Posts Tagged ‘Astronomy’

The path of the Eclipse of the Century

16 July, 2009

GoogleMaps has posted the path of totality for next Wednesday’s eclipse! Check it out…

It stretches from Mumbai across India, into central China and out into the Pacific Ocean. You can zoom in and out. Click on any point of the map and information on first contact (the edge of the Moon’s silhouette touches the edge of the Sun), total eclipse, and last contact, will appear.

We are so psyched. We’re still playing with it. So this post will be short.


Eclipse Map


Did you catch the lunar eclipse

7 July, 2009

A lunar eclipse happened this evening, beginning at moonrise during dusk over Australia on July 7, and setting over western North and South America in their early predawn hours of July 7.

However, the lunar eclipse only entered the southern most tip of the penumbral shadow, making it extremely difficult to observe visually.

Image: Tom Ruen

(See the diagram… The shadow barely nudges the Moon, and not even the umbral shadow.)

Unlike this somewhat unspectacular lunar eclipse, the total eclipse happening later this month promises to be the most dramatic one in our lifetime, partly because it will be the longest one this century.

If you are in India, China or parts of Japan, you may be in luck to catch the total eclipse.

If you are in the majority of the world not within the eclipse’s path, don’t fret. You can still view it “live” and in real time right here.

Eclipse from another world – Jupiter

6 July, 2009

You’ve seen what an eclipse, or transit, of the Sun looks like from Mars. Now here’s Jupiter.

Of the 63 natural satellites orbiting the largest planet in the solar system, five are capable of occulting the Sun. That is, they appear visually larger than the Sun.

They are Amalthea, Io, Europa, Ganymede and Callisto, the latter four being Jupiter’s four largest moons, also called Galilean moons since they were discovered by Galileo Galilei.

The rest are too small or too distant and transit the Sun.

Furthermore, since Jupiter is so large and there are five satellites capable of occulting the Sun, eclipses of the Sun from Jupiter are not particularly rare (unlike Earth!).

Shown in the computer generated picture below are the moons Io and Europa casting simultaneous shadows on the surface of Jupiter.

Author: Richard B

Upsize Sun

4 July, 2009

Exactly how BIG is the Sun that we are trying to stop?

For starters, the Sun makes up 99.8% of the total mass of the solar system. To give you a sense of scale on what that really means, check out the size of the Sun compared to that of Earth and the rest of the planets in the solar system. The proportion of size in the picture below is accurate, but the distances are not.

Our Sun is big. And that’s an understatement.

Planets 2008 (Image: NASA)

Some fun Sun facts

1 July, 2009

Some facts about our one and only Sun.

  • Author: NASAThe Sun is a star.
  • Its vital statistics are: it’s 4.6 billion years old (about middle aged as far as the lifespan of stars go) and weighs a mass of 2 x 1027 tonnes.
  • About 74% of the Sun is hydrogen. 24% is helium. The rest consists of trace amounts of iron, nickel, oxygen, and all other elements. 
  • The solar system consists of the Sun and eight planets, but the Sun pretty much makes the solar system. It accounts for 99.8% of the total mass of the solar system, most of the remaining 0.2% comes from Jupiter.
    Earth and the rest of the planets together make up just a fraction of the solar system’s mass.
  • The temperature of the Sun’s atmosphere reaches about 100,000°C. The temperature at the Sun’s surface, the photosphere, is less at about 6,000°C, but increases as we move inwards towards the Sun’s, which measures about 15 million degrees Celsius!
  • Ultraviolet light from the Sun has antiseptic properties and is used by industries to sanitize tools and water. In our bodies, it helps in the production of vitamin D. However, UV Rays also cause sunburn.

Eclipse from another world

29 June, 2009

Another planet to be exact.

When our Moon, Earth’s only satellite, blocks our view of the Sun, it gives us a solar eclipse. But what about the moon or moons on the other planets in out solar system?

Mars (the fourth planet from the sun, not the candy bar) has two natural moons, Phobos and Deimos.

To recap, a transit happens when an object that appears visually smaller passes in front of an object that appears visually larger.

Image: NASA

And this is what happens when Phobos passes between the Sun and Mars.

The transit only lasts 30 seconds or so due to the very rapid orbital period of 7.6 hours. Which means if you were standing on the surface of Mars, you would see a shadow glide across the disc of the Sun quite rapidly.

Because Phobos’ orbit is close to Mars and in line with its equator, transits of Phobos across the Sun occur somewhere on the Red Planet on most days of the Martian year.

