Category Archives: Mercury

'Casts, Jupiter, Mars, Mercury, saturn, venus

Awesomeness

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Celebrate It

I just read somewhere that March 10th is the International Day of Awesomeness.  It’s probably not an official government holiday or anything, but seems to exist to celebrate all things awesome.  So, what could be more awesome than the starry sky?  Living where I do (high in the mountains) with reasonably clear skies on many nights, I can step outside and look up and grok the awesomeness of the stars. And, this past week or so — and into March — the awe-inspiring sight of the planets Venus, Jupiter and Mercury just after sunset.  Mars is rising in the East, and if you wait a few more hours, you can see Saturn rising very late in the evening.  If you have binoculars or some kind of telescope, so much the better. You can check out Jupiter’s moons, for example. Or, if our own Moon is up, you can scan its cratered surface.  That’s the kind of astronomy awesomeness that gets people hooked on stargazing for life.

Speaking of telescopes, I know that people have a lot of preconceptions and misconceptions about ‘scopes.  When I worked at Sky & Telescope, we regularly answered questions in our magazines about the “best” scope to buy, the “most economical” and so on. Truth is, what you buy depends on what you want to look at, or if you’re planning to do astrophotography. Or, if you just want something you can easily pick up and take outside.  That’s where binoculars come in handy, and I’ve always recommended people start out with a pair of 10x50s as a good choice.  But, telescopes can give you awesome views, too.  I’d recommend you peruse Sky&Telescope.com or Astronomy.com for some good advice there.

The Galileoscope. Courtesy Galileoscope.org.

A former colleague from Sky & Telescope got involved a few years ago in a cool project called the Galileoscope. It was originally created to help celebrate the Interational Year of Astronomy in 2009. The Galileoscope is a small, build-it-yourself telescope that thousands and thousands of people have constructed and used to look at the sky. It’s a perfect way to introduce children to the sky and the instruments we use to observe it with.  You can learn more about the Galileoscope here, including where it can be purchased.  By the way, if any readers work in or run planetarium or science center gift shops, there are special discounts for bulk purchases to sell in gift shops. Check it out!  It’s awesome in its own right and worthy of celebration!

I mentioned above about how the planets are lining up for some gorgeous views in the next few weeks.  In fact, I focus on those views in the latest installment of Our Night Sky, the monthly stargazing program I produce for Astrocast.TV.  So, if you’re into some planetary viewing awesomeness, check it out. It’s about four  minutes long, and along with the planets, we look at a few constellations and a couple of deep-sky objects. It’s enough to get you started on some awe-inspiring sightseeing through the cosmos!

 

 

Mercury, MESSENGER

Mercury’s Swift MESSENGER

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Exploring a Hot/Cold Little World

This WAC image showing a never-before-imaged area of Mercury’s surface was taken from an altitude of ~450 km (280 miles) above the planet during the spacecraft’s first orbit with the camera in operation. The area is covered in secondary craters made by an impact outside of the field of view. Some of the secondary craters are oriented in chain-like formations. Courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.

Yesterday was a banner day for the folks who run the MESSENGER mission to Mercury.  The first images that the spacecraft has taken since it achieved orbit around the planet began streaming back to Earth.  Now, there have been a good many flyby images of Mercury, not all of them high-res, since we began exploring the solar system in the mid-1960s with spacecraft. But, these are the first taken from a spacecraft orbiting the planet.  This means that we’re going to (finally) get to see every bit of this world’s ancient, cracked and cratered surface.

The first images (which you can browse at the MESSENGER Web Site) are pretty detailed.  For example, this Wide Angle Camera view shows an area near the north pole of the planet.  It was taken as the spacecraft made its closest approach to the sunlit side of the surface.  The long shadows are caused because the Sun is at an oblique angle to the spacecraft, which was just about to cross over into darkness.

The polar region of the planet is of great interest to astronomers because some radar studies of the area taken from Earth seem to imply that there might be ice on the walls of those craters. Sunlight never penetrates into the craters, so that would be an exciting cache to study someday.  The water could be from impacts of comets, and studying THAT ice would tell us about the compositions of the comets that left their water behind.

The full imaging mission, which is planned to last for at least a year, begins on April 4; currently scientists and engineers are testing the spacecrafts systems and instruments to see how it is responding to its permanent home in orbit around Mercury — and enduring the harsh environment so close to the Sun.

Mercury might seem the last place you’d want to visit — and it probably won’t be the subject of human exploration for a long time. It’s a pretty extreme place, experiencing the widest surface temperature swings of any place in the solar system. It has little to no atmosphere, and its surface takes a radiation pounding from the Sun. Still, if you’re going to completely understand the solar system you inhabit, it pays to study the extreme places as well as the temperate (relatively) ones. In Mercury’s case, astronomers have a very specific set of questions to ask to help understand this place:

Why is Mercury so dense?  What is its geologic history? What is the nature of its magnetic field? What is the structure of the planet’s core? What are the unusual materials seen at the poles?  What volatiles (gases) are important at Mercury?

Some of these questions are those you’d ask at any planet to help you understand its composition and history.  So, with Mercury, we’ll finally get some closure on the last of the major planets of the solar system.  The only remaining world to visit (and there’s a spacecraft on the way) is dwarf planet Pluto. New Horizons will give it a swing-by in 2015, on its way out to explore the outer solar system. Another extreme, to be sure, but now we’ve got precedent with Mercury.