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Another fireball was observed over Vancouver Island, Washington State 
and mainland British Columbia at 21:22 PDT on April 22. We would be 
interested in receiving any reports on this fireball. Information 
required is as follows:
 
Your Longitude and Latitude from a topo survey map or GPS reading.
Compass Direction of first sighting, corrected to true north Elevation 
above the horizon measured with a clinometer or similar device Compass 
Direction of last sighting, corrected to true north Elevation above 
horizon, as noted above.
 
Any photographs or video tapes would be most helpful. We will not pay 
for these however as is requested by one individual who claims he has a 
tape. Anyone who cooperates will be given credit in a scientific 
report.
 
Forward reports to : epmajden@mars.ark.com
 
Thanks for your help:  Ed
------------------------------------------------------------------------------
Edward Majden                         epmajden@mars.ark.com
1491 Burgess Road                     Meteor Spectroscopy
Courtenay, B.C.                       AMS Affiliate
CANADA  V9N-5R8                       MIAC Associate

======================================
(3) SPECIAL PUBLICATION ON THE 1999 NEAR SPACECRAFT ON ITS RENDEZVOUS 
    WITH ASTEROID 433 EROS 

A.F. Cheng, R.W. Farquhar & A.G. Santo: NEAR overview. JOHNS HOPKINS 
APL TECHNICAL DIGEST, 1998, Vol.19, No.2, pp. 95-106

APL, PLANETARY SCIENCE SECTION, LAUREL, MD, 20723

The Near Earth Asteroid Rendezvous (NEAR) mission inaugurates NASA's 
Discovery Program. It will be the first to orbit an asteroid and will 
make the first comprehensive scientific measurements of an asteroid's 
surface composition, geology, physical properties, and internal 
structure. NEAR was launched successfully on 17 February 1996 aboard a 
Delta II-7925. It made the first reconnaissance of a C-type asteroid 
during its flyby of the main-belt asteroid 253 Mathilde in June 1997 
and will orbit the unusually large near-Earth asteroid 433 Eros for 
about a year at a minimum orbit radius of about 35 km from the center 
of the asteroid. NEAR will obtain new information on the nature and 
evolution of asteroids, improve our understanding of planetary 
formation processes in the early solar system, and clarify the 
relationship between asteroids and meteorites. The NEAR Mission 
Operations Center and Science Data Center are both located at APL. The 
latter will maintain the entire NEAR data set on-line and will make 
data from all instruments accessible over the Internet to every member 
of the NEAR science team. Copyright 1998, Institute for Scientific 
Information Inc.

===========================
(4) THE NEAR MULTISPECTRAL IMAGER

S.E. Hawkins: The NEAR Multispectral Imager. JOHNS HOPKINS APL 
TECHNICAL DIGEST, 1998, Vol.19, No.2, pp.107-114

The Multispectral Imager, one of the primary instruments on the Near 
Earth Asteroid Rendezvous (NEAR) spacecraft, uses a five-element 
refractive optics telescope, an eight-position filter wheel, and a 
charge-coupled device detector to acquire images over its sensitive 
wavelength range of approximate to 400-1100 nm. The camera operates at 
a frame rate of 1 Hz, and the detector is passively cooled. The primary 
science objectives of the Multispectral Imager are to determine the 
morphology and composition of the surface of asteroid 433 Eros. The 
camera will have a critical role in navigating to the asteroid. Seven 
narrowband spectral filters have been selected to provide multicolor 
imaging for comparative studies with previous observations of asteroids 
in the same class as Eros. The eighth filter is broadband and will be 
used for optical navigation. The Multispectral Imager has a focal 
length of 168 mm and a 2.93 x 2.25 degrees field of view. The spatial 
resolution of the instrument is 16.1 x 9.5 m at a range of 100 km. An 
overview of the instrument is presented, and design parameters and 
tradeoffs are discussed in the context of the fast-paced, low-cost 
Discovery Program. Copyright 1998, Institute for Scientific Information 
Inc.

