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The Mars Year - 2003
Mars Day on TV - KTVT CBS Channel 11, Dallas
Welcome to Wired News
Wired News: Spending Green to See Red Planet
Annular Eclipse - May 31, 2003
Lunar Eclipse - May 15, 2003
Transit of Mercury - May 7, 2003
Mid-America Astrophysics Conference

The Mars Year - 2003
Mars Day on TV - KTVT CBS Channel 11, Dallas
Welcome to Wired News
Wired News: Spending Green to See Red Planet
Annular Eclipse - May 31, 2003
Lunar Eclipse - May 15, 2003
Transit of Mercury - May 7, 2003
Mid-America Astrophysics Conference

What is an

On August 27, Mars will make its closest approach to earth. On that date, it will subtend an angle of 25.1 arc-seconds, thus making surface features visible in most backyard telescopes.

Arc-seconds is an measure of angle against the sky. There are 360 degrees in a circle. In each degree of a circle, we measure 60 minutes of angle, called an arc minute. There are also 60 seconds in a minute. Thus,  an arc second is 1/60 of an arc minute, or 1/60 of 1/60 of a degree. Very narrow.

A measurement in arc-seconds gives an idea of how wide an object will appear in the eyepiece of a telescope.

For example, the moon subtends a diameter of approximately one half degree in the sky, which is about 30 arc minutes. That is about 1,800 arc-seconds. At 25.1 arc-seconds in diameter, Mars is still relatively tiny, but still much larger than usual, not much smaller than the size of Jupiter in the eyepiece.

 NASA Photo Mars 2001.

Opposition Timetable

In January, Mars is not far to the right of Venus in the first few weeks of 2003. The rival of Mars in color, Antares is brighter than Mars this month.

In February, Mars and Venus are still together in the dawn sky, but continue to separate. At month's end, they are well to either side of the Teapot in Sagittarius.

In March, Mars rises several hours before dawn and makes a fascinating passage through the deep sky wonders of Sagittarius.

In April, Mars rises several hours before dawn and is fairly high in the south-southeast as morning twilight glows. It is still only 8" to 9" wide in telescopes, hardly large enough to show any surface details.

In May, Mars still rises well after midnight, but it is now the brightest object in the sky, a negative-magnitude orange fire. A telescope reveals Mars growing to more than 10" across. It is now possible to see a few details on steady nights. Spring begins in the southern hemisphere of Mars on May 5, so we should already be able to see the polar ice-cap.

In June, Mars finally starts to rise as early as midnight, and has brightened to a spectacular magnitude -1.5. The disk now swells from 12" to 16". By now, grey or seemingly green surface markings should be visible in medium-sized telescopes.

In July, Mars doubles in brightness, its orange flame now burning at -2.3. Mars begins retrograde motion relative to the stars July 29-30. The relative size of the planet is now 16" to 22"—the biggest it has appeared since 1988. The southern half of Mars is becoming ever more tilted toward Earth and the rapidly melting polar ice-cap is a fascinating sight. On the morning of July 17, viewers in North America can see Mars perched on the upper edge of the Moon; there will be a spectacular occultation of Mars for viewers in the extreme southeastern US.

In August, Mars, located in the constellation Aquarius, makes its closest approach to Earth on August 27, with an apparent diameter of 25.1" and a magnitude of -2.9. The planet reaches perihelion on August 30, only two days after opposition. Observers should see intricate details on the Martian surface, unless they are obscured by dust storms, but the southern polar ice-cap will now be a tiny speck as the Martian summer approaches. For observers in northern latitudes, Mars will be only 34 degrees above the southern horizon. If you have a fairly large telescope, try to catch a glimpse of the Martian moons, Phobos and Deimos.

In September, Mars still holds center stage at magnitude -2.9 and diameter 25". Earth now begins to pull rapidly away from the planet and Mars will begin to lose brightness. By month's end, magnitude will have decreased to -2.2 and diameter to 22". But Mars now reaches its highest point before midnight, making it convenient for observations, with a higher likelihood of steady skies.

In October, Mars is still a stunning sight, although it will fade from -2.2 to the brightness of Sirius by month's end. The diameter of the planet will also shrink from 22" to 15". Mars now does not set until well after midnight.

In November, Mars remains a bright object, but its diameter has dwindled from 15" to 11". It is still big enough to show some interesting surface markings on steady nights.

In December, Mars is still the most prominent object in the sky, shining at about 0 magnitude. Unfortunately, the planet is only 40% as wide as it was in August and shows few surface markings in medium-sized telescopes.

AAAA Mars Card

The AAAA Mars Card is a concise way to learn the essential information about Mars during the current favorable opposition in August and September 2003. Just click on either image to down load our PDF, print it off, and make copies for yourself and to hand out at your own Mars Observing Events for friends and the general public!
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Planning for the Public

In planning any special Mars observing activities for the general public or the media, keep in mind that in late August when Mars is closest (diameter about 25 arc sec), it will only rise about 30 degrees above the horizon at midnight ... so not good for "early evening" observing. However, this situation improves through September: at end of September, Mars will still be over 20 arc sec. in diameter, but will cross the meridian (a bit more than 30 degrees high) earlier ... about 9:30PM. This placement is somewhat better for public programs.

As always, there is the danger of planet-wide dust storms at this perihelion. Storm activity on Mars will easily wipe out any surface features otherwise visible.

The Planetary Society has proclaimed August 27, 2003, the date of opposition, as "Mars Day". The Planetary Society has a goal of "half of the world's population looking at, or thinking about, Mars" on Mars day. So please circle this day on your calendar. Now is the time to start planning Mars Parties in your local area.

Oppositions of Mars 1988-2003

This chart by C.F. Chapin shows the relative positions of Mars and Earth for the years 1988 to 2003. The last great opposition of Mars was 1988. On August 28, 2003, Mars will be at its closest approach to Earth in recorded history, at a distance of only 34,646,418 miles.

Click on image for enlarged view

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