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ELECTRONIC NEWSLETTER OF THE EUVE OBSERVATORY
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Vol. 7, No. 1 31 Jan 1997 ISSN 1065-3597
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(C) 1997, Regents of the University of California
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Notes from the Editor
=====================
by Brett A. Stroozas, EUVE Flight Operations Manager
Welcome to the electronic newsletter for NASA's Extreme Ultraviolet
Explorer (EUVE) satellite, compiled and published monthly by the
Center for EUV Astrophysics (CEA) at the University of California,
Berkeley (UCB). The contents of this issue of the EUVE electronic
newsletter are as follows:
1. EUVE Science News
1.1 Abstracts of Recently *Accepted* EUVE Papers
2. EUVE Science Operations News
2.1 EUVE Spacecraft in Safe-Hold Mode
2.2 Public GO/RAP Data Release for 1 Jan 1997
2.3 On-Line Access to EUVE
3. EUVE Outsourced Extended Mission Status Report
3.1 Mission Operations Review at GSFC
3.2 CEA FOT Fully Staffed
3.3 EPOC Systems Testing
To comment on or make suggestions for the EUVE electronic newsletter,
please send e-mail to ceanews@cea.berkeley.edu (Internet).
The EUVE observatory performed well throughout the month of Dec
1996, completing and/or beginning observations of the following Guest
Observer (GO) and Right-Angle Program (RAP) targets. For each target
is listed its name, spectral type, observation start date and time (in
day_of_year:hours_minutes GMT format), name of Principal Investigator
(PI), observation type/priority, and any relevant notes:
=======================================================================
Target SpT Start PI T Notes
=======================================================================
Sirius B WD:DA 332:00:40 (27 Nov) Holberg 1 EGO,SPI
EUVE J0858-002 NOID 342:18:00 (07 Dec) Lampton 2 EGO
HD 19373 G0V 342:18:00 (07 Dec) Portier 3 RAP
EUVE J2206+637 NOID 343:16:00 (08 Dec) Lampton 2 EGO
0633+1746 NeutSt 343:16:00 (08 Dec) Edelstein 3 RAP
EUVE J0908+326 NOID 344:14:05 (09 Dec) Lampton 2 EGO
EUVE J0249+099 NOID 344:14:05 (09 Dec) Lampton 3 RAP
EUVE J1100+344 NOID 345:12:15 (10 Dec) Lampton 2 EGO
EUVE J0424+15.4 NOID 345:12:15 (10 Dec) Craig 2 RAP
EUVE J0425+15.2 NOID 345:12:15 (10 Dec) Craig 2 RAP
NGC 4051 AGN:Sy 346:11:59 (11 Dec) Fruscione 1 EGO
AR UMa CV:AM 349:09:24 (14 Dec) Silber 1 EGO,TOO
WD 0549+158 WD:DAw 351:13:20 (16 Dec) Lallement 1 EGO,SPI
Moon SolSys 355:01:06 (20 Dec) Judge 1 EGO,TCO,MUL
WD 0549+158 WD:DAw 355:02:40 (20 Dec) Lallement 1 EGO,SPI
Moon SolSys 356:00:46 (21 Dec) Judge 1 EGO,TCO,MUL
HD 84737 G0.5Va 356:00:46 (21 Dec) Portier 3 RAP
WD 0549+158 WD:DAw 356:02:20 (21 Dec) Lallement 1 EGO,SPI
Moon SolSys 357:00:26 (22 Dec) Judge 1 EGO,TCO,MUL
WD 0549+158 WD:DAw 357:02:00 (22 Dec) Lallement 1 EGO,SPI
PC 0025+0447 M 357:22:31 (22 Dec) Stringfellow 2 EGO
Moon SolSys 358:00:06 (23 Dec) Judge 1 EGO,TCO,MUL
1025-07 NeutSt 358:00:06 (23 Dec) Edelstein 3 RAP
PC 0025+0447 M 358:01:40 (23 Dec) Stringfellow 2 EGO
Safehold ----- 358:20:08 (23 Dec) ------ - SAF
PC 0025+0047 M 360:03:10 (25 Dec) Stringfellow 2 EGO
Moon SolSys 361:21:11 (26 Dec) Judge 1 EGO,TCO,MUL
PC 0025+0047 M 361:22:46 (26 Dec) Stringfellow 2 EGO
Moon SolSys 362:22:25 (27 Dec) Judge 1 EGO,TCO,MUL
alpha Col B7IVe 362:23:50 (27 Dec) Peters 1 EGO
Moon SolSys 363:22:05 (28 Dec) Judge 1 EGO,TCO,MUL
alpha Col B7IVe 363:23:30 (28 Dec) Peters 1 EGO
Moon SolSys 364:21:45 (29 Dec) Judge 1 EGO,TCO,MUL
alpha Col B7IVe 364:23:10 (29 Dec) Peters 1 EGO
=======================================================================
Key to Notes:
EGO = Guest Observer observation
RAP = Right-Angle Program observation
MUL = Multiple pointings
TCO = Time-critical observation
TOO = Target of Opportunity
SPI = Spiral dithered observation
