Observing on Mt.Teide, Tenerife, 5th night

Date: 10./11.10.2015
Time: 20:00-22:00 (local time)
Observing site: Tabonal Negro (2362m), Teide N.P., Tenerife, Spain
Instrument: L80/400mm (3” refractor)

NELM: 6.6
SQM: 21.05-21.34
Darkness of the background sky: 1
Seeing: 2
Transparency: 1
Weather: Clear sky, calm, +13C

Objects observed: NGC 6242, 6281, 6520, 6544

During the fifth and last night of observing during my trip to Tenerife, I drove to yet another different observing spot. During this night I drove to place called Tabonal Negro which is located very near the base of the Peak of Teide at altitude of 2362 meters. I was trying to find a place that would be as far away as possible from any light pollution source, just to see if there are any differences between different observing spots in the Teide caldera.

In this place there was another scenary/viewpoint for tourists which was paved and inteded place for parking cars. Otherwise also this spot was good for observing, but there was heavy traffic during the night and the car headlights were disturbing much. And besides this, there were some people coming to the parking place or leaving it causing severe local light pollution disturbance. So it was practically impossible to observe in peace and solitude as I would like to do. I also noticed that there was not any noticeable difference in observing conditions between this and the other places I went to. It was just as good as the others. Nevertheless, here are the observtions from my last observing night on Mt.Teide:

NGC 6281

NGC 6281 (Hidden treasure 80) is a rather large open cluster in the southern part of Scorpius. It is located just 2,5 degrees east from mu2 Scorpii. Of this object I wrote following notes:

According to Skymap pro 9 this should be a large cluster with diameter of 3 degrees, instead the size of the cluster visually appears to be about 1 degree. The cluster is pretty concentrated. Best visible @ 27x

151010-11_NGC 6281
NGC 6281 observed with 3” refractor

NGC 6242

My next target was yet another open cluster in Scorpius known as NGC 6242 (Hidden treasure 79). This object was located in the vicinity of the previous object, just 1 degree to SSE from mu2 Scorpii. It is a pretty small open cluster. Of this object I wrote following notes:

A small, faint-starred and poor open cluster. Low elevation of the object may have affected the appearance of the object.

151010-11_NGC 6242
NGC 6242 observed with 3” refractor

NGC 6544

The third object of the night was NGC 6544 (Hidden treasure 89), a globular cluster in Sagittarius located just 1 degree from M8 to SE. I wrote following notes of this object:

A small, faint globular cluster, even brightness distribution, not resolved.

151010-11_NGC 6544
NGC 6544 observed with 3” refractor

NGC 6520

And finally as the last but not least object of the night and my whole observing trip I observed NGC 6520 (Hidden treasure 88), which is an open cluster 3 degrees south from M8. Of this object, I wrote following notes:

Small, compact and faint open cluster, mostly visible as a starglow.

151010-11_NGC 6520
NGC 6520 observed with 3” refractor

Final thoughts

So, that was my first observing trip to observing southern deep sky objects not visible from Finland. During the trip, I made in total 27 observations during 5 nights. I noticed, that just in terms of the darkness of the sky, Teide is really good but not extraordinarily good. It is as good as Finland is at it’s best – the best SQM readings on Mt.Teide were about 21.4, which is also the best that I have recorder in Finland. The naked eye limiting magnitude was about 6.6, and I have recorder similar NELM’s also in Finland in very dark places. Of course, Teide still has many very important advantages:

  • darkness all year round (in Finland light summers restrict observing)
  • almost always totally crystal clear sky (in Finland, cloudiness is prevailing)
  • almost always pristine, dark sky (in Finland, the sky is always not so dark, because of light pollution, aurorae, etc)
  • always comfortable temperature for observing (in Finland, it can be bitterly cold in winter)
  • dry air (in Finland air humidity problem is a nuicance every night, especially in Autumn)
  • southern objects well observable (although Magellanic clouds are barely below horizon, southern location is huge advantage in comparison with Finland, where northern location restricts objects available)
  • easy to travel to
  • safe and western

There was one disadvantage though, at least based on my observations: it seems that there is quite a lot of traffic in the roads through the Teide caldera, the car headlights will kill your dark adaptation and disturb observing often. And it is possible, that you cannot observe in peace and solitude. So I would recommend finding an observing spot enough off the main roads where you can observe in peace and solitude.

I’m very happy and grateful that I was able to do this trip! and mostly satisfied with my observations and my results. I hope that this wont be my last observing trip to Mt.Teide! If I will have another chance to travel there to observe, I would focus my observing energy to the objects of Centaurus, Puppis, Vela and Carina.




Observing on Mt.Teide, Tenerife, 4th night

Date: 9./10.10.2015
Time: 20:00-23:00 (local time)
Observing site: Mirador de Chio (2100m), Teide N.P., Tenerife, Spain
Instrument: L80/400mm (3” refractor)

NELM: 6.6
SQM: 20.98-21.30
Darkness of the background sky: 1
Seeing: 2
Transparency: 1
Weather: Clear sky, light wind, +16 – +15 C

Objects observed: NGC 6231, 6400, 6441, 6541, 6723

On the fourth night of my observing trip to Tenerife, I went observing on a different spot. This time I drove further the road to Teide caldera. From the caldera I found a place called Mirador de Chio, which was a scenary/viewpoint for tourists. There was also a good paved place for parking a car and for observing. The only downside of this spot was that it was along a straight road, and whenever a car approached, the headlights of the car were disturbing observing quite much.

And another thing was that I wasn’t the onlyone interested in stargazing – at some point during the night a tourist bus full of apparenty italian tourists stopped by and their guide started giving them a star show in italian! That was interesting in itself, but it was disturbing my observing. During this night I made 5 observations that I publish. Besides this there was also sixth observation, but I’m very uncertain of it, I doubt that I hadn’t even seen the actual object that I was trying to observe. This target was a small reflection nebula 6729 on Sagittarius – Corona australis border.

Anyway, I’ll present my succesfull observations from the fourth night here:

NGC 6231

NGC 6231 (Caldwell 76) is a small and compact open cluster in southern Scorpius, just 30′ north from zeta Scorpii. Of this object, I wrote as follows:

Small, compact and bright-starred open cluster. Pretty nice!

151009-10_NGC 6231
NGC 6231 observed with 3” refractor

NGC 6441

My next target was NGC 6441 (Hidden treasure 86), which is a small globular cluster in the tip of the tail of Scorpius. Of this object I wrote following notes:

Small and faint globular cluster, not resolved, even brightness distribution.

151009-10_NGC 6441
NGC 6441 observed with 3” refractor

NGC 6400

NGC 6400 (Hidden treasure 82) is an open cluster located in the tail of Scorpius, just 1 degree east from lambda Scorpii. I wrote following notes of this object:

A small, faint-starred open cluster, mostly visible as a star glow.

151009-10_NGC 6400
NGC 6400 observed with 3” refractor

NGC 6541

NGC 6541 (Caldwell 78) is a lonely globular cluster in the constellation of Corona australis. Of this object, I wrote following notes:

Rather small, pretty bright globular cluster, gets brighter towards the core, not resolved.

151009-10_NGC 6541
NGC 6541 observed with 3” refractor

NGC 6723

NGC 6723 (Hidden treasure 96) is a globular cluster in southern Saggitarius, just on the Sagittarius-Corona australis border. I wrote following notes of this object:

Rather small and bright open cluster. The cluster has pretty even brightness distribution, not resolved.

151009-10_NGC 6723
NGC 6723 observed with 3” refractor

Observing on Mt.Teide, Tenerife, 3rd night

Date: 8./9.10.2015
Time: 21:30-23:00 (local time)
Observing site: El Retamar (2100m), Teide N.P., Tenerife, Spain
Instrument: L80/400mm (3” refractor)

NELM: 5.7
SQM: 20.93-21.15
Darkness of the background sky: 1
Seeing: 2
Transparency: 2 to 3
Weather: Some high clouds, otherwise clear sky, calm, +12 C

Objects observed: NGC 55, 253, 288, 6624

The third night of my observing trip to Tenerife was the only night when the observing conditios weren’t ideal. During the early night, there were some high clouds in the sky diminishing transparency. But during the night, the clouds drifted away, and the conditions got better. During this night I was observing exactly in the same spot than during the first night. This night it was totally calm and observing was very pleasent. This time I was quite tired though, and I observed only four objects.

NGC 6624

During this night my first object was NGC 6624 (Hidden treasure 91), one of the globular clusters in Sagittarius. This object is located within the Teapot, just 50′ SE from delta Sagittarii. Of this object I wrote as follows:

Small and faint globular cluster, not resolved.

151008-09_NGC 6624
NGC 6624 observed with 3” refractor

NGC 288

NGC 288 (Hidden treasure 4) is a lonely globular cluster in the faint-starred constellation of Sculptor. It could barely be visible from Finland, but it’s easier to observe it from a southern location. This globular cluster is located in the northern part of Sculptor, near the famous galaxy NGC 253, just less than 2 degrees SE from the galaxy. Of this object I wrote as follows:

Small globular cluster, not resolved, pretty even brightness distribution.

