It is proposed to carry out slitless spectroscopy at ultraviolet wavelengths from orbit of meteoric debris associated with comets. The Eta Aquarid, Orionid/Halley, and the Persied/1962 862 Swift-Tuttle showers would be principal targets. Low light level, ultraviolet video technique will be used during the night side of the orbit in a wide field, earthward viewing mode. Data will be stored in compact video cassette recorders. The experiment may be configured as a GAS package or in the HITCHHIKER mode. The latter would allow flexible pointing capability beyond that offered by shuttle orientation of the GAS package, and doubling of the data record. The 1100 to 3200 A spectral region should show emissions of atomic, ionic, and molecular species of interest on cometary and solar system studies

Kubinec, William R.

Nuth, Joseph A.

Wdowiak, Thomas J.

English

NASA Technical Reports Server

N89-15031 - 
ULTRAVIOLET SPECTROSCOPY OF METEORIC DEBRIS: IN SITU CALIBRATION 
EXPERIMENTS FROM EARTH ORBIT 
Joseph A. Nuth (NASINRC), Thomas J. Wdowiak (Univ. Alabama at 
Birmingham), William R. Kubinec (College of Charleston) 
Introduction. We propose to carry out slitless spectroscopy at 
ultraviolet wavelengths from orbit of meteoric debris associated with 
comets. The Eta Aquarid and Orionid/Halley and the Perseid11962 862  
Swift-Tuttle showers would be our principal targets. Low light level, 
ultraviolet video techniques will be used during the night side of the 
orbit in a wide field, earthward viewing mode. Data will be stored in 
compact video cassette recorders. The experiment may be configured as a 
GAS package o r  in the HITCHHIKER mode. The latter would allow flexible 
pointing capability beyond that offered by shuttle orientation of the 
GAS package, and doubling of the data record. The 1100-3200 A spectral 
region should show emissions of atomic, ionic, and molecular species of 
interest on cometary and solar system studies. 
A major problem at the present time is an inability to accurately 
convert observed meteoric spectral intensities into compositional infor- 
mation. This problem could be circumvented and a significant amount of 
data on fundamental meteoric phenomenon could be obtained by the high- 
velocity injection of well characterized projectiles into the earth's 
upper atmosphere. This could be accomplished quite easily i f  a rail gun 
were available on the space station as part of the microgravity crater- 
ing facility (or for other reasons). Projectiles launched from a rail 
gun in earth orbit could enter the atmosphere at velocities as high as 
25  km/s. Optimal viewing of such artificial meteors could be achieved 
if the gun and detector systems were located on separate platforms 
several hundred kilometers apart. 
Discussion. Analysis of middle to far ultraviolet spectral data of 
meteoric debris of cometary origin has yet to be carried out. Objec- 
tives of such a study include the observation of many atomic species, 
both neutral and ionized, including the strong feature due to MgI at 
2850A and the strong blend at 2800A due t o  MgII and MnI. An interesting 
possible metal emission is that of Be1 at 2349A. 
Carbon is an expected constituent of comet-associated meteors. 
Though spectral features can exist in the visible region, carbon cannot 
be observed due to masking, principally by i ron .  The 1000-2000A region 
should be relatively free of FeI and FeII emission allowing observation 
of CI at 1193A, CI at 1330A, CI at 1561, and CI at 16578. In addition, 
strong Si1 and Si11 emissions exist in the region suggesting determina- 
tion of the CISi ratio. Lines of Si0 could also be observed at 1310A. 
Lyman alpha emission occurs at 1215A due to hydrogen from dissociat- 
ing H 0 and hydrocarbons. The video technique allows examination of the 
temporal development of the expected strong Lyman alpha emission from 
cometary sources. Sulfur lines occur at 1807A and 1820A; phosphorus 
lines occur at 1672A, 1675A, 1680A, and 1775A. Sulfur is a relatively 
abundant component of carbonaceous chondrites and its existence in come- 
tary debris is of interest. The recent IUE observations by the Univ. of  
2 
A-80 
https://ntrs.nasa.gov/search.jsp?R=19890005660 2020-03-20T04:54:27+00:00Z
W SPECTROSCOPY OF METEORIC DEBRIS 
J. A. Nuth, T. J. Wdowiak, and W. R. Kubinec 
Maryland group, led by A'Hearn revealing dimer sulfur (S2) emissions 
between 28208 and 3090A of comet IUS-Araki-Alcock, makes the search f o r  
meteor sulfur all the more interesting. 
Instrumentation. The experiment mgkes useoof high speed ( f  ratio of 
0.75) reflecting optics viewing a 12 by 12 field with an objective 
grating. The imaging detector is an intensified solid-state array 
having the following characteristics: 
1100-3200A 
UV intensified CID 
8.7 x 11.4 mm 
244 x 388 pixels 
6 ma/watt sens. (1500A) 
20 ma/watt sens. (2500A) 
CsTe/MgF p.c./wind. 
ex. ITT 8.4561 
The dispersing element would be a 300 l/mm grating blazed f o r  first 
order with a 250 A MgF protective coating. Fig. 1 displays the pro-  
posed optical configuration. 2 
In the GAS configuration, video data will be stored in a stack of up 
to four compact video cassette recorders. Depending upon recording 
speed, a total record duration for the four-stack would be eight to 
twenty-four hours. Because data is recorded for approximately twenty 
minutes per orbit, data would be gathered over twenty-four to seventy- 
two orbits. Control would be by microprocessor and total power required 
would be less than 1.2 KWH from a battery pack of less than 1 ft3and 100 
lb. 
A HITCHHIKER configuration would allow greater volume by utilizing 
shuttle power and additional GAS type containers for data storage. The 
optics/detector could then be gimbeled to allow some pointing capabil- 
ity. 
A-8 1 


Ultraviolet spectroscopy of meteoric debris: In situ calibration experiments from earth orbit

It is proposed to carry out slitless spectroscopy at ultraviolet wavelengths from orbit of meteoric debris associated with comets. The Eta Aquarid, Orionid/Halley, and the Persied/1962 862 Swift-Tuttle showers would be principal targets. Low light level, ultraviolet video technique will be used during night side of the orbit in a wide field, earthward viewing mode. Data will be stored in compact video cassette recorders. The experiment may be configured as a GAS package or in the HITCHHIKER mode. The latter would allow flexible pointing capability beyond that offered by shuttle orientation of the GAS package, and doubling of the data record. The 1100 to 3200 A spectral region should show emissions of atomic, ionic, and molecular species of interest on cometary and solar system studies

Wdowiak, T. J.

