ECLIPSE VIEWING SAFETY!
A Solar Eclipse is a truly, truly wonderful phenomena. But one
MUST OBSERVE IT CAREFULLY!
SEVERE eye damage can result if the sun is viewed improperly at any time!!
Safe Methods of Viewing
METHOD 1) Eclipse Glasses
This is the most affordable method. Eclipse glasses are very inexpensive and can be found many places. Just be sure to buy them well before the eclipse, because they will be very hard to come by a day or two before. Make sure that the glasses have the "CE" certification on them.
Eclipse glasses usually consist of a cardboard frame holding two pieces of filtering material where the glass would be in normal sunglasses. The filters remove 99.99% of the Sun's visible light and 100% of the harmful UV. There are now two types of eclipse glasses. The older type has filters made of aluminized Mylar. The newer type uses black polymer lenses. Both will give good protection, but the black polymer type is better all around. They show a more natural color and can be used to look at sunspots any time the Sun is visible. They are more expensive than the Mylar glasses, but well worth the price.
Always check the glasses carefully before each use for pinholes. If you find any, cut the glasses up with scissors and throw them away.
METHOD 2) Special Telescope Filters
These filters fit over the FRONT END of a telescope. Again, they filter out most of the Sun's light. The advantage with this method is that one can see a magnified image of the Sun, with sunspots, granulation, speckles, and other features. The disadvantage is that the filters are more expensive (plus one needs a telescope).
METHOD 3) Welder's Glass
Be careful that you use the right kind of glass! Welder's glass is numbered from 1 to 14 with 14 being the darkest. It is only number 14 glass that is dark enough for solar viewing! And NO STACKING! A pair of number 7's or a 10 and a 4 together DO NOT have the same protection as a single piece of number 14 (see unsafe methods for more details).
METHOD 4) Telescopic Projection
One can get a nice, large, bright image visible to several people at the same time. It requires no special equipment beyond the telescope itself and some sort of flat screen. HOWEVER: It can be VERY DANGEROUS unless one knows EXACTLY how to do it properly! Not only can it cause severe and permanent eye damage, but it can also easily set things on fire. USE CAUTION when following these instructions!
Unsafe Methods of Viewing
Keep in mind that this is by no means an exhaustive list. People have historically been very clever in coming up with stupid ways to observe the Sun. In general, when you're considering whether or not a particular method is SAFE, ask yourself these questions:
"Is this method I'm using SPECIFICALLY designed for solar viewing?"
"Do I know EXACTLY what I'm doing?"
If the answer to either of these questions is "no," then for your vision's sake, don't try it!
(a)Sunglasses (b)Multiple Sunglasses
(c)Mylar Balloons (d) Mylar Food Wrappers (Pop Tart Bags, etc.)
(e) Smoked Glass (f) X-Ray Film
(g) Film Negatives (h) CD's or CD-ROM's
(i) Stacked Welder's Glass
(j) Stacked Welder's Glass
(k) Liquid Filters
(l) Eyepiece Solar Filters
(m) Eclipse Glasses and Telescopes Together
Varun's Blog - At the Speed of Light !
A fact is a simple statement that everyone believes. It is innocent, unless found guilty. A hypothesis is a novel suggestion that no one wants to believe. It is guilty, until found effective. ~Edward Teller
A very warm welcome to my th reader.Why speed of light ? Well, the aim of this blog is to reach the impossible by exploration and scientific fervor. Exploration never ends, knowledge never dies but Speed of Light can be achieved ....
Tuesday, March 21, 2006
Thursday, March 16, 2006
NASA astronauts may need quake-proof houses as they are going back to the moon.
The moon is seismically active.Between 1969 and 1972, Apollo astronauts placed seismometers at their landing sites around the moon,instruments faithfully radioed data back to Earth.
And what did they reveal?
There are at least four different kinds of moonquakes:
(1) deep moonquakes about 700 km below the surface, probably caused by tides;
(2) vibrations from the impact of meteorites;
(3) thermal quakes caused by the expansion of the frigid crust when first illuminated by the morning sun after two weeks of deep-freeze lunar night; and
(4) shallow moonquakes only 20 or 30 kilometers below the surface.