SAF = Spacecraft in Safe-Hold Mode
1. EUVE Science News
====================
1.1 Abstracts of Recently *Accepted* EUVE Papers
------------------------------------------------
Included below are abstracts of EUVE-related papers recently
*accepted* for publication. For those papers authored by CEA
personnel, the CEA publication numbers are indicated. Unless
otherwise noted, researchers may obtain preprints of the CEA papers by
sending an e-mail request containing the publication number(s) of
interest to pub@cea.berkeley.edu.
Researchers are encouraged to contribute *accepted* EUVE-related
abstracts for inclusion in future editions of this newsletter;
abstracts will also be posted under the CEA WWW site. Please send all
abstracts to archive@cea.berkeley.edu.
--------------------------------------------------------------
A SEARCH FOR HIDDEN WHITE DWARFS IN THE ROSAT EUV SURVEY
M.R. Burleigh, M.A. Barstow and T.A. Fleming
To appear in Monthly Notices of the Royal Astronomical Society.
The ROSAT WFC and EUVE surveys has provided us with evidence for
the existence of a previously unidentified sample of hot white dwarfs
(WD) in non-interacting binary systems, through the detection of EUV
and soft X-ray emission. These stars are hidden at optical wavelengths
due to their close proximity to much more luminous main sequence (MS)
companions (spectral type K or earlier). However, for companions of
spectral type ~A5 or later the white dwarfs are easily visible at
far-UV wavelengths, and can be identified in spectra taken by
IUE. Eleven white dwarf binary systems have previously been found in
this way from ROSAT, EUVE and IUE observations (e.g. Barstow et
al. 1994). In this paper we report the discovery of three more such
systems through our programmes in recent episodes of IUE. The new
binaries are HD2133, RE J0357+283 (whose existence was predicted by
Jeffries, Burleigh and Robb 1996), and BD+27 1888. In addition, we
have independently identified a fourth new WD+MS binary, RE J1027+322,
which has also been reported in the literature by Genova et
al. (1995), bringing the total number of such systems discovered as a
result of the EUV surveys to fifteen. We also discuss here six stars
which were observed as part of the programme, but where no white dwarf
companion was found. Four of these are coronally active. Finally, we
present an analysis of the WD+K0IV binary HD18131 (Vennes et
al. 1995), which includes the ROSAT PSPC X-ray data.
--------------------------------------------------------------
AN ACTIVE K0 IV-V STAR AND A HOT WHITE DWARF (EUVE J0702+129) IN A
WIDE BINARY
S. Vennes, D.J. Christian, M. Mathioudakis, and J.G. Doyle
To appear in Astronomy & Astrophysics Letters. [CEA publication #778]
We present far ultraviolet and optical spectroscopy of the Extreme
Ultraviolet Explorer (EUVE) survey source EUVE J0702+129 revealing a
composite K0 star plus DA white dwarf spectrum. The International
Ultraviolet Explorer spectra show continuum emission from a hot white
dwarf (T_eff = 30-40,000 K) and a rising contribution from the K0 star
at lambda >= 2500 A. High resolution optical spectroscopy uncovers a
high level of activity with strong H-alpha and Ca H&K emission;
application of the Wilson-Bappu relation indicates that the secondary
star is slightly above the main sequence (K0 IV-V). Both objects are
found at a distance of ~130 pc and they likely constitute a physical
pair. The EUV emission is dominated by the white dwarf, but the
late-type star certainly contributes at higher energy. An interesting
parallel is drawn with other DA+K0 pairs with moderately active
secondaries such as HD 18131 and HR 1608. The present discovery as
well as other recent ones demonstrate the existence of a large
population of white dwarfs hidden by evolved companions (III-IV).
