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THE TRANSIT OF VENUS IN NEW YORK
 ------------------------------
 John Pazmino
 NYSkies Astronomy Inc
 www.nyskies.org
 nyskies@nyskies.org
 2012 April 29 initial
 2012 Jun 1 current
Introduction
 ---------- 
    This article discusses the Venus transit of 2012 June 5 from New 
    York City and surrounds. It gives the significant information to 
organize your observing but skips most of the historical and technical 
aspects of the event. The transit is already a substantial portion of 
litterature, in print and online. Much is an accumulation onto the 
material issued for the 2004 transit. 
    There is no similar page here for the 2004 transit because it 
preceded the NYSkies website. Information about that transit was 
disseminated to City astronomers thru the NYSkies yahoogroup and 
takeaways at various astronomy meetings around the City. 
    Many facts & figures here are adapted from other astronomy sources 
while others come from my calculations or simulations via computer 
astronomy programs. Much of the advice here is similar to that for 
viewing the Stonehenge sunset on Manhattan. The transit and Stonehenge 
occur a few days apart under about the same regime of weather and 
summer conditions. 
June 5th or 6th? 
 -------------- 
    Understand well that in New York, and all of the Western 
Hemisphere, the transit occurs on June 5th and NOT on the 6th. This is 
due to two causes. The first is that the middle of transit, for which 
the time of occurrence is typicly cited, does fall on the 6th. The 
event spans about six hours, from the late hours of June 5th and early 
hours of June 6th n Universal Time. The start of the transit is at 
about 22:05 UT on June 5th 
    The other reason is a timezone shift. New York time is four hours 
behind Universal Time. That is four, and not five, due to Daylight 
Savings Time prevailing during the transit. The beginning of the 
transit in New York is near 18:05 on June 5th. 
    This table shows the times of the transit in UT and EDST. UT is 
also known as GMT. All hours here are geocentric.
    ------------------------------------------
    location  | zone | contact I | middle    | contact IV
    ----------+------+-----------+-----------+-----------
    Greenwich |  UT  | 22:09 5th | 01:29 6th | 04:49 6th
    New York  | EDST | 18:09 5th | 21:29 5th | 00:49 6th
    ----------------------------------------------------
   The confusing region of the world is the Pacific Ocean, where the 
transit if visible from start to end in midday. The hours span the 
International Date Line. Observers west of IDL see it on June 6th and 
those east of IDL see it on June 5th! 
Viewing site
 ----------
    There is no special location in and around the City to view the 
transit. Like for a lunar eclipse, any place that offers a clear line 
of sight to the Sun is quite good enough. Because the transit 
continues thru sunset, the prime factor to look for is a low 
northwestern horizon around the summer sunset point. 
    A high skyline will shorten the duration and extent of the event, 
which continues out of sight behind such obstructions. Elevation to 
look over foreground skyline; waterfront looking over large waters are 
the two principal types of viewing site for a view of Venus.on the 
solar disc. 
    The transit takes place on a weekday afternoon. Essentially all 
places with public access will be open anyway with no need for special 
permission. As long as the group with you is small, casual, and well-
behaved there'll be no trouble setting up in a public place to view 
the transit. 
    If you intend to invite many people, like friends, to a private 
property, please obtain beforehand proper permission from the property 
manager. This will prevent nasty interventions by the manager during 
the viewing. Usually all that's necessary is a due & proper notice to 
the manager that so-many visitors are expected on such-&-such day and 
time for a few hours, like for an afternoon social. 
    The one sticky factor could be your proximity to a sensitive 
facility that doesn't like spying. Your astronomy gear could be taken 
as part of suspicious action against the facility, like a monitoring 
or targeting apparatus, You may have to show to the police what's 
what. Have with you Venus transit litterature for the police. 
Public viewing sessions
 ---------------------
    In late May 2012 astronomy groups thruout the zone of visibility 
of the transit are planning public viewing sessions. These are typicly 
gatherings in open fields or yards where local astronomers have 
properly protected telescopes to let visitors see Venus on the Sun. 
