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Mesospheric Aerosol Sampling Spectrometer MASS

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					                    Mesospheric Aerosol Sampling
                       Spectrometer (MASS)

                            Z. Sternovsky, S. Knappmiller
                               S. Robertson, M. Horanyi
                       Laboratory for Atmospheric and Space Physics,
                              University of Colorado, Boulder
                        Physics Department, University of Colorado,
                                        Boulder



11th PDP Workshop                                                Jun 28 - July 1 2006
                                                         2

                              Outline




   •    NLC, PMC, PMSE
   •    Dusty plasma issues
   •    The MASS payload
   •    Launch




UCCS presentation                       March 17, 2006
                                                                                            3

                                                          NLC, PMC

Noctilucent clouds                              Polar mesospheric clouds




                    - Ice particles nucleating to ~ 50 nm in size
                    - 82 km altitude, typically ~ 5 km vertical extent
                    - temperatures < 150 K
                    - seasonal variation: Jun – Aug
                    - polar phenomenon ( approx. > 50 deg)
UCCS presentation                                                          March 17, 2006
                                                         4
                    Microphysical model of
                     NLC/PMC formation




                                    85 km




UCCS presentation                       March 17, 2006
                                                                         5
                          Polar Mesospheric
                        Summer Echoes (PMSE)


                    - Charged aerosol particles
                    - Aerosol particles coupled to neutral
                    turbulence
                    - Bragg scattering (electron density
                    gradients)




                                 Models by
                                 Lie-Svendsen et al., JRG, 2003
                                 Scales and Ganguli, NJP, 2004

UCCS presentation                                       March 17, 2006
                                                                                         6
                                            The charged aerosols
                                           layer is a dusty plasma




                                                         Altitude
     – Charging of the aerosol particles
         (T ~ 150 K, na ~ ne ~ 1O3 – 104 cm-3, UV)
     – Electron diffusivity
     – Global E-field
                                                                           85 km
     – Irregularities in E-field
     – Neutral turbulence is important




                                                     Electron bite-out
                                                     DROPPS, Pfaff et al, GRL, 2001
UCCS presentation                                                       March 17, 2006
                                                                                       7
                                                 In-situ measurements
                                                  - Particle detectors -


      a) Faraday cup             b) Mag. shielded             c) MASS
                                 patch collectors
          Air flow

                        Biased
                        grids




       Electrometer


         O. Havnes                B. Smiley
         L.J. Gelinas             S. Robertson
         C.L. Croskey
         M. Rapp



UCCS presentation                                                     March 17, 2006
                                                                                            8
                                        Magnetically shielded dust
                                                detectors
                     light particle

           aerosol




                                      Data returned from the unbiased an biased probe
                                      on upleg during MIDAS MaCWAVE campaign in
                                      July, 2002. Note the negative aerosol layer at
                                      82.5km and the broad positive aerosol layer from
                                      82-84 km.
UCCS presentation                                                          March 17, 2006
                                                              9

                                      MASS

           Airflow with charged
           aerosol particles




          Biased
          collectors
                                  E




             Unbiased
             collectors

UCCS presentation                            March 17, 2006
                                                        10

                        MASS performance

       v = 1000 m/s
       82 km altitude




UCCS presentation                      March 17, 2006
                                                                                                                                             11

                                                                                  MASS performance
                                                                                  100




                                                      Collection Efficiency [%]
                                                                                   80

                                                                                                  L2
                                                                                   60             L3
                                                                                                  L4
                                                                                                  R4
                                                                                   40


                                                                                   20


                                                                                    0
                                                                                        10        100      1000   10000   100000

                                                                                                         Mass [amu]

                                                                                                   Aerosol Radius [nm]
                                                                                                                      1

                                                                                  100




                                           Collection Efficiency [%]
                                                                                  80


                                                                                  60         Electrode
                                                                                                   1
                                                                                  40
                                                                                                   2
                                                                                                   3
                                                                                  20
Ion beams of variable energy are used to
calibrate the MASS instrument                                                      0
                                                                                    10           100       1000   10000    100000

                                                                                                         Mass [amu]
  UCCS presentation                                                                                                         March 17, 2006
                                                                                                       12

                                                       The MASS payload




                                                                                            ms
                                                                           r
                                                                        ete




                                                                                        boo
                                                 n
                                            tatio




                                                                    tom




                                                                                    eld
                         SS



                                        y ro




                                                                 Pho
                       MA




                                                                               E-fi
                                     ada
                                  Far

                                                Dust detectors



       - In-situ detection of charged aerosol particles
       - Global electric field, small scale variation
       - Electron density
       - Optical detection of scattered light

UCCS presentation                                                                     March 17, 2006
                                                                                              13

                                         E-field booms



                                    E-field boom measurements by
                                    the DROPPS payload (1999)




                                                                    Electron bite-out
                                                5V


                                                                                  V10



                    Potential [V]                                                  V12

                                                                                   V1

                                    89     90   91    92       93        94       95     96
                                                     Flight time [s]



UCCS presentation                                                          March 17, 2006
                                                                                             14
                                                Potential distribution
                                                around the payload



                     Ions

                    Aerosol particles




                                    The simulation of the potential distribution around
                                    the DROPPS payload. Sternovsky et al, GRL, 2004
UCCS presentation                                                           March 17, 2006
                                                             15

                                   Launch



   •    July 2007, Andoya, Norway (69˚)
   •    14” payload with Improved Orion engine
   •    v = 1000 m/s at 82 km altitude
   •    Active attitude control
   •    Ground support: radar, lidar
   •    Coordinated with the AIM satellite and
        European rocket campaign


UCCS presentation                           March 17, 2006
                                                                                         16
                                                        AIM
                                          Aeronomy of Ice in the Mesosphere




                                                   CDE: Cosmic Dust Experiment




                          SOFIE: Solar Occultation for Ice Experiment

CIPS: Cloud Imaging and Particle Size Instrument

UCCS presentation                                                       March 17, 2006
                                                                      17

                                      Conclusions



   • Sounding rocket payload in preparation for in-situ
     measurement of mesospheric charged aerosol particles
   • Size distribution measured by the MASS instrument
   • Instrument package for NLC/PMSE study
   • Launch in the summer of 2007 (2 identical payloads)
   • International collaboration




              Research funded by:

UCCS presentation                                    March 17, 2006