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Eyepiece Views: January, 2002
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THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
25 Birch Street, Cambridge, MA 02138 USA
Tel. 617-354-0484 Fax 617-354-0665
http://www.aavso.org
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E Y E P I E C E V I E W S
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January, 2002 Vol 2 No 1
Table of Contents
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1. Introduction
2. 0324+43 GK PERSEI - Observing Campaign
3. Comments on LPV'S by Janet Mattei
4. Comments on CV's by Mike Simonsen
5. SN 2001ig in NGC 7424
6. The Teapot and the Kitchen Window
7. HOAFUN 2 for Windows
8. Variable Star of the Month Summary
9. The AAVSO Variable Star Chart Program 6-Month Plan
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1. WELCOME TO 2002
For most of us, the year 2002 begins on January 1. Besides being an
interesting palindrome, what else does 2002 offer? For the AAVSO, quite
a bit is in store. First, there is the spring meeting in Hawaii. Start
saving now because you won't want to miss out on an high-energy
astrophysics workshop, CV workshop, and trips to Mauna Kea. Secondly,
we are resolved to overhaul the AAVSO variable star chart program this
year to make it more responsive to your needs. At the end of this issue
of Eyepiece Views is a quick summary of some of the things we hope to
achieve in that area. Finally, 2002 offers what the beginning of every
year offers: hope for more clear skies than last year!
Looking back, 2001 offered much for us to be greatful. The AAVSO has
continued to grow by leaps and bounds, especially in regards to our
international observers and members. Last year new technology and
resources became available for just about every observing program in
the organization. But it all seems to be just a little bit diminished
in excitement due to the shadow of many of the events that have occured
in the past year. We would like to suggest that when things get you
down, just look up at the majesty of the stars and revel in their
beauty. And when you are finished and ready to come back down to Earth,
think about how all the variable star organizations in the world
cooperate together. If only our political and societal leaders could
follow our model. There may not be harmony with lines on a map right
now, but there is harmony in the skies and fellowship among variable
star observers of all nations.
Hang in there and look forward to a much more optimistic greeting in
the Volume 3, No 1 issue of Eyepiece views, due about 365 days from
now. :)
Good observing!
Gamze Menali,AAVSO Technical Assistant (MGQ)
Aaron Price, AAVSO Technical Assistant (PAH)
Mike Simonsen, AAVSO Observer (SXN)
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2. 0324+43 GK PERSEI - Observing Campaign
Astronomers at Livermore National Laboratory in California and NASA
Goddard Space Flight Center are preparing for Target of Opportunity
Observations (TOO) of GK Per - the 1901 nova, classified as a magnetic
cataclysmic variable of intermediate polar subclass - during its next
outburst with the Chandra and XMM X-ray satellites.
GK Per has a quasi-periodic outburst interval ranging from 900 to
1300 days. The most recent outburst of GK Per began in late February,
1999. The star reached a maximum mean magnitude of 10.5 about 1 month
later. Based on the interval between the most recent 2 outbursts
(approximately 1,100 days) we would expect the next outburst to
occur in the next several months. GK Per was featured on the AAVSO web
page as the Variable Star of the Month in November 2000. For more
information please see the following page:
http://www.aavso.org/vstar/vsotm/1100.stm
Also for a brief discussion of the outburst, please visit the URL below :
http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1985PASP...97..
264S
Please keep a very close eye on this variable and inform us when it
starts to brighten -- 12.5 or brighter in magnitude. Immediate
notification of the star's brightening and good coverage throughout
the next outburst are extremely important for the triggering of the
satellite observations and for correlation with the satellite data.
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3. COMMENTS ON LPVs -- J. A, Mattei
Below is a list of some long period variables that need more
observations at this time.
Thanks to the following 27 observers for submitting 164 observations
on the LPVs listed in the November, 2000 issue of Eyepiece Views: AAX,
ABB, BRK, BVE, CRR, DPA, FXJ, GKA, HHU, HZJ, JEA, JM, KHL, LTO, MGH,
MMH, PUJ, RMQ, RSE, SBX, SBH, SFK, SJZ, STI, SVP, TDB, and WSV.
