Fall is here

The weather here today, and for the next three or four days is indicative of what fall is like in this area. The sky is grey, and the rain is coming down. In anticipation of that, yesterday I went up on the roof to make sure that the downpipes are clear of debris and that the roof was ok.

Oh, the joys of Fall.
Derek and his family have taken a minivacation in Victoria over the weekend - we're glad that he's feeling well enough to do that. They are staying at a nice hotel - swimming pool and other amenities - a little "pretend summer". We'll "veg out" here today; no point in getting dressed. The granddaughters' fish need their daily feeding - we are looking after that. After all, what are grandparents for?

Summer's goodbye

You know that summer has passed when it's time to reel in all the hoses and to stow away the sun umbrella and the plastic chairs, the outdoor table, and the other paraphenalia which are part of maintaining and enjoying your garden and lawn. So, this we did during the last couple of days.

It's time to "hunker down" for the colder days ahead - no more outdoor garden dinners or picnics for this year. Maybe we'll get some days with some sunshine during which sitting on the (covered) back porch will give us the illusion of summer.

This year seems to be passing exceptionally quickly in some ways, and yet it also seems to be endless in some others. Derek's fight with cancer certainly contributes to the latter impression.

Who stole them?

Today is one of the typical fall days that are common in our area during this time of year. Here are two pictures taken from our living room window comparing a nice, sunny late fall day of last year to today. Somebody seems to have stolen the mountains.

Today














Last year












Our Mexican guests left yesterday; it seems as though they took the nice weather with them.

People

We have guests from Mexico at our place right now, and this means a lot more social activity, of course. We all enjoy home cooking, and we also sit around in the evening for a "happy hour". All of us here are members of an informal international group of friends, who travel and meet at various spots in the world.

Tonight, we've invited Derek and family to dinner here, and I anticipate lively discussions, along with the excellent food, which one of our friends, who is a professional chef and runs his own small hotel in Mexico, is in the middle of preparing.

As you get older (as I am), you understand more and more that we humans are social animals, and that being alone is one of the worst situations in which you can find yourself. So, hug and talk to friends and family, and especially the children - we all appreciate companionship and caring.

Home attention.

As an owner of a house, you're always aware that it requires ongoing maintenance. It was time again for some of that this weekend. I replaced four door locks, the garden needs attention - trimming of hedges, bushes (a couple of dead ones were removed), and trees; some replacement planting is also necessary. This is work in progress. Derek's family is painting some rooms; there's always something that needs looking at.

You may have read Dereks' blog, but, if you haven't, I recommend you do. He has posted a link to his video appearance at the Seattle Gnomedex - I'm sure you'll find it interesting.

Cassini marvels

I have mentioned the amazingly successful probe Cassini, which is orbiting the planet Saturn, before. It recently passed very closely by one of Saturn's moons, called Iapetus. This moon can be seen with a telescope from Earth, as a tiny spot of light. It has the strange characteristic of appearing about five times brighter when we see it on one side of Saturn then when it is on the other side. This is caused by the unique fact that Iapetus appears to be "coated" with a very dark layer of dust on the "leading" hemisphere. That's the part of the moon which always faces "head-on" into the direction of its travel around Saturn. Iapetus has "captured rotation" with respect to Saturn, the same side of Iapetus faces Saturn, as this moon orbits it (this is true of our Moon as well, we never see the Moon's far side from Earth). Therefore, these moons (and others in the solar system) always rotate once in exactly the same time as they complete one orbit around their "mother planet", and the same part of the moon's surface is always "facing forward".

Another amazing aspect of Iapetus is the enigmatic mountain range which circles the entire moon at exactly its equator. These mountains exceed the height of the Himalayas on Earth. In the above picture, they can be seen clearly. It's almost as though the two halves of this moon were "slammed together" at one time. We have no good explanation for this phenomenon.

The flyby on September 10 of this year produced some amazing images, among which is one showing a closeup of the "equatorial bulge" , and the other showing blindingly white, snowlike, "uncoated" part of the bright surface of Iapetus. I have reproduced them below.

