A Second Chance for Lāhainā Noon

Lāhainā Noon is that moment when the Sun is directly overhead. At the moment of Lāhainā Noon shadows disappear.

The first Lāhainā Noon of the year occurs in May as the Sun is moving northwards in the sky. The second chance to see Lāhainā Noon is in July as the Sun moves back to the south.

The table below gives the dates and times for this second Lāhainā Noon across the islands.

Lahiana Noon for July 2019
CityLong.Lat.DateTimeElevation
Naalehu 155°35’W19°03’NJul 2712:29HST89.9
Hilo 155°05’W19°42’NJul 2412:27HST89.9
Kona 155°59’W19°39’NJul 2512:30HST89.9
Waimea 155°40’W20°01’NJul 2312:29HST89.9
Hawi 155°50’W20°14’NJul 2212:30HST89.9
Hana 156°00’W20°46’NJul 1912:30HST89.9
Kihei 156°27’W20°45’NJul 1912:32HST90.0
Kahalui 156°28’W20°53’NJul 1812:32HST89.9
Lahaina 156°40’W20°53’NJul 1812:33HST89.9
Lanai City156°55’W20°50’NJul 1812:34HST89.9
Kaunakakai157°01’W21°05’NJul 1712:34HST89.9
Honolulu 157°49’W21°18’NJul 1612:37HST89.9
Kaneohe 157°48’W21°25’NJul 1512:37HST89.9
Waialua 158°08’W21°34’NJul 1412:38HST89.9
Lihue 159°22’W21°58’NJul 1112:43HST89.9
Data from US Naval Observatory Data Services

Waimea Lāhainā Noon Reminder

Today at 12:19HST will be Lāhainā Noon in Waimea on the Big Island, the moment when shadows disappear.

The exact date and time varies significantly across the islands and from year to year. The table below shows the time of Lāhainā Noon for various cities in 2019.

Lahiana Noon for May 2019
CityLong.Lat.DateTimeElevation
Naalehu 155°35’W19°03’NMay1512:19HST89.9
Hilo 155°05’W19°42’NMay1812:17HST89.9
Kona 155°59’W19°39’NMay1812:20HST89.9
Waimea 155°40’W20°01’NMay2012:19HST89.9
Hawi 155°50’W20°14’NMay2112:20HST90.0
Hana 156°00’W20°46’NMay2312:21HST89.9
Kihei 156°27’W20°45’NMay2312:23HST89.9
Kahalui 156°28’W20°53’NMay2412:23HST89.9
Lahaina 156°40’W20°53’NMay2412:23HST89.9
Lanai City156°55’W20°50’NMay2412:24HST89.9
Kaunakakai157°01’W21°05’NMay2512:25HST89.9
Honolulu 157°49’W21°18’NMay2612:28HST89.9
Kaneohe 157°48’W21°25’NMay2712:28HST89.9
Waialua 158°08’W21°34’NMay2812:30HST89.9
Lihue 159°22’W21°58’NMay3112:35HST90.0
Data from US Naval Observatory Data Services

Hilo & Kona Lāhainā Noon Reminder

Today will be Lāhainā Noon in Hilo and Kailua-Kona, the moment when shadows disappear.

The event will occur at 12:17HST in Hilo, and three minutes later further west in Kailua-Kona at 12:20HST.

The exact date and time varies significantly across the islands and from year to year. The table below shows the time of Lāhainā Noon for various cities in 2019.