    Please know that only such sessions are we are advised of can be 
enrolled here. A session away from our attention will be missed. 
    Like for any celestial viewing the transit is observable only in 
clear sky, with some tolerance for thin cloud and haze. Clouds thick 
enough to erase shadows, rain, strong wind, service disruptions, among 
other causes, can call off a scheduled session. 
    Follow the advice of the sponsor. This is given when inquiring 
about the session or in litterature sent to you, like by email. In 
general, dress for the prevailing weather plus reasonably anticipated 
adverse weather, 
    ==========================================
    Sessions start at 17:00 unless stated otherwise. Info is correct 
    as at 2012 May 29. Viewing is cancelled for clouds unless stated 
    otherwise. The viewing site is NOT always the same as the club's 
    normal meeting site. OBTAIN LATEST NEWS DIRECTA MENTE FROM THE 
    CONTACT BEFORE HEADING OFF TO THE EVENT!! Skipping this crucial 
    step could cause devastating ruination of our Venus transit 
    experience. 
    ========
    CONNECTICUT 
    -----------
    Danbury CT. Westn CT St Univ, Midtown Campus, Sci Bldg roof. Free. 
    www.wcsu.edu/starwatch
    -----
    Greenwich CT. Curtis Elem Schl, Bowman Obsy. Astro Soc of 
    Greenwich. Free. rickbria@optonline.net, www.seocom.cgfom/asg, 
    -----
    Stamford CT. Stamford Musm, Plm. $3 adm. Indoor show, telecast of 
    transit, talk. Clearsky outdoor viewing. cescovil@earthlink.net 
    www.stamfordmuseum.org 
    -----
    Westport CT. Rolnick Obsy. Westprot Astro Soc. Free. 
    www.was-ct.org
    ===== 
    LONG ISLAND 
    -----------
    Jones Bh LI. Roosevelt Natr Ctr. Amat Obsrs Soc. 17:30 in-house 
    observing, 18:30 public viewing. $4 adm, adv regn reqd. For 
    clouds, relocate to Sunken Meadow St Pk, else cancelled.
    Stargazing after sunset requires previously obtained permit. 
    suerose@optonline.net, www.aosny.org 
    ===== 
    MANHATTAN 
    ---------
    Amer Musm Natl Hist, Rose Ctr, 81 St entrance. $12 musm adm. 
    Indoor show, telescast of transit, no outdoor viewing. 
    www.amnh.org 
    -----
    Harlem Central, Powell Bv (7 Av) & 125 St. Columbia Univ Obsy.
    Free. outreach.astro.columbia.edu
    -----
    Intrepid Musm, Pier 86. Intrepid Musm & NYSkies Astro Inc. $5 adm 
    to pier, ship is closed for Enterprise prepaaration. Rain shelters 
    on pier. Personal starviewng after sunset on adjacent pier 84. 
    www.intrepidmuseum.org, algenib56@yahoo.com, nyskies@nyskies.org
    -----
    Riverside South Park, 70 St entrance. Amat Astro Assn. Free.  
    Supper break after sunset, then return for starviewing. 
    president@aaa.org, www.aaa.org. 
    -----
    The High Line, 14 St entrance. Amat Astro Assn. Free. Supper break 
    after sunset, then return for starviewing. president@aaa.org, 
    www.aaa.org. 
    -----
    Union Square, 14 St & Broadway. CoLUMBIA uNIV oBSY.fREE.
    outreach.astro.columbia.edu/
    ===== 
    NEW JERSEY 
    ----------
    Beachwood NJ, Jakes Br Cnty Pk. Astro Soc of Toms River Area. 
