MAVEN

October 11, 2014


What would you call a BIG story?  ISIL, Ebola Virus, Benghazi, IRS problems with Tea Party members, the search for the missing Malaysian jet?   All are big stories and certainly deserve necessary airtime and commentary.    There is one story that has gotten almost zero (0) airtime from the media and one story I feel is absolutely remarkable in importance relative to pushing the technological envelope.  The Mars MAVEN mission has been a huge success to date with the unmanned craft now orbiting the “red” planet.

MAVEN is an acronym for NASA’s Mars Atmosphere and Volatile Evolution spacecraft which successfully entered Mars’ orbit at 10:24 p.m. EDT Sunday, Sept. 21, 2014 after traveling 442 million miles. The purpose for the mission is to study the Red Planet’s upper atmosphere as never before.  This is the first spacecraft dedicated to exploring the tenuous upper atmosphere of Mars with the following objectives:

OBJECTIVES:

  1. Determine the role the loss of volatile gaseous substances to space from the Martian atmosphere has played through time.
  2. Determine the current state of the upper atmosphere, ionosphere, and interactions with the solar wind.
  3. Determine the current rates of escape of neutral gases and ions to space and the processes controlling them.
  4. Determine the ratio of stable isotopes in the Martian atmosphere.

There is some thought that by understanding the atmospheric conditions on Mars, we will gain better insights as to the evolutionary processes of that planet and maybe some ability to predict evolutionary processes on Earth.  Also, discussions are well underway relative to future establishment of colonies on Mars.  If that is to ever happen, we definitely will need additional information relative to atmospheric and surface conditions.

SYSTEM:

The graphic below is a pictorial of the MAVEN system.  This is somewhat “busy” but one which captures several significant specifics of the hardware including onboard instrumentation.

T0TAL SYSTEM

Please note the graphic at the bottom comparing what is believed to be early atmospheric conditions with current atmospheric conditions.  The loss of magnetic fields surrounding the planet is contributory to atmospheric losses.  Could this happen to Earth’s atmosphere?  That’s a question that we have yet to answer.  Additional specifics can be seen from the following:

MAVEN SPECIFICS

ENTRY:

After a 442 million mile trip, how did MAVEN hook up with Mars?  Very, very carefully.  The blue line in the graphic below shows the first part of MAVEN’s trajectory during its initial approach and the beginning of the 35-hour capture orbit. The red section of the line indicates the 33-minute engine burn that slows the spacecraft so it can be captured into Martian orbit. Mars’ orbit around the sun is indicated by the white line to the right of the planet, and the Martian moons’ orbits are dimly visible in the background.  This is a remarkable example of engineering and physics allowing for pinpoint accuracy relative to entry and the establishment of orbital stability.

ENTERING THE PLANET

INSTRUMENTATION:

MAVEN carries three instrument suites with eight scientific instrument packages designed to study the upper atmosphere and ionosphere of Mars and its interactions with the solar wind.  Three of the instruments are located on the Articulating Payload Platform extending from the bus, including the Imaging Ultraviolet Spectrograph and a mass spectrometer that will sample the atmosphere in situ.  The hardware housing these three packages is shown as follows:

INSTRUMENT PACKAGE

The The Particles and Fields Package, built by the University of California at Berkeley with support from CU/LASP and Goddard Space Flight Center, contains six instruments that will characterize the solar wind and the ionosphere of the planet. The Remote Sensing Package, built by CU/LASP, will determine global characteristics of the upper atmosphere and ionosphere. The Neutral Gas and Ion Mass Spectrometer, provided by Goddard Space Flight Center, will measure the composition and isotopes of neutral ions. MAVEN also carries a government-furnished Electra UHF radio, shown by the graphic below, provides back-up data relay capability for the rovers on Mars’ surface.

Communication Module

Lockheed Martin, based in Littleton, Colorado, built the MAVEN spacecraft and provides mission operations. NASA’s Jet Propulsion Laboratory is providing navigation services, and CU/LASP conducts science operations and data distribution.

HISTORY:

On February 19, the MAVEN team successfully completed the initial post-launch power-on and checkout of the spacecraft’s Electra ultra-high frequency (UHF) transceiver. This receiver is shown with the graphic below.  This relay radio transmitter and receiver will be used for UHF communication with robots on the surface of Mars. Using the orbiter to relay data with this relay radio from Mars rovers and stationary landers boosts the amount of information that can be relayed back to Earth.

A part of NASA’s Mars Scout program, MAVEN is the culmination of 10 years of R&D. Some of that R&D went into designing the materials for the spacecraft’s instruments as well as for the satellite itself, which weighs about as much as a small car and has a 37 ft wingspan, including solar panel arrays.  That panel system is shown as follows:

SOLAR ARAY

As you can see from the JPEG, the array is huge but necessary to power the complete system.

The craft’s core structures are made with carbon fiber composites made by TenCate Advanced Composites. The company is experienced in the design and fabrication of composites for aerospace applications, having already supplied them to previous Mars missions, including the Rover and Curiosity rovers. For MAVEN, which will orbit Mars for about one Earth year, TenCate engineered composite face sheets sandwiched between aluminum honeycomb sheets for the spacecraft’s primary bus structure.

Other materials in the orbiter include a cylindrical aluminum boat tail on the aft deck that provides engine structural support. The craft is kept at the correct operating temperature — 5F to 104F — using active thermal control and passive measures, such as several thermal materials for conducting or isolating heat. Most of the orbiter is enclosed within multi-layer insulation materials; the outside layer is black Kapton film coated with germanium.

SUMMARY:

Hopefully, you can see now why I feel MAVEN is a BIG story worthy of considerable air time.  It’s a modern-day engineering marvel.  I welcome your comments:  bobjengr@comcast.net.

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