Lahiana Noon for May 2019
CityLong.Lat.DateTimeElevation
Naalehu 155°35’W19°03’NMay1512:19HST89.9
Hilo 155°05’W19°42’NMay1812:17HST89.9
Kona 155°59’W19°39’NMay1812:20HST89.9
Waimea 155°40’W20°01’NMay2012:19HST89.9
Hawi 155°50’W20°14’NMay2112:20HST90.0
Hana 156°00’W20°46’NMay2312:21HST89.9
Kihei 156°27’W20°45’NMay2312:23HST89.9
Kahalui 156°28’W20°53’NMay2412:23HST89.9
Lahaina 156°40’W20°53’NMay2412:23HST89.9
Lanai City156°55’W20°50’NMay2412:24HST89.9
Kaunakakai157°01’W21°05’NMay2512:25HST89.9
Honolulu 157°49’W21°18’NMay2612:28HST89.9
Kaneohe 157°48’W21°25’NMay2712:28HST89.9
Waialua 158°08’W21°34’NMay2812:30HST89.9
Lihue 159°22’W21°58’NMay3112:35HST90.0
Data from US Naval Observatory Data Services

Lāhainā Noon

Lāhainā Noon is that moment when the Sun is directly overhead. At the moment of Lāhainā Noon shadows disappear.

As the islands lie south of the Tropic of Cancer there is a day when the Sun will pass directly overhead as the summer solstice approaches, generally in late May. There is a second noon as the Sun’s position moves south again in July.

The term Lāhainā Noon is unique to the islands, being adopted by the Bishop Museum in the 1990’s to describe this event. The Hawaiian term lā hainā translates roughly as cruel Sun.

The exact date and time varies significantly across the islands and from year to year. The table below shows the time of Lāhainā Noon for various cities in 2019.

Lahiana Noon for May 2019
CityLong.Lat.DateTimeElevation
Naalehu 155°35’W19°03’NMay1512:19HST89.9
Hilo 155°05’W19°42’NMay1812:17HST89.9
Kona 155°59’W19°39’NMay1812:20HST89.9
Waimea 155°40’W20°01’NMay2012:19HST89.9
Hawi 155°50’W20°14’NMay2112:20HST90.0
Hana 156°00’W20°46’NMay2312:21HST89.9
Kihei 156°27’W20°45’NMay2312:23HST89.9
Kahalui 156°28’W20°53’NMay2412:23HST89.9
Lahaina 156°40’W20°53’NMay2412:23HST89.9
Lanai City156°55’W20°50’NMay2412:24HST89.9
Kaunakakai157°01’W21°05’NMay2512:25HST89.9
Honolulu 157°49’W21°18’NMay2612:28HST89.9
Kaneohe 157°48’W21°25’NMay2712:28HST89.9
Waialua 158°08’W21°34’NMay2812:30HST89.9
Lihue 159°22’W21°58’NMay3112:35HST90.0
Data from US Naval Observatory Data Services

A Tale of Two Earthquakes

Two earthquakes of the same magnitude strike our island a month apart. Two events that are quite interesting to us at the observatory. Both about the same magnitude, both occurring deep in the island, one was far more forceful at the telescopes causing some minor damage, the second caused no damage that we have found despite a thorough inspection.

Mauna Kea seen at dawn from Mauna Loa
Mauna Kea seen at dawn from Mauna Loa

Any strong earthquake is a concern for the telescopes. We need to know immediately just how strong the quake was, how much potential for damage occurred.

The telescopes are precision instruments with many delicate parts. On the other hand earthquakes are common on this volcanic island and we have learned how to deal with the shaking.

When attempting to measure the possible damage to the telescope it is not earthquake magnitude that is interesting. Rather we want to know the peak ground accelerations that occur at the summit facility. The actual forces that could potentially cause damage. These are measured by means of a logging accelerometer mounted in the basement of the observatory.

Continue reading “A Tale of Two Earthquakes”

Where can you fly a drone in Hawaii?

For a new drone pilot, learning the rules can be a bit daunting.

Hawaiʻi is a state that is incredibly attractive to a drone pilot. The scenery, from reefs and beaches, to the soaring volcanoes, just begs to be flown over and photographed from the air.

Flying the DJI Mavic Air in the saddle at the base of Mauna Kea
Flying the DJI Mavic Air in the saddle at the base of Mauna Kea

I am determined to fly responsibly, that means going through all of the various rules. The rules are not simple! They are a patchwork of regulations from federal, state, and local authorities. How do you make sense of it all?