Below is a quote by NASA:

Saturn's Moon Iapetus is the Yin-and-Yang of the Solar System - September 12, 2007 (Source: NASA/JPL/Space Science Institute)

This close-up view shows mountainous terrain that reaches about 10 kilometers (6 miles) high along the unique equatorial ridge of Iapetus.

PASADENA, Calif. -- Scientists on the Cassini mission to Saturn are poring through hundreds of images returned from the Sept. 10 flyby of Saturn's two-toned moon Iapetus. Pictures returned late Tuesday and early Wednesday show the moon's yin and yang -- a white hemisphere resembling snow, and the other as black as tar. Images show a surface that is heavily cratered, along with the mountain ridge that runs along the moon's equator. Many of the close-up observations focused on studying the strange 20-kilometer high (12 mile) mountain ridge that gives the moon a walnut-shaped appearance."The images are really stunning," said Tilmann Denk, Cassini imaging scientist at the Free University in Berlin, Germany, who was responsible for the imaging observation planning. "Every new picture contained its own charm. I was most pleased about the images showing huge mountains rising over the horizon. I knew about this scenic viewing opportunity for more than seven years, and now the real images suddenly materialized."This flyby was nearly 100 times closer to Iapetus than Cassini's 2004 flyby, bringing the spacecraft to about 1,640 kilometers (1,000 miles) from the surface. The moon's irregular walnut shape, the mountain ridge that lies almost directly on the equator and Iapetus' brightness contrast are among the key mysteries scientists are trying to solve.

This image shows terrain in the transition region between the moon's dark leading hemisphere and its bright trailing hemisphere.
"There's never a dull moment on this mission," said Bob Mitchell, Cassini program manager, NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We are very excited about the stunning images being returned. There's plenty here to keep many scientists busy for many years." "Our flight over the surface of Iapetus was like a non-stop free fall, down the rabbit hole, directly into Wonderland! Very few places in our solar system are more bizarre than the patchwork of pitch dark and snowy bright we've seen on this moon," said Carolyn Porco, Cassini imaging team leader at the Space Science Institute, Boulder, Colo. The return of images and other data was delayed early Tuesday due to a galactic cosmic ray hit which put the spacecraft into a precautionary state called safe mode. This occurred after the spacecraft had placed all of the flyby data on its data recorders and during the first few minutes after it began sending the data home. The data flow resumed later that day and concluded on Wednesday. The spacecraft is operating normally and its instruments are expected to return to normal operations in a few days. "Iapetus provides us a window back in time, to the formation of the planets over four billion years ago. Since then its icy crust has been cold and stiff, preserving this ancient surface for our study," said Torrence Johnson, Cassini imaging team member at JPL. Cassini's multiple observations of Iapetus will help to characterize the chemical composition of the surface; look for evidence of a faint atmosphere or erupting gas plumes; and map the nighttime temperature of the surface. These and other results will be analyzed in the weeks to come. Iapetus flyby images are available at: http://saturn.jpl.nasa.gov/ and http://www.nasa.gov/cassini and http://ciclops.org/.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo. RELATED MULTIMEDIA: Video file with animation, images and sound bites will air tomorrow on NASA TV. Contacts:Carolina Martinez 818-354-9382Jet Propulsion Laboratory, Pasadena, Calif. Preston Dyches 720-974-5859Space Science Institute, Boulder, Colo.

Binoculars and the Moon

Next Saturday, September 15, the Moon will be approximately of the shape shown in this picture. Assuming that you happen to have a clear sky that evening, you should be able to view the Moon as described:

If you have access to a pair of binoculars, and, preferably, can support them by some means to hold them steady (a phototripod, perhaps), you can see the craters and the dark areas similar to what's shown here. It's surprising what a pair of binoculars can do. Galileo Galilei (15 February 1564 – 8 January 1642) would have given his eye teeth for optical performance like this when he was alive.

