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.

Grandparents' joys

One of the joys and privileges of being grandparents is that you are allowed to spoil your grandchildren, and have fun doing it. Therefore, we took advantage of the fine weather today and invited our granddaughters Marina and Lauren to our annual, local fair, called the Pacific National Exhibition. Perhaps saying that our granddaughters intimated that an invitation would not be resisted approaches the truth even more closely.

The PNE started about a century ago as an agricultural fair, with a small amusement park (Playland) on the side. Well, Playland has become the main reason why people attend it; Marina and Lauren naturally came for the same reasons - the rides and games.

One of the cultural parts of the exhibition outside Playland was really classy - the acrobats from China were amazing. We all enjoyed that.

Of course this also became a "junk food day" - every now and then you have to forget about the restrictions you face as a senior.

As grandparents, we had a lot of fun watching the granddaughters screaming their way through the many rides they went on. It also brought back memories of our own "young" PNE days.




This was very much a fun (and exhausting) day.

Surprising interest

Over the years, I've participated in many a public astronomy night, where we we would take our telescopes and set up for public viewing. Invariably, everyone attending was impressed, sometimes awestruck, often incredulous as to the things one can see through a telescope. In my mind, the people who show up at these events always have a keen interest in astronomy, and they know it. They make the effort to come. Conversely, I thought until now that people who didn't show did not have that kind of curiosity, or didn't think of it as being important, if they had heard about the event.

Since I started my blog just a little over a month ago, I think that there are not many readers of it around. Considering that, a fair percentage of comments come back to me. To my surprise, my post about the recent lunar eclipse brought some responses which make me think that many people would like to know more about what can be seen "up there", without having any specialist knowledge in that regard.

There are some easy ways to do these things yourself - without any special equipment. Naked-eye astronomy, astronomy using binoculars, basic cameras.... one can do a lot in that regard. If there is enough interest, I can occasionally do a post about this.

The Moon hiding

This is the setup used for the eclipse pictures shown below. There was a constant, varying haze in the sky, necessitating some exprimenting with exposure times. The final phases were not captured, because solid clouds obscured the Moon in the end.


















As mentioned before, this morning a total eclipse of the Moon occurred. I woke up just in time to witness and photograph the event. The above image shows the Moon just disappearing into the Earth's shadow.


This shows the Moon when it had moved well into the Earth's shadow:




The orange tint is the result of the sunlight refracted around the Earth. As seen from the Moon, the Earth would seem to be surrounded by a "ring of fire" of this orange colour. It's like a sunset, except as seen from far away in space, with the whole Earth blocking the Sun.









The Moon is now at midpoint of the total eclipse:





Taken with a Canon Rebel XT through a Celestron C90 telescope at f11 (= a 1000mm focal length telephoto lens - see top image) and an exposure time of 3.2 seconds, sensitivity at 800 ASA.

Added on Aug 31:
You'll notice that the Moon does not appear quite sharp in one direction here. The cause is the Earth's rotation.

There is a faint image of a star streak close to the left edge of the image. The length of this streak tells you how much the image shifted due to this motion during the 3.2 seconds. If I had used my "equatorial" mount, and attached the telescope and camera to it, there would have been no "smear"; that type of mount compensates for the rotation, and is used for those astronomical photos which require many minutes or hours of exposure time.


Leaving the Earth's shadow:
f11 at 1/20 sec
















f11 at 1/160 sec

Eclipse of the Moon

On the morning of August 28, 2007, the full Moon will move through the Earth's shadow. This event is not rare, it is the second such event this year. This one, however, takes place at a time when the Moon is above the horizon for North and South America, the Pacific Ocean, and countries around the Pacific Rim. While the eclipse can be seen from beginning to end in the Pacific Ocean and the West coast of North America, the remainder of the locations mentioned above will at least see a part of it, while some of it occurs after the Moon sets (Eastern North America, all of South America), or before the Moon rises (Eastern Asia, Western Australia).

The various phenomena that occur on the Moon are seen simultaneously in all areas mentioned; the various locations have their own local time, of course. There is a worldwide standard time called Universal Time (UT), which is used to relate all world-wide phenomena and activities. For instance, the computer systems in the financial world have to be based on this time reference, in order to maintain the relationships of financial transactions. Other uses for an agreed-upon, common time reference are found in transportation and travel scheduling, this common reference is of importance to us here, in science, too - astronomy in this case. So here is the UT sequence of events for this Lunar Eclipse:

Penumbral eclipse begins (the first imperceptible darkening of the Moon) 7:53:39 UT
Partial eclipse begins (the main Earth shadow begins to cover the Moon) 8:51:16 UT
Total eclipse begins 9:52:22 UT
Greatest eclipse 10:37:22 UT
Total eclipse ends 11:22:24 UT
Partial eclipse ends 12:23:30 UT
Penumbral eclipse ends 13:21:01 UT

(all times taken from the Observers' Handbook of the Royal Astronomical Society of Canada, Toronto, Ontario, Canada)

UT is sometimes stated as Greenwich Mean Time (GMT). The various locations on Earth have their local time assigned based on their geographical "time zones". For North America, these time zones are 4 to 8 hours (East to West) "behind" UT. For instance, the Greatest eclipse for the West coast of North America, stated in Pacific Standard Time (PST) is 10:37:22 UT - 8 = 2:37:22 PST. An added complication is the use of daylight saving time. This adds an hour to the Standard Time in each time zone. So, for the above example, the Greatest eclipse occurs at 3:37:22 in the morning.

