White and red

There is busy solar-system activity in the after-sunset sky

See the end note about enlarging illustrations.

The Lion looks down calmly from his cosmic distance (the blue-white star Regulus is 77 light years away).

On the evening side of Earth, we are looking back along our orbit.  The point marked “antapex of Earth’s way” is the direction from which we are flying.  For pictures like this I am choosing a projection that makes the horizon slightly convex, because this reminds us that we are on a spherical planet, just one of the globes hurtling around in space.

The Moon is 28° and Venus and Mars 29° from the Sun.  At the time and American location chosen for the picture, they are 9° above the horizon.  The Moon will pass closest to Venus and Mars at 12h and 13h by Universal (Greenwich) time, which is 4 or more hours earlier by North American clocks.

The Moon, new on July 10 at 1:17 UT, will be an hour less than 2 days old, exquisitely slender, you’ll be lucky to see it.

The trio, or close grouping of three bodies, will be tightest on Monday July 12, at 12 UT, when  Venus, Mars, and the center of the Moon will fit in a circle of diameter 3.6°.

The appulse, or apparent closest moment, of the two planets comes on Tuesday July 13 at 14 UT, when Venus will be only about half a degree north of Mars.

Venus is shining at magnitude -3.9, Mars at 1.8.  This means that the luminosity of Venus is about 190 times greater; that is, about 190 times more sunlight is being reflected to us from Venus than from Mars.  Venus is larger, whiter, and, at present, nearer; both are farther from us than the Sun, and Mars is in the outermost part of its eccentric orbit; on July 13 it will be at aphelion, the outermost point, 1.67 astronomical units (Sun-Earth distances) from the Sun.

This space view shows the planets’ paths in July.  In yellow are sightlines to them from Earth on July 11.  The viewpoint is 15° north of the ecliptic plane, and 5 astronomical units away from the Sun.  The dashed line shows longitude 0°, the vernal equinox direction.  The Sun is exaggerated 4 times in size, the four inner planets 300 times.

Postscript on concolors

A constellation of colors on a London street.

I mentioned that I once catalogued (for Manchester University library) a book by someone with “Concolor” in his name.  Later I remembered, a little less vaguely, that it was Concolorcorvo, which must mean something like “one-colored crow.”  This enabled me to find out that the person was Alonso Carrió de la Vandera, who wrote a book he pretended was by Calixto Bustamante Carlos, alias Concolorcorvo.

Carrió was a jokey character.  He was from Gijón in northern Spain, but spent years managing the mail service across the Viceroyalty of Peru, which in the 1700s embraced the southern half of South America.

In 1775 there was published in Gijón a book called El lazarillo de ciegos caminantes desde Buenos-Ayres hasta Lima, “The guidebook for blind walkers from Buenos Aires to Lima.”  It was a valuable collection of observations – social and natural and geographical – made along the routes between the Atlantic and the Pacific, through what later became Argentina, Uruguay, Paraguay, Bolivia, and Peru.  The book purported to be written by Bustamante Concolorcorvo “from the memories of old Don Alonso Carrió de la Vandera,” but investigators have proved that it was written by Carrió himself.

“Lazarillo” referred to Lazarillo de Tormes, the anonymous satirical novel of two centuries earlier, which started the picaresque genre of roguish adventure tales.  The title character, “little Lazaro,” started his career of mischief by being apprenticed to a cunning blind beggar.

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ILLUSTRATIONS in these posts are made with precision but have to be inserted in another format.  You may be able to enlarge them on your monitor.  One way: right-click, and choose “View image”, then enlarge.  Or choose “Copy image”, then put it on your desktop, then open it.  On an iPad or phone, use the finger gesture that enlarges (spreading with two fingers, or tapping and dragging with three fingers).  Other methods have been suggested, such as dragging the image to the desktop and opening it in other ways.

Sometimes I make improvements or corrections to a post after publishing  it.  If you click on the title, rather than on ‘Read more’, I think you are sure to see the latest version.

This weblog maintains its right to be about astronomy or anything under the sun.