adobe photoshop 6 book Adobe Creative Suite 5 Web Premium software download adobe photoshop lightroom crack leagal adobe photoshop software for cheap Adobe InCopy CS5 for Mac software download actualizacion adobe illustrator 10 download adobe acrobat tryout crack Adobe Photoshop Lightroom 3 software download adobe illustrator cs2 12.0.0 crackz serialz adobe acrobat 70 professional free download Adobe Dreamweaver CS5 software download adobe photoshop elements 5.0 scrapbook download adobe acrobat standard Adobe Creative Suite 5 Design Premium software download adobe illustrator demos 5.0 acrobat adobe download free reader Adobe Photoshop CS5 Extended software download adobe illustrator parallogram total training for adobe photoshop cs Adobe Creative Suite 5 Master Collection software download adobe creative suite academic adobe photoshop cs3 mac keygen Adobe Acrobat 9 Pro Extended software download scrolling in adobe illustrator downloading software acrobat adobe form client Adobe Premiere Pro CS5 software download adobe photoshop cs2 filters serial number adobe acrobat 6.0 Adobe Illustrator CS5 software download adobe photoshop killer tips

How to Block Out The Sun

August 6, 2008 on 11:19 am | In Astronomy, Solar System |

Eclipses are one of those events that when they happen, everyone who can wants to watch it. They’re rare enough that I’ve never had a total solar eclipse happen where I was, but I once had an almost-total eclipse happen when I was in New York back in 1995 — we had an 88% eclipse.

It was strange, because the Sun didn’t look any different with the naked eye, but it felt cooler, like the Sun was giving off light but not heat. What’s more, is that if I made shadows on the ground, I could see that the sunlight that shone through was misshapen, like it had a chunk taken out of it, like this picture of a kitchen skimmer’s shadow:

I later learned that this was working like a pinhole camera, which is a way of seeing how much of the Sun is blocked without looking at the Sun itself, by making an image of it instead.

So how do solar eclipses happen, anyway? When the Moon passes in front of the Sun, from the point of view of someone on the Earth, it can make a shadow on the Earth, and we’ve actually seen it from space:

When this happens, we get what’s called a total solar eclipse, where everyone who’s in that shadow sees the Moon entirely block out the Sun, during the day. During this time (and no other), you can see the Solar Corona (the super-hot part of the Sun’s atmosphere) with the naked eye:

But sometimes, even when the Moon passes between the Sun and the Earth, it doesn’t make a shadow on the Earth! This is because the Moon has a huge variety in its distance from the Earth. When it’s closest to the Earth (perigee), it’s 220,000 miles away. But when it’s farthest from the Earth (apogee), it’s 252,000 miles away, which means it appears about 15% smaller in diameter in the sky:

Well, when the Moon looks large (near perigee) and passes between the Sun and Earth, it makes a shadow on Earth and we get a total solar eclipse. But when it’s near apogee, the Moon looks smaller, and sometimes even appears smaller than the Sun in the sky. When that happens, even when the Moon passes between the Sun and the Earth, we don’t make a shadow on Earth:

But instead, what we see, rather than a total eclipse, is an annular solar eclipse, where the Moon blocks out the central part of the Sun, but appears so small that a thin ring (or annulus) of the Sun can always be seen:

So the next time you want to block out the Sun, know that the best way to do it is not just with the Moon, but with the Moon near perigee, or closest to the Earth!


6 Comments »

RSS feed for comments on this post. TrackBack URI

  1. Everybody knows that the way to block out the sun is with a big disk and a remote control:

    image link

    ;-p

    Comment by brian — August 6, 2008 #

  2. […] How to Block Out The Sun | Starts With A Bang! […]

    Pingback by The Daily Links - August 6th « The Four Part Land — August 7, 2008 #

  3. […] Siegel, Astrophysicist, sent in his article “How to Block Out the Sun“, referring to the properties of an eclipse and how they work. He also looks at solar […]

    Pingback by A Mars Odyssey » Blog Archive » Welcome, Everyone, to the 66th Edition of Carnival of Space — August 9, 2008 #

  4. Your personal interesting useful information entails much a person like me and somewhat more to my mates.

    Comment by Terrance Mesenbrink — September 6, 2011 #

  5. Slots of fortune has existed since 08, but has recently been through a number of beauty alterations that leave
    this particular Casino glimpse fresh new along with up-to-date.

    Players arriving at slots of fortune could have a fantastic
    start to their own perform that has a whopping $10, 000 in downpayment
    bonus deals with your 1st 10 deposits.

    Comment by www.totallynsfw.com — March 20, 2013 #

  6. In comparison with other Casinos around, this can be a lower above the
    rest when it comes to producing payouts that will make the buyers content and
    often returning with regard to much more. as well as a variety of once a week promotions that can increase new enthusiasm and also entertaining in order to
    each pay a visit to. Basically decrease the list,
    operate the real money online casino presented, with just a couple time of
    your time, you will possess many additional us dollars in order to perform having about
    high-tech virtual casinos of any model under
    the rainbow.

    Comment by real money online casino — April 1, 2013 #

Leave a comment

XHTML: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <code> <em> <i> <strike> <strong>

Entries and comments feeds. Valid XHTML and CSS. ^Top^ Powered by TopSoftware4Download.com with a personally modified jd-nebula-3c theme design.