Feature Article
August 7, 2003
LAND O' LAKES NewsWeb HomeContact Us
An Appearance of Mars That is Truly AmazingIn the month of August, we always expect to enjoy longer nights than we had in July, and therefore, we have more time to enjoy the nighttime views along the Summer Milky Way as it sweeps overhead from the northeast to the south in the late evenings. As we gaze up, from a rural setting, at the immense swirls of stars that populate the Milky Way, we need to remind ourselves that this great band of light is one arm of our enormous home galaxy, the Milky Way Galaxy, which is composed of over 200 billion stars, with our sun and its planets being just one system within its vast expanse.
Among the five bright planets that can often be seen with the unaided eye, only three of them are putting in an appearance this month, and two of those are not in prominent positions, as if four of the bright planets are taking a rest this month so that one planet alone can dominate the night sky and be the deserved centre of attention for everyone on earth. Venus and Jupiter, which are normally the two brightest planets of all, are unseen this month, since both of them are on the far side of the sun, at the positions in their orbits known as in conjunction with the sun. For the first few days of the month, Mercury may be seen for a short while low in the western sky beginning about 45 minutes after sunset, but those who do not have a good view of the western horizon are bound to miss it entirely. Saturn may be seen among the stars of Gemini, rising in the east at about 3:00 a.m. and climbing higher in that part of the sky until the onset of morning twilight . Of the five planets, that leaves only Mars, and what an incredible month it is for the Red Planet, the one that we once thought had living intelligent creatures, the one that we still think might once have had running water and may still have frozen water beneath its reddish, sandy soil.
Many people have noticed that Mars has brightened considerably over the past two months. It may, in fact, now appear brighter than anyone can recall seeing it ever before. This month there is absolutely no mistaking it for anything else in the sky, because of its brilliant reddish glow, and during August it will just get brighter and brighter. Try, not just to see it, but to note its apparent slight movement from night to night among the background stars of the constellation Aquarius. If possible, make a sketch of the planet and the nearby stars in order to be able to appreciate the planets movement during the month. In early August, it can be spotted in the east at about 10:00 p.m., but it rises earlier each evening until, by the end of the month, it rises at about the time of sunset. It completely dominates the southeastern and southern sky for the remainder of the night until morning twilight. That is because we are approaching, in late August, what astronomers call a close opposition of Mars, and this one is an amazingly close one!! Those who have followed the planets may recall that there have been alternate years (1997, 1999, 2001, and now 2003) when Mars has been bright and easily seen and large (when seen in a telescope), but during the intervening years it was either small (in a telescope) and faint, or else not seen at all. In fact, as viewed from the planet Earth, Mars seems to be on a 26-month cycle, because every 26 months Mars is easily seen to be fairly close to Earth. That is when the event that astronomers call Martian Opposition occurs. This means that Sun, Earth, and Mars are in a straight line with the two planets on the same side of the Sun. Occasionally, when that event occurs in the summer time (since it is in early July that the Earth is at aphelion (the farthest point in its elliptical orbit from the Sun) AND if Mars happens to be near the perihelion point in its orbit (the point in its orbit when it is closest to the Sun), then there is an even closer than usual Mars opposition. Also, there are other factors, such as nearness of other planets, that astronomy experts can use in fine-tuned calculations to predict when certain oppositions are even closer than the unusually close ones. After much time spent in such calculations, these experts not tell us that what happens in the last week of August this year is a truly rare event. On August 27, Mars will be only 57,758,006 kilometres from Earth, closer than it has been at any time since the year 57,617 B.C., over 59,000 years ago!! Of course, over those 59 thousand years, there have been many times, such as in 1924, when Mars has been quite close, but never really and exactly this close!! The next time that Mars will be this close, or closer, will be on August 28, 2287!! So, be sure to enjoy the view of Mars this time. You will not likely ever see it any closer to us than it is this month.
Those astronomers, who have good telescopes to try to see details on the surface of Mars this month, have mixed expectations, especially when they think back to what happened 26 months ago. Since Mars is considerably smaller than the planet Earth, our view of its surface details is not as good as their imaginary astronomers would have of the details on our planet; therefore we have to take advantage of the time near Martian oppositions to study the landscape. The problem is that at certain times when Mars is fairly near its perihelion (the exact date of which is August 30) there have been huge sandstorms that obliterated many features on the surface. That is what happened in the year 2001. Many Mars observers were quite disappointed because of those 2001 Martian sandstorms. Early indications from some of the summer of 2003 observers, beginning a couple of weeks ago, were that similar sandstorms had started on some areas of the planet. We can only hope that such storms, which may be caused by a slight rise in the Martian temperature, will not spread to the whole planet and thereby obliterate even our views of the polar ice caps!
This month we will be easily able to see the moon move past two of the planets. On the evening of August 12, in the southeastern sky, the moon will be just to the right of Mars. The following evening, August 13, the moon will have moved past the Red Planet, and appear to its left, providing a fine lesson in the apparent distance that the moon travels across the sky in one day. Try not to miss the view those sights. Try also to rise very early on the morning of August 23 in order not to miss the sight of the crescent moon hanging in the eastern sky beside the planet Saturn.
The Perseid Meteor Shower is always an August event anticipated by skywatchers. This year, unfortunately, the dates of the peak, August 12, 13, and 14 are times when the Full Moon will interfere with seeing many of these shooting stars; however this long duration shower lasts for weeks, and I have, in fact, seen some already. Watch for them throughout August. This is often a good month for observing these and many other meteors. For more information about observing meteors and other objects of the night sky, a recommended book, The Beginners Observing Guide, is now available at Sharbot Lake Pharmacy.
