Monthly Archives: October 2014

Super Moon 2014-09-09

A “super moon” occurs when the moon is full (or new) and is also at it’s closest approach to the Earth (perigee). When this happens, the full moon appears bigger and brighter compared to other full moons. The difference in size is only 16% compared to the smallest full moon – a full moon at apogee or micro moon. So it’s actually very hard to notice the larger apparent size unless you see the super moon presented beside the micro moon.

While i don’t like the term “Super Moon” the media has latched onto it, so that’s what i’ve call this post. The correct term according to wikipedia is “perigee-syzygy of the Earth-Moon-Sun”. Ok, doesn’t roll off the tongue very well. But a simpler term is “perigee moon”. Perigee meaning the point where the moon is closest to earth during it’s monthly orbit. Both a full moon and new moon at perigee are considered a “super moon”, but the media doesn’t seem to care about the new moon event. (At new moon you can’t actually see the moon since it’s directly in line with the sun.)

When a full moon or new moon occurs, the sun, earth and moon are aligned so their mutual gravitational forces are also aligned and the combined affect on the earth’s oceans is at it’s greatest. At perigee the moon’s gravitational pull on the earth is also at a maximum. So the combined affect of the sun and the super moon can have a mild affect on tides. And if a perigee moon occurs in spring when tides are already at their highest, the additional affects of a perigee moon can be noticeable.

It’s always reported in the media that the perigee full moon makes the tides higher. But it occurs to me that at full moon, the moon and sun are on opposite sides of the earth. So it would seem their gravitational pull on the oceans should cancel out and the tides would therefore be smaller. I don’t know if this is the case however.

Usually there are 2, and occasionally just one perigee moon in a calendar year. The coincidence of full moon with perigee occurs every 13.94 months. The new moons before and after the full moon can also be at perigee so it’s possible to have 3 super moons in one calendar year. This occurred in 2014 with super moons on July 12th, August 10th, and Sept. 9th.

On September 8th, i took a photograph of the almost full moon just around sunset – or moon rise.

Super Moon 2014-09-07

Super Moon 2014-09-07

The next day was actually the super moon event and i took this photo:

Moon - Super Moon 2014-09-08 v2

Moon – Super Moon 2014-09-08 v2

M81-M82 – Bodes Nebula – 2014-04-24

The data for this image was collected in April but i didn’t get around to processing the image until last week. I was working through a new image processing workflow based on PixInsight. It didn’t really take 6 months to develop the process, it just took that long for me to get around to it.

Bode’s Nebula is in the constellation Ursa Major, and therefore towards the north. Until last year when the trees to the north came down, this target was out of view.

The data was aquired over three nights. However, there were a lot of technical problems (and operator error) so only 2 of the three nights produced usable results. And then only a partial set of the data from the other two nights was acceptable. Still, there is 5hrs of integration time which is enough to produce a reasonable image.

M81 (NGC 3031) Bode’s Galaxy
Face-on spiral galaxy in Ursa Major
Dimensions: 26.9 x 14.1 arc-min
Magnitude: 6.94
Distance: 11.8 mLy

M82 (NGC 3034) Cigar Galaxy
Edge-on spiral galaxy in Ursa Major
Dimensions: 11.2 x 4.3 arc-min
Magnitude: 8.41
Distance: 11.4-12.4 mLy

M81-M82 - Bodes Nebula - 2014-04-24

M81-M82 – Bodes Nebula – 2014-04-24

The bright star in the upper middle of M82 is a supernova SN 2014J which appeared 2014-01-21 at 19.20 UT. A close crop with an annotated view shows the location of the super nova.

M82 -SN 2014J - 2014-04-24

M82 -SN 2014J – 2014-04-24

NGC6946 – Fireworks Galaxy 2014-09-26 v2

The Fireworks Galaxy is technically in the constellation Cygnus, but it is quite a bit to the north. Until the trees were removed last year that obsecured the northern sky, circum polar objects were out of view.

NGC 6946 (Arp 29, Caldwell 12) – The Fireworks Galaxy.
Dimensions: 11.5 x 9.8 arcmin
Magnitude: 9.6
Distance: 22.5Mly (+/- 8Mly)

NGC 6946 - Fireworks Galaxy - 2014-09-26 v2

NGC 6946 – Fireworks Galaxy – 2014-09-26 v2

The data for the image was collected over three nights from Oct 24 to the 26th. Amazingly there were 3 clear night in a row all with good seeing. The total integration time is 15hrs which is a bit of a record for me.