A Darker View

The planet Mercury is starting a morning apparition. The planet should become visible this week just above the dawn as a magnitude -1 object. The planet is moving more than 1° further from the Sun and higher in the morning sky each day, reaching a maximum elongation of 18° on October 15th.

Continue reading Mercury Appears in the Dawn…

A well made trail across the 1856 lava flow, allowing an easy crossing through the aʻa. Too well made, not something built by the State of Hawaii, this is older, much older. One feature of the old trails was large flat stones laid along the path. I suspect the trail was cut soon after the lava flow cooled, reconnecting the villages along this section of the Kohala coast.

Trail Across the Lava

An ancient trail across the lava flows at Kapalaoa

I had been hearing it was bad, I really did not know how bad.

Coral Bleaching

A cauliflower coral (Pocillopora meandrina) mostly bleached, just remnants of healthy coral with symbiotic zooxanthellae algae still in place

Last time we were diving south of Kona the reef looked really healthy. With all of the rains creating murky water we had not been out in over a month. While entertaining off-island guests we went to out favorite beach at Waialea Bay for a little snorkeling and swimming.

It is pretty bad.

The warm waters have been hard on our local corals. Nearly all of the cauliflower coral (Pocillopora meandrina) is completely white, completely bleached. The encrusting lobe and finger coral (Porites lobata) was better, but some colonies were looking a little lighter in color than I would like to see. Some of the other lobe corals (Porites evermanni) were also bleaching.

As we were snorkeling in a fairly shallow bay this could be a worst case sampling of the coastline. I hope so, it was distressing to see the reef under such stress. The water was warm, far warmer than I ever remember in my eight years on island.

The current El Nino event is forecast to last through the end of the year. It will be interesting to see if the corals recover, and how much of the colonies will die. I will have to make a point to swim the same section of reef a few more time as the fall turns to winter. I should swim to the same bit of reef and take a few more photos.

Mauna Kea Looms

Mauna Kea looms over the ranch lands of Waimea in the twilight

Today the planet Mercury passes through inferior conjunction, passing between the Sun and the Earth. In a week or so the planet will again be visible in the dawn sky, climbing higher each day. Maximum elongation will occur October 16th.

Continue reading Mercury at Inferior Conjunction…

“We swam in the Queen’s Bath this weekend”

“Oh? Which one?”

Queen's Bath

One of many freshwater pools along the Kohala Coast

Queen’s Bath is a name you will find scattered through vacation guides to the island of Hawaiʻi. The problem is that there is more than one, dozens actually. The name Queen’s Bath tends to be applied to any freshwater pool, particularly near the ocean. Some are small, some are quite large pools of crystal clear freshwater, a few are hidden in lava tubes.

There is the well known lava tube at Kihilo just a pebble’s throw from the surf. Enter through a skylight into the crisp, cool water. Bring a dive light and swim all the way to the back of the tube. Careful, there are boulders waiting to scrape the shins of an unwary swimmer, reef shoes or river sandals are the ideal footwear here.

Another Queen’s bath is found on the grounds of the Kaloko-Honokōhau National Historic Park. The park requests that you refrain from swimming in this one.

There are any number of pools along the Kohala Coast, particularly the low-lying section from Puako to Kiholo bay where enormous amounts of fresh water find their way into the sea. These often have reef fish trapped within, perhaps washed in by the winter surf. Other species of fish prefer these pools, grazing on the algae growing in the shallow, warm water.

Queen's Bath

The lava tube Queen’s Bath at Kiholo

The Puna coastline hosts many pools along the shoreline. Kaimū beach at Kalapana hosted one of the most famous Queen’s Baths. It was lost to the lava on the 1990’s as successive flows covered the area and destroyed the famous black sand beach. I have heard the pool at Ahalanui Park called a Queen’s bath, yet another example of the confusion.

Some of these pools are brackish, the salt water mixing with fresh. The result is a swirling view through a dive mask with the mixed refractive indexes, looking a bit like mixing water and oil. As one swims away from the ocean the water becomes fresher, you often find startlingly cool currents where the fresh water enters the pool. Often the tides will affect the depth of the water in the pool, even pools a hundred yards from the ocean rising and falling as the tide backs up the flow of water.

Many of the pools are local secrets, directions not available to outsiders. Places where a hot afternoon can be enjoyed, swimming in the cool waters. I know a few of these, don’t ask me where to find them.

