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The Venus Transit 2004
Walkiry writes "In just 47 days our friendly neighbour planet Venus will be passing right in between Earth and good ol' Sun, giving us the chance to see a small black spot going accross the disk (last one was in 1882). This is called the Venus Transit. The interesting thing is that there is a project asking for volunteers to perform their own measurements of the phenomena and submit their own results, in what will be the first accurate and public measurement of an extraterrestrial distance. Do you have a spare telescope and some free time on June 8th?"
Of course we do. What did you think we would be doing, going on dates with women?
Okay, everybody stare directly at the Sun.
Ahhh, My EYES! The goggles do nothing! (Damn you /.)!
"giving us the chance to see a small black spot going accross the disk"
"If you think nobody cares if you're alive, try missing a couple of car payments." Earl Wilson
...accurate and public measurement of an extraterrestrial distance.
Maybe it's just me, but somehow those two words don't seem to quite go together.
Nothing disturbs me more than blind loyalism towards some unrealistic and over-idealistic notion of one's nationality.
This is slashdot - what do you think?
Although you should have also mentioned that men are from Mars and Women are from Venus to get the most from the geek crowd here.
From excellent karma to terible karma with a single +5 funny post...
What equipment and observing method are you going to use? Will you project an image of the Sun on a screen? Will you use a camera? Is it already available or will you have to build (buy) it?
I plan on buying a 12" Celestron and doing my observations *with my naked eye*, like a MAN! What kind of wuss would use a screen or a camera? Astronomers seem to have lost the direct feel of things these days, with all them modern equipments...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
sounds like the name of a public transportation company...
Apaprently, the next Venus transit after this one will be in 2012, but the next two after that won't be until 2117 and 2125. Looks like a once in a lifetime deal. (source: http://sunearth.gsfc.nasa.gov/eclipse/transit/venu s0412.html)
Homer: It's like you're from Venus... ...and you're from Mars.
Marge:
Homer: Oh, sure, give me the one with all the monsters.
Nyo nyo, the Neko Boy has spoken.
It was in a situation like that that Venus athmosphere (its clounds) was discovered, when Venus was against the sun an astromer saw a fog over the planet. A lot of light passed trough where previously was thoug to be solid.
This is what i found in Wikipedia on Venus Transits:
"Transits of Venus, when the planet crosses directly between the Earth and the Sun' visible disc, are important astronomical events. The first such transit was observed on December 4, 1639 by Jeremiah Horrocks and William Crabtree. A transit in 1761 observed by Mikhail Lomonosov provided the first evidence that Venus had an atmosphere, and the 19th century observations of parallax during its transits allowed the distance between the Earth and Sun to be accurately calculated for the first time. The previous set of transits of Venus occurred within the interval of 1874 - 1882, and the next set of transits will occur in the period of 2004 - 2012."
"Anyone who quotes me in their
can't see it from north america!
Most astronomical events seem to not be visible from or get clouded out in my area.
no big sig
What's proabaly better is a projection scope. A prpoer one is very expensive, but you can just hold any convex lense or piece of shirt cardboard with a really tiny hole in it above a piece of white paper. You'll need very good resolution to see this though, so you should probably calculate that ahead of time.
Sig:Why copyright isn't a fundamental human right
- Your screenshot is a PNG image, not JPEG.
- If you use Windows XP, tune your ClearType settings using ClearTweak and enjoy crisper text.
Cheers,CD
Use ISO 8601 dates [YYYY-MM-DD]
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you should go here
I have no developed opinion on the bararity of foo. -homeobocks, Gentoo Forums
Damn filters
How long should I stare at it ?
The Kruger Dunning explains most post on
According to that website, this will be visible in parts of Europe, Africa, and Asia. It is pretty light on detail, but according to this site parts of it will be visible from Australia and the eastern parts of North and South America.
W00t !!!
June 8th is my 21st birthday! Finally, a good excuse to have a birthday completely alone, without that damned interference from friends or family. "Sorry, can't have dinner with you, I'll be "making observations" until sunset!"