==============================
(5) THE DESIGN AND TESTING OF THE NEAR SPACECRAFT

T.J. Hartka & D.F. Persons: The design and testing of the NEAR 
spacecraft structure and mechanisms. JOHNS HOPKINS APL TECHNICAL 
DIGEST, 1998, Vol.19, No.2, pp.163-173

This article describes the primary structure and mechanisms of the Near 
Earth Asteroid Rendezvous (NEAR) spacecraft. Presented are design 
requirements as well as a description of the primary structure and 
mechanisms to meet those requirements. The test philosophy for this 
cost-and schedule-driven program is outlined along with a summary of 
the test flow and results. The structure and mechanisms were designed, 
assembled, and tested at APL, with most of the structure manufacturing 
subcontracted. Testing continued at Goddard Space Flight Center, and 
the final spin balance test was performed at Kennedy Space Center.
Copyright 1998, Institute for Scientific Information Inc.

===========================
(6) THE NEAR SOLID-STATE DATA RECORDERS

R.K. Burek: The NEAR solid-state data recorders. JOHNS HOPKINS APL 
TECHNICAL DIGEST, 1998, Vol.19, No.2, pp.235-240

APL, DEPARTMENT OF SPACE, SIGNAL PROC SECTION, LAUREL, MD, 20723

Data recorders make it possible for the Near Earth Asteroid Rendezvous 
(NEAR) spacecraft to delay and slow the transmission of information to 
Earth, thereby accommodating the temporal and bandwidth limitations of 
the communications link. NEAR is the first spacecraft developed by the 
Applied Physics Laboratory to employ solid-state recorders, supplanting 
magnetic tape recorders used previously. Also, the 132 dynamic 
random-access memory devices, which are at the heart of the NEAR 
recorders, constitute the first large-scale use of plastic encapsulated 
microcircuits on a Laboratory spacecraft. Earlier spacecraft relied 
almost exclusively on hermetically packaged microcircuits. Several 
measures, including two layers of error detection and correction, were 
taken to mitigate the effects of single-event upsets that may be 
induced by charged particles in space. Copyright 1998, Institute for 
Scientific Information Inc.

======================
(7) COOPERATIVE FABRICATION OF THE NEAR SPACECRAFT

J.R. Dettmer: Cooperative fabrication of the NEAR spacecraft. JOHNS 
HOPKINS APL TECHNICAL DIGEST, 1998, Vol.19, No.2, pp.241-246

APL, ELECTRONIC SERVICE GROUP, LAUREL, MD, 20723

Cooperative fabrication was a key factor in building the Near Earth 
Asteroid Rendezvous (NEAR) spacecraft within the cost and schedule 
constraints dictated by the NASA Discovery Program. Because many of the 
traditional barriers between the engineering and the fabrication teams 
were avoided on NEAR, APL reaped the benefits of cooperative planning, 
design for ease of fabrication and assembly, and team problem solving. 
The result was a unified and high-spirited team focused on 
accomplishing the task. That teamwork, in combination with many of the 
enabling technologies within the fabrication organization, allowed APL 
to meet NEAR's cost, schedule, reliability, and performance goals.
Copyright 1998, Institute for Scientific Information Inc.

========================
(8) THE NEAR SCIENCE DATA CENTER

K.J. Heeres, D.B. Holland & A.F. Cheng: The NEAR Science Data Center. 
JOHNS HOPKINS APL TECHNICAL DIGEST, 1998, Vol.19, No.2, pp.257-266

APL, DEPARTMENT OF SPACE, TIMED MISSION DATA CTR, LAUREL, MD, 20723

The Near Earth Asteroid Rendezvous (NEAR) Science Data Center serves as 
the central site for common data processing activities needed by the 
NEAR science teams and the scientific community. The Center provides 
instrument and spacecraft data to the science teams from around. the 
world and redistributes science products produced by those teams, 
allowing the teams to focus on analysis. These data and the 
accompanying documentation are available at 
http://sd-www.jhuapl.edu/NEAR/. In addition, the Science Data Center is 
responsible for archiving spacecraft, instrument, and science data to 
the Planetary Data System. Copyright 1998, Institute for Scientific 
Information Inc.

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