I had planned to go up and photograph the tail end of tonight’s eclipse as the full Moon rose just inside the mountain shadow… No luck.

Thanks to tropical storm Niala passing south of the island the summit is totally weathered in. Fog, rain and no shadows…

Summit Fog and Rain

Current view from MastCam of a foggy, rainy summit. No eclipse to be seen tonight.

They got lucky.

Cliff Livermore

Cliff setup and ready for viewers at WHEA.

I often caution folks scheduling star parties in Kona that the afternoon and evening clouds will often spoil the attempt. The large Hualalai volcano is the culprit here. In the afternoon the clouds form in the lee of the mountain and give Kona the afternoon showers that nourish the rich rainforest found on the upper slopes.

We try anyway.

WHEA, or West Hawaii Explorations Academy is a charter school located in the NELHA complex just north of Kona and just south of the airport. They concentrate on science, mostly marine science, with an outdoor hands-on curricula. Large pavilions serve as additional classrooms. The campus is littered with evidence of various projects, from large pools, various gardens, and a phalanx of handmade cargo pallet catapults in the back.

Maureen Salmi

Maureen using her big dob at WHEA.

The school was having an overnight camp-out on campus, providing a large crowd of students wanting a look through a telescope.

There were some clouds to hamper us, but nothing that would obscure the view for more than a minute or two. A nearly full moon, just a few days shy of this week’s eclipse, was beautiful in the telescope. We also had Saturn, still available in the evening sky at the head of Scorpio. As the evening passed so did the clouds, thinning to a few wisps across the sky.

Maureen was there with her big dob. Chris and Doris with the C-14, Brad with his twin refractor that shows the Moon beautifully. Cliff set up the C-11 giving us five telescopes in all, plenty of eyepieces to supply visions to waiting eyes. I need to spend a little time working on our NextStar GPS 11″, the motor control issue is back, I was running in manual mode much of the evening.

We gazed at the terrain of the Moon and I showed kids, and a few teachers, how to take photos with a cell phone through the eyepiece. A good school star party and a well spent Friday evening. Even if it did take half an hour for the security guard to arrive to open the gate and let us leave. There were also too many chocolate chip cookies available.

Full Moon

Full Moon taken 27Aug2007, 90mm f/12 APO and Canon 20Da

Full Moon will occur today at 16:50HST.

This full moon is a perigee full Moon, with the moment of lunar perigee occurring at 15:46, about an hour away from full moon. This full Moon will be a bit larger and a bit brighter than an average full moon.

Along with perigee, a total lunar eclipse will occur with this full Moon. Observers on either side of the Atlantic, including western Europe and the eastern seaboard of North America will be able to see the entire eclipse. Observers in Hawaii will only be able to see the last moments of the penumbral eclipse, not significant and not visually observable.

Continue reading Full Moon…

The NASA New Horizons team has released a gorgeous full disk image of Pluto. I would predict that this high resolution image will be the definitive image of Pluto for at least a century. Expect to see this image any time you run across Pluto in any media, from Wikipedia to school textbooks.

Panning across the image one can see that Pluto does feature a fair number of impact craters, more than I noted on the earlier images that often concentrated on the ice fields of the Sputnik Planum. This ice cap is startlingly smooth, with flow features visible, primarily at the margins. The ice is probably nitrogen ice as water is essentially a rock at these temperatures. Indeed much of the bedrock visible across the image is probably water ice.

The ice sheet is made up of polygons, a feature sometimes seen in ice here on Earth. For some reason the boundaries of the polygons are marked with long linear double depressions. These depressions look like 4WD roads across a desert of sand, if the vehicles had tires a mile across.

On the right side of the ice fields of Sputnik Planum there are a a large number of aeolian features, huge ridges one would suppose are aligned with the prevailing winds. Given that the image resolution is 0.8 miles per pixel these features must be miles high. These have recently been dubbed snakeskin terrain. I expect the planetary scientists will have a bit of fun trying to figure these out.

It is a beautiful image, conveying a great sense of what this dwarf planet is really like. Download the high resolution image and just wander. The larger image is bigger than WordPress will allow, use the link above to get the full size image.

NASA’s New Horizons spacecraft captured this high-resolution enhanced color view of Pluto on July 14, 2015.

NASA’s New Horizons spacecraft captured this high-resolution enhanced color view of Pluto on July 14, 2015. Credit: NASA/JHUAPL/SwRI