Astro Bob blog: 'Til death do us partThoughts on life's joys and end plus reflections on reflections
By: Bob King, Duluth News Tribune
'Til death do us part
The moon joins several bright stars and the planet Mars tonight and tomorrow night as it waxes toward gibbous phase and moves eastward. This map shows the sky around 9 o'clock. Created with Stellarium
My wife Linda has read the obituaries in the newspaper for years but I've always avoided them until recently. I wrongly assumed they were mainly lists of kin and funeral dates, but she pointed their sweet side to me and now I've started to read them occasionally. Many of the "obits" make reference to what the person loved in life. When you read them, you realize that all these people had passions like our own. Linda kidded me one evening that my obit would read how "he loved to announce the temperature" and that I was the "town crier of temperatures." Apparently I get excited when the temperature hits an extreme high or low for the day. Never knew it made such a strong impression.
I thought I'd share a few excerpts from recent obituaries with you since I know we share a similar passion, the stars. My wish is to pass away on a cloudy night (wouldn't want to miss a clear sky opportunity) and besides having the temperature at the time of death etched on my gravestone, be remembered for "the unabiding joy he found in the night sky and in telling bad puns."
Although they bring the inevitability of death to the fore, the obits have their bright side, too. Each of these people found something in life to fall in love with. I do believe that's our purpose on Earth.
The following all appeared recently in the Duluth News Tribune:
-- Anne Paine Williams, 77: "Anne loved all creatures great and small. She once successfully administered CPR to a drowning chipmunk, which then became her "friend."
-- George Montgomery, 94: "George enjoyed fishing, card games, motorcycle riding, snowmobiling and camping with his family and friends."
-- Elaine Onraet, 77: "She was an avid knitter for family and friends. She also enjoyed watching and contributing to PBS."
-- Martha Whittaker Josephson, 91: "At the time of her death she was still reading two to three book a month; watching "Jeopardy" and dining on tilapia once a month at the Olive Garden."
-- Aline Vidor, 96: "She loved to walk, and would do so on her routine regardless of weather conditions."
-- Charlotte Rahja, 89: Charlotte was well-known for her quick wit, love of dancing, Twins baseball and stock car racing.
--Gerald Chell, 52: "Gerry enjoyed fishing, carving, painting and having coffee with his brother Merlin."
-- Edna Verdugo, 81: "... will be remembered for her kindness, thoughtfulness, love, witty sense of humor and a great cup of tea."
I built a fire in the backyard last night and watched the moon come out of the clouds, a scene half firelight, half moonlight. Appearances to the contrary, the moon is a dark body, reflecting just 12 percent of the sun's light on average. The rest is absorbed by the surface. For comparison, a worn asphalt parking lot's reflectivity is 12 percent and charcoal is four percent. The main reason for the moon's apparent brilliance is its contrast with the dark sky in addition to our eyes being more sensitive to faint light at night.
A typical parking lot and the moon both reflect about the same amount of light which is another way of saying the moon is only as bright as worn asphalt. Photos: Justin Hayworth (left) and Bob King.
The astronomical term for the amount of light a body reflects back into space from a light source like the sun is albedo (al-BEE-doh). The darkest objects have albedos near zero, the brightest are 1.0. Venus is the brightest planet and has an albedo of 0.65, meaning it reflects back 65 percent of the sunlight it receives. Perpetual cloud cover is main reason for Venus' brilliance. Earth's albedo is 0.37 while Mercury and Mars are the darkest planets with albedos of 0.11 and 0.15 respectively. One of the brightest objects in the solar system is Saturn's moon Enceladus (en-SELL-uh-dus) which reflects 99 percent of the sun's light. Being made of ice makes you very reflective indeed. At the other extreme, the cores or nuclei of comets have albedos that are typically the same as charcoal.
Astronomers can determine all sorts of interesting information about an object's surface properties by studying how its albedo varies as it rotates or goes through phases like the moon. Low albedos can indicate dark, carbon-rich surfaces similar to the carbonaceous meteorites we've studied here on Earth. High albedos can point to ice while high "radar" albedos indicate high metal content in asteroids.
All good things to reflect upon while watching the albedo of my bonfire slowly diminish from 0.3 to 0.1.