Below is the results of my research on the subject. More than a few hours of reading state and federal websites. The process of writing this post was in itself a means of educating myself. Hopefully others will find this useful. If you know of anything I have missed, drop me a line to let me know.

This post is focused on the Island of Hawaii, home for me. But much of what is discussed here applies to all of the islands.

Continue reading “Where can you fly a drone in Hawaii?”

Mauna Kea Adze Quarry

The AO system was broken, nothing really bad, but something I would need to go up and fix. Reading the nightlogs each morning there are occasionally surprises like this, a sudden re-planning of an otherwise lazy Sunday.

Workshop
A workshop in the Mauna Kea adze quarry

I suspected that the fix would not take me long at all. But I would be on the mountain… What to do with the rest of the day? I load camera and hiking gear along with my backpack of tools. If I do complete the job quickly I will go hiking. The Mauna Kea adze quarry springs to mind as a likely spot to spend a few hours.

The ancient Hawaiians had no access to metal on these volcanic islands. What they did have was a source of very hard volcanic rock. High on Mauna Kea there were once glaciers, a place where the fury and heat of the volcano met ice. Cooling quickly in the icy realm the lava formed a dense, fine grained rock suitable for making tools.

The rock from this quarry could be shaped and ground into a number of tools, particularly adzes that could be used to cut wood or carve the great ocean going canoes. Tools made from this particular rock were so prized that they have been found in archaeological sites on distant islands across the Pacific.

I have known how extensive the adze quarry is for years. The numbers are abstract, number of find sites mapped, square kilometers of area, just numbers on paper. What I found was quite different than what I was expecting, nothing conveys the actuality of being there.

I was amazed at the sheer size of the piles of flakes. These are sites that were worked for centuries, each workshop accumulating many tons of waste rock flake to tumble down the slope. Having worked with my hands continually over my lifetime, I know how hard hand labor like this is. I stood amazed at the sheer amount of human effort it took to accumulate these piles.

I found I had another misconception to correct… Looking from a distance you see the caves with piles of waste rock spilling down. I had assumed that the caves and ledges are where the actual mining took place, where the basalt was pried from the mountain. Visiting one of the workshops I quickly see this is not the case.

Continue reading “Mauna Kea Adze Quarry”

Fungus on Glass

The tropical environment of Hawaiʻi is not kind to optical instruments. Tropical humidity can cause a host of issues ranging from corrosion of metal parts to decay of wooden and cardboard telescope structures. For those of us who build and use small telescopes the issues of tropical heat and humidity are rather concerning.

Fungus on Glass
Fungus colony on a small achromatic lens surface
Worst of all is the fungus. Impressively there are species of fungus that can grow and thrive on clean optical surfaces. It is hard to imaging a more hostile place to grow, seemingly devoid of nutrients and the moisture necessary for life.

I have seen camera lenses lost to the white fungus. A friend once showed me a Canon 70-200 f/2.8 L, a $2000 lens, with fungus covering internal elements. Even on the “dry side” of Waimea the humidity was high enough to allow fungus to destroy this lens.

The problem is not an issue on the summit of Mauna Kea. The high altitude air typically exhibits a relative humidity of less than 10%. Several references note that a humidity of above 70% is needed to promote fungal growth on optics. We see no issues with fungal damage to the mirrors or instruments on the big ‘scopes.

Below the tropical inversion layer (about 6-7k feet) it is another issue entirely. Near sea level, where most of us live, humidity can remain above 80% much of the year. The warm and humid conditions of these islands are idea for growing anything, including the omnipresent fungal gardens that create the smells of a tropical landscape. Fungus is inescapable in this world, the spores drift on the wind and an stay dormant for decades, anywhere conditions are suitable fungus will grow.