Do we have any photos of the last one?
Benmore Peak Observatory (http://www.observatory.org.nz) in New Zealand's South Island will be hosting a bunch of visitors for this one. Not only is the view of Venus going to be good, so is the view of the lakes and snow-clad mountain peaks around it. I was there in 2000 and it's just absolutely outstanding (and they always have lots of icy cold beer)! Thoroughly recommended.
Despite warnings every year people get blinded because they wanted to see a partial eclipse or some other solar event directly.
Use a telescope or binoculars and project the image onto a piece of white cardboard or paper.
Even just a few seconds can ruin your eyesight so be careful. It's no joke.
I'm personally looking forward to being gouged for price-hiked solar filters, just like I was gouged for a price-hiked barlow lens during the last close encounter with Mars. :o)
Does anyone have more specific info on how long it'll take for the full transit? Are we talking just a few hours, like an eclipse?
-ZOD-
Why is it this reminds me of "Day of the Triffids?"
There's a little black spot on the sun today...
Intolerance for ambiguity is the mark of the authoritarian personality.
I have a compact dick :-)
...
On a serious note: you do not know what a troll is. Or maybe you do
Use ISO 8601 dates [YYYY-MM-DD]
I saw it the last time round. Wasn't much to speak of.
The other kind of sun filter fits over your eyepiece or inside your eyepiece. I once had a 2.4 inch refracting telescope that came with this piece of welder's glass that fit over the eyepiece. I never used it because I was warned not to.
The advantage of the objective sun filter (the ones I have seen advertised are aluminized mylar) is that 1) it blocks out intense sunlight before it even gets to your telescope, and 2) it is exposed to no more than normal sun intensity because it hasn't been concentrated by the telescope.
The wee bit of welder's glass at the telescope eyepiece is unsafe because it is getting the full focus of sunlight from the telescope and the thing and crack from the heat and then your eyeball is in peril.
The other safe method is projection through the telescope on to a piece of paper. Safe for one's eyes -- I ruined my beginner's refractor doing that because the heat cooked a cheap plastic element in the one eyepiece it came with.
You must be doing the same drugs as that Atriedes fellow. Since the drugs give you visions, you can see stuff whether or not your eyes have been burnt down to eye sockets.
Find the biggest paper cup or popcorn bucket possible, tape thin paper over the top and poke a hole in the base. Point at sun, view image on paper. It's easy enough to teach the kids in the neighborhood when the parents wonder what the strange guy with the paper cup is doing.
If the image isn't large enough, simply pull the paper off and project in the usual way. The paper cup is easy enough for kids to hold. For some reason, flat sheets turn into crumpled useless things when exposed to kids.
...cause drought
...have been mistaken for mere clouds
...are part of a worldwide forced immunization program Or maybe surplu population reduction. (warning...annoying audio)
...is a geoengineering project headed by the Illuminati.
My GOD! They've even invaded the Post Office
Hell..I can't keep up with these fools either. The only solution I fear, is the #4 loon mallet. Yes...I said the #4. This is a serious case.
