Zain Ahmed of Karachi Astronomers Society called me and a few other members of KaAS this weekend over at the FFO (The Fifth Floor Observatory; the name given to Zain Ahmed’s apartment rooftop). None of the other members could make as they had other priorities. I, however, was craving some astronomy-action so I headed up there!
A Night of Intellectual Discussions
On 1st of April, we had initially decided to take the Sky-Watcher 100ED Telescope out for observation of Saturn – but it was quite late by the time I reached the FFO, and also both of us had some commitments for the Saturday morning. Thus, instead of doing observations, we sat down to casually discuss astronomy and our various plans for the coming days.
I was told that a small group of KaAS members were going on another Rutjuga (Dark Sky Party) to Pir Bhambol, in rural Baluchistan on Saturday (2nd April). While I am writing this (3rd April), they should soon be making their return trip.
Back to our discussion; the need to instigate more and more public interest in astronomy was stressed upon. This year, KaAS has managed to arrange just 1 or 2 events for the general public; and as many as 4 private (members only) events so far! In the coming weekends, (IA) we shall be shifting our focus more towards enlightening the public and trying to arrange as many free and/or public sessions as possible.
Then the topic turned to The Moon and all the various aspects of it. First, the lunar crescent came under ‘inspection’ as there is an extremely thin new crescent moon (24 hours since birth) on 4th April. Conditions-willing it should be sight-able from Karachi.
Now then, I was curious… who holds the record for sighting the youngest new crescent Moon? The answer: http://www.icoproject.org/icop/grecord.html
A really interesting and valid point was raised by Zain Ahmed at this juncture; why do we call it a new Moon? See this:
A new Moon should technically only be a new Moon if the crescent shape from the last lunar cycle has vanished completely. This would only be true in case of a solar eclipse by the Moon! However we know that there is no such thing as monthly solar eclipses because Moon’s orbit is slightly tilted on its axis. In other words, it ‘misses’ the Sun by a few degrees every month, thereby not causing an eclipse and hence retaining the crescent shape (which gets misplaced onto the other side when there is a so called ‘new’ Moon)
(See: http://en.wikipedia.org/wiki/File:Lunar_eclipse_diagram-en.svg)
Moving on; I had with me a copy of the book ‘Bad Astronomy’ by Philip Plait. I was skimming through it, searching for a topic of discussion while simultaneously talking to Zain Ahmed. As you all may be aware of the recent SuperMoon occurrence, which was just Moon making a close pass to the Earth. Did you know that as many as 2 to 3 closer passes happened just in the past 10 years alone? And there is another SuperMoon just next year. Don’t worry; the world is not due to be blown to a pulp just yet!
But close passes of the Moon do, of course, have an increased gravitational effect on the Earth. According to the book I just mentioned, the Moon, on average displaces the Earth (and therefore, you) by as much as 0.3 meter every day! You don’t feel it, because it is a very slow and gentle process. But know that even right now, the Earth beneath you is moving constantly under the gravitational effect of the Moon.
Furthermore, it’s not just the Earth that gets affected. Let us not forget that the Moon itself is an object in space and therefore subject to gravity from the Earth. Take a look at this picture:
Do you see the dark regions in the left picture? That is the side of the Moon that you see, and it is always facing the Earth. The dark regions are Maria, or areas where molten lava once flowed but is now cooled down.
Now in the same picture, notice what is odd about the far side of the Moon. This is the area that is constantly facing away from the Earth. The odd thing is the absence of Maria (or lava flow) on the far side. Why the absence? Because lava is a flowing substance and liquids are affected by gravity. Earth’s gravitational pull has in fact displaced the entire core of our natural satellite towards itself, causing all the lava to shift on the near side!
Amazing enough for you?
That was primarily the gist of our conversation on lunar topography :-)
I stressed that a means of reaching out to the public using the Internet should be present. This would allow us to cover the ‘theoretical’ part of Astronomy that largely gets ignored during Public observation sessions. To counter this problem I have decided to start an astronomy podcast, the first ever in Pakistan. You shall see it very soon (And there will be an Urdu version too!)
A Night of Observations
The scope could not be availed due to time constrains on the first day; so I showed up yet again on Saturday (You simply cannot miss out on the views through a 100ED refractor). The transparency was not too great for much deep sky viewing, so we shifted our focus to Saturn and the stars instead.
First up, the double stars. For those who don’t know, the sky is teeming with stars that appear single to the naked eye; yet when you point the telescope at them they burst into multiple components (sometimes as many as 4)! These are termed optical binaries. Among the famous ones are Mizar, Albireo, Rigel and Sirius. On this particular night, we ‘split’ the following stars successfully with the 100ED:
Castor
Mizar
The Winter Albireo (145 CMa)
Cor Caroli
All of these were brilliant sights as always.
Then the scope was pointed towards the globular cluster Messier 3. What are globular clusters (or globs, for short)? Ever seen a pins-box? Kind of like this one:
Now imagine that all those close lying pins are stars… and you have a Glob! To be more precise, it is an extremely concentrated (mostly) spherical arrangement of stars. It really looks like this
Beautiful, isn’t it?
Finally, we trained the 100ED on Saturn and observed it for a while with the zoom at around 150x. But you haven’t really seen something, unless you have seen it up close! So I decided to put in the highest power eyepiece that was available to us, the 4mm Plossl (along with a Barlow lens attached; Yikes! This must surely be one of the worst practices any astronomer could possibly do)
But the views just blew us away. The surface detail seen was unprecedented through the 100ED! One could have fooled it for Jupiter had the rings not been there. Hints of the recent Dragon Storm could be detected. And as many as 4 moons of Saturn were visible. The Cassini Division, while not obvious, was peeked at when seeing steadied. The view was just about equivalent to this (simulation view Stellarium)
Overall, it was just an exhilarating experience.
Finally it was getting quite late, so the scope was packed and brought back home. And thus ended the last of this weekend’s astronomy night.
Written By: Ramiz Qureshi