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Detailed observing report deepsky, moon, Venus and Jupiter

On Monday the 22nd of February I had a marathon observing session. I started with Venus and the Moon at 5 pm (UT), then did some deepsky observing, and ended with Jupiter at 4 am (UT) the next morning. I did all the observing from my backyard, using the 8-inch Klevtzov-Cassegrain on equatorial mount. Here is a detailed report with some digital pics of

the Moon (and Venus) and Jupiter, and some sketches of some double stars, a galaxy and a carbon star. Enjoy!

Venus and The Moon
At 5 pm the Moon and Venus could be seen very high in the south-western sky. It was wonderful to see these two bright objects together. Here’s a picture to give you an impression.


In the next two months Venus will climb higher and higher. In the second half of March and the first half of April, all the five brightest planets will be visible at the same time. Then Venus will be lined up along the ecliptic together with Mercury, Mars, Jupiter and Saturn. In June Venus will transit the Sun for the first time since 1882. So keep an eye on this bright planet in the next few months!  After I set up my telescope I had a closer look at the Moon.


As you can see, Mare Crisium lay on the terminator. Above mare Crisium you can see the outlines of Cleomedes. Mare Humboldtianum and Mare Marginis are also visible. To the south of Mare Crisium we can see Langrenus, Vendelinus (and Lame), Petavius (and Vallis Palitschz) and Furnerius. I only pointed out the bigger features. Using the Rukl Moon Atlas you can detect many more!

The Deepsky
About 7pm (UT) the Moon had disappeared and it was time for a night of deepsky observing. To warm up I first visited a few “old friends” like the Pleiades, M 42, Orion’s Belt, M 44, and M 35. After that I started to hunt down a few new objects, 3 double stars, a galaxy, 3 globular clusters and a carbon star. I sketched the field of view of the double stars and the carbon star, to verify them next day (just to be sure it where the one’s I was looking for). I also made a sketch of the galaxy and it’s surrounding star-field, to see if I got the orientation and its size right. The sketches are all included in this report.

1. Zeta Cancri
This is a triple star in Cancer. I could only detect split two components (already at 100x). I could not split the AB pair. They have a separation of 0.8”, while the AB and C components are separated by 5.7”. The colour of both components was yellow. They are easy to locate. In Gemini, go from Castor to Pollux and extend this line with two times the same length. Then you are in the area of Zeta Cancri. With its distinct colour, you cannot miss it.

Zeta Cancri, 133x, FOV 22’

2. Iota Cancri
This one is also easy to locate, Just have a look in your star atlas at the constellation of Cancer. There is one line of the constellation that stretches north, passing M 44. At the end of this line you will find Iota Cancri. I never had seen it before, but when my telescope came across it, using a 62.5 magnification I was stunned. It almost looks like Albireo, a bright yellow, accompanied by a somewhat fainter blue star.

Iota Cancri, 62x FOV 47’

3. Algieba (Gamma Leonis)
This wonderful double star lies at the centre of “the Sickle” in the constellation of Leo, 8 degrees north-northeast of Regulus (Alpha Leonis). Both companions are bright yellow, with magnitudes of 2.2 and 3.5. the separation is 4.4”. The B component lies in a position angle of 127 degrees.

Algieba, 133x, FOV 22’

4. NGC 2903
From my backyard, which is heavily light polluted, I cannot see too much galaxies. In an article in sky and telescope I read that NGC 2903 was even brighter than M 65 and M66, but for an unknown reason was not included in the Messier catalogue. I decided to go for it. Again, this object is easy tot locate, because there are some bright stars in the Lion’s head that will guide you to NGC 2903. In the lion’s head, locate 17 Epsilon Leonis. From there go about three degrees to the west to 4 Lambda Leonis. NGC 2903 lies only 2 degrees south of this star.

I immediately spotted the galaxies bright core, without averted vision. Using averted vision it showed up as an elongated, faint smudge of light. Apart from the bright core, I could not detect any details. Later, when comparing my sketch with my sky atlas, I noted that it was even bigger. The two stars south of this galaxy, actually lie right near the southern tip of NGC 2903.

NGC 2903, 100x, FOV 29’

5. M 53, M 3 and M 13
Now it was time for some globular clusters. First I had a look at M 53, which lies only 1 degree to the north-west of Alpha Coma Berenices. With the 8-inch telescope at 80x I only saw it as a nebulous smudge of light. At 166x I could partially resolve the stars around the edges of the cluster, but I had to use averted vision to do so.

Next on the list was M 3, lying about halfway between Arcturus in Bootes and Cor Caroli in Canes Venatici. You immediately see the difference with M 53. M 3 is a big bright globular cluster. At 100x I already resolved stars on the edges of the cluster. When using averted vision, it became even bigger and brighter. At 166x to 200x, individual stars could be seen almost to the middle of the cluster. Now it was time for M 13.

M 13 is the best (in the northern hemisphere). It is located in Hercules, halfway between Zeta and Eta Herculis in “the Keystone”. At 100x I could detect some arms (or chains) of stars coming out of the cluster. At 166 it looks like a giant spider. The cluster is resolved right to the middle, but there is a glow of many more unresolved stars.

My advice, view at these three globulars in the same order I did. The views get better and better this way!

6. La Superba
In Canes Venatici lies La Superba ( Y Canum Venaticorum, variable star), a carbon Star. Carbon stars are cool red giants with a lot of carbon molecules in their atmosphere, causing absorption of blue light. That’s why these stars look “deep red”. La Superba again is easy to spot. From 12 Alpha Canum Venaticorum ( Cor Carolis) go to 8 beta Canum Venaticorum (Chara). From Chara go about north-northeast. There you will find the “red” star. At 100x there where only four other stars in the field of view (about 30’wink. The limiting magnitude was about 12 to 12.5 at that moment. The colour was deep orange at the moment. It really stood out from its surroundings.

La Superba, 100x, FOV 29’

I ended my night around 4am with a quick look at Jupiter. All four moons stood to one site of the planet. Here’s an image that should give you an idea. Io is closest to Jupiter but very hard to detect on the image. It had been a great night of observing.


Posted by Math on 02/27 at 06:49 AM
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