There's a little black spot on the sun today
It's the same old thing as yesterday
There's a black hat caught in a high tree top
There's a flag-pole rag and the wind won't stop
I have stood here before inside the pouring rain
With the world turning circles running 'round my brain
I guess I'm always hoping that you'll end this reign
But it's my destiny to be the king of pain
There's a little black spot on the sun today
That's my soul up there
It's the same old thing as yesterday
That's my soul up there
There's a black hat caught in a high tree top
That's my soul up there
There's a flag-pole rag and the wind won't stop
That's my soul up there
I have stood here before inside the pouring rain
With the world turning circles running 'round my brain
I guess I'm always hoping that you'll end this reign
But it's my destiny to be the king of pain
There's a fossil that's trapped in a high cliff wall
That's my soul up there
There's a dead salmon frozen in a waterfall
That's my soul up there
There's a blue whale beached by a springtime's ebb
That's my soul up there
There's a butterfly trapped in a spider's web
That's my soul up there
I have stood here before inside the pouring rain
With the world turning circles running 'round my brain
I guess I'm always hoping that you'll end this reign
But it's my destiny to be the king of pain
There's a king on a throne with his eyes torn out
There's a blind man looking for a shadow of doubt
There's a rich man sleeping on a golden bed
There's a skeleton choking on a crust of bread
King of pain
There's a red fox torn by a huntsman's pack
That's my soul up there
There's a black-winged gull with a broken back
That's my soul up there
There's a little black spot on the sun today
It's the same old thing as yesterday
I have stood here before in the pouring rain
With the world turning circles running 'round my brain
I guess I always thought you could end this reign
But it's my destiny to be the king of pain
King of pain
King of pain
King of pain
I'll always be king of pain
http://brandonbloom.name
One line blog. I hear that they're called Twitters now.
The goggles do nothing!
The Venus Transit 2004 almost sounds like it would be the latest in a long-running series of pr0n flicks.
the singular of "phenomenon" remains "phenomenon", and not "phenomena". Jesus! Pay attention! Spelling is not diifi^H^H^H^H hard.
Damn the anti-American universe. I bet it has to do with the United Nations somehow, those hippie-commie bastards.
It's the French. I have it on reliable authority that Venus has Letters of Transit signed by General deGaulle himself. They cannot be rescinded. Not even questioned.
When all you have is an axe, everything looks like a grindstone.
"There's a little black spot in the sun today..."
Goals for 2011: 1. Stop plate tectonics. 2. Prevent animal predation. 3. End supernovae now. 4. Rid the world of evil.
do not look directly at the sun with your remaining eye!
The Kruger Dunning explains most post on
the last time an eclipse was viewable in my area, i used a couple of polarizers to look at it and it worked pretty well
you adjust the light that gets through easily by just turning them with respect to each other.
might even work in front of a telescope
I made a quick video using Celestia of the Venus transit. It requires Divx and it's about 330KB in size and runs for 18 seconds.
:)
Here is the link. Ugh, be gentle.
This also just gave me an idea. Being in North America, I might use Celestia to watch this happen in real time on June 8!
THE VENUS TRANSIT: A CALL FOR GLOBAL ONENESS
June 6-8, 2004
By Kiara Windrider and The Experience Foundation
The darkest hours of night come just before the dawning of a new day. There is no question that Earth faces a tremendous crisis today, a painful "dark night of the soul," even the possibility of catastrophic obliteration. Yet, according to the prophecies and calendars of many ancient traditions, this Age also represents a time of hope. We are moving into a time of evolutionary renewal, a time of global purification, even what some refer to as the dawning of a Golden Age!
The ancient Mayans developed a calendar system that is very relevant to these times. It can be seen as a cosmic timing code and is prophetic in the sense that it reflects a deep understanding of long-term cycles of creation. As evolutionary cycles of cosmic energies are absorbed into Earth's electromagnetic fields via the Sun, human consciousness responds to these impulses in a predictable manner, following a cosmic pattern of dark and light.
The Mayan calendar describes the sequence and timing of these patterns. According to this calendar, the year 2012 reflects the end of certain cycles of history based on duality and separation and represents the birthing of a Golden Age of Enlightenment.
Once we begin to use the Mayan calendar to understand the deeper significance of world events today, this claim no longer seems as improbable as it may first appear. Out of deepest darkness comes the greatest light. In his studies of the Mayan calendar, Dr. Carl Johan Calleman points to a key event taking place now which might well serve to initiate this extraordinary opening to planetary light.
The planet Venus is rich in archetypal symbology. It is often known as the Morning Star, the Bringer of Light. It is related to love, human unity, beauty and oneness. On June 8, 2004, the path of Venus directly crosses over the disc of the Sun, an eclipse lasting for the space of seven hours. The energies of Sun and Venus blend together, and as these blended radiations make their way into the Earth's electromagnetic fields, it weaves the energies of love and unity into the mass consciousness of the planet and potentially
into the hearts of every man, woman and child alive on Earth!