--------------------------------------------------------------
2. EUVE Science Operations News
===============================
2.1 EUVE Spacecraft in Safe-Hold Mode
-------------------------------------
by Brett Stroozas, EUVE Flight Operations Manager (based on a
report by Kevin Hartnett, EUVE Mission Director at GSFC)
The EUVE spacecraft entered Safe-Hold Mode (SHM) on Mon, 23 Dec
1996, at 20:08pm GMT (12:08pm PST). A Goddard Space Flight Center
(GSFC) Flight Controller mistakenly initiated a command sequence to
perform a hardware dump of on-board computer (OBC) memory while the
OBC was still running. The goal of the activity was to validate the
ability of the new Transportable Payload Operations Control Center
(TPOCC) ground system to properly initiate and process such dumps. In
response to this improper command the on-board safe-hold processor
performed flawlessly -- halting the OBC, re-orienting the spacecraft
to the sun-line, and moving the solar arrays to maximize power.
By 16:00 GMT (8:00am PST) on Tue morning, 24 Dec, initial recovery
activities to OBC control were underway. With the fortunate
availability of nearly continuous TDRSS Multiple Access (MA) coverage,
and the certain knowledge that there were no hardware failures
on-board the spacecraft, the decision was made to push ahead and
recover fully to Inertial Mode, which was entered at 19:45 GMT
(11:45am PST). Had we not done so, EUVE would have remained in
safehold for another couple days due to personnel availability over
the Christmas Holidays.
The science payload was reconfigured from SHM during the afternoon
of Tue, 24 Dec, and was again taking GO data by 8pm PST that evening;
because of the Christmas Holidays the scanning telescopes were not
returned to nominal configuration until Fri, 27 Dec.
The GO target PC 0025+0447 was affected by the SHM incident, as well
as one (of nine) orbits of a multiple pointing Moon observation.
2.2 Public GO/RAP Data Release for 1 Feb 1997
---------------------------------------------
by Dr. Nahide Craig, EUVE User Support Scientist
The table below lists the GO/RAP observations that become public on
1 Feb 1997. For each observation is given the target name, the
approximate exposure time in ksec, the GMT start/end dates, the
target's spectral type, and the data identification code (GO and RAP
data are marked accordingly). All public data sets can be ordered
from the archive via WWW and electronic or postal mail (see addresses
below). Please be sure to include in your order the DataID(s) of
interest. Processed data sets are shipped via postal mail on 8mm tape
or (if requested) on CD-ROM.
The data rights policies for observations state that Principal
Investigators (PIs) have proprietary rights to the data for a given
period of time from the date (s)he receives it. It is often the case
that long observations are broken up over many months; e.g., an
observation approved for 60 ksec may actually be observed for 10 ksec
one month, 20 ksec the next, and 30 ksec three months later. In such
cases the proprietary period begins after the PI is sent the final
piece of the completed observation.
