Astronomy – Page 24 – A Darker View

Mercury at Inferior Conjunction

Today Mercury is passing through inferior conjunction, passing between the Sun and the Earth. This fast moving planet will reappear above the dawn in about a week, rising towards maximum elongation on April 11th.

This is the most favorable dawn apparition of the year, actually the best dawn or evening, with the planet reaching over 27° away from the Sun.

Mercury Events for 2019
Apparition	Date	Elongation	Magnitude
Evening	Feb 27	18.1°E	-0.2
Morning	Apr 11	27.7°W	+0.6
Evening	Jun 23	25.2°E	+0.7
Morning	Aug 9	19.0°W	+0.3
Evening	Oct 20	24.6°E	+0.1
Morning	Nov 28	20.1°W	-0.3
Data from the Mercury Chaser’s Calculator by John Walker

New Moon

Young Moon — A very young moon over Waikoloa

New Moon will occur today at 16:04HST.

Both March 2nd and 9th offer good observing weekends this month. Get out and enjoy the dark!

Red Light

The NexStar 11" setup under a dark sky at Kaʻohe — The NexStar 11″ setup under a dark sky at Kaʻohe

New Moon at Kaʻohe

It was a very nice night, clear dark skies and bright stars.

A usual the club’s dark sky star party was held this month at Kaʻohe. After two months of poor weather I was ready for a good night out with a telescope. A few others were too, and joined the club out in the dark.

Arriving at the site there was a thin cloud deck overhead. With years of experience here I looked up and told Maureen that the clouds would be gone in an hour. It did not even take that long, the clouds dissolved right after sunset, leaving a clear skies before we were finished setting up.

Legislative Rebuff

It appears that every single bill attempting to address Mauna Kea issues is dead, at least for the 2019 session.

The moon rising in partial eclipse over the mauna shadow

March first is a deadline referred to as ‘first decking’ in local legislative lingo. This is the date by which the bill must be in final form to allow review before the final votes. No vote, no crossover, being passed to the opposite chamber, house or senate.

Mercury at Maximum Elongation

An evening conjunction of Mercury, Venus and Jupiter on 30 May, 2013

Today Mercury is passing through maximum elongation, the furthest it will rise above the setting Sun in the evening sky. After today the planet will slide back into the Sun’s glare headed for inferior conjunction on March 14th

This is a modest apparition, with the planet only 18° from the Sun at maximum. The next evening apparition in June is much better, reaching over 25° from the Sun.

Keep it Running

Some equipment around the observatory is thirty or more years old. As you would expect, keeping it running can be a challenge.

A redesigned small signal PCB for an Inland Motor FCU-100-30 amplifier power supply

There are two ways of dealing with this old equipment… Replacing it with something new is the preferred way. When it becomes difficult to locate spare parts, when it breaks down too often, just replace it with new gear. For much of the equipment this is the usual answer and is often a major part of the job.

Some equipment is not so easily replaced. When replacement would require wholesale redesign of a system it becomes more of a challenge. Sometimes the only choice is to keep that old gear running.

This is the case with our servo amplifiers. Twelve amplifiers supply the power that drives the telescope, one amplifier for each motor. Eight amplifiers and motors drive azimuth, four drive elevation. Three hundred and seventy tons moved by twelve relatively small DC motors. While much of the telescope control system was recently replaced, it was decided to keep the old servo amplifiers.

You might notice that these servo amplifiers are just a wee bit critical.

First Quarter

Mauna Kea Rules… Take 2

After last year’s debacle that occurred when trying to introduce administrative rules for public and commercial access to Mauna Kea, the University of Hawaii is back with a heavily revised version.

The United Kingdom Infrared Telescope surrounded by the sunset crowd

How bad were the original version of the rules? In many areas they seemed to be badly thought out, with language far too expansive. Even a cursory reading reveals that the rules were not reviewed by someone familiar with some of the technical language used. Many of the proposed rules would have created safety issues, or even devoid of common sense.

It does appear that they actually listened to the criticism that was received in written form and at the public hearings. Many of the complete gaffes have been removed or reasonably revised.

Full Moon

Full Moon will occur today at 05:53HST.

This full Moon will be a perigee full Moon, with the Moon appearing a bit larger and brighter. Today lunar perigee occurs within 7 hours of full, producing a full moon that is about 12% larger and 30% brighter than if full occurs while the Moon is at apogee.