GenPIC Second Code Release

A minor code revision as I slowly get everything working properly. I am adding new modules as I need them for other projects.

GenPIC Processor
The microprocessor on a GenPIC PCB assembly
The latest GenPIC deployed will be a coolant valve controller that allows remote control of some glycol valves in the AO bench. It is a pretty simple device, just four relays with some automatic timing rules and a serial control interface.

In the process I added support for the service connectors including parallel and simple serial modules to the GenPIC code base, may as well release it. Thus you get code release 0.2…

GenPIC Code 0.2

Along with the new modules I removed the copyright notices that I had left in the code, replacing them with a Creative Commons Attribution-ShareAlike 4.0 (CC BY-SA 4.0) license, just something I overlooked when releasing everything as open source.

Next up will probably be SD card support, I have a project that needs to be finished requiring some reasonable data storage. Just ordered a few micro-SD card breakout boards from SparkFun

Unexpected Classification of Exoplanets Discovered

W. M. Keck Observatory press release

Since the mid-1990s, when the first planet around another sun-like star was discovered, astronomers have amassed an ever-expanding collection of nearly 3,500 confirmed exoplanets.

Exoplanet Formation
Assembly Line of Planets: This diagram illustrates how planets are assembled and sorted into two distinct size classes. Image credit: NASA/Kepler/Caltech (R. Hurt)
In a new Caltech-led study, researchers have classified these exoplanets in much the same way that biologists identify new animal species and found the majority of exoplanets fall into two distinct groups: rocky Earth-like planets and larger mini-Neptunes. The team used data from W. M. Keck Observatory and NASA’s Kepler mission.

“This is a major new division in the family tree of planets, analogous to discovering that mammals and lizards are distinct branches on the tree of life,” says Andrew Howard, professor of astronomy at Caltech and a principal investigator of the new research.

The lead author of the new study, to be published in The Astronomical Journal, is Benjamin J. (B. J.) Fulton, a graduate student in Howard’s group.

In essence, their research shows that our galaxy has a strong preference for either rocky planets up to 1.75 times the size of Earth or gas-enshrouded mini-Neptune worlds, which are from 2 to 3.5 times the size of Earth (or somewhat smaller than Neptune). Our galaxy rarely makes planets with sizes in between these two groups.

“Astronomers like to put things in buckets,” says Fulton. “In this case, we have found two very distinct buckets for the majority of the Kepler planets.”

Continue reading “Unexpected Classification of Exoplanets Discovered”

Mercury at Superior Conjunction

Today Mercury will be at superior conjunction. After today the planet will reappear in the evening sky, rising high enough from the Sun’s glow to be seen early next month.

Mercury Transit 9May2016
Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.
Superior conjunction is when the planet passes around the far side of the Sun as seen from Earth. For a few weeks the planet will be lost in the Sun’s glare, hidden from view.

As Mercury is on an orbit inside that of Earth’s it will see both inferior and superior conjunctions as it passes from the evening sky to the dawn sky and back again.

Continue reading “Mercury at Superior Conjunction”

Summer Solstice

Summer solstice occurs today at 18:24HST. 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. Alternately this is the first day of winter for those living south of the equator.

This year many calendars will mark September 21st as the summer solstice, and so it is for much of the world. Here in Hawaiʻi the solstice actually occurs on the 20th when considering the time zone differences.

2017 Solstices and Equinoxes
Perihelion Jan 4 14:18UT Jan 4 04:18HST
Vernal Equinox Mar 20 10:29UT Mar 20 00:29HST
Summer Solstice Jun 21 04:24UT Jun 20 18:24HST
Apehelion Jul 3 20:11UT Jul 3 10:11HST
Autumnal Equinox Sep 22 20:02UT Sep 22 10:02HST
Winter Solstice Dec 21 16:28UT Dec 21 06:28HST
Source: USNO data Services


The Moon and Venus

Tomorrow morning, June 20th, a pretty crescent Moon will be located close to a brilliant Venus. The Moon will be a slim 18% crescent a little under 6° from Venus shining at -4.2 magnitude. The pair will rise about three hours before sunrise at about 2am, look for the two above the brightening glow of dawn.

e Moon, Venus and Aldebaran
The Moon, Venus and Aldebaran join up for an evening conjunction

Astronomers Prove What Separates True Stars from Wannabes

W. M. Keck Observatory press release

Astronomers have shown what separates real stars from the wannabes. Not in Hollywood, but out in the universe.

“When we look up and see the stars shining at night, we are seeing only part of the story,” said Trent Dupuy of the University of Texas at Austin and a graduate of the Institute for Astronomy at the University of Hawaii at Manoa. “Not everything that could be a star ‘makes it,’ and figuring out why this process sometimes fails is just as important as understanding when it succeeds.”

Dupuy is the lead author of the study and is presenting his research today in a news conference at the semi-annual meeting of the American Astronomical Society in Austin.

He and co-author Michael Liu of the University of Hawaii have found that an object must weigh at least 70 times the mass of Jupiter in order to start hydrogen fusion and achieve star-status. If it weighs less, the star does not ignite and becomes a brown dwarf instead.

How did they reach that conclusion? The two studied 31 faint brown dwarf binaries (pairs of these objects that orbit each other) using W. M. Keck Observatory’s laser guide star adaptive optics system (LGS AO) to collect ultra-sharp images of them, and track their orbital motions using high-precision observations.

“We have been working on this since Keck Observatory’s LGS AO first revolutionized ground-based astronomy a decade ago,” said Dupuy. “Keck is the only observatory that has been doing this consistently for over 10 years. That long-running, high-quality data from the laser system is at the core of this project.”

Continue reading “Astronomers Prove What Separates True Stars from Wannabes”


Maintaining the Archive

How do you organize your photos? The answer to that is critical. Anyone who generates a lot of images, and that is just about everyone these days needs to answer that question.

XKCD Photo Library Management
Photo Library Management from XKCD (Randall Munroe, Creative Commons Attribution-NonCommercial 2.5 License.)
Keeping my photo archive organized is a bit of a chore. But skip on the effort and it simply gets worse, to the point of being unusable. If you can not find the photos you need why take photos at all?

The trick is to develop a process and to use it… Religiously. I can not tell you how to do it, I can just tell you how I do it and offer a few suggestions.

There are two basic approaches, simply come up with a way to organize the images into a directory using nothing more than your operating system. The other approach is to use some form of photo organizing software to aid in the task. I do make a large assumption here, that the images are in digital format, not negatives and slides. For that you will have to look elsewhere for answers.

Continue reading “Maintaining the Archive”

Saturn at Opposition

Today the planet Saturn will pass through opposition, directly opposite the Sun in our sky.

Saturn 22Apr2010
Saturn with Titan above
Saturn orbits the Sun once every 29.45 years. As the ringed planet continues on its way the Earth swings around much faster on our inside track. As a result we lap Saturn once every 378.1 days, passing between the planet and the Sun. During opposition Saturn will be well placed for observation all night long, rising at sunset, transiting at midnight, and setting at sunrise.

During opposition the planet and rings will be slightly brighter than normal, an effect known as the opposition effect. The effect is most notable in the rings where the apparent brightness can increase by 30%. The effect is a combination of two factors, shadow hiding and the retro-reflective properties of the ring particles.