    Free. www.astra-nj.org, webmaster@astra-nj.org 
    -----
    Booton NJ, NJ Rte 80, Exit 19, eastbd overlook. Sheep Hill 
    Astro Assn. Free. www.sheephillastro.org, wwestura@optonline.net, 
    contacts@sheephillastro.org 
    -----
    Morristown NJ, Morris Musm. Morris Musm Astro Soc. Free. 
    ckkrish@gmail.com, info@morrismuseum.org, www.morrismusem.org 
    -----
    LebanOn NJ, Teetertown Ravine. NJ AStro Assn. Free. www.njaa.org 
    -----
    Livingston NJ, Riker Hill Art Pk. Newark Musm & No Jersey Astro 
    Gp. Free. planetarium@newarkmuseum.org, www.newarkmuseum.org 
    -----
    Princeton NJ, Princeton Univ, Peyton Hall, Amat Astro Assn of 
    Princeton. 16:00. Free. Indoor show, then outdoor viewing at 
    Engineering Quad parking deck. Return to Payton Hall for telecast 
    of rest of trasnit. For clouds, entire show is at Peyton Hall. 
    info@princetonastronomy.org, www.princetonastronomy.org 
    -----
    Sandy Hook NJ, western tip of peninsula. Amat Astro Inc. Free. 
    www.asterism.org, hfjacinto6@gmail.com 
    ===== 
    QUEENS
    ------
    York College, 160 St & Archer/Lberty Av. Free. View by projection. 
    www.york.cuny.edu/centers-institutes/observatory, 
    tpaglione@york.cuny.edu, 
    ===== 
    STATEN ISLAND 
    -------------
    College of SI. Astrop Obsy. Free. Whitelight & H-alpha viewing. 
    profirobbins@aol.com, robbins@mail.csi.cuny.edu, 
    supernova7.apsc.csi.cuny.edu 
    ===== 
    UPSTATE 
    -------
    New Paltz NY. SUNY New Paltz, Lecture Ctr. Mid-Hudson Astro Assn & 
    SUNY New Paltz. Free. Indoor talk, then oudoor viewing at 
    Coykendall Sci Ctr. For clouds, telecast of transit. 
    www.midhudsonastro.org, president@midhudsonastro.org,
    maureendford@gmail.com 
    -----
    Sleepy Hollow NY, Phelps Meml Hosptl Ctr, James House. Westchester 
    Anat Astro. Free. www.westchesterastronomers.org, 
    waa-president@westchesterastronomers.org 
    =====
Travel for viewing 
 ----------------
    It is not necessary to leave new York to see the transit, unlike 
for a total solar eclipse. Unless you have convenience to be else 
where, the view from the City is really a good one. 
    The farther west in the United States you are located, the longer 
the view and greater the extent is because the transit begins earlier 
on the clock in the local timezone. Sunset is more or less the same, 
depending on latitude, at 20:20 in local daylight time. 
    Your astronomy gear could be inspected at airports, with potential 
for confiscation! Have with you at ready litterature about the transit 
to show the security agents. Offer to have certain items packed for 
checked baggage if there's concern about having it with you in the 
cabin, Be prepared to repack your baggage by modularizing your gear. 
Stages of the transit 
 -------------------
    The progress of venus across the Sun is marked by several stages, 
or contacts. The transit begins when the disc of Venus first touches 
that of Sun, they being tangential on their external edges. This is 
first contact or contact I.
    For whitelight solar observing, typical for viewing with front-end 
solar filters or projection, this contact is not actually seen. 
Instantly you see the tiny notch of Sun eaten out by Venus, first 
contact is already passed. 
    When the discs are tangent on their internal edges, venus is just 
completely onto the Sun. This is second contact or contact II. venus 
marches across the Sun to the far side and hits contact II and IV to 
leave the Sun's disc. For New York the Sun sets long before these 
contacts.
    The middle of the transit is when Venus is halfway along her track 
across the Sun or when she is closest to the center of the solar disc, 
with minimum separation from it. This stage is not obvious, but can be 
deduced by measuring from photographs. It is not all that important 
because it's the contact times that fix the end points of the track 
across the Sun. 
    The transit begins in New York at 18:03 EDST. Venus procedes into 
the Sun's disc and is about 1/3 way along her path when the Sun sets. 
