Venus is quickly rising in the dawn, appearing higher each morning. Today the planet will rise at 06:08HST, about 50 minutes before the Sun and be almost 12° above the horizon at sunrise. The planet will be quite prominent in the dawn sky for the next few months, reaching maximum elongation on March 22nd at 46.6° west.
When the planet rises far enough to catch in a telescope you will see a thin crescent that waxes a little each day.
Look for a nice pairing of this brilliant planet and a thin crescent Moon on the morning of January 28th.
Gliding across the sand, a handsome sea star catches my eye. These stars spend the day under the sand, hiding from the many predators that hunt with the light. In the darkness it rises and begins its own hunt. While two arms seem to be in the process of regrowing, the star is otherwise quite healthy. I wander off into the dark, wondering what prey the starfish is seeking, what will be eaten tonight.
A starfish (Luidia aspera) hunting across the sand at night, 40′ depth, Mahukona
Today an amateur astronomy icon passed away. John Dobson popularized the very simple design of telescope that came to bear his name, the Dobsonian. As a Vedantan monk John possessed few material means, pursuing a passion for telescope building in the monastery garden shed he designed a telescope that could be built from whatever scrap parts he could scavenge. He could often be found around San Fransisco showing the wonders of the night sky to anyone who would look through one of his telescopes. His infectious enthusiasm for astronomy led him to help co-found the San Francisco Sidewalk Astronomers.
Chris Fuld using his monster 40″ dobsonian at Oregon Star Party 2013
The Dobsonian is a telescope that is characterized by an extraordinary simple and robust design. Made of plywood and other hardware store parts, there was nothing in the design that could not be built by hand.
The optical layout is a standard Newtonian design with the eyepiece at the front of the telescope. This allows the heavy primary mirror to be located quite close to the ground. The entire telescope rotates on a simple lazy-suzan azimuth bearing made of plywood, formica and teflon blocks. A simple set of trunnions allows the telescope to be raised and lowered in elevation.
Steve Dillinger’s 20″ Dob awaiting full dark at Sentinel, AZ with Venus and the Moon shining behind
The Dob brought large aperture astronomy into reach of thousands of backyard observers. Anyone with a modicum of skill could build a Dob in a garage with simple hand tools. Commercial designs soon appeared at very affordable prices.
Amateur telescope makers have built upon John’s ideas, creating elegant designs that far surpass those simple telescopes made from scrap. Aircraft grade plywood, machined aluminum frames, carbon fiber and computerized controls are common in modern Dobsonians. The design can be scaled up, Dobsonians are sometimes enormous, with telescopes of 30 or 40 inches aperture seen at many star parties. At OSP last year I setup next to a 40″ built by Chris Fuld, a monster telescope built by hand.
John spent much of his later life touring wherever dark skies, telescopes and people could be found. This often included national parks and regional star parties. I met John a few times across the years, at Grand Canyon Star Party and at an evening observing session at Starizona, an astronomy shop in Tucson. His signature graces the secondary cage of my 18″ f/4.5 Dobsonian, Deep Violet, beside the signature of David Levy.
John Dobson’s signature on the secondary cage of Deep Violet
John was also a proponent of a decidedly non-standard cosmology, believing that the Big-Bang model had fatal flaws. His alternate ideas make… Uh? Interesting reading. He describes a recycling steady state cosmos heavily influenced by the teachings of eastern religions and mystical thought.
John Dobson died today, 15 January 2014 at the age of 98 in Burbank, California. John leaves behind a son, many friends, and a community indebted by his contributions to amateur astronomy. My friend Dean Ketelsen knew John far better than I did, I suggest you read his notes on his passing.
I spent a few moments and put all of the photos of dobsonian telescopes that have appeared here on Darker View into a gallery. The photos are just a little sliver of what John Dobson meant to amateur astronomy…
Almost all of the big dobsonian telescopes to be found on Hawai’i show up at the VIS for the night.
David Nemo and his handmade 20″ string telescope
Chris Fuld collimating his 40.5 inch dobsonian
The 18″ setup at 9000ft on the side of Mauna Kea
Steve Dillinger’s 20″ Dob awaiting full dark at Sentinel, AZ with Venus and the Moon shining behind
A 12.5″ dobsonian telescope after the refit
Olivier beside his new telescope, a 12″ Orion Dobsonian
Cliff at the eyepiece of his 24″
Looking into the mirror box with the mirror mount in place
Gluing the mirror box with a cage ring atop to check the fit
Looking down the observing line at Oregon Star Party 2013
Looking at the mounted mirror cell and primary mirror
Mark Folkerts preparing his equipment for the night
Deep Violet at the Mauna Kea Visitor Information Station
Assembling the truss tubes and secondary cage
The rocker box between coats of polyurethane
Deep Violet set up neat the Dragoon Mountains in Southern Arizona
Bob Clements demonstrates his 10″ dobsonian with an equatorial platform
Secondary Cage with the focuser, digital setting circles and Telrad
Chris Tribe with his 20″ f/4.5 built from ultralight materialsChris Tribe with his 20 inch f/4.5 built from ultralight materials
Ken and Ann Jones oberving with their 18″ at Oregon Star Party 2013
The ground board with center pivot and teflon pads in place
Deep Violet fully assembled and nearly ready for dark
Gluing the laminate to the rocker box to create the azimuth bearing
Under Arizona stars at Las Cienegas
Ken Jones observes with his 18″ dobsonian
The author’s setup awaiting a dark December sky with Deep Violet
Detail of an elevation bearing and encoder
Preparing to set up the telescope
Deep Violet packed in the rear of my Ford Explorer
Tony shows a group of enthusiastic student views with his 12.5″ dob.
