solar

Mercury Transit 2019

It was a clear predawn sky that greeted Waimea this morning, perfect to watch the transit of Mercury across the Sun.

The transit of Mercury on the morning of Nov 11, 2019

An alarm set for o-dark-thirty and a drive to Waimea with the first glow of dawn behind the mauna. I did not have to pack a ‘scope as I would be using an observatory outreach telescope, just make sure I have camera gear ready.

Realistically I was expecting only a few folks in addition to the club members I knew were coming. A light crowd maybe? Thus I was rather surprised to find the parking lot filling quickly and our big conference room buzzing at 6am.

It was quite the crowd considering the Sun had not yet appeared over the shoulder of the mauna!

A Reminder on Safe Solar Viewing

With the transit of Mercury on Monday a reminder on how to view the Sun safely is in order. I have posted on this subject many times in the past and maintain a full post on the various techniques one can use to safely view the Sun.

Scott in the Sun — Scott showing folks the Sun with a white light solar filter

Since Mercury is quite small you will want a bit of magnification to view the event properly. If you do not have a good solar filter for your telescope come to a local event where telescopes are available.

On Hawaiʻi island you can either go to the W. M. Keck Observatory HQ in Waimea or Subaru Observatory HQ in Hilo. Both observatories are hosting transit events at dawn Monday morning 11 Nov, 2019.

These events start at 6am with webcasts of the transit from other observatories further east, with the Sun rising far enough to see the transit from 7-8am.

Transit of Mercury Nov 11, 2019

On November 11th, 2019 Mercury will transit the Sun. While transits of Mercury are not rare, they are not all that common either. The last transit was a few years ago in May of 2016. On average there are fourteen transits of Mercury each century or one every seven years. If you wish to observe one the situation is much better than transits of Venus which occur in pairs over a century apart.

Mercury Transit 9May2016 — Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.

This particular transit will favor observers in Europe, South America, and the eastern seaboard of North America where the entire transit will be visible. Unfortunately for observers in the islands only the final hour and a half of the transit will be visible having begun well before local dawn. Sunrise will occur around 06:28 for the island of Hawaiʻi, with the transit ending at 08:04 in the morning when the Sun will be 20° above the horizon.

Xavier at the ‘Scope

A Better Solar Water Heater Electric Back-Up Timer

Another little problem around the house that can use a little creative circuitry to make it better. Do I really have to do it? No. I do it because I can, and because it is fun!

Solar Water Heater Back-Up Timer — A hot water heater timer setup for a solar water heater.

This time it is the electric back up heater for my solar hot water heater.

In Waikoloa solar hot water is an obvious addition to the house, we had it installed within a couple months of moving in. Considering electric power is about $0.40/kWh on the island, and tropical sunlight is quite intense, the use of solar to heat our water has been good money saving move… Long, hot showers with no guilt!

Once or twice a year we will get a period of heavy clouds and the water temperatures will fall to the point we need to turn on the electric back-up heating element in order to have that hot shower. Like most solar setups the storage tank has a electric element that will heat the water when needed.

Continue reading “A Better Solar Water Heater Electric Back-Up Timer”

Meadow Telescope

Solar Scope — A solar telescope setup to photograph the total solar eclipse 21Aug2017 in the meadow at Grant’s Spring, Oregon

Processing the Eclipse

Processing the frames to produce a deeper view of the solar corona is not easy. This is the best I have achieved so far. You can still see some ring like artifacts where the layers have been merged. I will be working further to improve this, but it may come down to retouching by hand to eliminate the issues.

The image is an HDR merge of five images taken from 1/500 to 1/4sec exposures with the TV-76 and a Canon EOS M5. Extensive corona and a couple prominences can be seen.

Tag: solar