We do not get the midpoint of the transit yet still are treated to a 
2-1/2 hour show. This is the order of a lunar or partial solar 
eclipse. 
Local circumstances 
 -----------------
    Since the City was founded we experienced seven Venus transits as 
at 2011 with three more in the next hundred and so years. The extent 
of the transit visible from the City cover all possibilities. 
    ------------------------------
    extent                |  years 
    ----------------------+-------
    none visible           | 1631  1761  1874  2117 
    in progress at sunrise | 2004 
    in progress at sunset  | 1639  1769  2012 
    fully visible          | 1882  2025 
    -----------------------------------
    The table below gives specs for all ten transits. The first row 
gives the date, the UT hour for each contact, minimum separation of 
Sun and Venus in arcseconds, and Sun's right ascension and 
declination. 
    The date, like for the 2012 event, is that prevailing at the 
midpoint of the transit. See that the first and second contacts occur 
before midnight; third and fourth, after midnight. 
    The second row gives the Greenwich Sidereal TIme at 0h UT for the 
date, altitude of the Sun for each contact, and notes about the extent 
of transit visible from the City. 
 ------------------------------------------------------------------
 Local Circumstances for Transits of Venus: 1631-2125 from New York 
 City. Geographic position: Latitude: N40.717, Longitude: W74.017                       
 ---------------------------------------------------------------------
 Date            I      II    mid     III    IV   Sep"   SunRA  SunDE 
 -----------   -----  -----  -----  -----  -----  -----  ------ ------  
 1631 Dec 07   03:52  04:59  05:19  05:40  06:47  939.3  16.912 -22.64   
    5.045        -68d   -72d   -71d   -69d   -59d none visible 
 1639 Dec 04   14:57  15:15  18:26  21:36  21:55  523.6  16.738 -22.34   
    4.888         22d    23d    23d    -2d    -5d I, II, mid visible 
    121-1/2 years 
 1761 Jun 06   02:02  02:20  05:19  08:18  08:37  570.4   4.957  22.69  
   16.988        -15d   -17d   -26d   -11d    -8d none visible 
 1769 Jun 03   19:15  19:34  22:25  01:16  01:35  609.3   4.805  22.44  
   16.842         55d    52d    20d    -9d   -12d I, II, mid visible 
      105-1/2 years 
 1874 Dec 09   01:49  02:19  04:07  05:56  06:26  829.9  17.056 -22.82   
    5.182        -48d   -54d   -70d   -67d   -63d none visible 
 1882 Dec 06   13:57  14:17  17:06  19:55  20:15  637.3  16.881 -22.56   
    5.025         15d    18d    27d    13d    10d all visible 
      121-1/2 years 
 2004 Jun 08   05:13  05:33  08:20  11:07  11:26  626.9   5.121  22.89  
   17.137        -26d   -26d   -11d    17d    20d III, IV visible 
 2012 Jun 06   22:03* 22:21* 01:30  04:32  04:49  554.4   4.969  22.68  
   16.991         24d    21d   -11d   -26d   -27d I, II visible 
      105-1/2 years 
 2117 Dec 11   23:58  00:21  02:48  05:15  05:38  723.6  17.201 -22.97   
    5.320        -27d   -32d   -59d   -71d   -69d none visible 
 2125 Dec 08   13:15  13:38  16:01  18:24  18:48  736.4  17.026 -22.74   
    5.163         10d    13d    26d    23d    21d all visible 
 * Topographic times. All others in this table are geocentric. 
 ------------------------------------------------------------
    I grouped the transits in their 8-year pairs. The pairs are spaced 
over a 100 years apart. I note the approximate interval between the 
pairs. 
    This means that any living person may witness at most two 
transits, those of the pair occurring in his lifetime. Not every one 
will be so lucky. With current, extended, lifespans, you could live 
entirely between transit pairs and never witness the show. 
    The transit times in this table are geocentric EXCEPT for the two 
starred times in the 2012 event. These are the topocentric times for 
the geographic location of New York, are closer to the observed time. 