The Sky Commander digital setting circles mounted to the secondary cage
Looking into the mirror box without the primary and mount in place
Gluing the gussets into the mirror box
The author waiting for dark at the 2005 All Arizona Messier Marathon with my usual visual setup including Deep Violet
Telescopes at Oregon Star Party 2013
Sunset at Arizona City awaiting dark
Chris Fuld using his monster 40″ dobsonian at Oregon Star Party 2013
First light atop Kitt Peak
Routing the top of the rocker box to create the elevation bearing
Setup among the saguaros of the Tortillita Mountians
The 18 point mirror cell, built to the plans from Barry & Kriege
The Board of Directors of the W. M. Keck Observatory announced today that Taft Armandroff, executive director of the world’s premier ground-based astronomical observatory, will step down on June 1 to become a professor at the University of Texas at Austin, and director of its McDonald Observatory.
W. M. Keck Observatory Director Taft Armandroff Credit: Ethan TweedieArmandroff joined Keck Observatory in June 2006. During his tenure, the observatory continued to be a global leader in optical and infra-red astronomy. Keck Observatory serves nearly five hundred astronomers drawn not only from the United States but also from around the world, including Australia. The observatory also provides ground-based support for the National Aeronautics and Space Administration (NASA).
Before coming to Keck Observatory, Armandroff worked at the National Optical Astronomy Observatory (NOAO) in Tucson, Arizona, for 19 years, holding positions of associate director and director of the NOAO Gemini Science Center. He is a 1982 graduate in astronomy of Wesleyan University, and he earned his Master’s and Ph.D. degrees in astronomy from Yale University. His scientific research has focused dwarf spheroidal galaxies, stellar populations in the Milky Way galaxy and nearby galaxies, globular clusters, chemical evolution of galaxies, and dark matter.
As executive director of the W. M. Keck Observatory, Armandroff reports to a governing board representing the observatory’s founding partners, the California Institute of Technology (Caltech) and the University of California (UC). The governing board also has liaisons from the NASA, the W. M. Keck Foundation, and the University of Hawaii. In 2013, Keck Observatory managed a budget of $25 million to support the organization’s 120 professional staff, operations, and advanced instrument initiatives.
“Taft did an exceptional job in maintaining the high productivity of Keck Observatory,” said Tom Soifer, Caltech Professor of Physics and a member of the California Association for Astronomical Research (CARA) Board. “During his tenure federal and privately funded cutting edge instruments were built and great advances were made in adaptive optics. We wish him well in his new job.”
Tonight the Moon and Jupiter will be quite close. The pair will rise at nearly the same time, about 17:08HST. The Moon will be very near full, 98% illuminated and about 5° from the bright planet.
When diving with a camera you understand the situation… It is not a question of if you flood the camera, it is a question of when you flood the camera.
The author diving the intake pipes at OTEC, photo by Pete TuckerYes, I flooded a camera this weekend.
Just 15-20ft down on a dive off the old Kona airport, I went to turn the camera on and saw something that made my heart miss a beat. The camera case was half full of water. Nooooo!
As we were just starting the dive I popped to the surface and drained the case. I knew that the damage was already done, salt water and electro-optics simply do not mix. Re-seating the rear hatch I dive again, the leak has stopped.
Continuing the dive without a camera was painful. I dive to shoot, not being able to take photos takes the color out of the dive. At least nothing special wandered by, no 14ft tiger shark or underwater humpback sighting, that would have been excruciating.
The leak appeared to be on the rear hatch, I could see a trickle originating on the top right corner. Some small debris in the seal? A slight kink in seating the seal. Later examination shows nothing wrong, I will probably never know.
The memory card appears to be just fine, I read out the few shots that were on it. This includes the photo of the folks drying coffee on the old runway. I simply marked the card so I know which one it was in case there are questions about the reliability later. The camera battery also appears to have survived the immersion, need to use it a through a couple cycles to be sure.
Otherwise the camera is an expensive desk ornament.
As Pete said after the dive… “Insert $400 to play again.”
Fortunately there is EBay… Inserting a mere $200 has a used G12 on it’s way for me to play again. It appears the the G12 is old enough that used cameras are very available and the prices are falling. I may want to pick up another one. This is why I use a few hundred dollar camera underwater, not a few thousand dollar camera, it will happen again. In the meantime Pete is currently assembling a Canon 5D MkII underwater rig. Not me.
Rigging scuba gear at the old airport park, a nice place for a Saturday morning dive with the guys. Just in front of my vehicle a couple is spreading large tarps on the pavement. Setting up a party pavilion? Then the bags of beans get unloaded… They are drying coffee! The old runway with hot asphalt in the sunlight is a good place, those beans will dry fast!
Only in Hawai’i…
Drying coffee beans in the hot sunlight at Old Airport Park.
A team of scientists led by astronomers at the University of California, Riverside has used NASA’s Hubble Space Telescope and the W. M. Keck Observatory to uncover the long-suspected underlying population of galaxies that produced the bulk of new stars during the universe’s early years.
Galaxy Cluster Abell 1689 Credit: HST/STScI, H. Ford (JHU)The galaxies are the smallest, faintest, and most numerous galaxies ever seen in the remote universe, and were captured by Hubble deep exposures taken in ultraviolet light, and confirmed using the mighty Keck I telescope on the summit of Mauna Kea on the island of Hawaii.
