May 16, 2010 VENUS OCCULTATION
OBSERVATION REPORT
by James
Kevin Ty
Johndel Beach Resort , Nasugbu , Batangas
Last May 16, 2010, ALP
President James Kevin Ty together with fellow ALPers
Andrew Ian Chan and Babak Parhizkari went to Nasugbu ,
Batangas to document the Venus Occultation by the Thin
Crescent Moon. Aside from Nasugbu, ALP also have 2 more
observing stations which were in Astrocamp Observatory
in SM Mall of Asia as well as in Candaba , Pampanga.
James decided to lead the Nasugbu team so that ALP
will have alternative sites as well as get better
chances to observe this event successfully instead
of just one observing site. Also, the reason to pursue
the Nasugbu site is because of the low latitude
reappearance of Venus from the bright limb of the Moon
which was a bit low at 3 degrees in Manila.
In Nasugbu, the reappearance is also very low at 2
degrees above horizon. The good advantage here is that
Venus and Moon will set at the sea line instead of
mountains and the plus factor here is that we were able
to get an additional 2 minutes more before Venus exits
the bright lunar limb. Venus exits at 8:18pm Manila Time
compare to Manila's 8:16pm.
Anyway, they depart Manila at around 11:00am and arrive
in Tagaytay at around 1:00pm. They then had lunch at
Terriyaki Boy before proceeding to Nasugbu, Batangas.
They arrived in Nasugbu at around 2:45pm and stayed at
Johndel Beach Resort which James had several
occultation observing events there before whenever
the need of a clear out western horizon.
They checked in at the 3rd floor so that they will have
easier time to transport their imaging equipment to the
roof deck with convenience later. Inside the room, their
astro imaging equipment lay scattered out all over the
floor and beds to ensure all items needed area are
intact accounted for.
At around 5:30pm, they started
to setup their equipment and try to image the elusive
green flash but unfortunately, tough luck for them as no
green flash was visible when the Sun got flattened
out in the sea horizon :( Anyway, better luck next time
. For this event, James brought along his trusty
TV-101 refractor and GP-DX mount. He also installed a
Digital 8 video camera so that he can document both in
still and video mode. Andrew, on the other hand brought
along his Skywatcher 80ED refractor on his new GP mount
equipped with Sky Sensor 2000-PC. Babak brought his WO
Z70 ED refractor as well as Skywatcher 102mm
Maksutov-Cassegrain telescope which he will install on
his highly portable Takahashi Sky Patrol 2 mount.
Initially, James plan to use his Kenko Sky Memo for this
event, but since he still doesn't have a lighter ED
refractor such Megrez 72FD or the one he like most, Canon EF 100-400mm F/4.5-5.6 IS L lens.
He decided not to bring it and use his old previous mount system instead.
While the Sun is setting, Babak called our attention and
pointed to planet Venus which was several degrees above
the 2.5 day old thin crescent Moon! It was a very
beautiful sight to behold as Venus got closer and closer
to the dark limb of the Moon! They started to check
their exposures to get a good balance exposure of the Moon
with Earthshine as well as Venus without over exposing
too much to make the planet Venus become a blob of
light.
At around 7:30pm, they started to monitor Venus as it
gets closer and closer to the dark limb of the Moon. At
the same time, a lot of James' friends and
colleague started to call his mobile to ask what the bright star that is above
the Moon. He told them it was planet Venus and they were
quite surprised and excited when he told them the planet
Venus will disappear suddenly at around 7:36pm :) For
their area
in Nasugbu, estimated time of Venus disappearance
(Ingress) will be at 7:36pm and exits behind the bright
limb of the Moon at around 8:18pm. True enough, Venus
disappeared exactly at 7:36pm and reappeared at 8:18pm!
They synchronize theirr watch and camera clock with
James' GPS unit. It also provided them their
current location at 14.0716 North and 120.6254 East.
Their final contact timing time of
Ingress was 7:36:07pm and Egress at 8:18:11pm.
After the event, Babak and Andrew tried testing their
new mounts on starts and DSOs to check tracking
accuracy. Before they packed up, they had their
traditional group shot taken and when they arrived back to
their airconditioned room, they cool down their body
then took a good shower and started to load their stuffs
back to the car. Since the restaurant was already closed
at 10:30pm, they had a very late dinner at Jollibee Tagaytay before
going back to Manila.
James beside his trusty TV-101
refractor on Vixen GP-DX mount with Digital 8 video
camera. |
Andrew beside his Skywatcher
80ED refractor on Vixen GP mount. |
Babak beside his Canon 5D Mark
2 with EF100mm 2.8 lens on Takahashi Sky Patrol 2
mount. |
ALP VENUS OCCULTATION NASUGBU
TEAM |
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