0018-62 S Tuc <9.3-14.5>
This southern variable needs observations at all phases. Its
predicted maximum is for early January. There is an AAVSO 'd' scale
chart for S Tuc.
0202+27 Z Tri 9.4-15.2
One of the interesting features of this long period variable's light
curve is the varying levels of maximum and minimum. The most recent
maximum, in June, was 10.2, a magnitude fainter than in the previous
cycle. The AAVSO 'd' and 'e' scale charts for this star have
eye-estimate comparison star magnitudes. Z Tri needs more observations
and its sequence needs better comparison star magnitudes. Predicted
maximum is the end of January.
0257-51 T Hor <8.2-13.2>
Another southern variable in need of observations at all phases. Its
predicted maximum is early January. There is an AAVSO 'd' chart scale
that has big gaps in the comparison star sequence at the brighter and
fainter ends. Please use this sequence, and do the best you can with
it.
0313+32 TW Per 9.4-(15.0
The light curve of this long period variable suffers from some
observers' using a different sequence than is on the AAVSO 'b', 'd',
and 'e' scale charts. Particularly around maximum, there is a "double"
light curve due to sequence differences. Observers are urged to observe
TW Per using the comparison star magnitudes in the AAVSO sequence, even
if those magnitudes are not optimum, in order to have standardization
of observations. The star is fading from a recent maximum; predicted
minimum is in late February.
0422+15 W Tau <9.9-11.4>
This semiregular variable has not been very periodic in recent
years, making prediction of its maxima and minima very difficult.
Please observe it closely in order to determine its behavior. There is
an AAVSO 'd' scale chart with good sequence; the variable is close to
and northwest of theta1 and theta2 Tau (magnitudes 3.8 and 3.5,
respectively).
0432+74 X Cam <8.1-12.6>
This northern circumpolar long period variable with a rather short
period (144 days) is an easy one to observe. In fact, there are several
bright stars in the area, making it easy to locate, and it is close to
an 8.5-magnitude star just to its northwest. The cycles are never
exactly the same in shape and brightness level of maxima and minima;
some cycles have a bump on the ascending branch. Predicted maximum is
the middle of January. There are good AAVSO 'b' and 'd' scale charts.
0446+17 V Tau <9.2-13.7>
The recent cycle of this long period variable was poorly monitored.
Presently V Tau is brightening to maximum, predicted for the end of
January. It is close to and southeast of the beautiful open cluster NGC
1647. AAVSO 'b' and 'd' scale charts exist. Please use these charts to
make magnitude estimates.
0543-31 S Col <9.3-13.8>
Another southern variable badly in need of more observations at all
phases. Presently it is brightening toward maximum, predicted for the
end of January. The AAVSO 'd' scale chart has big gaps in comparison
star magnitudes at the bright end of the sequence. Do the best you can
to make estimates while the star is brightening. It has been very
difficult in recent years to predict maxima and minima because of the
scarcity of observations.
0557+16 RR Ori 9.4-15.0
The recent cycles of this long period variable have been poorly
monitored. There are AAVSO 'b' and 'd' scale charts with fairly good
comparison star magnitudes. This star is presently brightening towards
maximum, predicted for mid-February.
0728-20B Z Pup <8.1-14.5>
This long period variable with a 509-day period needs observations
as it brightens to maximum at this time. There are AAVSO 'b', 'd', and
'e' scale charts which show a closeby 10.6-magnitude comparison star to
the northeast.
0742-41 W Pup <8.4-12.4>
This Mira variable with a rather short period (120 days) has very
large scatter in the data. The problem may be different comparison star
sequences being used by observers. There is an AAVSO 'd' scale chart.
Observers are urged to use only this chart, in order to have
standardization of the data. Predicted maximum is early January.
0853-00 TU Hya 9.6-(15.5
Thanks to the efforts of our observers, the recent cycle of this
Mira variable was much better monitored than the previous several
cycles. Please continue the good coverage on this star. Maximum is
predicted for early February. There are AAVSO 'b' and 'e' scale charts.