The most prominent of the dark areas is the round area near the upper right of the centre of this picture. It's called "Mare Criseum" - the Sea of Crises - and can be seen with the naked eye. It's an old impact area, of about 400km diameter. The dark material is thought to be ancient lava which erupted from the Moon when a fair-sized asteroid hit it a few billion years ago. From Earth, it looks slightly oval, but this a "perspective" effect. It is actually quite circular.

This picture was taken at the prime focus of a Celestron C-8 telescope (equal to a 2000mm lens at f10) at 1/200sec exposure with a Canon Rebel XT digital SLR camera.









Here's a closer view of Mare Criseum.

How far can you see?

Are you interested in the stars (I don't mean Hollywood's superficial celebreties)? Have you ever wondered how far away they are? Do you think you need a lot of fancy equipment to see anything meaningful in the sky? Well, despair not, you too can be an "astronomer", and all you need is your eyes (and a clear sky).

The picture you see here is a simulation of a section of the nighttime sky as it appears at about 11pm at this time of year (created by a planetarium program called Starry Night Pro Plus, available at http://www.imaginova.com/). Click on the picture to see it enlarged. If you step outside at around that time of night and look up straight overhead, you'll see at least the three brightest stars shown here. They are labelled Vega, Deneb, and Altair. You can draw some imaginary lines between the three to form what's known as the "Summer Triangle", most readily seen in the summer and fall months.

All three stars are a lot bigger than our own sun, and, although they appear to be of similar brightness, they are located at vastly different distances from us. Vega, the brightest, is located at a distance of about 25 light years, Altair is about 17 light years away, and Deneb can be found at a distance of about 1,500 light years.

This begs a question. What, exactly, is a light year? The first thing to realize is that it represents a distance. How is that defined? Well, a light year is the distance that light travels in one year. The speed of light has been measured very accurately, it's just about 300,000km per SECOND. This means that light can travel around the Earth (circumference 40,000km) more than 7 times per second. There are about 31.5 million seconds in a year - so the distance of one light year is 31.5 million times 300,000km; it's a tremendous stretch. You do the math.

Since Deneb is 1,500 light years away, it took light 1,500 years to cover that distance. When the light we see now left Deneb, the holy Roman empire had just about disintegrated, and we were beginning to enter what has been called a cultural wasteland: the "dark ages". Similarly, the light which left Altair and Vega has travelled for the same number of years as they are distant (measured in light years, again). It's hard to imagine that Deneb is almost 100 times farther away than Altair, yet they appear almost equally as bright from Earth. What a tremendous difference exists between individual stars. We'd be fried instantly, if Vega were located as close to us as our own sun.

You can see that when you look at the stars, you are also looking backward in time. For all we know, these stars may have exploded by now (a common occurrance for huge stars); we won't know that until 25, 17, or 1,500 years from now, respectively.

What were you doing at the time the light left the stars mentioned?

You can understand the sky without any special equipment - you can see things that are a long way off. Your eyes and an open mind are all that's required. To really appreciate the grandeur of the universe, though, you ought to find a truly dark sky - a location away from the pervasive light pollution which wipes out all the faint stars in our cities.

Classics

When the weather is nice, many people exhibit treasures which they would not want exposed to rain. One such category is that of classic cars. Beautifully maintained, they hark back to an age when driving was courteous, considerate, and far less aggressive. Some have lines that would be a wonderful fit for today's high tech wonders, others reflect the society of yore. In short, they're "classic". We thought that we should have a look at these - there is an "old car" show on in town at the moment.

My wife and I fit right in. Those years in which these beauties were manufactured were our "young" years, and I think that the pleasure of driving was far more appreciated then. We certainly had our (usually clean) fun, and were perhaps more aware then today's young folks regarding the responsibilities of being in charge of these big machines. Be that as it may, our generation is likely to be considered as "backward" as these vehicles; our internal "guts" probably work with the same degree of efficiency. We need as much or more ongoing maintenance - we're "classic", too.