The first three were generally mild and harmless.Between 1972 and 1977, the Apollo seismic network saw twenty-eight of them; a few "registered up to 5.5 on the Richter scale". A magnitude 5 quake on Earth is energetic enough to move heavy furniture and crack plaster. Shallow moonquakes lasted more than 10 minutes. The moon rang like a bell.
On Earth, vibrations from quakes usually die away in only half a minute. The reason has to do with chemical weathering: "Water weakens stone, expanding the structure of different minerals. When energy propagates across such a compressible structure, it acts like a foam sponge—it deadens the vibrations." Even the biggest earthquakes stop shaking in less than 2 minutes.
The moon, however, is dry, cool and mostly rigid, like a chunk of stone or iron. So moonquakes set it vibrating like a tuning fork. Even if a moonquake isn't intense , it just keeps going and going.
"Any habitat would have to be built of materials that are somewhat flexible," so no air-leaking cracks would develop. "We'd also need to know the fatigue threshold of building materials," that is, how much repeated bending and shaking they could withstand.
What causes the shallow moonquakes? And where do they occur? The Apollo seismometers were all in one relatively small region on the front side of the moon, so we can't pinpoint [the exact locations of these quakes].
We're especially ignorant of the lunar poles. That's important, because one candidate location for a lunar base is on a permanently sunlit region on the rim of Shackleton Crater at the Moon's south pole.
Proposals for deploying a network of 10 to 12 seismometers around the entire moon is on, to gather data for at least three to five years. This kind of work is necessary, to find the safest spots for permanent lunar bases.
Other planets must be shaking too.We have to study the moon before establishing habitats on mars or beyond.
NASA NEWS RELEASE
Posted by Varun Khetarpal Labels: moon
Saturday, March 11, 2006
Solar minimum has arrived,Sunspots have vanished & Solar flares are nonexistent. The sun is utterly quiet.
This week a storm is coming--the most intense solar maximum in fifty years.The next sunspot cycle will be 30% to 50% stronger than the previous one.
Solar maxima can be intense, as in 1958, or barely detectable, as in 1805, obeying no obvious pattern.
The key to the mystery is a conveyor belt on the sun.
We have something similar here on Earth—the Great Ocean Conveyor Belt, popularized in the sci-fi movie The Day After Tomorrow. It is a network of currents that carry water and heat from ocean to ocean—refer to the diagram below. In the movie, the Conveyor Belt stopped and threw the world's weather into chaos.
Above: Earth's "Great Ocean Conveyor Belt."
The sun's conveyor belt is a current, not of water, but of electrically-conducting gas. It flows in a loop from the sun's equator to the poles and back again. Just as the Great Ocean Conveyor Belt controls weather on Earth, this solar conveyor belt controls weather on the sun. Specifically, it controls the sunspot cycle.
What sunspots are--tangled knots of magnetism generated by the sun's inner dynamo. A typical sunspot exists for just a few weeks. Then it decays, leaving behind a 'corpse' of weak magnetic fields."
Enter the conveyor belt.
"The top of the conveyor belt skims the surface of the sun, sweeping up the magnetic fields of old, dead sunspots. The 'corpses' are dragged down at the poles to a depth of 200,000 km where the sun's magnetic dynamo can amplify them. Once the corpses (magnetic knots) are reincarnated (amplified), they become buoyant and float back to the surface." Presto—new sunspots!
All this happens with massive slowness. It takes about 40 years for the belt to complete one loop. The speed varies "anywhere from a 50-year pace (slow) to a 30-year pace (fast)."
When the belt is turning "fast," it means that lots of magnetic fields are being swept up, and that a future sunspot cycle is going to be intense.
Who's right? Time will tell. Either way, a storm is coming.
Posted by Varun Khetarpal Labels: solar system
Thursday, March 09, 2006
The facts available about "Universe" on various websites/books are under big question marks ???
As most of these Facts are cooked around the "Facts" assumed by people living in "Imaginary World" and "Information" provided by few agencies.