0918-68 RW Car <9.3-15.0>
We are at the mercy of our southern hemisphere observers with this
Mira variable. It is slowly brightening to maximum, predicted for early
February. There is an AAVSO 'd' scale chart. Beware of a 9.7 comparison
star to the east of the variable.
0949-53 Z Vel <9.0-14.3>
Another variable with scatter in the data, particularly on the rising
branch of the light curve. Are observers using different sequences?
There is an AAVSO 'd' scale chart. Observers are urged to use only this
chart, for the homogeneity of the data. This star shows significant
variation in the brightness level of maximum and minimum. It is
presently slowly fading to minimum.
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4. CVs and Unusual Objects for the New Year
By Mike Simonsen SXN
For a constellation with few bright stars, covering only 506 square
degrees, Cancer seems to have a disproportionate amount of cataclysmic
variables and unusual objects.
Fortunately, there are some interesting asterisms and two Messier
clusters to help you star hop around to these variables.
0804+28 YZ Cnc (UGSU) This is one of those hyper active CVs that seems
to be in outburst all the time. Even if you are a weekend warrior you
are liable to catch this one in its active state, and it usually has a
couple bright and long superoutbursts per season. At minimum you may be
able to make positive observations in the 14th magnitude range.
0822+25 AT Cnc (UGZ) Another fairly active CV, this one gets as bright
as 12th magnitude on occasion. Like all Z Cam types, it has
standstills, periods where it gets stuck at one brightness level for a
while before resuming its unpredictable outburst pattern.
0830+21 CC Cnc (UGSU) This star recently underwent a superoutburst in
the 13th magnitude range. Quite faint at minimum, outbursts are few and
far between. This one requires a bit of patience and persistence, but
deserves attention.
0837+28 EG Cnc (UGSU) You may wait a LONG time for this one to go off.
Like WZ Sge, this system rarely goes into superoutburst. The last
outburst was detected by Patrick Schmeer in 1997. It had been a twenty
year wait since the previous outburst. Also like WZ Sge, EG Cnc
exhibits post outburst rebrightenings as it fades from maximum. This is
a very interesting CV to both professionals and amateurs. If you detect
an outburst, notify the AAVSO immediately.
0849+11 AK Cnc (UGSU) Not far from M67, this one is an easy star hop
from #60 Cnc. Outbursts don't come frequently, maybe once a year, but
it can get as bright as 13.2 or so when at maximum. Unfortunately, this
one could use a better sequence and chart.
0849+20 OJ 287 Cnc (QSO) This is an active galactic nucleus. These
variable objects are the powerful centers of galaxies so far away they
appear star-like. The heart of this beast may actually be a binary
black hole system in an elliptical orbit. Ponder that while staring at
this sparse field trying to get a glimpse.
0855+18 SY Cnc (UGZ) Ranging from the mid 10s to mid 13s this is
another delightfully unpredictable CV that can be followed through its
entire cycle with modest telescopes. It also gets stuck in standstills
like AT Cnc and other Z Cam types. The star hop to this one is unique.
I start at FZ Cnc, a 6th magnitude SRB, and follow a question mark
asterism around the horn to get to SY Cnc. Estimating it at maximum can
be a challenge due to a lack of convenient comparison stars in the
bright range.
Cancer is the last best stop heading east in my program. The pickings
get slim in Leo and Virgo. I usually point north to Ursa Major about
here and go around the pole. Ursa Major, now there's a constellation
full of interesting CVs for another time!
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5. 2251-41 SN 2001ig in NGC 7424 (GRUS)
We have been informed by the Central Bureau for Astronomical
Telegrams (IAU Circular 7772) that Robert O. Evans, Hazelbrook, New
South Wales, Australia, visually discovered a supernova in NGC 7424
on DEC 10.43 UT at about magnitude 14.5, using a 0.31-m reflector.
SN 2001ig is located 139" east and 109" north of the nucleus of NGC 7424,
at:
R.A. = 22h 57m 30.69s Decl. = -41degrees 02' 25.9" (2000.0)
An AAVSO 'f' scale preliminary chart of NGC 7424 showing the
location of SN 2001ig has been posted on the AAVSO web page. Please
use this chart (/observing/charts/PRELIM/GRU/SN2001IG_GRU/) to
observe the supernova, and report your observations of 2251-41 SN
2001ig to AAVSO Headquarters, making sure to indicate which
comparison star(s) you used.
This supernova continued to brighten. Your observations of this
supernova are very important so that we may track the recent
brightening. A plea especially to our Southern observers.... Please
continue to keep a close eye on this object.
Here are some recent observations of 2251-41 SN 2001ig
2251-41 SN 2001IG DEC 14.75 2452258.25 14.2 MLF
2251-41 SN 2001IG DEC 15.5619 2452259.062 13.8 PEX K
2251-41 SN 2001IG DEC 15.7799 2452259.28 14.0 MLF
2251-41 SN 2001IG DEC 16.5490 2452260.049 13.5 PEX K
2251-41 SN 2001IG DEC 16.7599 2452260.26 13.8 MLF
2251-41 SN 2001IG DEC 17.2187 2452260.7187 13.5: LMK BS
2251-41 SN 2001IG DEC 17.5400 2452261.04 13.4 PEX K
2251-41 SN 2001IG DEC 18.2173 2452261.7173 13.4 LMK O
2251-41 SN 2001IG DEC 19.2173 2452262.7173 13.1 LMK B
2251-41 SN 2001IG DEC 19.5389 2452263.039 13.0 PEX K
2251-41 SN 2001IG DEC 21.2790 2452264.7791 12.8 LMK BY
2251-41 SN 2001IG DEC 22.2319 2452265.7319 12.8 LMK B
2251-41 SN 2001IG DEC 23.2311 2452266.7312 12.4 LMK BY
2251-41 SN 2001IG DEC 31.7570 2452275.257 12.5 MLF
2251-41 SN 2001IG JAN 05.5131 2452280.0132 12.3 NLX CCD O
2251-41 SN 2001IG JAN 05.7519 2452280.252 12.6 MLF
2251-41 SN 2001IG JAN 06.5400 2452281.04 12.3 PEX K
For more information consult AAVSO News Flashes No. 887 and No. 893 at
the URLs below:
http://www.aavso.org/newsflash/nf887.shtml
http://www.aavso.org/newsflash/nf893.shtml
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6. THE TEAPOT AND THE KITCHEN WINDOW
By Steve O'Connor
Gently I nudged the telescope's tube southwestward towards the
direction of the galactic center. Ah, these calm, comfortable evenings
of early summer were divine for observing. After the frigid darkness of
the past winter, with me in my full seasonal attire featuring four
layers of everything I could find to wear! Looking like a dime store
moonwalker and gazing up through minus 20 degree air at GEM was no
party! However I was certainly making up for it now, I mused, counting
only a pair of shorts and a wrist watch as this evening's observing
garb. As I steered my 8" Newtonian ever so slightly southward I suddenly
paused as the impressive ruddy hue of KW SGR signaled the end of my
current starhop. Over the past couple of years I had become increasingly
impressed with the number and variety of unusual variable stars in this
part of the sky. And even though SGR never rises very far above the
rooftops here in metropolitan Montreal, its' abundance of variables and
the fact that for many of our observers in mid-northern latitudes, SGR
is not conveniently accessible for one reason or another have combined
to make this constellation quite irresistable to me!
As I was estimating my variable, the glare of automobile headlights
turning into the driveway ushered me back to Earth for a
moment.......... a police patrol car even! Unusual, I thought. Looked
like I was about to receive a visit by two of our city's finest! I laid
my chart on the tiny table beside me, weighing it down with my reddened
flashlight, then paused to greet my two rather large, unannounced guests
who were by now on their way to the backend of the driveway where I,
straightening my wristwatch, prepared to welcome them. "Good evening
sir" the taller of the two spoke as they walked up to where I waited.