Interestingly, Venus transits always come in pairs. The second passage of Venus across the Sun's disc takes place on June 6, 2012. The eight-year period in between represents a "doorway" through which Unity consciousness will come to dominate the mass consciousness of the Earth. Since this is a 130-year cycle, there are few humans alive today who have experienced this transit, yet it can be seen that every time this transit has taken place in human history, it has represented a new level of harmonization on the planet. It is interesting to note that the Taj Mahal, one of the greatest monuments to Love in human history, was built during the Venus
Transit of 1631-1639 AD!
The transition into Unity consciousness could be turbulent. As old structures of human consciousness collapse, it may be accompanied by a degree of darkness and destruction. This process should be seen in proper perspective. "When the light hits," as Jose Arguelles, puts it, "the dark gets tough"! This current "doorway of Venus" is especially significant because it remains open until 2012 AD, the completion our current cycle of human evolution. Some refer to this date as the end of linear time or as the end of a period of human consciousness conditioned by separation and duality. The Mayans refer to this time as the Return of Quetzalcoatl, the Plumed Serpent, and look to this eight-year doorway as the timeframe within which the mass enlightenment of humanity will take place.
We are calling people all over the world to observe the days leading up to this Venus Transit, June 6-8, as a time for opening to the bright impulse of cosmic energy that is streaming into the mass consciousness of Humanity. What are our highest dreams and hopes? What is our gr
weee june 8th, i hope its good luck.
"In just 47 days our friendly neighbour planet Venus"
Why "friendly?" Because they don't try to invade us as often as Mars does?
Proper and accurate observations of the transit could provide crucial evidence that would undermine the doctines of the anti-intelectual, right-wing, pro-coporatist secret society whose members have taken over the U.S., British and Israeli governments. Any weakening of these doctrines would threaten the ...
Well, you get the idea. To really fill the theory out we need some mention of the Kennedy assasinations (amoung others), the Knights of the Templar, Free Masons, Yakuza, Tibetan Bhudist warrior-monks, Cabalist mysticism/numerology, international bankers (of whatever persuasion), and a sprinkling of Lovecraftian Elder-Gods.
The sad part is, however, it just couldn't be more frieghtening or depressing than the truth (and not nearly as romantic).
But wait till I start my braille keyboard selling business...
To do list for Windows
Spare telescope, yes.
Spare set of measuring/viewing equipment that will let me use cet telescope without blinding myself while pointing it at the sun and looking through the 300x magnifying lense; no!
I think I'll leave this to the people who either don't value there eyesight, or have very good tinted googles.
-Millions of Monkeys, Millions of typewriters, 6 hours of sorting through faeces encrusted pages to find: This post
Oui! I've always wanted to see these celestial events , but had no telescope!. Can you guys how to build a simple telescope - quick n easy --so that i can see venus?
Why does yahoo do this
Buñuel tried this before.
To do list for Windows
I visited Gary and the guys last year, so I know what you mean about the beer! At the end of the day I was seeing plenty of stars and I didn't need no steenken telescopes to do it! I have no idea how they get any work done. But you are right, the views are incredible. Amazing scenery. It's no wonder Jackson filmed LotR down there.
Can't wait to do it again.
Or did you forget Alaska was on the west coast of America, you insensitive clod!
Truly it was a most exquisite and memorable sight. The sun was already beginning to put on the ruddy hues of sunset, and there, far in on its face, was the sharp, round, black disc of Venus. It was then easy to sympathise with the supreme joy of Horrocks when, in 1639, he for the first time witnessed this spectacle. The intrinsic beauty of the phenomenon, its rarity, the fulfilment of the prediction, the noble problem which the transit of Venus enables us to solve, are all present to our thoughts when we look at this pleasing picture, the like of which will not occur again until the flowers are blooming in the June of A.D. 2004.
