| Old Town Astronomers Home | White Oaks Home | Jane Houston Jones Blog
Mars August 2010
Mars will not appear larger than the moon - more like this, but smaller ------>
Updated August 27, 2010
Bookmark this page for Mars in August 2011 info!

See bright Venus, faint Mars and Saturn, western horizon, August 27, 2010

Here's a closeup of the three planets tonight

Use these star charts to locate Mars tonight, August 27th. On August 12, we saw the trio of planets low in the western sky just at sunset. Tonight, you'll have to wait until about 10 p.m. to see the moon rise in the east. That bright object near the moon is not Mars. It's Jupiter! The moon and Mars images in the upper right of this page were taken on the same night, using the same camera and same telescope in 2005. Thanks to CA amateur astronomer and astrophotographer Paul Keen for making the side by side comparison. If he were to make the same image comparison tonight, Mars would be a much smaller object because it's more than twice as far from Earth this year! Watch my August What's Up Video to see what's up in the sky this month besides Mars.:-)

2010 marks the eighth annual return of 2003's Mars In August email. It says something about Mars appearing as large as the moon, but there are annual variations to the theme - one year a ridiculous Powerpoint mis-information file was attached to the email. Sometimes the email mentions a particular date (like August 27th) when the moon and Mars will appear as two big moons. That date refers to when Mars was closest to Earth in 2003, and it did look quite large through a telescope back then. But even then, Mars was 36 million miles away from Earth, while the moon was about 250 thousand miles away. So it is just impossible for Mars to ever appear the same size as the moon!

The original email compared a telescopic view of Mars to a naked eye view of the moon. It never said Mars and the moon would appear to look the same size with the unaided eye. But every rewrite of the 2003 email omitted that telescope view comparison info. :-(

The email does give us a great opportunity to test our critical thinking skills. Critical thinking is a way to apply the scientific method to everyday life, and everyday life includes getting weird claims delivered to your own e-mail in-box. Here's what you can do:

Your Mars Resource Guide, updated for 2010

Mars is the only planet with a surface that can be easily seen through amateur telescopes. Despite its small size, which is about half the size of Earth, Mars has higher mountains, larger rift valleys, and larger impact basins than Earth. Most of these intriguing geologic features are covered with dust, which obscures the view from amateur telescopes. What we mostly see through telescopes is darker cratered terrain in the south and lighter smooth plains in the north. The north polar cap is also easy to see right now, too!

What will Mars look like in your telescope? It depends. You may be able to see different color markings on the planet clearly, depending on such variables as the quality and cleanliness of your telescope optics, magnification and quality of your eyepieces. Weather and atmospheric conditions, both on Earth and Mars impact your view too. If you are observing Mars at low power through a small 60mm - 100mm aperture telescope, Mars will look like a small orange disk or sphere, and you may see some dark markings and the north polar cap (at least now through February 2010). Larger telescopes will reveal not only details on the planet, but also some haze on the limbs or edges of the sphere.

Here is an image showing the apparent size of the moon and Mars imaged when Mars was a little larger than it is now. Image compiled by Gary Spiers, used with permission. During closest approach in 2010, the apparent diameter of Mars was 14 arcseconds (arc sec) or a little less than half the apparant diameter of Jupiter which is easily visible and very bright in the southern sky from late evening until dawn. Jupiter is 34 arc sec in diameter. Compare the two objects if you can.

January 2010 - Mars at Opposition: The diameter of Mars this year was a little smaller than it was last opposition in December 2007. It was at opposition on January 29th, and reached its closest approach to Earth a few days earlier. Mars was 69 million miles from Earth at opposition in January. Mars won't be this big or bright again until 2014. Remember how the moon and Mars look side-by side this month. Then, in August, when that dopey Mars Hoax email comes back to haunt us, you can tell everyone you saw Mars in January 2010 when it was closest to Earth and it was definitely not as big as the moon. :-)

February 2010: Mars was visible all night long. Did you see any changes in the North Polar Cap? Mars got smaller as the distance between Earth and Mars grew. Februay was "Get out and have a look at Mars if you haven't already" month. You will be sorry if you missed it!!

March 2010: Mars shrank in size as Earth overtook it in the sky. This is the final month of really good Mars views this year.

April 2010: If you looked at Mars in the southern sky during April, you saw it has a gibbous or shrinking phase. But from the 15th to the 18th Mars passed near the pretty open cluster, M44, which is also known as the Beehive cluster. Mars set by 2:30 am eastern time in April.

May 2010: You could find Mars in Leo in may in the south-western sky, smaller than in April. It is now half the diameter it was in February. Did you see the shadow edge making Mars gibbous phased? Mars was now at summer solstice and the North polar cap should have melted away.

June 2010: Mars was now just a small dot and featureless in most telescopes. But it was near a fantastic star, the heart of Leo -- Regulus this month -- from June 3-9.

July 2010: Watch Mars, Saturn and Venus draw together in the Western sky at sunset. Mars was less than three degrees from Saturn -- about half of your closed fist held towards the sky.

August 2010: Mars and Saturn make a dramatic trio with brighter Venus on August 12th. Skywatchers will enjoy seeing of the three planets closely gathered on August 8th. On the 12th and 13th look for the slender crescent moon near the trio of planets. Venus is the brightest, Saturn is the next brightest, and Mars is smaller and fainter.Mars is 185 million miles from Earth this month.

September-December 2010: Mars is 200 million miles from Earth in September, and becomes lost in the sunset for the rest of the year. My own monthly NASA podcast What's Up Podcast offers up some great viewing tips each month. The January 2010 podcast was about January's Mars Opposition, and shows you when and where to look if you want to see the side of Mars where Spirit, Opportunity and Phoenix are located.

Here's a good link for celestial highlights for the current week (and every week). This Hubble image depicts Mars in its orbit around the sun, showing the apparent relative size of the red planet at opposition for the last several oppositions. 2010's closest distance between Earth and Mars will be 62 million miles in January 2010. Look at the 1995 and 1997 images to get an idea what the apparent size of the planet will be then.

Here are some good Mars links.

Sketches and images of Mars 2001-2007

Missions to Mars

| Old Town Astronomers Home | White Oaks Home | 2007 sketches | 2005 sketches || 2003 sketches |
created by Jane Houston Jones
Index last updated: