Monthly Archives: August 2013

Finding the Little Dipper

Finding Polaris is often easy even though it’s not the brightest star in the northern sky. It is moderately bright (mag 2) and stands out because it’s more or less by itself. If the Big Dipper is visible then Polaris can be found using the two stars of the pouring side of the Big Dipper which point to Polaris. Finding the Little Dipper however is quite a bit more challenging. […]

Observing Report – 2013-08-17

With the main scope in storage, i setup the 70mm Pronto and camera tripod on the front porch and spent an hour looking around. The moon was 11.5days old and 94% illuminated so was washing out the sky quite a bit. Worse was that the objects i wanted to find were near the Milky Way and close to the moon.

I observed between 9:15 and 10:15 which was between nautical twilight and astronomical twilight. With the moon so bright, the sky wasn’t going to get any darker after nautical twilight.

I concentrated on the objects i listed in the August highlights although with the moon so bright my expectations were low. I used either the 24mm Hyperion (20x, FoV 3°23′) eyepiece or the 5mm Hyperion (96x, FoV 42′).

Observing list:

  • Saturn – low in the west. With the 24mm EP (20x)i could tell it was Saturn. With the 5mm (96x) the rings were visible but no details.
  • Double Double – Using the 24mm EP (20x) i could easily see the two pairs. Switching to the 5mm (96x, FoV 42′) both pairs still fit in the same FoV. I could just see the gap between ε2a and ε2b. I could not actually separate ε1 but it was elongated in the correct orientation so it was obviously a double system.
  • M13 – Hercules Cluster was bright and large even with the 24mm EP
  • M92 – Was not visible at 9:15 but by 10pm i could make it out. It was quite small and faint in the 24mm.
  • M57 – At 10:15 i could just find it. With the 24mm it appeared star like albeit a tad fuzzy. With the 5mm (96x) i could just tell that it was a ring.
  • M22 – Very small and faint and only really detectable with averted vision.
  • M20 and M8 – could not find them.
  • M7 – Ptolemy’s Cluster stood out crisply against the rather bright sky. It all fit in the 24mm FoV (20x, FoV 3°23′). At altitude 9° it was just above the tree line.
  • Moon – scanned around a bit. Looked for Vallis Alpes but could not find it.

Solar Observing – Kanata Chapters at 2013-08-18 2pm EDT

The Ottawa chapter of the RASC is hosting a public sidewalk Solar Observing event on Sunday August 18th, 2013 at 2pm EDT. The event will take place in front of the Kanata Chapters store located in the Centrum plaza by the Hwy #417 and Terry Fox. This is a free event for the general public.

Never look at the sun directly. When observing the sun use only equipment and techniques designed specifically for solar observing. If in doubt, don’t do it!

Construction Continues into August

With June and July being too hot with late sunsets, it was decided to finally construct a concrete pier for the telescope. The tripod was ok as it was positioned on a concrete pad, but sill lost alignment easily. That and the tripod legs took up too much room and it was too high. So the telescope was dismantled and put in storage and the pier project got underway. However, 8 weeks later and the pier has not yet appeared.

The design is complete as is the metal pier top adapter. This week work has started in earnest on the actual pier with the expectation that the observatory will be up and running in a couple of weeks. Just in time for the dark phase of the moon which allows for imaging sessions with the DSLR.

The Sky for August 2013

Now that we are into August astronomical twilight starts at about 10pm EDT with dawn is around 4am EDT. This means being able to get outside to see some interesting stuff before bedtime and ample time to set up an imaging run. Identifying constellations and locating bright stars can be done shortly after nautical twilight which starts about 9:15pm EDT. Finder_Chart-Sagittarius_2013-08-17

The main feature of the sky in August and September is the Milky Way. In August it’s due south at 10pm with the brightest section – the Ophiuchus bulge – quite prominent. If observing for a moderately dark site, look for the dark  lane that runs down the middle.

Sagittarius is due south near the horizon. The galactic centre is about 1° south of 3 Sagittarii. Look there and you are looking at the “black hole” that lies at the centre of our galaxy.

This section of the milky way has several excellent binocular or small telescope targets. Using binoculars or a small scope, just scan up the Milky Way and you will see several interesting fuzzy objects (also known as deep sky objects – DSOs). A few noteworthy objects to look for are:

  • Lagoon Nebula (M8) – can sometimes be seen unaided. A small telescope will reveal a very bright patch with some dark lanes.
  • Trifid Nebula (M20) – Physically connected to M8, it’s a little harder to see due to its red colour. Look for the open cluster M21 just a little to the north east in the same binocular FoV.
  • Sagittarius Cluster (M22) – a mag 6.5 globular cluster which ranks as the third brightest in the sky.

Finder_Chart-Zenith_2013-08-17 At the zenith three easy to identify constellations stretch from east to west – Cygnus, Lyra and Hercules. Don’t forget to look for Delphinus (the Dolphin) – the small diamond shaped constellation near the ecliptic.

Hercules is home to two of the brightest globular clusters – The Hercules Cluster (M13) and M92. M13 is mag 7 and large enough to be seen unaided from a dark sky (limiting mag 5+). M92 will require binoculars.

Finder_Chart_Lyra The Ring Nebula (M57) is located in the south part of Lyra and is an excellent planetary nebula to view in small scopes. It’s only mag 9.5 so requires fairly dark skies, But at 1.7′ across, it’s large for a planetary nebula.

Just to the east of Vega in Lyra is Epsilon Lyra (ε) the “double double” – a multiple star system consisting of 4 stars arranged in two pairs.

The two pairs have a separation of 3.5′ which can be seen in binoculars. The pairs have separations of 1.3″ and 2.3″ making them challenging doubles to split in a 4″ scope. However, the two pairs are oriented 90° with respect to each other making it easy to compare the star shapes and aiding in detecting the separation.

Observing in June and July

June and July tend to be a bust for astronomy. At least for visual observing and astrophotography with a DSLR. The skies don’t get really dark at the observatory until a little after 11pm or even 11:30pm and the warm nights make imaging with an uncooled camera challenging. […]

Observation Report – Perseids Meteor Shower – 2013-08-12 3am EDT

I observed the Perseids Meteor shower between 3:15am EDT and 4:00am on the morning of Monday August 12th, 2013. I saw a couple dozen perseids and a few sporadics in that time – i didn’t keep track as i was just casually observing. There was also one quite bright meteor of maybe magnitude -3.

The forecasted best time to view the Perseids Meteor shower this year was either Aug 12th or 13th in the early morning hours. However, the Perseids seem to have a very broad peak so viewing the skies a few days before of after the predicted peak still resulted in a significant number of meteors observed.

For my location, it was clear on Friday August 9th but i didn’t make it out to observe. Colleagues reported a significant rates of about 40 an hour that night. Saturday night was cloudy but Sunday night started out cloudy and cleared in the early hours of Monday August 12th. As it happens, i woke up at 3am and was pleasantly surprised to a very clear and transparent sky. So i decided to go outside and see some perseids.

I setup my lawn chair in the yard and observed the shower for about 45min – from 3:15am edt to about 4am. The skies were mag 4.8 at the zenith (Upsilon1 Cass). I could see about to 20deg in the south west. North was trees and north-east has a large city lighting up the sky. The milky way stretched from east to west across the zenith. The Andromeda galaxy was easily visible without a telescope.

Immediately i say about a half dozen perseids in the couple minutes – about 2 per min. One was a probably mag -3 (just guessing) which lit up a path of almost 60deg of the sky in the south west and was visible for 3-4 sec after it past – quite bright. Several others were also bright but many were short and dim. The rates were sporadic. Sometimes several min between observations.

In all i probably saw 30 meteors in the 45min i observed.