Monthly Archives: June 2009

There’s a Rumor About Mars…

Are Mars & Earth an item?

Are Mars & Earth an item?

Whoa snap!  Rumors are swirling!  Word on the street is that red-hot Mars and cool-cat Earth have been getting closer…. but are the rumors true?  And is red the new black?  Chuck Abuck at Planet Magazine cuts through the hype with an exclusive interview with Mars himself!    [1:40m]

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What’s the facts?

Sorry folks, the rumors are false.  Every year around August emails circulate about the impending close approach of Mars, when it will appear to be “as large as the Moon in the sky.”  It is true that in August 2003 Mars did have its closest approach to Earth in about 60,000 years, passing within 56 million kilometers (35 million miles) of our planet.  This made Mars slightly larger and brighter than usual, but nowhere near the size or brightness of the Moon, which is only 380,000 kilometers (235,000 miles) away.    For some reason, this event is reported as happening every year, but really, it was soooo 2003.

Original air date 23 June 2009.

Happy Birthday Universe!

The Universe is looking great for its age

The Universe is looking great for its age

Happy birthday Universe!  Unfortunately, its hard to see the cake beneath all 13.7 billion candles… [0:24m]

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What’s the facts?

Yes, we actually know the age of our Universe!  But how do we know?  One helpful clue is that our Universe is expanding.  We see this from the fact that distant galaxies in all directions are moving away from us, and the most distant galaxies are moving the fastest.  Trace back all that motion to one point in space and time – the Big Bang – and you can figure out how long the Universe has been around.  However, this type of age estimate makes an assumption as to how the Universe formed and how the expansion rate has changed over time – in astronomer-speak, it’s a “model-dependent” age.  But other direct age estimates, such as the radioactive decay of heavy elements and the ages of the oldest stars and star clusters, give similar numbers.  Astronomers now estimate that the Universe is  13,700,000,000 years old – now that’s a birthday cake!

Original air date 4 April 2009.

Light as Distance

I am a ruler

I am a ruler

Did you know you can use light as a yardstick?   Charae and Professor B calculate how long it takes light to get from the Sun to the Earth, and discover that they are sitting only one light-nanosecond from each other! [2:00m]

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What’s the facts?

The speed of light is 300,000 kilometers per second, or 186,000 miles per second, and it’s a constant in the Universe.  This makes it handy for switching between measures of time and measures of distance.  For example, we can calculate how long it takes for light from the Sun to reach us, by dividing the distance between the Sun and the Earth – 150 million kilometers (93 million miles) – by the speed of light; it’s a bit over 8 minutes.  We can also measure distances by multiplying the speed of light by a time.  Astronomers commonly use the light-year, the distance light travels in a year, to measure the distances to stars.  One light-year is equal to 9.5 million million kilometers, or 6,000,000,000,000 miles – whew!  For distances closer to home, a light-nanosecond – which is about a foot – is a little more useful.

Original air date 28 March 2009.

Camp Shalbatana!

Will they have kayaks?

Will they have kayaks?

Makena’s packing for Martian summer camp at Lake Shalbatana Vallis, and mom’s being a little too overprotective…  [1:35m]

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What’s the facts?

On June 17, 2009, astronomers at the University of Colorado at Boulder announced that they had found definitive evidence of lake shorelines in a deep valley on Mars called Shalbatana Vallis.  Using photographs from a high resolution camera aboard a spacecraft called the Mars Reconnaissance Orbiter (currently orbiting around Mars), the astronomers found formations similar to river deltas.  They did not actually find a lake, however; that probably dried up about 3.5 billion years ago (that’s 3,500,000,000 years ago!).  So don’t bother bringing your swimsuit.  Finding evidence of a past lake is nevertheless important as it suggests that Mars may have been warm and wet billions of years ago, and as such could have supported life.

Original air date 19 June 2009.

Do you have Phobos Phobia?

Don't Panic!

Don't Panic!

Do you have an irrational and overwhelming fear of Phobos smashing into Mars? You may not be alone… [0:25m]

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What’s the facts?

Phobos is one of two irregularly shaped moons in orbit around Mars; the other is named Deimos.  Phobos orbits once every 7 1/2 hours around Mars at a height of only 9377 kilometers (about 5800 miles) above the surface of Mars. In comparison, the Moon orbits once every 27 days at a height of 385,000 kilometers (about 239,000 miles).  So Phobos is 40 times closer to Mars than the Moon is to the Earth, which might make a Martian claustrophobic!  Incidentally, the name Phobos comes from the Greek god of fear!

Original air date 19 June 2009.

Intergalactic Weather Channel: It’s Cold on Pluto

Folks aren't happy out on Pluto these days

Folks aren't happy out on Pluto these days

Intergalactic Weather Channel’s Trisha Takanawa and disgruntled reporter Jake Jacobs bring you weather conditions from distant dwarf planet Pluto.  Seems like Jake has a chip on his shoulder about this assignment. [1:21m]

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What’s the facts?

Tiny Pluto is one of our most far-flung worlds, orbiting at a distance of between 4.4 billion and 7.3 billion kilometers (2.7 billion to 4.5 billion miles) from the Sun.  Because it is so far away, Pluto receives a small fraction – only 0.04% – of the Sun’s radiation as compared to what we get here on Earth.  As a result, the surface of Pluto gets down to a chilly -240 degrees Celsuis (-400 degrees Farenheit).  It is so cold that Pluto’s thin atmosphere, made mostly of the gases nitrogen and methane,  almost completely freezes out in the winter.  The great distance of Pluto from the Sun also means its pretty dark there, so it’s important to keep track of your flashlight!

Original air date 23 June 2009.

Intergalactic Weather Channel: It’s Stormy on Jupiter

Expect stormy conditions on Jupiter

Expect stormy conditions on Jupiter

Intergalactic Weather Channel’s Trisha Takanawa and spot reporter Shaine Laine give us the latest conditions in the Great Red Spot on Jupiter – be sure to bring your umbrella! [1:20m]

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What’s the facts?

The Great Red Spot is a massive hurricane-like storm in the upper atmosphere of Jupiter, currently measuring about 24,000 kilometers (15,000 miles) across and 12,000 kilometers (7,500 miles) tall.  About two Earths would fit nice and snug inside.  The Great Red Spot was first seen by Robert Hooke and Giovanni Cassini back in 1664-1665, and has been slowly shrinking over the past century, now about half the width it was in 1900.  The winds in the Great Red Spot are greatest around its edge, about 430 kilometers per hour (260 miles per hour), larger than a Category 5 hurricane on Earth.  In 2000-2006, three smaller, white storms just below the Great Red Spot merged and turned into a single red storm called “Red Spot, Jr.” (scientists call it Oval BA), which is now about the size of Earth.  Why these storms appear red remains a mystery!

Original air date 23 June 2009.