On July 6 we will be farthest from the Sun – at the aphelion point of Earth’s orbit. Yet, because the orbit is not far from circular, this means we are only about 2,540,000 km farther out than average, which is small compared with the 149,597,870-km average distance. There is more about this in the “Sun, Earth, and seasons” section of Astronomical Calendar 2023.
As we look inward toward the Sun, we see to its left (that is, in the evening sky) our inward neighbor planet Venus, and, beyond the Sun, our next outward neighbor planet, Mars.
See the end note about enlarging illustrations.
In this picture, Venus is exaggerated 150 times in size to show the crescent shape of the sunlit part of it that you can see in binoculars. On July 7 this crescent will stretch to its greatest illuminated extent (294 square seconds). On July 9 Venus will be brightest, at magnitude -4.47.
And, on July 10, there will be a glorious “trio”: Venus, Mars, and the star Regulus fitting into a circle of diameter 4.65°. Regulus, 21st in brightness of our night sky’s stars, appears about one magnitude brighter than Mars.
As this blog insists on saying in its automatic sign-off, it maintains its right to be about astronomy and anything under the sun. Including the personal: Happy birthday, Roland! And welcome to England, Dan!
__________
This weblog maintains its right to be about astronomy or anything under the sun.
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” or “Open image in new tab”, 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.
I think that Venus’s orbit is pretty much circular with little variable distance to the Sun,with Earth there’s a bit of variety of distance but by the time you get to Mars it’s significant.I have never read about Mercury’s orbit but I’m guessing pretty much circular?On a different note I saw my first Noctilucent Clouds of 2023 on the 2nd of July and a rather poor display.2023 however is significant, for me at least,as the year I have seen both of the rare Middle Atmosphere cloud types as I saw my first Nacreous Clouds ever in January 2023.
No, Mercury#s orbit is the farthest from circular for the major planets, eccentricity 0.206.