Thanks to the Mars Rover Opportunity, we get to witness a “solar eclipse” from Mars — Phobos transiting the Sun.

As for Mar’s other moon, Deimos, it also transits the Sun when it passes between the Sun and Mars. Deimos has a relatively rapid orbital period of 30.3 hours, and a transit lasts a maximum of about 2 minutes.

Image: NASAAlso taken by the Mars Rover (isn’t technology simply wonderful), this is what a transit of the moon Deimos across the Sun would look like if you were on Mars.

Eclipse over Africa

29 June, 2009

Here’s a sequence shot of the June 21, 2001 eclipse, a total solar eclipse of the Sun with a magnitude of 1.0495, visible from a narrow corridor in the southern Atlantic Ocean and southern Africa, in this case, over Zimbabwe.


Starting at the upper left, this sequence of images follows the progress of the magnificent 21 June, 2001 solar eclipse in the clear skies over Bakasa, Zimbabwe. These pictures were recorded using a small reflecting telescope and digital camera with the approximate local time given above each frame. A simple pair of “eclipse spectacles” were mounted as a filter in front of the telescope mirror and removed during totality. In the early and late phases of this eclipse of the active Sun, sunspot groups can be seen lingering on the solar surfaceDuring eclipse totality, pinkish prominences are visible at the solar limb along with details of the normally hidden solar corona. Seen from this location, the total eclipse phase lasted just under 3 1/2 minutes as the Moon’s shadow rushed across northern Zimbabwe at nearly 5,000 kilometers per hour.

Source: Astronomy Picture of the Day

Astronomy Picture of the Day, Solar Eclipse Picture of the Century

24 June, 2009

Another rare sight of a rare sight. A solar eclipse seen from the ends of the earth, in Antarctica. It was taken by Fred Bruenjes ( The description that goes with this picture is as follows:

The Sun, the Moon, Antarctica, and two photographers all lined up in 2003 Antarctica during an unusual total eclipse of the Sun. Even given the extreme location, a group of enthusiastic eclipse chasers ventured near the bottom of the world to experience the surreal momentary disappearance of the Sun behind the Moon. One of the treasures collected was the above picture — a composite of four separate images digitally combined to realistically simulate how the adaptive human eye saw the eclipse. As the image was taken, both the Moon and the Sun peaked together over an Antarctic ridge. In the sudden darkness, the magnificent corona of the Sun became visible around the Moon. Quite by accident, another photographer was caught in one of the images checking his video camera. Visible to his left are an equipment bag and a collapsible chair.

Absolutely amazing.

Photo: Fred Bruenjes (

Astronomy Picture of the Day is an excellent website that features a different image or photograph of our fascinating universe every day, along with a brief explanation written by a professional astronomer.

Google’s led me there more than once when I’m doing searches, so it must have quite a few fans out there (which means I’m not the only geek around). Some pictures are incredible. Do a search or go to the index and pick your favourite heavenly body: galaxies, nebulas, planets, and, of course, solar eclipses.

This solar eclipse occurred on November 23, 2003 and fell along a corridor in the Antarctic region, though the southern tip of South America and most of Australia caught a partial eclipse.

Source: Astronomy Picture of the Day

The eclipse of March 29, 2006

19 June, 2009

Check out this wonderful video of the March 29, 2006 total solar eclipse. It was visible from a narrow corridor that traversed half the Earth.

The path of totality of this eclipse began in Brazil and extended across the Atlantic to Africa, across Ghana, Togo, Benin, Nigeria, Biger, Chad, Libya and a corner of Egypt. It travelled across the Mediterranean Sea to Greece and Turkey, before crossing the Black Sea via Georgia, Russia and Kazakhstan.


Space Shuttle to Earth, via Twitter

11 June, 2009

TwitterThe STS-125 joined the realm of social networking and micro-blogging as astronaut Michael J. Massimino used Twitter not just to document the training and preparations for the mission, he sent Tweets from space. Followers on Twitters could read status updates of what astronauts were doing, from every space walk to what meals they were having. It was bringing space travel to the masses like never before.

The first Tweet sent from space read:

“From orbit: Launch was awesome!! I am feeling great, working hard, & enjoying the magnificent views, the adventure of a lifetime has begun!”

We couldn’t have said it better.

Follow future missions and other NASA activities on Twitter here (the Space Shuttle Endeavour is scheduled to launch this Saturday on STS-127 to the International Space Station).

Then follow us on Twitter here.