    For the others, geocentric, ones the observed times may differ by 
up to 10 minutes. Further more, the Sun's actual altitude may differ 
by up to 2 degrees from this table due to the geocentric approximation 
and atmospheric refraction. 
Nearby towns 
 ----------
    I give here the specs for a few nearby towns to allow some 
interpolation for sites a little ways beyond New York. Like for solar 
and lunar eclipses and lunar occultations, you are ready a few minutes 
ahead of time. 
 -------------------------------------------
 Location          1st contact   2nd contact 
 ----------------  -----------   -----------                              
 name              EDST      alt  EDST      alt 
 ----              --------  ---  --------  ---
 Albany, NY        18:03:45  24   18:21:24  21 
 Hartford, CT      18:03:43  23   18:21:22  20 
 New York, NY      18:03:47  24   18:21:26  21 
 Philadelphia, PA  18:03:50  25   18:21:30  21 
 --------------------------------------------- 
Path in the sky 
 -------------
    For New York and generally thruout the NYSkies turf the transit 
begins, first contact, when the Sun is in altitude 24 deg, azimuth 280 
deg. He travels in sensibly a straight line diagonal to the lower 
right to set in azimuth 301 deg. Azimuths are geographic, not 
Manhattan grid. 
    A viewing site suitable for the Stonehenge sunset may be good for 
the transit if it offers also a sightline over this path of the Sun. 
One restricted to the gorge between towers along a street will not 
such a suitable site.
    The table here gives the altitude and azimuth of the Sun for New 
York City to help select an observing site. It is substantially the 
same thruout the NYSkies region.
    -----------------------------------------
      EDST  | event       | Sun al-az | remarks 
      ------+-------------+-----+------+--------
      18:03 | 1st contact | 24d, 280d | Venus hits Sun, 12:30 on limb 
      18:21 | 2nd contact | 20d, 285d | Venus fully on Sun disc  
      20:25 | sunset      |  0d, 301d | Venus 1/3 across Sun disc 
      20:57 | civil twilt |    --     | end of daylight activity 
      21:40 | nautl twilt |    --     | full night in New York 
      --------------------------------------------------------
    The moment of sunset wanders a couple minutes among references due
to the method of calculation and the allowance for air refraction.
Venus on the Sun 
 --------------
    The transit is like an eclipse where the covering body is way too 
small to fully hide the Sun. Venus when in front of the Sun is quite 1 
arcminute diameter against the Sun's average 31 arcminutes. The dot of 
Venus is tiny, just barely within discernibility by good eyesight with 
suitable protection. Some people will spot this dot. Others miss it. 
    Any binoculars or spotting scope will clearly distinguish Venus 
from a sunspot and allow you to follow her progress across the Sun. 
Venus is a black perfectly round dot that obviously moves over the Sun 
within several minutes. Sunspots are irregular shaded patches that 
stay put on the solar disc during the transit. . 
    Venus enters the Sun quite at his upper limb, near the 12 o'clock 
point around his disc. Venus travels diagonally to the lower right 
toward the 4 o'clock point. She doesn't reaches even halfway there 
before the Sun sets. 
Sun-Venus size 
 ------------
    Seeing Venus, and also Mercury, marching across the SUn vividly 
compares the linear size of a planet against the globe of the Sun. 
Most pictures in astronomy boos and articles, even those meant for 
instructing in the science, make the planets grossly too big, large 
fractions of the Sun's size. In fact, from a remote viewpoint, it 
would be real tough to tell that there is anything circling the 
Sun.When detected, the planets seem like mere specks. 
    The largest of the planets, Jupiter, is just about 1/10 the 
diameter of the Sun (but barely 1/a000 his mass!) and Earth is about 
1/100 that diameter. Venus, being a little smaller than Earth, is 
alson about 1/100 the solar diameter. 
    As a side-by-side comparison during the transit, Venus is actually 
    TOO BIG against the Sun! Venus is about 1/3 as far from us as the 
Sun 
and appears about 3 times larger than if she was adjacent to the Sun. 
