Lunar eclispe from Mercury

We all have recently seen the century's longest Total Lunar Eclipse on 27 July this year. In total lunar eclipse moon turns red. Because, very small amount of light bend through earth's atmosphere and fall on moon. It's very beautiful and amazing phenomenon. What if we see Lunar Eclipse from a place other than earth! 

Yes, scientist has done that. In 2014 a lunar eclipse happened in October was seen by MESSENGER probe. This probe was orbiting around mercury planet. Here it's a GIF image. Here, Earth is bright star and moon a small star is disappearing into its shadow. It's really wonderful to see eclipse from such a distance. From earth we see hide and seek of Galilean satellites  (Jupiter's moons) but we can not see it's moon disappearing into Jupiter's shadow. With advance technology now we can see many things which we could not see from earth. 

MESSENGER mission was ended in April 2015 when NASA deliberately crashes probe on Mercury.

 

Earth at left bright star and Moon is disappearing into shadow, MESSENGER probe was at 107 million kilometers from the Earth at the time of eclipse. Source: NASA/Planetary society

Planets, Opposition and Retrograde motion

Last year season of sky watching went without any visible planet in evening sky. So, last year I spent nights watching deep sky objects like star clusters, Galaxies and nebulae. These objects are interesting and have importance in sky watching. But with telescope in hand anyone would like to watch planets. There are seven planets in our sky and in these seven planets we can observe five without help of any optical aid. These five planets are very interesting. If you have any small telescope you can observe changes on them. Mercury and Venus shows phases like Moon. On mars surface you can observe changes like dust storms and shrinking and expansion of polar cap. Jupiter shows very dynamic features on its gaseous surface. Saturn with its beautiful ring display magnificent sight in telescope.

Last year we missed them from our evening and night sky. But from last some months they are making their presence in our sky again. From Last few months Venus is stunningly bright in west horizon after sunset. In may month Jupiter was in opposition and then on 27 June Saturn was in opposition. At the end of this month on 27 July Mars is also going to be in opposition. So month by month they are making their presence and some of them are also getting closer to earth on opposition in their orbit.

Opposition is very interesting alignment of planets and it's also provide great opportunity for sky observers to see planets. At this position planets come at exactly opposite to Sun and Earth in their orbit. When planet comes at this position they rise at sunset and set at sunrise which means they stay maximum time in earth's sky. In case of Jupiter you observe its maximum surface as its day is only of 10 hours. At opposition planets reflects maximum light so appear bright at this position. Opposition is condition at which planets comes directly opposite side of Sun and Earth in their orbit. This condition applied to the Superior planets means planets beyond earth orbit like Mars, Jupiter, Saturn, Uranus and Neptune.

Different alignments of planets with respect to Earth

Different kind of alignment happen with the inferior planets which are located in between earth and sun which are Mercury and Venus. They never comes to opposition. In their case when they comes in between sun and earth its called as Inferior conjunction. At inferior conjunction if they come in plane of Sun and Earth we can see then travelling on Sun disc, its called as Transit. When they Go beyond Sun its called as superior conjunction and we can not see them as they are located exactly beyond Sun. In superior planets condition its called as conjunction. For seeing maximum part of inferior planet they must go far from sun in their orbits. This is called as planets elongation from sun. When they get maximum far from sun its called as planets Maximum or Greatest Elongation from sun. At this greatest elongation inferior planets visible in sky for more time before sunrise or after sunset. 

Unlike stars planets stays in motion constantly. Apart from these conditions planets also sometimes shows retrograde motion. Planets shows motions like direct which is their regular motion in sky which is toward east (there is daily motion of planet also in which they move from east to west, this happens due to earth's rotation on it axis). Sometimes they stop and start moving westward and again stops and then again picked their regular motion. Jupiter was in retrograde motion from 9th March and it ended on 11 July this month. Retrograde motion appears when Earth in her orbit passes other planets in their respected orbit. From earth, observer see that planet is moving backward which is east to west and then again start its direct motion which is west to east. Retrograde motion is long time motion. Planet keep moving in this motion for several days. Its very interesting to observe planets such motions. In 2003 Mars showed retrograde motion which I observed, it was great experience to observe planet moving background of stars. Mars was moving notably quick. Observing planet at different alignments and motions give clear picture that how all these planets with earth move around sun that what Copernicus and Galileo said. So, keep eye on planets for next few months.

