UMSF space history photo of the month Options

[Guest_PhilCo126_*]

Maybe we could make this a monthly item, in which we could look back at the history of Unmanned Space missions.
For January 2008 I've chosen an image showing the coverage of the Sun by early Pioneer 5-8 spacecraft.
Pioneer 5 to 8, or Pioneer V to VIII using the system of Roman numerals in vogue during the early 1960s for spacecraft designations, were directed towards the Sun along the earth's orbit to monitor solar activity. Pioneer V was launched on 11th March 1960 and provided the very first space weather report 4 to 8 hours before a solar storm hit the Earth.
Some of this Pioneer quartet, Pioneer 6-7-8 even provided updates on our Sun's activity during the early Apollo Moon landings in order to check the damaging potential of solar flares to affect the astronauts.

[Guest_PhilCo126_*]

Doug, the 58 cm diameter spheroidal probe Luna 9 "landed" on the Moon in February 1966 and this capsule weighted 100 kg.
It sat ontop the 1440 kg main bus and was ejected up & sideways by springs, the main bus impacted onto the lunar surface... is there somewhere an official definiton of "soft" landing?
Next month's photo = Mariner 4

[dvandorn]

Doug, the 58 cm diameter spheroidal probe Luna 9 "landed" on the Moon in February 1966 and this capsule weighted 100 kg.
It sat ontop the 1440 kg main bus and was ejected up & sideways by springs, the main bus impacted onto the lunar surface... is there somewhere an official definiton of "soft" landing?
Next month's photo = Mariner 4

Well -- Pathfinder was dropped onto Mars from about 100 meters and bounced up half a km on its first bounce, and they called that a soft landing...

There was an attempt to define such things as the Mars airbag systems, the early Luna landers (which also used airbags) and the attempted-but-never-successful balsawood-packed Ranger surface instrument packages as "hard survivable landers," but the concept never took solid hold. Any system that delivers a reasonably complex instrument package to the surface of a planet seems to be considered a soft landing system, these days. (I would argue that penetrators are in a special class of their own, neither soft landers nor padded/bagged/protected survivable landers.)

-the other Doug

[djellison]

Well -- Pathfinder was dropped onto Mars from about 100 meters and bounced up half a km on its first bounce, and they called that a soft landing...

The bridle was cut 21.5 m above the ground and impacted at a velocity of 16 m/s (14 m/s vertical and 12 m/s horizontal). It bounced about 12 m.

(paraphrased from http://burro.astr.cwru.edu/stu/advanced/20...pathfinder.html )

Doug