Sharing astrononomy information, references, pictures and tools
Our Moon 1st Quarter
Highlights Of Our Moon Near The 1st Quarter
This page offers some of my favorite Moon features that are best observed when the moon is in it's 1st quarter and only half lite a week after the new moon.
Download the 'Virtual Moon Atlas' or find one of the many other references on the web.
Below is a crude finder chart followed by a brief discussion of the features seen best at 1st quarter.
Many may feel the best time to observe the moon is when it is full. This is a fun thing but to see the features of the moon best you want to observe the moon when shadows highlight the features.
Some Of The Highlights. A few of these will have pictures below the text
* Plato Crater is on the top edge of vast Mare Imbrium. Large scope can see a split for a section on left
* Clavius Crater has many little craters within to test your scope's resolution limits. In the far south
* Rupes Recta (The Straight Wall) at 1st quarter is a long dark shadow case by a steep dropoff in elevation. When the sun is on the other side this line is more of a white line when the sun is on that side A much more difficults feature is a far less distinct ridge seen in the left of this picture.
* Alpine Valley is near the top to the right of the famous Plato crater. It is a long flat valley right to left
* Tycho Crater has large mount in the middle and stepped walls. A picture of Tycho is below but it could be argued that seing this in full moon shot shows vivid ejecta pattern radiating away across the moon.
* Cassini Crater has 3 small craters, 2 within it. Cassini also has interesting ripples on it's floor.
* Montes Apenninus and other mountains form a striking ridge that at this time of the moon cycle casts shadows across the lunar surface. These mountains are HUGE!
* Rima Hadley is the site of the Apollo 15 landing. You cannot see the lander but there is a long ditch or Rima that shows as a thin dark curving line. This is a more difficult thing to see, larger scope is best.
* Lunar X - This you must catch right as the light to dark 'terminator' is crossing it. It is a lite up 'X' that is because peaks are lite up so you see an 'X'. This is just before 1st Quarter.
Rupes Recta (Straight Wall)
Rima Hadley & Apoll0 15 Site