Kubinec, W. R.

Nuth, J. A., III

ULTRAVIOLET SPECTROSCOPY OF METEORIC DEBRIS: IN SITU CALIBRATION
EXPERIMENTS FROM EARTH ORBIT
Joseph A. Nuth (NAS/NRC), Thomas J. Wdowiak (Univ. Alabama at
Birmingham), William R. Kubinec (College of Charleston)
Introduction. We propose to carry out slitless spectroscopy at
ultraviolet wavelengths from orbit of meteoric debris associated with
comets. The Eta Aquarid and Orionid/Halley and the Perseid/1962 862
Swift-Tuttle showers would be our principal targets. Low light level,
ultraviolet video techniques will be used during the night side of the
orbit in a wide field, earthward viewing mode. Data will be stored in
compact video cassette recorders. The experiment may be configured as a
GAS package or in the HITCHHIKER mode. The latter would allow flexible
pointing capability beyond that offered by shuttle orientation of the
GAS package, and doubling of the data record. The 1100-3200 A spectral
region should show emissions of atomic, ionic, and molecular species of
interest on cometary and solar system studies.
A major problem at the present time is an inability to accurately
convert observed meteoric spectral intensities into compositional infor-
mation. This problem could be circumvented and a significant amount of
data on fundamental meteoric phenomenon could be obtained by the high-
velocity injection of well characterized projectiles into the earth's
upper atmosphere. This could be accomplished quite easily if a rail gun
were available on the space station as part of the microgravity crater-
ing facility (or for other reasons). Projectiles launched from a rail
gun in earth orbit could enter the atmosphere at velocities as high as
25 km/s. Optimal viewing of such artificial meteors could be achieved
if the gun and detector systems were located on separate platforms
several hundred kilometers apart.
Discussion. Analysis of middle to far ultraviolet spectral data of
meteoric debris of cometary origin has yet to be carried out. Objec-
tives of such a study include the observation of many atomic species,
both neutral and ionized, including the strong feature due to Mgl at
2850A and the strong blend at 2800A due to Mgll and Mnl. An interesting
possible metal emission is that of Bel at 2349A.
Carbon is an expected constituent of comet-associated meteors.
Though spectral features can exist in the visible region, carbon cannot
be observed due to masking, principally by iron. The IO00-2000A region
should be relatively free of Fel and Fell emission allowing observation
of CI at I193A, CI at 1330A, CI at 1561, and CI at 1657A. In addition,
strong Sil and Sill emissions exist in the region suggesting determina-
tion of the C/Si ratio. Lines of SiO could also be observed at 1310A.
Lyman alpha emission occurs at 1215A due to hydrogen from dissociat-
ing H20 and hydrocarbons. The video technique allows examination of the
temporal development of the expected strong Lyman alpha emission from
cometary sources. Sulfur lines occur at 1807A and 1820A; phosphorus
lines occur at 1672A, 1675A, 1680A, and 1775A. Sulfur is a relatively
abundant component of carbonaceous chondrites and its existence in come-
tary debris is of interest. The recent IUE observations by the Univ. of
6-41
https://ntrs.nasa.gov/search.jsp?R=19860017687 2020-03-20T14:26:59+00:00Z
UV SPECTROSCOPY OF METEORIC DEBRIS
J. A. Nuth, T. J. Wdowiak, and W. R. Kublnec
Maryland group, led by A'Hearn revealing dimer sulfur (S?) emissions
between 2820A and 3090A of comet IRAS-Araki-Alcock, makes th_ search for
meteor sulfur all the more interesting.
Instrumentation. The experiment makes use of high speed (f ratio of
0.75) reflecting optics viewing a 12° by 12° field with an objective
grating. The imaging detector is an intensified solid-state array
having the following characteristics:
II00-3200A 6 ma/watt sens. (1500A)
UV intensified CID 20 ma/watt sens. (2500A)
244 x 388 pixels CsTe/MgF 2 p.e./wlnd.
8.7 x 11.4 mm ex. ITT F.4561
The dispersing element would be a 300 I/mm grating blazed for first
order with a 250 A MgF 2 protective coating. Fig. 1 displays the pro-
posed optical configuration.
In the GAS configuration, video data will be stored in a stack of up
to four compact video cassette recorders. Depending upon recording
speed, a total record duration for the four-stack would be eight to
twenty-four hours. Because data is recorded for approximately twenty
minutes per orbit, data would be gathered over twenty-four to seventy-
two orbits. Control would be by microprocessor and total power required5
would be less than 1.2 KWH from a battery pack of less than I ft and i00
lb.
A HITCHHIKER configuration would allow greater volume by utilizing
shuttle power and additional GAS type containers for data storage. The
optlcs/detector could then be glmbeled to allow some pointing capabil-
ity.
' _ i IntensifiedCIDCamera
6-42


Ultraviolet spectroscopy of meteoric debris: In situ calibration experiments from earth orbit

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