APOD 4.1

For this week's APOD, I chose the picture called MESSENGER at Mercury.  It is an image taken on March 17 by the MESSENGER Spacecraft.  The picture shows some of Mercury's many craters and terrains.


The MESSENGER Spacecraft was the first spacecraft to go into orbit around Mercury, which is the innermost planet in our solar system.  Although Mercury will offer good views this month due to this planet wandering away from the Sun in the Earth's sky, it is still better seen from spacecrafts in orbit around it.  The picture shown is the first image of the planet in color since the spacecraft entered the orbit.  In comparison to the Moon, Mercury is bigger, more dense, and has about twice the surface gravity.  But even with these differences, the two tend to look very similar when first examined.  The terrain areas in the photograph are almost a shade of light blue and brown.  Many craters are seen within these terrains as well.   Towards the top of the photo, one can point out long streaks of material hitting the surface.  In the center of the rays in the crater Debussy, which happens to be 80 kilometers in diameter. The rays contain impact ejecta and secondary craters.  The part of the Debussy shown here is only a portion of the whole thing. At the other bottom end of the image of Mercury, terrain is extended to it's south pole, with a region that has never before been captured from space.

Astronomy Night 3/26/11

Tonight, I attended Astronomy Night from 7-9:30 p.m. on the Pine View Service Road.  There was a clear sky and when I first got there, it was still very light out, so no stars could be seen.  But as it started getting later and darker, we could start seeing some 2nd magnitude stars.  The first star that appeared was Sirius, from the Canis Major Constellation.  Then, the three stars of Orion's Belt could be seen, and then Canopus, and then Procyon.   Then I could pick out Betelgeuse, Rigel, The Big Dipper, The Little Dipper, Gemini (with Castor and Pollux visible), Taurus (with Aldebaren visible), The Little Dipper, and Polaris.  It appeared that the stars started to slowly shift to the west throughout the course of the night.  At around 8:30 p.m. Saturn started to rise in the east.  Two telescopes were set up in which we could view Saturn, and we could see its rings through it.

Observation 3/19/11

Tonight, I went out and looked up at the sky from my driveway in Sarasota at about 9:45 p.m.  The sky was a shade of dark blue, and only a couple of stars were visible, but not enough to correctly point out major stars or constellations.  I saw the moon shining very brightly in the south east, but mostly eastern, portion of the sky.  It is in its full moon phase (100% of the way illuminated), and appeared lower and bigger than usual.  Tonight's large moon is caused by the close proximity to the earth.  It is the largest moon to appear in or about the next f20 years, and an event like this hasn't occurred since 1992.  The close proximity of our moon will not cause any danger to Earth, even though it is thought to since it appears 15% to 30% bigger than usual.

APOD 3.8

For this week's APOD, I chose the picture called Mercury and Jupiter At Sunset.  It is a picture of a beautiful, serene landscape occurring towards the end of a warm evening sunset.  Up above the land, both Mercury and Jupiter are seen shining brightly in the Earth's sky.  The photo was taken earlier this week from the island of Froson in Sweden, as the scene looks across Lake Storsjon, toward distant mountains and Hallen village.


This is a good viewing month for Mercury, as it is straying away from the Sun in the Earth's sky.  As spring draws near in the northern hemisphere, the ecliptic plane is going to make a steep angle with the western horizon, making it easier to be viewed. On the other hand, Jupiter is going to continue getting lower each night after sunset.  Even in this image, we see that Mercury is quite a ways above Jupiter in the orange-hue sunset.  Since Mercury is our solar system's inner-most planet now, even better pictures of the planet are able to be taken with the Messenger Spacecraft, which is currently orbiting the planet.  The Messenger Spacecraft went into orbit around Mercury on about March 17, 2011, after being through more than a dozen laps through the solar system for NASA.  This durable spacecraft will carry seven science instruments fortified against the blistering conditions by the Sun, and will become the first spacecraft to go into orbit around this planet.

Observation 3/9/11

Tonight I went out and looked up at the sky from my driveway in Sarasota at about 8:15 pm.  Once again I saw the moon in the western part of the sky, about 20 percent of the way illuminated.  It is still currently in its waxing crescent phase.  Also towards the west in the sky, I am pretty sure that I saw a couple stars from the Pleiades Constellation.

Observation 3/8/11

Tonight, I went outside to observe the sky from my driveway in Sarasota at about 8:00 pm.  The sky was very cloudy at this time and not quite dark enough yet, so I was not able to see more than a couple of stars. I did see the moon though, in the western portion of the sky.  It appeared to be in its waxing crescent phase, with about 15 percent of it being illuminated.

APOD 3.7

For this week's APOD, I chose the picture called Lunar Nearside.  It is a picture of the lunar nearside of the moon, updated on March 3, 2011.  It is compiled from 1,300 different images from the Lunar Reconnaissance Orbiter spacecraft's wide angle camera.  These LRO pictures were all recorded over a two week period last December. 


The lunar nearside exists because the Moon rotates on its axis and orbits the Earth at the same rate, which would be about once every 28 days.  The rotation always appears to keep one side, called the nearside, facing towards Earth.  The Moon has this synchronous rotation because of Earth's gravitational field, which raises solid-body ties on the Moon.  It is because of all this that this high resolution compilation image of the moon, lunar maria (which are dark and smooth, and are actually lava-flooded impact basins), and rugged highlands, are so well known to astronomers and sky gazers here on Earth.  For this image, one can slide the cursor from a computer over the picture, to see all of the mares and main craters labeled.