Europlanet : 5th IPPW - New instruments

by Doug Ellison in Potsdam

This afternoon was a smörgåsbord of new mission ideas from around the world including JPL, Russia and France - I'll split it between stories to make it easier to swallow!

JPL's Kevin Baines reported on the highlights of the 5th International Planetary Probe Workshop that took place a few weeks ago in France. The workshop brings together some of the scientists and engineers involved in designing the vehicles and the instruments we need to go and explore the solar system.

Kevin talked about flying a balloon to Titan, and a metal balloon to Venus. So dense is the Venusian atmosphere that to fly around at about 10km attitude, you don't need a big balloon like you do on Earth - just a set of metallic bellows that can be inflated. But down at 10km you have the serious issues of high temperature, high pressure, and the potential for super-critical carbon dioxide gas chemically eroding your vehicle.

He then talked about two new instrument designs that might be used to identify noble gasses in atmospheres. The bad news is that noble gases ( such as neon and xenon ) are chemically and spectroscopically inert - so they're impossible to identify remotely - you have to measure them in situ. The good news is that they preserve a record of the past in terms of planetary evolution. What was delivered to planets via comets, what's been blown off with solar wind, and what are the ratios of the various neon isotopes which might tell us just how closely related Venus and Earth were at the formation of the solar system and help us understand how they ended up so different today.

A team led by Brian Drouin at JPL are working on an instrument called SUGARS (bad acronym time folks...) - SUbmillimeter in situ Gas Analysis using Rotational Spectrometry. An instrument of about 4 to 6 kilograms, using only 15-25 watts of power which will measure gases, including the noble gases, down to - currently parts per 5 billion - and with predictions of being able to identify them down to a few orders of magnitude more than that (parts per trillion or more).

Dave Young and others at the Southwest Research Institute are working on MBTOF - Multi Bounce Time of Flight Mass Spectrometer. The charged ions get bounced back and forth between electrostatic mirrors before finally being detected - and as an instrument it will be at least 30,000 times more sensitive than a current time of flight mass spectrometer on Rosetta. Sending this instrument to Venus might be a challenge. I didn't know this - but because of the requirement for direct to Earth communications during entry in to the atmosphere of Venus - the orbital mechanics dictate that entry into Venus be a harsh 400G profile instead of the usual 10-20G you might expect with a planetary entry. A comment from the floor suggested that with a relay spacecraft you could do away with that orientation issue. Next up - hot air and boiling water....