 impact, but I can't verify them. Here's one I would trust, the Ranger 7 crater: http://lroc.sese.asu.edu/news/index.php?/archives/819-Making-an-Impact-on-History.html

Marshall Eubanks: 01/07/2014 12:39 CST

Ranger 4 is among the fascinating things on the Moon - the spacecraft and rough lander may have worked, but it hit the far side, so no data was returned. I have to wonder if there is a balsawood impactor and seismometer sitting on the far side, waiting for someone to find them.

Bill Dunford: 01/07/2014 01:29 CST

I love that thought. Speaking of the balsawood impactor: http://blogs.jpl.nasa.gov/2013/11/slice-of-history-ranger-impact-limiter/

Elizabeth Koprucki: 01/08/2014 09:53 CST

I enjoyed this blog entry and the videos. My grandma (mom's dad) worked for RCA Astro-Electronics, which worked on the Ranger missions (at least VI onwards.) I don't know if he personally worked on any of the rangers, but I do know he worked on TIROS satellites, which were highlighted in the second video. As a maker and visual communications geek, I loved the models used for the Lunar Orbiter segment at the end of the video.

Elizabeth Koprucki: 01/08/2014 09:54 CST

Oops, that should have been my *grandpa* that worked for RCA.

Bill Dunford: 01/09/2014 09:10 CST

Thanks for sharing that.

Charles Grammer: 01/09/2014 10:18 CST

My father worked for Kodak on the Lunar Orbiters, among other projects, and in his files I found 8-1/2 x 11 glossy prints of the last ten images transmitted by Ranger 7, with descriptions. The last one was taken at an elevation of 1000 feet, and shows an area 100 feet by 60 feet that matches an area with about 9 craters in it to the lower right of the impact crater in the image linked by Bill Dunford. Thanks for the opportunity to match it up!

Bill Dunford: 01/12/2014 07:16 CST

Excellent find.

Bob Ware: 01/13/2014 09:00 CST

Love the story... memories.... Thanks!!!

Leave a Comment:

You must be logged in to submit a comment. Log in now.

Fly to an Asteroid!

Travel to Bennu on the OSIRIS-REx spacecraft!

Send your name

Join the New Millennium Committee

Let’s invent the future together!

Become a Member

Connect With Us

Facebook! Twitter! Google+ and more…
Continue the conversation with our online community!