151008-09_NGC 288
NGC 288 observed with 3” refractor

NGC 253

My next object was previously mentioned galaxy NGC 253 (Caldwell 65), also known as the Silver Dollar -galaxy in northern part of Sculptor. I have actually observed this already from Finland, but I decided to observe it again because it was near the other targets that were on my list. In Southernmost Finland this object rises just 4 degrees above horizon and it is barely visible. But when I observed it from Mt. Teide, I wrote following notes of it:

Large and bright edge on -galaxy. The long axis of the galaxy is in SW-NE orientation. The galaxy seems to have a little bit mottled appearance.

151008-09_NGC 253
NGC 253 observed with 3” refractor

NGC 55

The last object of the third observing night was NGC 55 (Caldwell 72), yet another galaxy in Sculptor. This galaxy is located in the southernmost part of the constellation, on the Sculptor-Phoenix boundary. Of this object I wrote as follows:

Large and faint edge on -galaxy. Long axis in SW-NE orientation. Visible only with averted vision.

151008-09_NGC 55
NGC 55 observed with 3” refractor

Observing in Tähtikallio Observatory 15./16.9.2012

Date: 15./16.9.2012
Time: 22:00-03:30
Observing site: Tähtikallio observatory, Finland
Instrument: C406/4064mm (16” Catadioptric)

NELM: 6,6
SQM: 21,28
Darkness of the background sky: 2
Seeing: 2
Transparency: 1
Weather: Clear sky, calm, no Moon, +10 °C

Objects observed: Caldwell 30 (NGC 7331) (visual, sketching), Hickson 92 (visual, sketching), Hickson 94 (visual, sketching)

In this session I was able to make some observation and sketching with the 16” Catadioptric telescope of Tähtikallio Observatory in Artjärvi, Finland. This observing session happened during the annual meeting of Finnish deep sky observers.

During this session I observed Caldwell 30 (NGC 7331), which is a nearly edge-on spiral galaxy in Pegasus. Besides this, I observed Hickson 92 and 94, which are faint and challenging groups of galaxies from the Hickson catalogue of compact galaxy groups. Observing conditions were good during the whole session.

Caldwel 30 (NGC 7331): @200x, large and bright, almost edge -on galaxy. The galaxy is very elongated in shape, and it’s length axis is oriented in N-S -direction. The galaxy has an almost stellar core with relatively bright halo that is surrounding it. The brightness of the galaxy decreases rapidly outwards from the core of the galaxy. With instrument like this and this magnification, the galaxy extends almost from the edge of the field to another. It is possible to see hints of EDL west from the core of the galaxy when gazing with averted vision. Of the satellite galaxies of NGC 7331, I was able to see at least NGC 7335. It is visible as a small, fuzzy spot about 3′ to NE from the core of NGC 7331.

Caldwell 30 (NGC 7331) observed with 40'' Catadioptric
Caldwell 30 (NGC 7331) observed with 16” Catadioptric

Hickson 92: @200x, I was able to see four galaxies of this group: NGC 7320 (13,2 mag), NGC 7317 (14,6 mag), NGC 7318B (14,0 mag) and NGC 7318A (14,4 mag). For some reason, I apparently missed NGC 7319 (14,1 mag), which I think, should have been visible with this instrument. All these galaxies were visible as faint, fuzzy nebulas, best visible with averted vision.

Reasons, why I didn’t spot NGC 7319 might be caused by following factors:

-When I was doing this observation, I didn’t have any detailed map of this object. Neither did I have any clear mental map or image of this object in my mind (which on the other hand, is just a good thing).
-I wasn’t alone all the time, and I wasn’t able to focus on the observing as much as I had wanted to
-I hadn’t been obsering with this instrument much before this session
-There might have been some dew on the oculars, and the optical surfaces could have been a little bit dirty

Hickson 92 observed with 40''' Catadioptric
Hickson 92 observed with 16”’ Catadioptric

Hickson 94: @200x, only two galaxies, NGC 7578A (14,9 mag) and 7678B (14,9 mag) of this cluster were clearly visible. Both galaxies appeared as a small, faint, fuzzy nebulas, that were only barely visible with direct gaze, but became better visible with averted vision. Also when comparing my sketch with the SIMBAD photo, it seems that the star-like cores of HCG 94C (16,3 B mag) and D (16,2 B mag) were also visible.

A galaxy cluster Hickson 94 observed and sketched with the 16'' Meade of Tähtikallio in 15./16.9.2012. Only two galaxies (NGC 7578-1, NGC 7578-2) of the cluster were visible.
Hickson 94 observed with 16” Catadioptric