Saturday, October 11, 2014

My Day at JPL Open House in Pasadena, CA

An appropriate calculator to take to JPL, since the HP 41C was involved in space travel. 

If you get a chance, you are in the Los Angeles area, and the topics of astronomy, geology, and engineering interest you; I recommend that you visit the Jet Propulsion Laboratory in Pasadena, CA.  JPL is having an open house this weekend (October 11 and 12, 2014), from 9:00 AM to 4:00 PM Pacific time.  

Link to directions is here: 

I would like to share some of the fascinating things I learned about in today's trip.  Even though I may not present much mathematics today, I promise mathematics is involved.

  • The atmosphere of the planet Venus is so toxic, even lead melts on Venus.

  • The LDSD, Low-Density Supersonic Decelerator, is currently being developed and in the testing stage.  The aim is for the LSDS to able to transfer large payloads, allowing for developing large parachutes and drag devices to one day transfer large facilities and human beings to the planet Mars.  Testing will continue through 2015.

  • We will need to be 30 miles in the air from Earth to match the air density of Mars.  At the surface, the air density of Mars is about 1% of Earth's air density.

  • Currently, it takes about 9 months for spacecraft to travel from Earth to Mars.  

  • The speed of sound in dry air on a 68°F (20°C) day is about 342.604 m/s, or about 766.383 mph.  The true speed depends on air density and temperature.  According to NASA, a simple formula to approximate the speed of sound in air is:  

McMurdo Crater, Mars (3D Picture)

  • The above picture of a panorama of the McMurdo Crater on the planet Mars (we needed 3D glasses to see it properly) was made possible because a rover named Spirit could not get enough solar energy to move, instead what little energy it could get was spent taking a picture of the surrounding area.  A long winter in 2006 (on Mars) caused this.  

A Model of Dawn

  • Dawn, a space probe launched in 2007, which runs on ion propulsion explores two of the prominent objects in the solar system's asteroid belt:  the asteroid Vesta and dwarf planet Ceres.  The gas used for ion propulsion is xenon (atomic number 54), which occurs in our atmosphere.  The ion propulsion allows Dawn to achieve incredible speed and efficiency.  However, ion propulsion will probably not be present in automobiles because in order for the propulsion to work properly, friction cannot be present.

  • Encleadus (pronounced en-sell-ah-dus), a moon of Saturn, jets of ice water that sprays through the surface.  However, don't expect humans to live there because average temperature is -330°F (yes, it's that cold!).

  • Europa, a moon of Jupiter, is covered has an ice surface that covers a layer of liquid water.  Scientists theorize that there may be extraterrestrial life in the underground ocean.  

  • The spacecraft Cassini has been exploring Saturn for 10 years.  Since then, we discovered 7 moons of Saturn.  Cassini's final destiny, estimated to be in 2017, is to head into Saturn's atmosphere.

A model of the CG comet  (67P/Churymov-Gerasimenko) - Rosetta is scheduled to land on it November 12, 2014

  • The Rosetta satellite will be the first satellite to attempt to land on a comet.  Specifically, the CG comet, formally known as the 67P/Churyumov-Gerasimenko.  Landing is scheduled to be on November 12, 2014, 5:30 to 9:30 AM, Pacific Time. (  ) No word on whether we will be learning a new language.  

NASA has several spacecraft that focuses on our place in the Universe, the planet Earth.  Some are:

  • AirMOSS (Airborne Microwave Observatory of Subcanopy and Subsurface) measures soil moisture of North America over nine different climate areas.  The primary mission of AirMOSS to measure the health of Earth's vegetation and calculate the net ecosystem exchange (how much carbon enters and exit our ecosystem).

  • UAVSAR (Uninhibited Aerial Vehicle System Aperture Radar) measures how earthquakes, volcanoes, and other similar events affect Earth.  UAVSAR has been used in measuring the effects of the June 2010 Gulf of Mexico Oil Spill and the August 24, 2014 Napa Valley earthquake.

Measuring the salt content of the Earth's oceans with Aquarius

  • The primary objective of the NASA Aquarius mission (Aquarius is shown above) is to measure the salinity of Earth's oceans and any changes that occur.  Because salt adds mass to water, fresh water floats on top of salty, ocean water.   Astrologers will probably be disappointed because this satellite will not calculate natal charts of babies born in the future.  

Screenshot of the EYES on the Solar System software

  • There is an online 3D interactive software that allow you to explore the Solar System and travel of NASA's space probes.  You can even see the action happen against the background of constellations.  The software is free, and it is at:   There was a demo of it in the Solar System Exploration exhibit and it looked super impressive.  Right now, there is only a PC version, but Android and iOS versions are in the works.  The software requires that you are connected to the internet.  

There is so much more to explore.  I didn't get to the exhibits where spacecraft and robotic technology are assembled and fabricated.  If you go, go early, as lines can grow very long as the day passes by.

I hope you find this enjoyable. If you get a chance, go; October 12 (Sunday) is the last day of the open house.   

Take care everyone,


This blog is property of Edward Shore.  2014

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