Week 1 (24 Sept): Assignment 2


(A) On a notecard or similar unlined piece of paper draw a circle by tracing the outline of a quarter. Take your notecard and a pencil outside and look closely at the Moon with your unaided eyes (or glasses if you are like me). Do you see that it is not all the same brightness? Draw what you see, being careful to position the light and dark stuff in about the right positions and having the correct sizes and shapes. Write down any impressions you have, the time of observation and where the Moon is in the sky. And be thankful you don't live in North Dakota and that this course isn't starting in February.

(B) Only after you've done part (A), print out the labelled photograph and compare it with your drawing. Can you recognize the main features?
Here are the features that you should learn to identify, because we will refer to them during the course:

Mare Imbrium, Mare Serenitatis, Mare Tranquillitatis, Mare Crisium, Mare Nectaris, Mare Humorum, Oceanus Procellarum.
These are all dark features (at full Moon) and are huge plains of lava flows, erupted about 3.5 billion years ago.

Plato, Archimedes, Copernicus, Alphonsus and Tycho.
These are all large and conspicuous impact craters. When seen near full Moon, Copernicus and Tycho are the centers of long streamers of bright ejecta called rays.

You can add your part (A) drawing to your wiki page by scanning it or taking a photo with a digital camera and then uploading it to the wiki. All of the maria in part (B) are visible this week to your unaided eye; with binoculars you can see most of the craters. Take a look.



My Sketch:

thEMW_sketch20070924.jpg

This sketch was made on Monday 24 Sept. We were at the Observatory (I teach Monday nights) and I had my students also make sketches. It shows the tree line off to the ESE, the outline of an ivy covered light pole and the moon roughly to scale with how I saw it on the horizon. Above that is a bigger drawing of the moon showing the maria. I have a hard time seeing the man in the moon, but the upside down bunny on the west edge (right) has always... well, jumped out at me! The moon was so close to full that it was really hard to draw the unlit sliver so it's actually quite a bit bigger than it should be.

So although I also had my students view through the telescopes and make sketches, I didn't make one myself that night (too busy with overseeing one class as well as interns)...

But Tuesday night, working again with the interns, we looked again at the moon and I made a very, very quick and messy sketch. This was done "freehand" meaning that I didn't look at the paper while I sketched... I just looked in the eyepiece and ... so the circle of the moon is not exactly complete (because of the angle of the pen) and some features seem to overlap...

[Hang on... I need to label it in Photoshop]

My freehand sketch:

thEMW_sketch20070925.gif I know it's messy!

Okay, so, I was observing through a ~7" refractor, so the view was upside down (but between the diagonal, the way I was lined up with the scope/eyepiece... yeah, the moon was not exactly oriented like the map!)... with a 40 mm eyepiece and a variable polarizer. And then trying to interpret what I had drawn... it didn't make sense until i remembered that the moon was probably upside down and then the features fell into place.

Okay... a photo next...


Here's a photo taken on Monday evening...
Canon 20Da primefocus through an 8" Celestron Ultima
The field of view of the camera is just smaller than the telescopes, so I couldn't fit all of the moon in. So I concentrated on the side with the terminator (top edge).
EMW_20070924.jpg
Craters are labeled in red and the maria in blue.

I took another picture on Tuesday night, this time holding my camera (sans lens) up to the 7" refractor (effectively a primefocus shot but I didn't have all of the connectors...)... and this view is rotated from yesterday's image, the terminator is now more on the left side...
EMW_20070925.gif
The shot was a bit overexposed, but when I played with it in Photoshop and balanced out the levels, I really liked how the colors of the maria (look at Imbrium and Serenitatis) stand out. So in the animation, one frame is the image as it appeared straight out of the camera and the other is the processed image, all with the features labeled.
- adastragrl adastragrl Sep 26, 2007