Retrograde motion of planet Mars in 2003 as seen from Earth

Note:Images are taken from various internet sources

Telescope, Jupiter and Sketching

My father gave me first telescope when I pass 12 grade. Actually we went to buy a binocular but we ended up in purchasing telescope. It was good deal in binocular budget. My new telescope was 90mm reflector telescope. I was very much excited to see through it. First light descended in my telescope from heaven was the light of Jupiter. The greatest planet in our solar system. It was stunning view of planet Jupiter. The bright yellow disc with brown and orange belts on it. Two belts on equator region was very prominent. It was much like of cricket ball with seam. Then there were four bright lights specs from some distance of this Jupiter disc all align in equatorial plane. These four light specs were four Galilean satellites. This was permanently imprinted in my memory. It was my first observation. On that day planet Jupiter gave me very encouraging picture of upcoming telescopic observation.

After Moon I find Jupiter is the most promising candidate for the telescopic observation. It is big and shows observable features on its discs. These features included it's equatorial belts, polar region belts, great red spot and many storm like features. Jupiter is gaseous giant planet so it's features keep changing and always shows us something new. It's four satellites displays eclipse show. Every thing happens near Jupiter is very rapidly so we can see changes in one night only.

Jupiter through telescope, Image taken by my friend Ashish Sharma with telescope and mobile camera combination

Now when you have telescope then you should also take down your own observation from it. For long time I only used to observe objects through telescope I was not having idea how to record my observations. Then I found book for beginner observer, 'the Sky' written by David Levy. This book become holy book for me. Levy has given many techniques to record observation. When I started recording my observations I preferred to draw objects like old time sky observers rather than taking photographs. I did this because drawing can develop observation skills. Capturing direct image with camera can not give always good observations as most of the times one can get image with blur lines. Drawing does not required great skill or knowledge of art. One can just start doing it and he/she goes on improving in it.

Galileo's sketches of Jupiter, I wondered how he manage to do such nice sketches of Jupiter with four satellites through his crude telescope, Image source, Internet

Jupiter is good to draw but it is challenging too. Jupiter day is less than 10 hours, means everything on Jupiter rotate very fast and scenario changes rapidly. So, you get very few minutes to draw it. If you take much time then picture at Jupiter region change. Due to such fast rotation Jupiter has pressed at polar region and slightly expanded at equatorial region. Jupiter looks oblate in shape due to this. There are features on Jupiter like equatorial belts, in between these belts there are bright belts are called as zones and these belts and zones are disturbed by festoons and bridges.

Jupiter sketch by me, we can see its moon Io at left edge of Jupiter and its shadow on Jupiter, Upperside I sketched Jupiter and its four moons

I take 5 to 10 minutes to look at details appearing on Jupiter surface and after that I sketch it. First I sketch outlines and then fill details in it. One can observe many detail on disc with bigger telescopes. I did most of the observation with the 90 mm telescope so for me it is easy to observe features on Jupiter's equatorial region, at polar region I can not observe much. Even colors are difficult to identify. I started to use color pencils for drawing but after sometime I realizes that it is not giving correct picture of actual observation so I stopped to use color pencil. I now use just pencil with 2HB or 4HB. For color I just write the color of band. Observing planets also required good sky conditions.

When I see my old observations and recent ones I can see how my observation has improved my sketching and details. Every time I look at Jupiter, it shows me new scenarios. Sometimes his belt disappears, new storm appear on it, its moons plays hide and seek around it, also one can see moons shadows marching on it. What else one observer wanted to see. 

Jupiter Sketch by me, we can see Great Red Spot a storm on upper center of sketch