Even with the too-large venus, you see just how humongous the Sun is 
against a planet. 
 
Venus atmosphere 
 -------------
    While viewing the Sun at the ingress of Venus you MAY witness an 
incredible feature. Sunlight COULD be spread around the edge of the 
venus disc thru her own atmosphere, making a subtile outline off the 
edge of the Sun. 
    This was seen by some -- but not all! -- observers at the 2004 
transit from new York. At that time venus was leaving the Sun, having 
been already in march on the Sun at sunrise. 
    An other effect happens just when venus is fully on the Sun, at 
second contact. She pulls with her a thread of black 'mucus' like 
thick ink, that finally snaps loose to leave clear Sun all around  
Venus. This is the 'black drop' effect, also witnessed by some -- but 
not all! -- observers in 2004 from the City. 
    Altho the cause is still unsettled the black drop ws captured from 
spaceprobes examining transits of Mercury in reent years. Such views 
rule out a terrestrial origin in the air. There could still be some 
instrumental cause in the way sensing devices, including the human 
eye, rcords the contact between Venus and Sun. 
    These two effects are seen, assuming the usual viewing methods, 
only thru a filtered telescope that makes a comfortably large Venus 
image. They are not discernible in low power or binoculars. 
Weather 
 -----
    The transit of Venus on 2012 June 5 is only a few days after the 
first of New York's two Stonehenge periods. The situation for viewing 
both events is about the same. 
    The Venus transit takes place in the New York summer hot & humid 
season. You could be waiting for the sunset under oppressing 
uncomfortable conditions. In such combination of temperature and 
humidity, the body can not transpire properly, leading to sweatiness, 
drowsiness, internal loss of water. 
    Wear light loose clothes, have a bottle of fresh water. Walk and 
climb stairs slowly, don't run or jog. If feasible, view at a site 
with nearby shade like trees or walls. Bring a folding stool or chair 
to rest on. A battery -- or solar! -- powered fan can be very 
refreshing. 
    One horrible threat against comfortable transit viewing is the 
late afternoon thunderstorm. You could be trapped in one because 
you'll be under the open air for several hours watching Venus creep 
over the Sun.
    In New York commonly on the summer days a tumultuous storm erupts 
in the mid to late afternoon, throwing many centimeters of rain with 
blinding lightning and crashing thunder. 
    The typical storm lasts only a half hour, but hour-long deluges 
are annoyingly frequent. On the whole, regardless of the start and 
duration, the storm abates before sunset. 
    This behavior of a common summer storm can knock out much of the 
viewing period for the transit. There's nothing to do but take to 
shelter and wait it out. It is prudent to have totable equipment which 
can be scooped up and carried to safety, Else have at ready tarps to 
cover heavier bulky gear. 
    You could be soaked thru and thru, taking on a nasty disheveled 
feeling. The ground and street furniture may still be wet. Grassy 
sites may still be soft and squishy under the foot. 
    In the event of the afternoon thunderstorm, arm yourself with 
newspaper to lay on wet furniture, be willing to take splashes and 
drips.
Rainbows? 
 -------
   While the Sun is setting in the northwest, the antisolar point is 
rising in the southeast. If there was a rain moving eastward after it 
stops over you, there is the chance to spot a rainbow. 
    On the whole, storms sweep over the City from west to east, When 
the sky is clearing in the west near sunset, rain could still be 
falling in the opposite direction. This makes a wall of raindrops 
catching the rays of the setting Sun to generate rainbows. 
    There's plenty of slack time to turn around and look away from the 
Sun and look for a rainbow. The shadow of your head is the center of 
the rainbow. 
    Because of a rainbow's large diameter, about 45 degrees, you 
should ideally be at a site with an open view to the east and 
southeast. With a street hemmed in by towers, you may see only the 
upper segment of the bow centered over the street. 
    Nothing is promised, even if there was a rain that by sunset is 
retreating into the east. The rain may have ended, moved out of 
alignment with the Sun, or shrunk too small to make rainbows. 