"And a very good evening to both of you" I returned, as I watched the
quick but thorough visual inspection my reflector, charts, and
accessories received from the speaker's partner. "How's everything
tonight ?" the officer queried. "Excellent", I returned. "I'm just now
observing a red supergiant near the Teapot", I added. "Variable stars",
I offered, "KW SGR to be exact", realizing that by now, my motorless
telescope would have lost the star and that another hop would be
required before I would be able to get my estimate. The policemen
grinned at each other, switching off their flashlights. "Here, let me
find you something special to see", as I popped in my wide-field ocular
and guided the 'scope to M22. "Have a look", I motioned them closer.
Both men took a turn peering into the 8" at the fuzzy target so many
thousands of light years away. After supplying an explanation to clarify
for them what they were actually looking at, they again eyeballed one
another and then turned to me, the larger of the two saying "Thank you
very much sir for your time. There seems to have been a little
misunderstanding on the part of one of your neighbors one street over,
whose backyard faces your driveway. Seems like the lady thought you may
have been spying on her through her kitchen window!" We all turned at
once in the direction the telescope was pointed, and sure enough, just a
couple of degrees below the Teapot ..... a lighted kitchen window
replete with several hanging plants stared back at us! "Oh boy!", I
exclaimed, "Oh no, officers!, Please rest assured that I'm making
variable star observations for the A.A.V.S.O.!" My guests, seemingly
satisfied with my scientific commitment, bid me a good evening and
turned back towards the patrol car. " 'Night officers" I said, "Have a
good shift". I swung around to look at my blessed Teapot once more. And
then the kitchen window, grinning to myself and gently shaking my head
as I got back to work.
To this day, SGR continues to be my favorite observing ground. Also to this
day, whenever I'm near the Teapot, actually any teapot!, I think of that
memorable evening, years ago, and smile to myself once again.
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7. HOAFUN 2 FOR WINDOWS
HOAFUN 2 has been released at the URL below via the AAVSO web site:
http://www.aavso.org/adata/hoafun.shtml
HOAFUN was originally a MS-DOS based program distributed with the
Hands-On Astrophysics package. This new version is designed for
Windows and has a point-and-click interface along with a few new
features.
The goal of HOAFUN is to teach the basics involved with making a
variable star observation. It includes step-by-step tutorials and
animations involving the most popular classes of variable stars. It
also has a game with different levels of difficulty. When the game is
over you can even print out a certificate with your score on it.
HOAFUN is designed for junior high through college aged students,
but is very useful for anyone just starting out with variable stars.
As always, the download is free.
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8. VARIABLE STARS OF THE MONTH FOR 2001
Over the past year, 12 stars have had the honor of being named the
"Variable Star of the Month" (VSOTM) on the AAVSO web site. Since its
inception in November of 1998 the VSOTM has become one of the most
popular sections of the site. Stars are chosen based on criteria such as
accessibility at that time of year, popularity among observers,
historical and scientific significance, and more.
Below is a list of VSOTM's for 2001.
January: BL Lacertae
February: T Tauri
March: Supernova 1987A
April: R Leonis
May: Novae (in general)
June: AM Hercules
July: EU Delphini
August: RY Sagittarri
September: WZ Sagittae (variable star of the year?)
October: Gamma Cassiopeiae
November: R Cygni
December: IP Pegasi
You can access the archive at the URL below:
http://www.aavso.org/vstar/vsotm/archive.stm
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9. The AAVSO Variable Star Chart Program 6-Month Plan: Easy-Use Policy
2002 will be a year of great activity in terms of AAVSO variable
star charts. We have ambitious plans to improve every aspect of
variable star chart creation, distribution, and use. Below is a
summary of the ideas and plans we currently hope to implement next
year.
We have setup a new e-mail box at HQ dedicated to communication
about charts. The address is simply charts@aavso.org. Send any ideas,
requests, or concerns to that address.
"Easy-Use Policy": A Proposed New Method for Submission of Chart
Information
For a while now chart information has been a required part of the
Official AAVSO Format (http://www.aavso.org/cdata/official.stm).
