On Tuesday, July 12, 2011, the planet Neptune will complete its first revolution around the sun since its discovery on September 23, 1846. As it takes Neptune 164.79 Earth-years to go full circle through the constellations of the Zodiac, it is only now completing its first full orbit since its detection by humans. Hence the anniversary celebration.
Neptune, the 8th planet outward from the sun, is presently the most distant planet in the solar system. That’s because the International Astronomical Union reclassified Pluto as a “dwarf planet” in 2006. By the way, Neptune circles the sun three times for every two times that Pluto does.
There is much to commemorate — Neptune’s discovery marked a turning point in astronomy. Its existence was revealed, not through a serendipitous observation by an astronomer but by the careful work of mathematicians. They calculated that perturbations in the orbit of Uranus, then thought to be the sun’s most distant planet, could only be explained by the existence of another, even remoter world whose gravity was affecting Uranus’s path.
The mathematicians – Englishman John Adams and Frenchman Urbain Le Verrier – made their calculations separately. Both agreed, however, where in the sky astronomers would pinpoint the planet causing those perturbations. But they dealt with the information very differently, says historian Allan Chapman of Wadham College, Oxford.
As Neptune is too faint to be seen by the naked eye, a pair of binoculars or a telescope is needed to view this world if you know where to look. This detailed sky chart will help you to find Neptune’s place in the sky — it will be located in Aquarius, the constellation where astronomers discovered the blue planet.
Next month Neptune reaches opposition and is a decent target for observers.
Happy Birthday, Neptune! 🙂
Here is another rare planetary grouping that is hard to miss! 🙂
As soon as I came across this website shared by Daniel Fischer and read about the proximity of Venus and Jupiter to each other on May 2011, I immediately ran my Stellarium software and simulated planetary positions throughout that month.
I got excited when I saw the nice planetary grouping of Jupiter, Venus, Mars and Mercury (you can add Uranus and Neptune to your count if you have binoculars or a small telescope) with the thin waning crescent Moon during the predawn hours of May 1 and 2.
All of these celestial objects will lie just within the constellation Pisces, separated by only a few degrees from each other. 😀 This is a good opportunity to spot all these planets close together during one occasion.
In order to observe this, you must have a clear eastern horizon because they will appear very low in the sky. Also, be sure to bring a pair of binoculars to help you see these objects better and wake up early to avoid the glare of the sun.
Venus is, as always, the brightest and most visible of the planets, and it can be your guide to spotting the others. About half way between Venus and the rising sun is Jupiter, the second brightest planet.
Mars will be a tiny speck just above Jupiter, and Mercury another tiny speck about half way between Jupiter and Venus. Uranus is slightly more than one binocular field above and to the right of Venus, and Neptune is much farther to the right, about 40 degrees away in Aquarius.
The planetary grouping is visible from April 23 to May 30.
Astrologers have always been fascinated by planetary alignments, and the doomsayers of 2012 have been prophesying a mystical alignment on Dec. 21, 2012. They view planetary alignments as foretellers of disasters. Modern amateur astronomers look forward to them as nothing more than grand photo ops. In fact, the modern tools of astronomers, such as planetarium softwares, show otherwise: absolutely no alignment at any time in 2012.
Happy observing 😀
For Philippine sky gazers, the planets Venus and Neptune will make their greatest appearance for this year on the evening of August 20 😀
The brightest planet in the solar system, Venus will appear especially prominent because it will climb to its highest point in the evening sky upon reaching its greatest elongation. It will lie 47° from the Sun, its maximum distance for this appearance.
Also on this night, the planet Mars will lie just 2° above Venus. (That’s approximately the width of one finger when held at arm’s length.) Using binoculars will help bring it to view because it glows less than 1 percent as Venus. The planet Saturn lurks approximately 10° to Venus’ right and the star Spica in the constellation Virgo sits 10° to Venus’ left. Both shine a little brighter than Mars but fall far short of dazzling Venus.
Although naked eyes and binoculars offer the best views of the evening scene, anyone with a small telescope will get a thrill from targeting Venus. At greatest elongation, Venus looks like a miniature version of a First Quarter Moon, with one half in sunlight and the other in darkness.
On the other hand, the planet Neptune will be in opposition (opposite the sun in the sky and closest to Earth) and will be highest in the sky at local midnight. This opposition is special because Neptune will be returning close to the spot where it was discovered in 1846, marking its first complete trip around the sun since its discovery.
To find Neptune, look for the large but faint triangle of Capricornus, to the left of Sagittarius and the Milky Way around 1 a.m. this week. The two stars at the left end of the triangle point the way to Neptune, just a little bit short of and above the star Iota in the neighboring constellation Aquarius.
In a small telescope or even binoculars, Neptune will look just like a star; what gives it away is its distinctive blue-green color.
Happy planet hopping! 😀