    You could get a double or multiple bow! The extra ones are outside 
of, and concentric with, the main bow. 
    Photographing a rainbow is a bit tricky. Metering off of the sky 
itself can produce an overexposed picture. The rainbow is diluted with 
weak color. Meter off of the foreground scenery, lock the setting, and 
shoot with it at the bows. 
Clouds
 ----
    The transit is more like a lunar eclipse, a leisurely show lasting 
many hours. A passing cloud only momentarily interrupts your viewing. 
You may still observe the transit thru the thinner parts of clouds but 
the thicker parts may dim the Sun too deeply. 
    Haze and certain clouds may diffuse the image, turning Venus into 
a soft fuzzzball. You'll recognize her by the perfectly round shape 
and steady motion across the Sun. On the other hand a diffuse Venus 
will weaken the effect of her ingress onto the Sun.                   
    Never remove your solar filter to watch with only a cloud to 
attenuate the solar rays! This is a most dangerous tactic! Leave the 
filter in place and wait for the cloud to thin out or move away. 
Bare-eye view 
 -----------
    For the transit there is no cause to inspect the Sun by bare eye, 
even tho he may be tempered by cloud. It is unlikely that you can see 
Venus against the solar disc, even tho in theory it is just within 
bare-eye resolution. 
    Thru safe filters, like the front end filter of your telescope 
held before the eyes, you MAY can spot the black pinprick of Venus. 
This is still a feat of keen eyesight. If you show the transit to 
others, 
    For this reason I feel it is hazardous to hand out the solar 
glasses, like those for solar eclipses. In an eclipse there is gross 
change in the appearance of the Sun that is readily seen thru these 
glasses. In the transit, Venus is at the threshold of resolution for 
good vision and people may miss seeing her. 
    The possibility arises that people may fiddle with the solar 
glasses in hazardous ways or try to see Venus without them. Children 
away from supervision may horse around with the glasses. Disastrous 
consequences can result from such unstructured use of the glasses. 
filtered view
 -----------
    ALL optics used for direct viewing the transit MUST have solar 
filtration devices fitted to them. Those used for projecting the Sun 
onto a screen MUST be guarded or shielded against looking directly 
thru them. Regardless of your personal experience with fitlered solar 
viewing, please mind well that other people observe your actions, 
which speak orders louder than your words. Stay well within bounds of 
safe operation for solar viewing apparatus. 
    Have a properly-made solar filter for the front end of your 
optics. There is no safe filter for the back end at the eyepiece. If 
your scope has a filter fitting over the eyepiece, please discard it 
before it falls into ignorant hands. 
    Do not try to make your own filter with assorted dense materials. 
    There are articles out there that piously claim that a such-&-such 
snack bag plastic is safe but there is no simple and sure way to tell 
if the sample in hand is that certain kind. 
    By April and definitely by May 2012 there could be few solar 
filters left in stock at astronomy dealers. In addition to the transit 
there is an annular eclipse in May in western United States and a 
total eclipse in the South Pacific in November. These caused extra 
demand for solar filters. 
    I hope you still have suitable filters from previous eclipses or 
the 2004 transit.
Projected view
 ------------
    Projection onto a screen from your optics is a safe way to show 
the transit to many people at once. Guard the instrument by barriers 
or shields against looking into its eyepiece. Venus is easily spotted 
in the projected image and she can be marked on the screen to show her 
progress across the Sun.
    A sun-cone or sun-funnel can be made from cardboard and tracing 
paper. The narrow end is strapped around the eyepiece. The wide end 
is covered with smoothed and taped tracing paper. The Sun is focused 
thru the eyepiece onto the paper to form an enlarged image. It is 
viewed on the paper from the wide, upper, end of the cone/funnel.
    Projection usually lets the full strength of sunlight into the 
telescope, strongly heating the eyepiece area. The scope should be 
capped orcovred between views.
    Pinhole projection, common for solar eclipses, will not show 
Venus. She is too small and will be diffused out of sight.