Robert Stawell Ball, The Story of the Heavens (1885)
Don't forget the Lunar eclipse on 4th of May!
Not quite as special but definitly more dramatic!
Not only do I get to see amazing astronomical events, while I am there I travel around and see wonderful and interesting parts of our own planet!
To pay for my vacations to these selected events, I have established travel investment funds (setup many years in advance) for:
I also keep an emergency fund that allows me go anywhere in the world at a moments notice to see a Supernova bright enough seen with the naked eye. I had such a fund in place which allowed me to rush from California to Australia some 21 hours after the discovery of 1987A (24 Feb 1987).
Maybe next naked eye supernova viewable in my hemisphere. But if not, I have another supernova fund ready ...
I first learned about the Transit of Venus, in the early summer of 1970, during a Morrison Planetarium program of the California Academy of Science. At the age of 9 I decided that I wanted to see next transit.
I have waiting patiently for 34 years to make my transit observations. It is now only a few dozen days away!!!
chongo (was here)
...accurate and public measurement of an extraterrestrial distance.
... determine these orbits far more accurately (by one or two orders of magnitude) than do the optical data." The report for the current latest general ephemeris on public release DE405, here, says much the same.
I doubt that the public project related to the 2004 transit is intended to obtain more accurate measurements than already exist, for the distances and timings associated with Venus.
For all of the inner planets, even the best professional optical telescope measurements are already so much less accurate than modern non-optical measurements, such as radar-ranging and spacecraft measurements, that optical data (except for the outer planets) did not contribute at all to the final data-sets that went to make up the current best professional ephemerides. This JPL report, about the latest-but-one of the professional solar-system ephemerides, DE403, says that "all of the optical observations for the Sun, Mercury, Venus and Mars were omitted from the least-squares adjustments leading to DE403. Newer and more accurate data-types
The project for measuring the timing of the June Venus transit looks like mainly an exercise in public awareness and education. Maybe there is also an aim of historical reconstruction, for doing something like re-assessing the performance of the old astronomers who measured previous transits, in an age when optical telescopes still did provide the only serious measurements available.
-wb-
Just use the telescope to project to a flat clear surface, like they explain here with binoculars. Easy to do, and quite safe because you don't even have to get behind the telescope itself.
... from the UK the transit starts at approx 6:19am. Who's getting up at that time?
I'd love to do this!
Let's see... convert UTC to my time... carry the one....
YAY! I won't be needing all those protective glasses/filters for my observations; the sun doesn't hurt the eyes as much AT MIDNIGHT.
Damn.
setting up my telescope+Thousand Oaks solar filter with a webcam and broadcasting the transit over the web but given my location (.ky.us), only the final 25 minutes of the transit will be visible so I'm afraid it won't be worth the effort. Perhaps some folks in Europe will do this, though.
Have you ever actually tried to show a woman stuff through a telescope? THAT, my friends, is a chick magnet. Atleast it was the last few times I tried it ;)
The GONG is used to watch the Sun oscillate, or "ring," which provides mighty useful data on the solar interior. Helioseismology, in other words. See http://gong.nso.edu for details.
Credit Line: The GONG is operated by the National Solar Observatory which is operated by the Association of Universities for Research in Astronomy under a cooperative agreement with the National Science Foundation, for the benefit of the astronomical community.
Wow, that's a neat plan!
:( Might have to aim for Easter Island in 2010.
I agree about coordinating travel with astronomical events. I went to Venezuela for the eclipse of 1998 (did you see that one?) and had a blast traveling around the country, seeing things such as Angel Falls and a Llanos safari.
You can find great stuff to do in nearly any country on earth.
Currently I live in Ecuador and won't be able to get to Europe for this.
OTOH, I can't immagine how hard or expensive it will be to get there. LanChile is the only airline that flies to the place, only has two flights a week to Santiago and to Tahiti, and they cost like $800. Unless they plan special runs (and I bet they will), you'll probably want to book a year in advance!