The possibility of equipment damage was a major element in our buying a house. Waikoloa is located within one of the driest areas of the island. The humidity typically hovers in the 50’s, dry enough that I have had no issues with the multiple telescopes stored in the garage. Still, I do inspect stored equipment periodically, looking for the dreaded white fungus or other damage wrought by this tropical climate.

It is not a single species of fungus responsible for the problem. Apparently quite a few species are able to colonize an optical surface. Looking through the literature I find referenced to multiple species that can grow on optical glass…

The fungi which grow in optical instruments belong to the groups Phycomycetes, Ascomycetes and Fungi Imperfecti. The following species were frequently isolated from instruments which had been in New Guinea: Penicillium spinulosum, Thom.; P. commune, Thom.; P. citrinum, Thom.; Aspergillus niger, Van Tiegh.; Trichoderma viride, Pers. ex-Fr.; Mucor racemosus, Fres.; and M. ramannianus, A. Moeller. So far, Monilia crassa has not been isolated from Australian instruments, although Dr. W. G. Hutchinson (5) of the United States, found this to be a common species in the Panama zone, and it has also been recorded as frequent in West Africa by Major I. G. Campbell. – J.S. Turner, et al.1

I admit that the fungus can be pretty, in an odd sort of way considering the damage. Under a microscope it appears lacy, the mycelium fibrils growing across the glass in search of more nutrients to support the colony. In the center small round fruiting bodies are the launching point for new fungal spores.

I recently had another round of battle with fungus while restoring a collection of instruments that had been stored in a garage on the side of Hualalai. The high humidity had wrought impressive damage on both the optics and metal components of the telescopes. And there is fungus! Found in the eyepieces and on the telescope mirrors. During the cleaning and restoration of the instruments I found it necessary to completely dismantle many optical assemblies just to remove and kill the fungus. I some cases I was in time, but not completely, it is not without regret that I throw a $400 eyepiece into the trash.

Dealing with the fungus is imperative, cleaning and killing the growth before severe damage can be done may save the equipment. If the growth is severe enough the glass surface and the coatings can be damaged. Apparently the fungi can excrete hydrochloric acid, etching the surface and creating permanent damage.

Fungus on Glass
Fungus colony on a small achromatic lens surface
Minor damage may not be enough to ruin the device. It actually takes a great deal of damage to appreciably affect the performance of most optics. A few small specks of damage remaining on the surface after cleaning may not be noticeable. Inspection of each spot of damage with a microscope can be useful, Sometimes it is clearly damage of the surface and irrepairable. I have also found hard deposits that at first glance appeared to be damage under the core of fungal colonies that remained after cleaning. These may be removed using a soft wooden tool like a toothpick or chopstick.

Killing the fungi requires a solvent that will both kill the fungus while not damaging the optical surface. I find references to both alcohol as well as other solvents. A mix of 50/50 hydrogen peroxide and ammonia is recommended by some references. Along with cleaning the glass I am careful to soak all of the structural elements as well. The tube, the spacers and lock-rings can all harbor minuscule colonies or spores awaiting suitable conditions to grow again.

Optical fungicide solutions tend to be expensive and hard to obtain, but they are available from some optical equipment manufacturers. Alternatively, you can use a 50/50 mix of hydrogen peroxide (H2O2) and ammonia (NH3). Usually, 5 ml of each is adequate (10 cc in total). Mix just prior to use and do not store the mixed product. – Ismael Cordero, Community Eye Health Journal2

Living in a warm humid environment one must be vigilant and ready to deal with issues when found. Examine optics regularly, keep a can of WD-40 next to the tool box (and use it), store optics and electronics with plenty of ventilation and reduce the humidity to well below 70% if needed. Extra vigilance to preserve valuable equipment is the price of living in paradise.