    Imaging devices, cameras, are a possibility. attached to the 
eyepiece end of the scope and displayed on a computer or television 
screen this method can accommodate a large number of viewers. 
    Make SURE your apparatus is rated for direct input of solar rays! 
    Even with a front-end filter some imaging units could be burned to 
death by sunlight entering them. Consult with the device manufacturer. 
    In case of clouds you can arrange viewing by Internet taken from 
an other location in the clear. Test the availability and reliability 
of Internet signal at your viewing site before the transit. 
Helioscopic views
 ---------------
    I use this term to mean specialty devices to observe the Sun in 
other than plain whole-spectrum white light. Typical examples are 
hydrogen-alpha and coronascopes. These will show amazing structure on 
the Sun that changes within minutes but suffer from severely dim image 
under outdoor daylight.
    You may have seen the SUn thru one of these devices at starparties 
or conventions and had to hood yourself to keep daylight out of your 
eyes. The sight of a inky black Venus spot sitting on top of a solar 
flare can be incredible!  
    An other possibility is that the helioscope may show prominences 
or flares right at the ingress point. Venus could then be silhouetted 
against that feature before she enters the solar disc! This could be a 
way to alert others in your party, observing in white light, to be 
ready for the first contact. 
Photography
 ---------
    Photographing the transit is the same as taking pictures of the 
Sun for an eclipse. You may attach the camera to the eyepiece end of 
the telescope with the dame couplings and fittings and use the same 
settings for exposure. For digital images, you have the chance to edit 
the pictures to remove defects like light leaks and flare.
    Hold the camera up to but not touching the eyepiece. Aim straight 
into the eyepiece, keeping the camera optical axis (centerline of the 
lens) in line with the exit beam of the scope. The viewing screen of 
the camera is a far better means of framing than the viewfinder of a 
chemocamera. You may have to block stray light from intruding into the 
camera with a dark cloth loosely wrapped around the camera and 
eyepiece. Hold your breath, stand still, gently press the shutter 
button. Let the camera do its thing. 
    The major defect you'll suffer is focusing. If you can force the 
focus to infinity, do so. Else hope the camera relaxes to some far 
setting when confronted with a strange scene like the inside of a 
telescope. 
    You can photograph the projection screen as an ordinary landscape 
scene with no special adjustment of the exposure. Keep direct sunlight 
out of the camera by shading its lens with your hand. This same method 
works for photographing a computer or television screen. 
    Be sure to take pictures of the people and scene at the viewing 
site! These pictures give extra significance to the transit images. 
Simulation
 --------
    To cover interruptions by clouds you can run a simulation of the 
transit with a computer planetarium program. Use the 'realtime' 
feature to run the animation in pace with the sky. You have to do a 
time set to get the computer clock in synch with true local time. 
    Lacking a computer you could build a mechanical model from a thin 
steel white=painted sheet and a round magnet. Move the magnet over a 
drawn solar disc in step with the progress of the transit. 
Conclusion
 --------
    This is the second of the current pair of transits, the previous 
one being in 2004. After this one there are NO MORE chances for the 
next 105 years! Neither you nor anyone living today nor anyone born in 
the next decade or so will ever see the next pair of transits. They 
come in 2117 and 2125. 
    The killer is weather. This slaughtered many expeditions in the 
1760s and 1800s, treks litterally lasting months from Europe only to 
end with astronomers huddled in a tent pelted by heavy rain. 
    In spite of advances in science and industry we still can not 
confidently foretell weather even a few days in advance! Yet, and I 
kid you not, when I asked around for a global visibility diagram of 
the 2012 transit, there were none of modern design. I had to avail of 
charts from my transit of Venus textbook that was in wide use thru the 
whole of the 20th century. It was written to prepare for the previous 
pair transits in -- hold your hat -- 1874! Yes, it is spot on for 
delineating just where the next transits, in the appallingly far off 
21st century will be visible . 

 Last update on 03 June 2012

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