Most of these facts are already available in one or the other form in Ancient Vedas - If we start Exploring things from them, we will have better picture of it. A number of old indian researchers have already worked alot in this area. Somehow due to lack of resources and encouragement, they had stopped their researches in betweeen as part of Brahmanda Shastra/Vigyan. We need to combine this "Gyan" with modern tools to actually know Whats and Hows of the Brahmanda/the Universe.
You will not belive but if ONE calculates correctly using information and methods provided in Vedas, one can actually calculate exact relative position of each and every object present in Brahmanda without using any modern tool.
So UnExplore to Explore Universe
Posted by Mukesh Kumar Labels: universe
Consider this: Signs of life are found on a planet, say, Venus (this is just an example), it definitely DOES NOT mean that we have found beings who will come around in flying saucers to say "hi". If the life forms are nothing more than worms, we will call them aliens.
This is exactly why the SETI is the "Search for Extra Terrestrial Intelligence". It does not search for alien life, it searches for alien intelligence. Therefore, even if some form of life was living within jupiter, we wouldnt know until the day we make an explorer heat resistant enough to go there.
Posted by RG Labels: Aliens
Monday, March 06, 2006
Firstly I should mention that there is another fabulous discovery in the solar system. Jupiter has another red spot.Christopher Go of the Philippines photographed it on February 27th using an 11-inch telescope and a CCD camera:
There are trillions and trillions of galaxies in the universe which in turn have billions of massive stars.So why isn’t the universe hot ? Instead it is freezingly cold.Why doesn’t the universe burn due to heat.Some people would argue that the space is all vacuum but its not like that everywhere.Some places are still having matter like regions of dark matter instead of vacuum.
The thing is energy infact Heat travels from the stars to other parts of the universe through the process of radiation and in this process there is no need of any medium.This is so because heat infact Light travels in the form of electromagnetic waves which are transverse in nature and don’t require a medium for propagation.
Now the light (carrying heat) reaches other planets or I should say heavenly bodies which in turn get heated up and the heat is generated on them and in their surroundings. In all this process the medium stays unaffected hence the space remains unaffected and the universe remains unaffected.Due to this reason its very cold.
Posted by Varun Khetarpal Labels: universe
Wednesday, March 01, 2006
Do nearly exact copies of you exist in other universes? If one or more of the multiverse hypotheses is correct, then quite possibly they do.
The universe started with an explosion called big bang which occured 14 billion years ago.Ever since the universe is expanding.It was an explosion "of" space, not an explosion "in" space.
In earlier times people thought the earth is flat.According to Ptolemy,the Earth stood at the center, surrounded by eight spheres that carried the moon, the sun, the stars and the five planets known at that time, Mercury, Venus, Mars, Jupiter and Saturn.
This is one of the analogy I can put forward.It is called Balloon analogy.A good way to help visualise the expanding universe is to compare space with the surface of an expanding balloon.COnsider a balloon with dots marked on its surface.If the balloon is blown up the distances between the dots increase in the same way as the distances between the galaxies.Universe - balloon , galaxies - dots on the balloon.The surface is homogeneous with no point which should be picked out as the centre. The centre of the balloon itself is not on the surface and should not be thought of as the centre of the universe.So to say that what is the centre of the universe becomes a little meaningless.... read this ....
1. The 2-dimensional surface of the balloon is analogous to the 3 dimensions of space.
2. The 3-dimensional space in which the balloon is embedded is not analogous to any higher dimensional physical space.
3. The centre of the balloon does not correspond to anything physical.
4. The universe may be finite in size and growing like the surface of an expanding balloon but it could also be infinite.
5. Galaxies move apart like points on the expanding balloon but the galaxies themselves do not expand because they are gravitationally bound.
Till now people go by the hubble theory that galaxies are moving far apart due to the continuing expansion force.Rest is exploration based.We cannot assume - We have to EXPLORE and then match our observations with theoretical concept.
Posted by Varun Khetarpal Labels: universe
This is science !
Photos of Comet Mcnaught !
Astro-photographer? Send your photos to email@example.com and have them featured on this blog with your name. Comet Mcnaught : Pictures taken with Nikon D100 on 19/1/07 from Manning Point, northern NSW, Australia by Mr. Peter Enright.