Partial Solar Eclipse

Annular Eclipse
Jan 15th, 2010 annular solar eclipse photographed from Kampala, Uganda by Dan Birchall, used by permission
May 9th will see a solar eclipse sweep across the Pacific. For viewers in Australia and the southern Pacific Ocean, this will be an annular eclipse, not a total eclipse. With the Moon near apogee and further from the Earth, its apparent size will not be quite enough to cover the entire disk of the Sun, resulting in a ring of light surrounding the silhouette of the Moon.

For viewers here in the Hawaiian islands this will be a deep partial solar eclipse, with well over 40% of the Sun obscured by the Moon. This is enough to produce a noticeable drop in the Sun’s brightness at mid-day.

Please exercise caution when viewing the Sun! Use appropriate eye protection or indirect observing techniques to project an image of the Sun. The link at the start of this paragraph leads to a great discussion on viewing the Sun safely. As always the single best source on the web (or anywhere) for eclipse and transit information is Fred Espenak’s eclipse website at NASA. Stop by whenever you have a question on upcoming events as well as viewing and photography tips.

Location Begins Maximum Ends Altitude Azimuth Magnitude
Honolulu 14:23 15:48 17:01 43 275 44
Hilo 14:31 15:56 17:05 61 270 47

Eta-Aquariid Meteor Shower

The early hours of dawn on May 5th will see the peak of the ηAquariid meteor shower. This is a reliable shower that produces anywhere from 30-80 meteors each hour near peak. Resulting from debris left behind by Comet 1P/Halley this shower approaches the Earth from the direction of the constellation Aquarius. As this constellation is quite low in the sky during the shower the meteors are entering the atmosphere at a low angle, this often results in meteors with long trains crossing much of the sky. A good shower that produces great fireballs.

Leonids in Orion
A pair of Leonid meteors streak through Orion
The ηAquariids seem to peak in activity every 12 years. As we are approaching the lull in this cycle it is likely that 2013 will produce a modest showing. That said, meteor prediction is an inexact science, no way of knowing ahead of time how good the shower will be.

IMO analyses in recent years, based on data collected between 1984–2001, have shown that ZHRs are generally above 30 between about May 3–10, and that the peak rates appear to be variable on a roughly 12-year timescale. Assuming this Jupiter-influenced cycle is borne-out, the next trough is due around 2014–2016, so ZHRs should be relatively modest in 2013, according to this idea – IMO website

The ηAquariid shower has a broad peak with several weeks of activity either side of the peak. The entire meteor shower lasts from around April 19 to May 28. Any morning from May 3rd to May 10th can be worth watching with rates to around 30 meteors per hour. The peak itself is predicted for 01:00UT on May 6th (15:00HST May 5th), but this shower often produces subpeaks as the Earth passes through clouds of debris left on successive orbits of Halley’s Comet.

The radiant for the ηAquariid shower does not rise until the last few hours of dark, about 2:30am, making this an early morning observing exercise. 2013 does offer decent viewing conditions, with only a slim waning Moon on the day of peak activity and new Moon occurring a few days later on the 10th. Remember, meteor watching can be enjoyed without any special equipment, just a dark sky and a safe place to watch from. Perhaps a good reason to get out under a dark sky? But then, should you ever need a reason to go observing, just go.

Appliance Repair

Eventually it will break.

This is the rule for household appliances. I would just prefer that it not be a two year old microwave that I had installed into the kitchen cabinetry. Yes, I can probably fix it… after I dismount it and lower it out of place. A task much easier typed than done. No matter, I am on-call this weekend. I will be around the house all day anyway, may as well get something productive done.

An over-the-stove microwave costs a few hundred dollars, too much to just run out and buy a new one. Not enough to justify a repair call. I do not even want to think of what it would cost to get a repairman out to the house. Driving from Kona? Hawaiian rates? I can think of few easier ways to get robbed.

Naked Microwave
Microwaves are pretty easy to work on, just get the cover off and everything is right there
I can fix this. Microwaves are relatively easy. Plus, it is an LG, you can actually buy the parts without going through an authorized extortionist. I have long ago learned not to buy certain brands, restricting appliance purchases to companies for whom you can actually find the manuals and buy the parts.

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Creationist Astronomy

Astronomy is a science where human timescales become insignificant. It seems like everything we are watching takes millions or even billions of years to occur. To be sure, there are a few things that happen quickly, like supernovae, but those events are the exceptions. Everywhere we look we see the stately dance of stars and galaxies, the formation of worlds. The dance is spread across distances and times so vast that even those who study the universe have difficulty comprehending the sheer immensity involved. Stars and planets take hundreds of thousands of years to form, a galaxy collision may go on for millions of years.

M6 The Butterfly Cluster
M6, the Butterfly Cluster
And yet there is a significant portion of our fellow citizens who insist that the universe is only a few thousand years old. I encounter this belief all too often, a dogged insistence that everything was created just a few thousand years ago. There are variations on the theme, with differing numbers, but these beliefs generally accept that our universe and the Earth were formed within the last ten thousand years. Never mind we have literally mountains of evidence to the contrary, when that evidence clashes with worldviews instilled since birth by a religion and parents, a discouraging number of people ignore reality and cling to what they were taught. To admit otherwise would open up too many other dearly held beliefs to questioning, a truly uncomfortable challenge.

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Saturn at Opposition

Today the planet Saturn will pass through opposition, directly opposite the Sun in our sky. The planet will be well placed for observation all night long, rising at sunset, transiting at midnight, and setting at sunrise.

During opposition the planet and rings will be slightly brighter than normal, an effect known as the opposition effect. The effect is most notable in the rings where the apparent brightness can increase by 30%. The effect is a combination of two factors, shadow hiding and the retro-reflective properties of the ring particles.