  1. Tropic-Proofing of Optical Instruments by a Fungicide, J.S. Turner, E.I. McLennan, J.S. Rogers, & E. Matthaei, University of Melbourne, Nature 158 (Oct. 5, 1946) 469-473.
  2. Fungus: how to prevent growth and remove it from optical instruments, Ismael Cordero, Comm Eye Health Vol. 26 No. 83 2013 pp 57

An 1835 Map of Hawai’i

Among the items I found in the NYPL image collection was an 1835 map of the Hawaiian Islands. I included it in the posting on the collection, but the map truly deserves a closer look. It preserves the western view of the islands as of the early 19th century.

The map is reasonably accurate, looking at the coordinates given for key points in the islands shows that they are correctly plotted. The outlines of the islands are mostly familiar. The shapes of Molokai, Maui, and parts of Hawaiʻi do show some odd features that look odd to anyone with a good knowledge of local geography. Any number of points and bays seem exaggerated, note the peninsulas on the north shores of Oahu and Maui. Notably Kealakekua bay is drawn as much more sheltered than it really is, an odd inaccuracy in a maritime map.

Continuing inspection reveals a number of other oddities… There are two islands marked on the map south of Niʻihau, named Tahoora and Papappa. Modern navigation maps mark only one island here, Kaʻula. Tahoora (Kaʻula) was spotted by the Cook expedition and recorded with that name. Reference to Papappa can be found in the 1870 Seaman’s Guide to the Islands of the North Pacific, Part II, W. H. Rosser. Apparently local fisherman reported another island south of Kaʻula. A number of ships looked for such an island in vain. The guide lists its existence as “doubtful”.

Map of the Hawaiian Islands 1835
Map of the Sandwich Islands (Hawai’i) issued in 1835 by Jacobus Boelen

It is also interesting to note that the coordinate system used is referenced to Greenwich. Thus the longitudes marked at the bottom match those found on modern maps. At the time the prime meridian, the location of zero longitude, was hotly contested between several possible locations. It was not until the 1884 International Meridian Conference that Greenwich became the accepted standard worldwide. This was over the objections of the French who abstained from the vote and continued to use the Paris meridian until 1911.

Of course it is the place names that are the most fascinating feature of the map. Setting aside the Dutch vocabulary and looking just at the transcriptions of the Hawaiian place names one sees familiar names as they were used two centuries ago.

Looking about the map one will note Owhyhee in place of the modern Hawaiʻi, Mowee and Woahoo as the old versions of Maui and Oaho, quite recognizable. If you have read the old accounts you may recognize Atooi as the island of Kauai. We also see Mowna Kaah printed on the map for present day Mauna Kea, similar to the Mauna Kaah found in the Cook expedition journals as the first written version of the mountain’s name.

Map Name Current Name
Atooi Kauai
Honoruru Honolulu
Karakakooa Kealakekua
Mowna Kaah Mauna Kea
Mowna Worroray Hualālai
Mowna Roa Mauna Loa
Morokinne Molokini
Morotoi Molokai
Mowee Maui
Oneeheow Niʻihau
Oreehoua Lehua
Owyhee Hawai’i
Ranai Lanai
Tahoora Kaʻula
Tahoorowa Kahoʻolawe
Woahoo Oahu

Currently accepted place names compared to the names found on the 1835 map by Jacobus Boelen

Pineapple

Another experiment in growing tropical fruit… Deb had sprouted a pineapple using the top to one she had bought at the farmers market. With roots showing she asked me to set up a more appropriate home for the plant. That came in the form of a large pot on our front lanai. I was surprised when the pineapple not only survived but thrived. the plant is an attractive pot plant just outside our front door. I have shared some photos of the geckos and anoles that call the plant home.

Then the first signs of blooming appeared… In place of a new leaf a little spiky ball appeared at the center of the plant. This has developed into a very nice looking fruit, a recognizable pineapple covered with little purple blossoms. It is another tropical fruit I never imagined myself growing, one of the interesting things about living in Hawaii.

Now I just need to figure out when to harvest it!

Pineapple
A pineapple in fruit on our front lanai