SPOTTING THE LANDING SITE OF CHANDRAYAAN 2

As the landing date for the Chandrayaan 2 approaches which is on 7th September  it is curious on where it is going to land. Amateur Astronomers who keep observing the celestial objects are more curious and would love to know the position of landing so that they can spot the landing area on the moon with their telescopes. Most of the craters are visible with small telescopes and there are lot of maps that are available online to spot the craters.

About the craters Manzinus C and Simpelius N

ISRO sources say that the landing site will be between craters Manzinus C and Simpelius N on the high lands between them. As amateurs will know the letters next to the crater names says that these are smaller craters around the big crater. Here Manzinus is a big crater with a diameter close to 100 km diameter and smaller craters near its vicinity are given capital letters for example Manzinus crater has Manzinus C, Manzinus D, Manzinus G, Manzinus E etc,. This is same with all craters, so Simpelius N is a small crater close to Simpelius crater which is close to 70km in diameter.

Locating the Landing site of Chandrayaan 2

To find the crater its good to start with the best known bright crater on the south side of the moon, the Tycho crater. After finding Tycho, the next hop is to near by crater Magnius, this is also easy to find because of the size of the crater, the Magnius crater is close to 160km in diameter. Next hop is to Crater Zach which is also easy to find due its appearance. Continuing in the same line to almost limb of the moon the landing sites of Chandarayaan 2 can be found, the craters Manzinus C and Simpelius N. Crater Manzinus C is easy to find because of the diameter it has, close to 20km, but the Simpelius N is little challenging at 8km diameter.

Location of Chandrayaan 2 Landing Site

Best time to Spot the Landing site of Chandrayaan 2

To attempt to spot the craters Sun has to light it up, as I am writing this article on 21st of August the craters are in the dark, the next chance will come on 6th September, when moon is half lit and the craters will be easy to spot until 17th of September. For future reference the craters are best seen from half moon after new moon to 3 days after full moon. Happy Spotting.

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Mercury in the evening Sky

In the evening sky, low in the horizon, if we carefully look we can find the smallest planet in our solar system. After sunset, in a place where there are no obstruction like buildings or trees, in this unobstructed view of the western horizon we can spot planet mercury. Since mercury orbits close to the sun we can only find the planets close to the horizon in evening or morning skies.

During its orbit around the sun there are two favorable points where we can observe the planet. This is the maximum separation of angle between Sun and planet. This point of maximum separation is called Greatest elongation. For planet mercury this greatest elongation angle is between 18 degrees to 28 degrees. This is the reason why most people miss the planet, since it is so close to horizon.

On November 6^th the planet will reach greatest elongation giving us a good opportunity to catch a glimpse of this planet with naked eye, binoculars and telescopes. The angle for this elongation is 23 degrees, this means just after sunset the planet will be 23degrees above western horizon.

Spot planet after sunset in western sky.

The planet will be at a magnitude of -0.2, although it is bright the drawback is that it is immersed in twilight making it difficult to spot but as twilight fades its easy to spot.

With a telescope we can see the gibbous phase of mercury with an angular size of 6min of arc. The planet will be in half phase on 11^th of November and from there on the illuminated side of mercury will start decreasing. This is a nice time to see and enjoy and also understand the phases and orbit of mercury. Since the planet is coming closer to earth the angular size will keep increasing and it will be 9mins of arc before the planet sinks into the glare of the sun and then reach inferior conjunction on 27^th of November.

Clear Skies.

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Watch Brightest Venus on Friday

After Sunset in the western twilight sky we see a bright star outshining all the starts in the evening sky, this is the planet Venus. The visual apparent magnitude of the planet Venus is now -4.6 and the apparent magnitude of brightest star in the night sky, Sirius, in the constellation of Cains Major is -1.46 this makes Venus 18 times brighter than Sirius. 

Brocken Inaglory, Venus-pacific-levelled, CC BY-SA 3.0

On February 17th Venus will reach its brightest crescent phase and this is called Greatest Illuminated Extent, the amount of illuminated crescent and the angular diameter of the planet Venus. Venus will have an angular diameter of 39 arc seconds and fraction of illumination is .273 of the angular diameter. After this day the illuminated side will start decreasing and we will see the crescent getting thinner. By second week of March the illuminated fraction will be only .085 of the diameter of the planet and magnitude would have come down to -4.4 still brightest in the evening sky. 

View Through the Telescope on 17th of Feb

View Through the Telescope on 10th March

The planet Venus will slowly fade into glare of the Sun and will reach inferior conjunction on March 25^th. In April we will see Venus in early morning sky before sunrise and again the Greatest Illuminated Extent will happen on April 30^th. Time to take out the telescopes and observe Venus in coming days, if you don't have one you are always welcome at ABAA on Sundays evening and see the Venus through our telescope. Venus sets at 9pm now and in middle of March the planet will set at 7:30pm.

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