===============================================================
Target ~Exp Observation Dates SpT DataID
Name (ksec) Start End
===============================================================
GO DATA SETS AVAILABLE 1 FEB 1997:
***** Cycle 4 Targets *****
EUVE J1925-565 90 15 Jun - 19 Jun 1996 XRS go0485
EUVE J1925-565 44 25 Jun - 26 Jun 1996 XRS go0486
Jupiter 155 19 Jun - 24 Jun 1996 SolSys go0487
NGC 5548 156 26 Jun - 02 Jul 1996 AGN:Sy1 go0488
NGC 5548 156 02 Jul - 07 Jul 1996 AGN:Sy1 go0489
Ton S180 130 08 Jul - 12 Jul 1996 AGN:Sy1 go0490
Ton S180 130 12 Jul - 17 Jul 1996 AGN:Sy1 go0491
***** Cycle 3 Targets *****
Capella 51 30 Nov - 02 Dec 1995 G5IIIe go0492
Capella 51 02 Dec - 04 Dec 1995 G5IIIe go0493
RE J1016-052 61 04 Dec - 06 Dec 1995 WD:DA go0494
EK Dra 94 10 Dec - 13 Dec 1995 F8 go0495
Moon 2 13 Dec - 13 Dec 1995 SolSys go0496
MRK 142 9 13 Dec - 13 Dec 1995 AGN:Sy1 go0497
EUVE J0503+231 1 13 Dec - 13 Dec 1995 NOID go0498
beta CMa 64 26 Nov - 28 Nov 1995 B1II/III go0499
beta CMa 44 13 Dec - 15 Dec 1995 B1II/III go0500
beta CMa 55 29 Dec - 31 Dec 1995 B1II/III go0501
NGC 1851 37 15 Dec - 16 Dec 1995 GlobClus go0502
EUVE J0720-317 100 16 Dec - 20 Dec 1995 WD:DA go0503
EUVE J0720-317 5 20 Dec - 20 Dec 1995 WD:DA go0504
zeta Pup 100 20 Dec - 24 Dec 1995 O5Ia go0505
zeta Pup 41 24 Dec - 25 Dec 1995 O5Ia go0506
Coma Cluster 84 25 Dec - 28 Dec 1995 ClusGal go0507
EUVE J1034+073 20 28 Dec - 29 Dec 1995 NOID go0508
GJ 354.1 100 31 Dec - 03 Jan 1996 K0 go5009
GJ 354.1 100 03 Jan - 07 Jan 1996 K0 go0510
GJ 354.1 100 07 Jan - 10 Jan 1996 K0 go0511
GJ 354.1 14 10 Jan - 11 Jan 1996 K0 go0512
Moon 2 11 Jan - 11 Jan 1996 SolSys go0513
NGC 5457 56 11 Jan - 13 Jan 1996 Gal go0514
RE J0751+144 100 13 Jan - 16 Jan 1996 CV:DQ go0515
RE J0751+144 85 16 Jan - 19 Jan 1996 CV:DQ go0516
ALEXIS Transient 31 19 Jan - 21 Jan 1996 NOID go0517
IRAS 13349+2438 12 21 Jan - 21 Jan 1996 AGN:QSO go0518
RAP DATA SETS AVAILABLE 1 FEB 1997:
ALEXIS Transient 62 03 Jun - 05 Jun 1996 NOID rap0071
EUVE J1854-324 110 07 Jun - 11 Jun 1996 NOID rap0072
EUVE J1706-450 36 11 Jun - 12 Jun 1996 NOID rap0073
WGA J1559+27 86 12 Jun - 15 Jun 1996 NOID rap0074
1908+0734 260 08 Jul - 17 Jul 1996 Pulsar rap0075
================================================================
2.3 On-Line Access to EUVE
--------------------------
Listed below are the various methods for on-line access to EUVE:
o CEA World Wide Web (WWW)
URL http://www.cea.berkeley.edu/
telnet www.cea.berkeley.edu 200 (for those without a WWW browser)
o anonymous FTP
ftp ftp.cea.berkeley.edu
Name: anonymous
Password: type_your_full_e-mail_address
o anonymous gopher
gopher ftp.cea.berkeley.edu
o EUVE Electronic Newsletters
Past issues -- available via the CEA WWW site
Subscriptions -- mail majordomo@cea.berkeley.edu ("subscribe
euvenews")
Post message (moderated) to all subscribers:
mail euvenews@cea.berkeley.edu
o GI Program
Are you interested in finding out about or using EUVE data? Do
you need help in understanding EUVE data sets? Do you need help
in using the available EUVE data analysis software tools? If you
answer "yes" to any of the above, the Guest Investigator (GI)
Program at CEA can help YOU! For more information see the CEA
WWW site or contact the Archive (archive@cea.berkeley.edu).
o Public RAP
The Public Right Angle Program (RAP) is a simple and easy method
for researchers to propose for long-exposure EUVE imaging data.