However, we have not been enforcing this requirement because we
realized it would create a huge burden to some observers.
Sometime next year we hope to begin a policy of requesting that
chart data be included in your observation only the *FIRST TIME* that
you use a chart. Every other observation you make with that chart
_does not_ need to include chart data.
For example, let's say Jane downloads a new chart for SS CYG. In her
first observation using that chart she will fill out the chart field.
But in the future, she can leave that field blank as long as she uses
the same chart!
Details of this new policy will be published on the AAVSO WWW site,
discussion group, Eyepiece Views, in the next newsletter, and other
places. Please note that we are not asking you to include any new
data in your report. In fact, this should make your reports shorter
and easier to submit, hence why we are calling it the "Easy-Use
Policy".
AAVSO Variable Star Chart CDROM 2.0
A second version of the successful AAVSO Variable Star Chart CDROM
will be published in 2002. This new version will likely be a
two-cdrom set with the following features:
- Over 100 new eclipsing binary charts
- Over 50 new RR Lyrae charts
- Over 30 new PEP charts
- Hundreds of new and updated visual and CCD charts
- ChartCD: The AAVSO Chart Collection CDROM Software (see below)
Merging of Standard & Preliminary Catalogs
The AAVSO Standard & Preliminary chart catalogs are going to be
merged into one large catalog. This basically means that we are
eliminating the distinction between a "standard" and a "preliminary"
chart. This was important for accessing charts in the past but not
anymore.
a distinction used for internal
purposes in the past and isn't needed anymore. This doesn't affect
most observers and is more of an administrative change.
ChartCD: The AAVSO Chart Collection CDROM Software
Near the beginning of the new year "ChartCD" will be released on
the AAVSO WWW site. It is currently in beta testing by a handful of
volunteers. It is a Windows program that works with the current chart
CDROM being distributed (1.0). Some of the things the program will do
is:
- Print charts on a single sheet of paper
- Search the chart catalogs for stars based on RA, DEC, scale,
and more.
The ultimate goal for this program is for it to be an observation
planning tool. It should implement all the search functions we have
in our online chart search engine
(/observing/charts/)
such as searching the chart catalog for objects based on RA, DEC,
chart scale, magnitude range, star type, constellation, and any
combination thereof.
International Cooperation
At the end of the 90th Annual Meeting of the AAVSO last November a
second small meeting was held with a few of the international chart
makers. At the Pan Pacific AAVSO Spring Meeting in Hawaii this July
we hope to have another chart meeting with even more of our
international colleagues joining us. So far progress has been
excellent and we look forward to even more cooperation.
Future
All of these plans and ideas have one goal in mind: to increase the
accuracy and speed in which we publish variable star charts. We are
moving into the future and staying up to date with the current trends
in astronomy.
Conclusion
Please stay tuned to your favorite publication (Newsletter, WWW
Site, Eyepiece Views, CCD Views, Discussion Group, etc.) for news on
these projects as each comes to fruition. If you have any ideas feel
free to send them to charts@aavso.org. Thanks and good observing!
Janet Mattei
Aaron Price
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EYEPIECE Views is published bimonthly and when circumstances warrant
via e-mail. An archive is available at http://www.aavso.org/eyepieceviews/ .
Please send comments and suggestions to gamze@aavso.org.
To receive EYEPIECE Views via e-mail send a message to
majordomo@aavso.org with "subscribe eyepieceviews" in the body of the
e-mail. To unsubscribe, place "unsubscribe eyepieceviews" in the e-mail.
The AAVSO has many free online publications including "CCD
Views", a similar newsletter intended for ccd observers. To learn
more and subscribe visit: http://www.aavso.org/mailinglists.stm
Good observing!
Gamze Menali,AAVSO Technical Assistant (MGQ)
Aaron Price, AAVSO Technical Assistant (PAH)
Mike Simonsen, AAVSO Observer (SXN)
Copyright 2001, American Association of Variable Star Observers
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THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
25 Birch Street, Cambridge, MA 02138 USA
Tel. 617-354-0484 Fax 617-354-0665
http://www.aavso.org
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