Conference 7.286::space

515.0. "Artificial Cloud Experiments" by MTWAIN::KLAES (N = R*fgfpneflfifaL) Tue Mar 14 1989 15:02

Charles Redmond
Headquarters, Washington, D.C.                     March 10, 1989
 
Joyce B. Milliner
Wallops Flight Facility, Wallops Island, Va.
 
    RELEASE:  89-30
 
    ARTIFICIAL CLOUDS TO BE VISIBLE IN CANADA AND U.S.
  
     Four suborbital rockets, two Black Brant Xs and two Nike-Orions,
are scheduled to be launched from Canada during the next few weeks as
part of a major NASA sounding rocket campaign. 
 
     Two of the rocketborne scientific experiments, programmed to
create artificial clouds at high altitudes over Canada, are scheduled
for launch during late March from Canada's Churchill Research Range on
Hudson Bay.  These colorful barium releases will be visible, cloud
cover permitting, to residents in Central and Eastern Canada and in
North-central United States, according to the experimenters. 
 
     The other two rockets, carrying upper atmosphere experiments
which will not be visible to residents, are scheduled to be launched
between March 16 and March 24. 
 
     The objective of the barium release payloads is to measure
electric fields aligned with Earth's magnetic field.  Such fields
are thought to be responsible for accelerating electrons to create
aurora but their locations and strengths have not been well
established by measurements.  Using the barium ions as optical
tracers, the electric fields are measured by observing how the motion
of the barium ions deviates from the predictable motion that comes
from the initial injection velocity and gravitational and "magnetic
mirror" forces. 
 
     The launch window period is March 25 through April 11 with launch
opportunities each day in the late evening and early morning.  If
required, there is a second launch window in late April through early
May.  Clear weather conditions are required at the ground observing sites. 
 
     Three-stage Black Brant X suborbital rockets will be used to loft
the barium payloads.  The Black Brant XB is a solid- propellant rocket
about 48 feet long and 18 inches in diameter. 
 
     There will be two barium releases from each rocket payload, one
before and one after apogee.  The two explosive releases will occur
from each payload at altitudes of 483 and 555 miles over the center of
Hudson Bay. 
 
     The time of the launches is selected so the releases occur either
in the post-twilight or pre-dawn period when the payloads are in
sunlight but observers on the ground are in darkness. Project
officials expect them to be visible as far away as Chicago. 
 
     Following each release, the barium is quickly ionized (becomes
electrically charged) by the sunlight.  The ejected barium first
appears greenish-white in color, becomes yellowish and then turns to a
purplish hue.  The newly-created barium ions spiral around magnetic
field lines and rapidly move along the magnetic field lines away from Earth. 
 
     Each release will produce two luminous streaks of barium ions
which absorb and re-emit sunlight.  One is a "pencil like" beam of
ions that will travel rapidly to altitudes greater than 12,425 miles
above Earth's surface.  The other streak does not have the high
velocity of the first and will rise to altitudes of only 1243 to 1864
miles .  The fast, high altitude streak probably will not be visible
to the naked eye after about 5 minutes.  The lower altitude low
velocity streak will remain visible for 20 or more minutes. 
 
     The "pencil-like" beams of barium ions will be tracked by
electronic intensified cameras from sites located at Churchill and
Gillam, Canada, and Los Alamos, N.M,; Houston; Richmond Hill, Pa.; and
Millstone Hill, Mass.  Scanning photometers will observe from Calgary,
Canada, and from Richland, Wash.; Seeley Lake, Mont.; Boulder, Colo.;
and Channing, Mich. 
 
     The U.S. observing teams come from the Goddard Space Flight
Center, Johnson Space Center, Los Alamos National Laboratory, Battelle
Pacific Northwest Laboratory, Naval Research Laboratory, Technology
International Corp., University of Alaska, Boston University, plus a
team from University College, London. 
 
     In the other two missions of the 1989 campaign, Nike-Orion
rockets will carry a cryogenic whole-air sampler (CWAS) payload
weighing over 400 pounds into the upper stratosphere to study the
polar ozone problem and the greenhouse effect. 
 
     The CWAS payload was developed by the University of Pittsburgh
for NASA's Upper Atmosphere Research Program to investigate the
sources and losses of carbon dioxide, Nitrous Oxide, Nitric Oxide and
Methane and other trace constituents that play a role in the ozone
chemistry of the middle atmosphere over an altitude range of 19-47
miles.  The payload also will provide an accurate technique for
calibrating UARS, a remote-sensing satellite scheduled to be launched
by NASA from the Shuttle during September 1991. 
 
