Venus and Mars have been putting on a fine show in the western sky after sunset. Last night the moon joined the planetary duo in, from the photos I've seen, a beautiful gathering. Alas, it was cloudy here in Tucson.
Tonight the moon had moved on but Venus and Mars were super close, just 0.4 of a degree apart in the sky. Alas, we had clouds again, but not quite enough to completely foil the view.
The Moon made its appearance first, largely hidden by the veil of the clouds.
Tonight the moon had moved on but Venus and Mars were super close, just 0.4 of a degree apart in the sky. Alas, we had clouds again, but not quite enough to completely foil the view.
The Moon made its appearance first, largely hidden by the veil of the clouds. 
Occasionally, the clouds parted enough to let me almost get a clear shot at the moon.
For most of the evening Venus and Mars were completely obscured by the clouds, but as they got lower in the sky, they dropped below the cloud deck and popped into view. That's Venus on the left and much fainter Mars to the right. Venus is almost 100 times brighter than Mars.
Why so bright? Three reasons - Venus is closer, larger and more reflective (it's surrounded by white clouds).
You might wonder how and inner planet (Venus) and an outer planet (Mars)
could be so close together in the sky. At first thought it feels like
one should look in different directions to see them, but that obviously wasn't the case tonight.
A screen grab (above) from the SkySafari app shows how this can be (I added the red line). Looking inward from Earth you can tell that, even though Mars is an outer planet, it is in essentially the same direction as Venus. Earth, Venus and Mars make a straight line. So, when we look from Earth, we see Venus and Mars close together. As the nights move on, they'll gradually move apart in the sky, with Mars gradually sinking lower into the west each night until it is eventually lost from view.
No comments:
Post a Comment