This event requires no telescope - the naked eye does a great job here. Any pair of binoculars will enhance the experience; in fact, for me, binoculars are the preferred means by which to view this event. Photography is relatively easy, but use a tripod and your optical zoom or zoom lenses to their maximum extent. The Moon appears surprisingly small in pictures taken with standard focal length lenses.

For an observer on the Moon, this event would look similar to this image of the planet Saturn, as seen from the Cassini probe - minus the rings.

Galaxies collide

In 2003, a special camera telescope, named the "Spitzer" telescope, was launched to record data from faraway space in those spectral ranges which cannot be explored from inside the Earth's atmosphere. This telescope is designed to "see" images in the spectral target range from near to deep infrared.



We perceive some wavelengths of infrared as heat. Infrared light can pass more readily through dust and gas clouds. Therefore it is possible to record things which cannot be seen in visual light (red to violet).



Spitzer has been spectaculary successful and has revealed many hitherto unknown phenomena in the universe. One such is the detection of a merger of four distant galaxies. Galaxy mergers are well documented. Our own galaxy will merge with the Andromeda galaxy in about 5 billion years (I'm not buying collision insurance for that).



The merger detected by Spitzer consists of four galaxies and is located at a distance of 5 billion light years. This means it actually occurred 5 billion years ago - light has just taken that long to reach us. By now this whole assemblage is probably one big, amorphous blob.



This is the image, which is a combination of images from several different telescopes, as described in the text caption.




Here is the text caption:

NASA's Spitzer Spies Monster Galaxy Pileup
For Release: August 6, 2007



Four galaxies are slamming into each other and kicking up billions of stars in one of the largest cosmic smash-ups ever observed.

The clashing galaxies, spotted by NASA's Spitzer Space Telescope, will eventually merge into a single, behemoth galaxy up to 10 times as massive as our own Milky Way. This rare sighting provides an unprecedented look at how the most massive galaxies in the universe form.

"Most of the galaxy mergers we already knew about are like compact cars crashing together," said Kenneth Rines of the Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass. "What we have here is like four sand trucks smashing together, flinging sand everywhere."

Rines is lead author of a new paper accepted for publication in Astrophysical Journal Letters.
Collisions, or mergers, between galaxies are common in the universe. Gravity causes some galaxies that are close together to tangle and ultimately unite over a period of millions of years. Though stars in merging galaxies are tossed around like sand, they have a lot of space between them and survive the ride. Our Milky Way galaxy will team up with the Andromeda galaxy in five billion years.

Mergers between one big galaxy and several small ones, called minor mergers, are well documented. For example, one of the most elaborate known minor mergers is taking place in the Spiderweb galaxy -- a massive galaxy that is catching dozens of small ones in its "web" of gravity.

Astronomers have also witnessed "major" mergers among pairs of galaxies that are similar in size. But no major mergers between multiple hefty galaxies -- the big rigs of the galaxy world -- have been seen until now.

The new quadruple merger was discovered serendipitously during a Spitzer survey of a distant cluster of galaxies, called CL0958+4702, located nearly five billion light-years away. The infrared telescope first spotted an unusually large fan-shaped plume of light coming out of a gathering of four blob-shaped, or elliptical, galaxies. Three of the galaxies are about the size of the Milky Way, while the fourth is three times as big.

Further analysis of the plume revealed it is made up of billions of older stars flung out and abandoned in an ongoing clash. About half of the stars in the plume will later fall back into the galaxies. "When this merger is complete, this will be one of the biggest galaxies in the universe," said Rines.

The Spitzer observations also show that the new merger lacks gas. Theorists predict that massive galaxies grow in a variety of ways, including gas-rich and gas-poor mergers. In gas-rich mergers, the galaxies are soaked with gas that ignites to form new stars. Gas-poor mergers lack gas, so no new stars are formed. Spitzer found only old stars in the quadruple encounter. "The Spitzer data show that these major mergers are gas-poor, unlike most mergers we know about," said Rines. "The data also represent the best evidence that the biggest galaxies in the universe formed fairly recently through major mergers."

Some of the stars tossed out in the monstrous merger will live in isolated areas outside the borders of any galaxies. Such abandoned stars could theoretically have planets. If so, the planets' night skies would be quite different from our own, with fewer stars and more visible galaxies.

In addition to Spitzer, Rines and his team used a telescope formerly known as the Multiple Mirror Telescope and now called MMT near Tucson, Ariz., to confirm that the four galaxies are intertwined, and NASA's Chandra X-ray Observatory to weigh the mass of the giant cluster of galaxies in which the merger was discovered. Both Spitzer and a telescope known as WIYN at Kitt Peak, also near Tucson, Ariz., were used to study the plume. WIYN is named after the University of Wisconsin, Indiana University, Yale University and the National Optical Astronomy Observatory, which own and operate the telescope.

Other authors of this paper include Rose Finn of Siena College, Loudonville, N.Y.; and Alexey Vikhlinin of the Harvard-Smithsonian Center for Astrophysics.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA. Spitzer's infrared array camera was built by NASA's Goddard Space Flight Center, Greenbelt, Md. The instrument's principal investigator is Giovanni Fazio of the Harvard-Smithsonian Center for Astrophysics.

Whitney Clavin 818-354-4673Jet Propulsion Laboratory, Pasadena, Calif.

Take it when you can

We have guests from Europe at the moment and have taken the opportunity to show them around town a little. My sister and her husband invited us all to dinner yesterday, and a fine meal plus a beautiful view of the city was had by all.

Derek continues to gain strength and went to another appointment with his doctor yesterday. Nothing extraordinary needs to be done at this time, other than for him to gain some more weight. A good couple of days.