Clear Skies
Author: Andrew
An electrical engineer, amateur astronomer, and diver, living and working on the island of Hawaiʻi.
Full Moon
Full Moon will occur today at 03:34HST.
This evening look for the Moon rising in the east just as the Sun sets in the west. Across the Big Island this can often lead to moonbows as the low elevation moonlight interacts with fog and clouds.
Continue reading “Full Moon”Transit Viewing
Mercury Transit 2019
It was a clear predawn sky that greeted Waimea this morning, perfect to watch the transit of Mercury across the Sun.
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!
Continue reading “Mercury Transit 2019”Mercury at Inferior Conjunction
Today Mercury is passing through inferior conjunction, passing between the Sun and the Earth. This fast moving planet will reappear above the dawn in about a week, rising towards maximum elongation on November 28th.
On this particular conjunction the planet will transit the Sun.
This will be a modest apparition, with the planet reaching only 20° away from the Sun.
| Mercury Events for 2019 | |||
|---|---|---|---|
| Apparition | Date | Elongation | Magnitude |
| Evening | Feb 27 | 18.1°E | -0.2 |
| Morning | Apr 11 | 27.7°W | +0.6 |
| Evening | Jun 23 | 25.2°E | +0.7 |
| Morning | Aug 9 | 19.0°W | +0.3 |
| Evening | Oct 20 | 24.6°E | +0.1 |
| Morning | Nov 28 | 20.1°W | -0.3 |
| Data from the Mercury Chaser’s Calculator by John Walker | |||
Observing a Transit
Transit of Mercury Reminder
Tomorrow morning, November 11th, there is a transit of Mercury. For observers here in the islands the event will be in progress when the sun rises, only the last hour and a half of the even visible.
You can read a full post with all of the event details here.
This is the last transit of Mercury until 2032, you might want to get out to see this one.
Leonid Meteor Shower
The Leonids are one of the better known annual meteor showers. Some years see high Leonid activity, with amazing numbers of meteors. This shower has occasionally created true meteor storms. Unfortunately 2019 is not predicted to be one of those years, with very modest numbers expected.
Due to the gravitational influence of Jupiter, the Leonids are not expected to produce any exceptional showers for some decades. We are unlikely to see any repeats of the early 21st century storms anytime soon.
The shower will peak on November 17, with an expected ZHR of around 15 meteors per hour. The Leonids exhibit a broad peak allowing viewing for days before and after maximum. Moonlight is a bit of an issue with a waning gibbous Moon 5 days after full on the 17th.
A Wake-Up Quake
This one woke up everyone in the house, cats included.
While the eruption of 2018 had the island shaking, 2019 has had seemingly few felt earthquakes. I have gone several months without feeling a quake.
It was something of a surprise when the house rattled this morning just before 6am.
Deb asked me, “Was that a quake?”
“Yes.”
From the short, sharp rattle I guessed it was close… I was right, a magnitude 3.1 in North Kohala. It was also deep, a bit over 14 miles down. This was a classic settling quake as the weight of the island presses into the ocean crust.
On a Saturday morning we did not stay awake for long, cats included.
Update: The quake was later upgraded to a 3.4 after review by the USGS.
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.
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.