Another weekend, another dive. This time at one of our favorite dive spots, Puakō End-of-Road. It was just Deb and I this time. The usual crew was out this weekend as well, but we had other goals in mind for the dive and choose to go to a closer site.
Brick Soldierfish (Myripristis amaena) in a cave at PuakōOne goal for the dive was testing some new kit. The new regulator performed pleasingly well, very easy breathing. Need to test it deeper, but for a first dive with new gear we kept it easy, around 40′ maximum depth. One issue is the mouthpiece, that simply has to change! I will be taking the mouthpiece off my old reg before the next dive. Need to rearrange the hoses as well, these
The other pleasant surprise was finding two new species of nudibranch. As Deb and I were diving without the rest of the crew, I was particularly slow. As usual poking my head into every nook and cranny. The result was finding examples of Phyllidiella rosans and Phyllidiopsis sphingis.
Going slow and shallow had another effect, almost 80 minutes underwater. Not a record for us, but high on the list of our longer dives. Not bad for a single aluminum 80 cylinder.
A nice Saturday dive, another hour spent underwater, and some new stuff found. A good day.
Known as M6, NGC6405, or The Butterfly Cluster, this pretty open cluster lies just above the tail of Scorpius. Visible to the unaided eye under a dark sky, it is an easy photographic target.
I have been working on improving the color balance in my astrophotos. Color is an interesting and complex subject in photography, worse in astrophotography. I think the results are much better here that in my previous work. Hope to take a few more photos this week and will continue to experiment.
M6, the Butterfly Cluster, 9 x 1min Canon 60D and AT6RC
A very thin Moon will rendezvous with Mercury this evening. The pair will separated by about 8° and at the same elevation, over 20° at sunset. The Moon will be a very thin crescent, only 7% illuminated. A little over 5° north of Mercury will be Pollux, with Castor a bit further north, both stars about a magnitude dimmer than the planet which is currently about zero magnitude.
A team of astronomers has used the Subaru Telescope and the W. M. Keck Observatory to discover the most distant galaxy yet, at 12.91 billion light-years from the Earth. This new galaxy, dubbed SXDF-NB1006-2, is slightly farther away than the previous record holder, galaxy GN-108036, which was found last year.
To identify SXDF-NB1006-2, the team used the Subaru Telescope to observe a total of 37 hours in seven nights in two wide fields of the sky. The team, led by Takatoshi Shibuya (The Graduate University for Advanced Studies, Japan), Dr. Nobunari Kashikawa (National Astronomical Observatory of Japan), Dr. Kazuaki Ota (Kyoto University), and Dr. Masanori Iye (National Astronomical Observatory of Japan), carefully processed the images they had obtained. Shibuya measured the color of 58,733 objects in the images and identified four galaxy candidates at a redshift of 7.3, which translates into about 12.9 billion light-years. A careful investigation of the brightness variation of the objects allowed the team to narrow down the number of candidates to two.
Color composite image of the Subaru XMM-Newton Deep Survey Field of galaxy SXDF-NB1006-2, credit NAOJ
Finally, the team needed to make spectroscopic observations to confirm the nature of these candidates. They observed the two galaxy candidates with two spectrographs, the Faint Object Camera and Spectrograph (FOCAS) on the Subaru Telescope and the Deep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck II Telescope, and identified one candidate for which a characteristic emission line of distant galaxies could be detected. The results are slated to be published in the June 20, 2012, edition of Astrophysical Journal.
In addition to locating the galaxy, the team’s research verified that the proportion of neutral hydrogen gas in the 750-million-year-old early Universe was higher than it is today. These findings help to decipher the early Universe during the “cosmic dawn,” when the light of ancient celestial objects and structures first appeared. They concluded that about 80 percent of the hydrogen gas in the ancient Universe, 12.91 billion years ago at a redshift of 7.2, was neutral.
Summer solstice occurs today at 13:09HST. Today the Sun will occupy the most northerly position in the sky of the year. The term solstice comes from the latin terms Sol (the Sun) and sistere (to stand still). On this day the Sun seems to stand still as it stops moving northwards each day and begins move to the south. This is the first day of summer as marked by many cultures in the northern hemisphere.
A very young moon over Waikoloa, this is only 26 hours after new, visible to the unaided eye as a sliver in the fading glow of sunsetNew Moon will occur today at 05:02HST.
We managed three dives last weekend. It was a holiday weekend, Kamehameha Day, that helped. But still, we average a couple dives a month, three dives in a weekend was a bit unusual. We dove with some friends at Pukao on Saturday. Then two more on the following Monday. This was conservative, a few of the guys dove on Sunday too!
Diver Mark Devenot cruising the reef at Hoover’s Towers north of HonokohauMonday’s diving was with Dennis. Again he invited us out on his boat. The Aqua Safari is quite comfortable, a 42′ cabin cruiser outfitted for diving. There are plenty of tank racks, a big swim deck and a very nice ladder. Dennis is quick to point out one of the best features… A warm fresh water shower on the swim deck! Which, I have to admit, is rather nice.
Thus, Monday morning saw us packing up the dive gear, a cooler with drinks and sandwich makings for everyone, and heading for Honokohau. There Deb and I joined Dennis and Mark for a very nice day diving.
We have been diving a lot in the NELHA area lately, I expect we will be diving some more there. It is some spectacular diving in the area. A rich reef sloping out to a steep drop-off that descends far beyond scuba depths. You look into the deep blue and know that somewhere down there is the abyssal plain, 8,000 feet below.
As usual I had my face in the coral, in and out of every crevice or small cave I came across. This is a great way to find the little stuff I love to photograph, but you can miss the big stuff… A series a sharp clangs gets my attention, the sound of Mark’s tank banger. I pull myself out of an alcove and swim over the large coral outcropping just in time to see a ten foot manta sweep by! The manta was just beyond the reef drop-off, against the deep blue of open water.
The find of the day was a Spanish Dancer, the largest nudibranch found in the islands. I do mean large, while most nudi’s I locate are an inch or two long, this fellow was the size of a dinner plate. Dancers have another feature… They Dance! Actually a form of swimming through undulating the body. I flushed him out of a crevice in the cave and the nudi proceeded to dance for us, everyone got a good look. After a few photos, actually quite a few photos, I carefully shepherded the pretty fellow back into the crevice I found him in.
No dives this weekend, I was on call. But we are already planning another outing next weekend. Summer diving season is here, bringing calm and clear water to the Kona side. The crew is ready to go, discussing where we will dive next.
As Venus approaches maximum elongation it will pass through the Hyades star cluster. Because Venus reaches it maximum western excursion on July 1st the planet will sweep out an arc that runs just inside the V-shape of the cluster. Thus the planet will remain within the main body of the cluster for the next 20 days.
Today the planet is only 26′ from εTau at one corner of the V-shaped cluster. On July 8th the planet will pass about 1° from Aldebaran as it exits the cluster at the other corner of the V.