     The CWAS experiments are part of a major NASA effort to study the
chemistry of the lower atmosphere at northern latitudes.  These
launches will complement the extensive aircraft and ground-based
observations by NASA's polar expedition to Norway this winter. 
 
     The CWAS payload measures the density and altitude distribution
of the major and minor chemical species in air. This objective is
accomplished by collecting large whole-air samples during the upleg
portion of the flight, returning them to the Earth by parachute and
ultimately analyzing the samples at the University of Pittsburgh.  A
novel refrigeration technique is used to freeze the air entering the
payload in specially-prepared collection cells kept at -436 degrees F.
during flight. 
 
     W. A. Brence, Wallops Flight Facility (WFF), is the NASA campaign
manager.  Dr. Robert Hoffman, NASA Goddard Space Flight Center,
Greenbelt, Md.,is the principal investigator for the two Black Brant X
launches, and Dave Kotsifakis is the NASA WFF payload manager.  Dr.
Edward C. Zipf, University of Pittsburgh, is the principal
investigator for the two Nike-Orion launches. Bruce Scott is the NASA
WFF payload manger. 
  

        From a letter I received a short time ago:

        Regarding the "colored cloud" experiment I posted a little while
    ago:  I just read a UPI notice in the Boston Globe that says the
    experiment, using a rocket full of barium, is to take place SUNDAY
    night at 9:40 PM. The rocket will take off from Wallops Island in VA
    (RAP has seen this once before, he says), and the rocket will travel
    to about 300 miles up before exploding and creating a huge green and
    purple cloud.  The news item also says the cloud should be visible "from 
    the Atlantic Seaboard all the way to Ohio" in a velocity experiment. 

        If anyone else happens to grab a paper, perhaps we could get a
    confirmation on the date and time? 

    	The artificial aurora experiment, postponed from the past weekend,
    is now scheduled to be launched tonight at 9:25 pm EST.
    
    	Larry
    

    I just watched the WBZ TV4 news in Boston.  Bruce Sweglier (sp?)
    said that the launch was scheduled for 9:29 EST (close enough),
    but that he thought that they may not go, due to clouds South of
    us here in New England.
    
    I'll probably be out with the telescope tonight looking at M44 and
    M67, so I'll be out there anyway.
    
    Joe
    

I heard via the office mail grapevine that it was postponed again last night
and is rescheduled for tonite at 9:39.

Burns

        From a report by Topher Cooper:                       

    From today's Globe (4/26).  It will be launched at 9:50 PM sometime
    this week or next, when viewing conditions allow.  It will remain
    visible about 20 minutes.  It is said that it will look like a bright
    greenish-purple cloud and may be about 3 times the size of a full moon
    and may have a comet-like tail.  From Boston, it will appear in the
    south-southeast about 1/3 of the way above the horizon.
    
    It will be visible to the naked eye, but will be more interesting
    through binoculars.  The chief investigator, Roy Torbert of the UofNH,
    would like to hear detailed reports from anyone who observes it through
    binoculars (or, I would presume, through a home telescope).  The
    reports may be sent to him at the UNH-EOS Space Science Center, Science
    and Engineering Building, Hurham, NH 03824.
    
    My not-very-well-informed guess is that it will be photographable,
    using sensitive film and a relatively long exposure (with a tripod, of
    course).  Don't expect it to look as interesting as the "real thing".
    
    					Topher

Actually, the report said "visible" at 9:50 didn't it?  In any case, I did
not see anything.  The Weather Channel said there were t-storms and stuff
south of DC, so that may have included Wallops Island.

Anyone here anything definite?  I heard nothing on either TWC or CNN.

Burns

    I heard that it has been postponed until Sunday at the earliest.
    There was some comment about "technical difficulties" this time.
    
    Ken

    re .5/.6 - I had been wondering about the distinction between launch
    time and the actual time of experiment deployment being visible from
    the ground.  I had assumed that the times like 9:29 and 9:39 given on
    WBZ-TV were launch times, but I guess it's not really certain.  Any
    idea how long an interval between launch and deployment, I would assume
    no more than a couple of minutes? 

    did this thing go?  What's the scoop???
    
    jim