For more information on the Public RAP and the simple proposal
process see the CEA WWW site or contact the EGO Center
(egoinfo@cea.berkeley.edu). Mail all proposals to
euverap@cea.berkeley.edu.
o Contact information for the EUVE Science Archive or EGO Center:
Center for EUV Astrophysics
2150 Kittredge St.
Berkeley, CA 94720-5030
510-642-3032 (voice)
510-643-5660 (fax)
archive@cea.berkeley.edu
egoinfo@cea.berkeley.edu
3. EUVE Outsourced Extended Mission Status Report
=================================================
by Brett Stroozas, EUVE Flight Operations Manager
Work continues to outsource EUVE Explorer Platform (EP) spacecraft
operations from GSFC to the EUVE Platform Operations Center (EPOC) at
CEA. Upon completion of the operations handover, which is scheduled
for Feb 1997, the EUVE Outsourced Extended Mission (OEM) will
commence. The following sections describe some of the outsourcing
highlights from Dec 1996.
3.1 Mission Operations Review at GSFC
-------------------------------------
On 6 Dec 1996 an EUVE OEM Mission Operations Review (MOR) was held
at GSFC. Brett Stroozas and George Kaplan of CEA traveled to GSFC and
presented material on the outsourcing: overall planning; CEA Flight
Operations Team (FOT) staffing and training; EPOC design,
implementation, and testing; etc. Outstanding issues and concerns
were highlighted and performance criteria were outlined for the
operations handover. The review was attended by a five-person GSFC
Review Panel and ~30 additional GSFC personnel that are affiliated
with the EUVE Project. The review was very successful and GSFC
personnel were quite satisfied with CEA's plans and overall progress
to date. The Review Panel wrote up and distributed to CEA some Review
Item Discrepancies (RIDs), which outline a number of mostly minor
issues that remain to be addressed before the completion of the
handover of operations from GSFC to CEA. CEA has taken these RIDs as
action items and has begun working to address them. In all, the final
operations handover from GSFC to CEA is still on schedule for mid- to
late-Feb 1997.
3.2 CEA FOT Fully Staffed
-------------------------
By mid-Dec 1996 the final hiring activities were completed for
CEA's FOT. The fully staffed eight-person CEA FOT is composed of the
following:
+---------------------------------------------------------------------+
| FOT Member's FOT Member's |
| Name Responsibility |
+---------------------------------------------------------------------+
| Rob Nevitt EUVE Platform Operations Manager/Lead Systems |
| Engineer |
| Chris Smith EUVE Attitude Control Subsystem (ACS) Engineer |
| Greg Picard EUVE Communications & Data Handling (C&DH) |
| Subsystem Engineer |
| Mark Lewis EUVE Power and Thermal (P&T) Subsystem |
| Engineer |
| Sriram Chelluri EUVE Ground Systems Engineer |
| Marty Eckert EUVE Spacecraft Controller/Scheduler |
| John McDonald EUVE Spacecraft Controller/Scheduler |
| Jeremy Thorsness EUVE Spacecraft Controller/Scheduler |
+---------------------------------------------------------------------+
By the end of Dec six of the eight FOT members had completed an
extensive one- or two-month training period at GSFC with the incumbent
Lockheed-Martin FOT; the other two FOT members (John and Jeremy) are
currently training at GSFC and will return to CEA in early Feb 1997.
3.3 EPOC Systems Testing
------------------------
The month of Dec 1996 was an extremely busy one for testing and
validating the EPOC ground systems. A number of formal and informal
tests were conducted to validate the various communications links,
ground system components, and training of CEA FOT personnel. The
following subsections describe some of the highlights of these testing
activities.
3.3.1 TDRSS Scheduling Tests
The EUVE spacecraft communicates to the ground via NASA's Tracking
and Data Relay Satellite System (TDRSS), which is managed by GSFC's
Network Control Center (NCC). The FOT schedules real-time contacts
with the spacecraft by interfacing with the NCC for TDRS time.