Thomas Pynchon's Mason & Dixon describes the 1761 transit of Venus, written in period-ish language: "The girls have also been observers of the Transit, having cajol'd a Sailor of their Acquaintance into lending them a nautickal Spy-Glass, and smoak'd with Sheep-tallow Candles their own Darkening-Lenses,-- taking turns at the Glass, even allowing their Parents a Peep now and then,-- Jet breathing, "She's really there," Greet adding, "Right on time, too!" and Els,-- hum,-- we may imagine what Els was up to, and what transpir's just as the last of the Black Filament, holding the Planet to the Inner Limb of the Sun, gave way, and she dropp'd, at last, full onto that mottl'd bright Disk, dimm'd by the Lenses to a fierce Moon, that Eyes might bear." Who says telescopes won't get you laid? The book was much published, but seldom sold; it can be had remaindered for $5. Or you could spare yourself the 750+ pages and just stare at the sun for wisdom. Good fun all the same.
Damn! And I thought *I* was a major astro-geek. I'm going to be on the island of Mauritius for the transit. I reserved my spot with one of the eclipse tour companies almost two years ago. This is my first astronomical "expedition" abroad. I will try to capture the transit in digital video straight to hard disk. I've done it for Mars and Saturn before, it works really good for that.
Edith Keeler Must Die
Does anyone know of a good telescope (something that can see the rings around Saturn) and have the ability to transfer video in real-time through Firewire or USB 1.1 or USB 2.0 ? I'm also wondering whether it would be cheaper to attach a DV cam or webcam and would this method still have similar (quality) results?
> (did you see that one?)
1998 was a wonderful eclipse.
I do not see every Eclipse. I'm trading the 08 Apr 2005 Solar Hybrid for the 8 June 2004 Venus transit for example.
Since you live in Ecuador, I would encourage/urge you to travel to the coast and see the Hybrid eclipse (part Annular / part Total). My calculations show that it will be very close to total along the center line in South America. It is worth while to see the Sun in annular mode once in a while.
chongo (was here)
Have you ever actually tried to show a woman stuff through a telescope? THAT, my friends, is a chick magnet. Atleast it was the last few times I tried it ;)
Until she realizes that it isn't actually that big....
Only a guy trolling for ``funny'' points like yourself could come up with something so cliche.
Where did you see the 1998 eclipse? Yes, indeed it was a truly perfect day in Maracaibo. There are two photos of it on my page ... click my URL and scroll down to the Photos section.
Cool, I forgot about that eclipse. Looks like it will be 60% or so in Ecuador, but looks like the path goes through Cartagena, Colombia just before sunset. There's a reasonably good chance I could go up there for that. I wonder if it will be total or annular there -- it's a little hard to tell from the map. Maybe Panama would be better - looks like it goes straight through Panama City, and it's earlier in the path. More expensive to fly to though.
When it is this close to totality, one's thumb (or other opaque object) may be used to block out the solar disk and view the corona. Using a ball on a stick and sighting the Sun behind it will give one multiple seconds of corona viewing. I've used this technique to extend "totality effects" as much as 15 second beyond the official end of the eclipse. I have been told that using a green filter will further enhance the contrast of the corona and allow you to extend the corona viewing even longer.
Also when it is this close to total, you should be able to view the shadow bands. It is best to view then afterwards as the excitement of what the sun/moon are doing will occupy your attention. :-)
One cannot look for the shadow bands and extend the corona viewing time. Given the choice, I'd contentrate on the zone around the solar disk. Unlike long totality eclipses, short totality and near total annular eclipses give one a MUCH better view of photosphere / action near the edge of the solar disk. That alone would suggest skipping the shadow bands this time.
I would try and go as far west as possible so that the sun is as high above the horizon as possible. Of course one would want to be close to the center line ... which becomes critical on
short annular events like this one.
Of course, a ''the deep annular-like conditions'' of the Venus transit do not permit one to do this. :-)
chongo (was here)
At Club Mac we will be having a party that afternoon, with several telescopes (6 have signed up so far, one with a video monitor so that large groups can view at once) at our observatory.
If you happen to be in Sydney that day, it's a good place to view these events from, as we do have a really good view to the west. Last year's transit of Mercury was spectacular. And we had 700 descend upon the observatory for the Opposition of Mars (which was chaotic beyond belief, but a great night).
There's not much info up yet, but here's the link to the observatory's website for the party.
Considering they calculated the diameter of the earth, the distance to the moon and sun, and the reason for total solar eclipses (the sun and moon having the same apparent diameter, but the sun being much larger and further away), I think that they should count.
They also knew the world was round. Columbus didn't sail to prove the world was round. They already knew that, and that's why Isabella was willing to finance him - it wasn't a really risky proposition.
The first sentence is not even right. The REAL quote in FULL of Ball's observation of the 1882 transit of Venus at Dunsink is:
"I venture to record our personal experience of the last transit of Venus, which we had the good fortune to view from Dunsink Observatory of the afternoon of the 6th of December, 1882.
The morning of the eventful day appeared to be about as unfavourable for a grand astronomical spectacle as could well be imagined. Snow, a couple of inches thick, covered the ground, and more was falling, with but little intermission, all the forenoon. It seemed almost hopeless that a view of the phenomenon could be obtained from that observatory; but it is well in such cases to bear in mind the injunction given to the observers on a celebrated eclipse expedition. They were instructed, no matter what the day should be like, that they were to make all their preparations precisely as they would have done were the sun shining with undimmed splendour. By this advice no doubt many observers have profited; and we acted upon it with very considerable success.
There were at that time at the observatory two equatorials, one of them an old, but tolerably good, instrument of about six inches aperture; the other the great South equatorial, of twelve inches aperture. At eleven o'clock the day looked worse than ever; but we at once proceeded to make all ready. I stationed Mr Rambaut at the small equatorial, while I myself took charge of the South instrument. The snow was still falling when the domes were opened; but, according to our prearranged scheme, the telescopes were directed, not indeed upon the sun, but to the place where we knew the sun was, and the clockwork was set in motion which carried round the telescopes, still constantly pointing towards the invisible sun. The predicted time of the transit had not yet arrived.
The eye-piece employed on the South equatorial must also receive a brief notice. It will, of course, be obvious that the full glare of the sun has to be greatly mitigated before the eye can view it with impunity. The light from the sun falls upon a piece of transparent glass inclined at a certain angle, and the chief portion of the sun's heat, as well as a certain amount of its light, pass through the glass and are lost. A certain fraction of the light is, however, reflected from the glass, and enters the eye-piece. This light is already much reduced in intensity, but it undergoes as much further reduction as we please by means of an ingenious contrivance. The glass which reflects the light does so at what is called the polarising angle, and between the eye-piece and the eye is a plate of tourmaline. This can be turned round by the observer. In one position, it hardly interferes with the polarised light at all, whereas in the position at right angles thereto the tourmaline intercepts nearly all the light. By adjusting the position of the tourmaline, the observer has it in his power to render the image of any brightness that may be convenient, and thus the observations of the sun can be conducted with the appropriate degree of illumination.
But such applications seemed to be on this occasion a mere mockery. The tourmaline was all ready, but up to one o'clock not a trace of the sun could be seen. Shortly after one o'clock, however, we noticed that the day was getting lighter; and, on looking to the north, whence the wind and the snow were coming, we saw, to our inexpressible delight, that the clouds were clearing. At length, the sky towards the south began to improve, and at last, as the critical moment approached, we could detect the spot where the sun was becoming visible. But the predicted moment arrived and passed, and still the sun had not broken through the clouds, though every moment the certainty that it would do so became more apparent. The external contact was therefore missed. We tried to console ourselves by the reflection that this was not, after all, a very important phase, and hoped that the internal contact would be more successful.
At length th