On 5 Dec 1996 a successful engineering interface (EIF) test was
conducted with the NCC for the purpose of validating the relevant
communications lines and the receipt and transmission of the proper
ground control message requests (a.k.a. GCMRs) and acknowledgments.
This test confirmed the schedule-related operations of CEA's TPOCC
system.
An additional EIF test was conducted with the NCC on 30 Dec. The
purpose of this test was to validate proper communication of TDRSS
scheduling information between NCC and CEA. This test was also very
successful. In addition to validating the CEA/NCC communications
interfaces, this test served to validate the following EPOC ground
system components: EP Planning System (EPPS), User Planning System
(UPS), and Flight Dynamics Facility Orbital and Mission Aids
Transformation System (FORMATS).
As a result of the above tests CEA was able to demonstrate its
readiness to begin the scheduling shadow operations period in early
Jan 1997; details on this will appear in the next newsletter.
3.3.2 Command and Telemetry Tests
Command and telemetry tests were conducted throughout the month of
Dec 1996. Although the majority of the testing was done using the
GSFC EP simulator, the EPOC FOT also conducted live commanding of the
spacecraft in orbit.
On 3 Dec 1996 an initial command test was conducted between the
EPOC and the EP in orbit. This test was a complete success! The
EPOC, via the TPOCC command and control system, sent the following
commands to the EP: a single noop (no-operation), a string of five
buffered noops, and three tape recorder dump speed commands. All
commands executed properly, returning the appropriate telemetry
readings and incrementation of the command counter. This initial
end-to-end command and telemetry test provided validation that all of
the relevant systems were properly configured. Similar command and
telemetry tests were conducted during the subsequent two weeks.
3.3.3 Three-Day EPOC/FOT "Stress" Test
A three-day EPOC "stress" test was held 17-19 Dec 1996. The
purpose of this test was to stress both the EPOC ground systems and
FOT personnel by having CEA fly the spacecraft during this time. The
results of the stress test were as follows:
o Day 1 (17 Dec) -- This day was only marginally successful. Because
of problems with the command communications channel CEA was only
able to complete about half of the normal daily duties (i.e., tape
recorder management and command/table loads/dumps).
o Day 2 (18 Dec) -- This day was much more successful. Once the
command channel problems of the previous day were resolved CEA was
able to complete most of the normal daily activities along with a
few extras (e.g., OBC memory dumps). Unfortunately, CEA
experienced a variety of problems with its TPOCC system that
hampered overall productivity.
o Day 3 (19 Dec) -- This day was a complete success. Once the TPOCC
problems of the previous day were resolved CEA was able to complete
all of the regular daily activities, plus a few extras (e.g.,
payload commanding, OBC memory dumps, and an engineering format
test).
Overall, the stress test was an excellent experience. The EPOC ground
systems were sufficiently stressed to identify areas that need
additional work. The CEA FOT personnel obtained valuable experience
in routine activities as well as in anomaly trouble-shooting and
resolution.
---------------------------------------------------------------------------
The EUVE Electronic Newsletter is issued by the Center for Extreme
Ultraviolet Astrophysics, University of California, Berkeley, CA
94720, USA. The opinions expressed are those of the authors. EUVE
Principal Investigators and Newsletter Publishers: Dr. Roger F.
Malina and Professor Stuart Bowyer. EUVE Flight Operations Manager
and Newsletter Editor: Brett A. Stroozas. Funded by NASA/UCB
Cooperative Agreement NCC5-138. Send newsletter correspondence to
ceanews@cea.berkeley.edu.
The EUVE project is managed by NASA's GSFC: Paul Pashby, GSFC
Project Manager; Dr. Yoji Kondo, Project Scientist; Dr. Ronald
Oliversen, Deputy Project Scientist; Mr. Kevin Hartnett, Mission
Director. NASA HQ: Dr. Guenter Riegler, Program Manager.
Information on the EUVE GO Program is available from Dr. Ron
Oliversen, Mail Code 681, GSFC, Greenbelt, MD 20771 at (301)
286-6290 or e-mail to euve@stars.span.nasa.gov.
END-----------EUVE------------ELECTRONIC---------------NEWS-------------END
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