by canopia » Thu Nov 08, 2018 7:12 pm
Mars really is closer to the Earth in the middle of the loop, so it is looking the brightest. In fact, this past Mars season was a very favourable one for planet observers, with the red planet coming to a perihelic opposition on 27th July and shining at mag. -2.8, its brightest since 2003.
To better record the changing brightness of Mars, I used a diffusion filter in roughly 3/5 of the total exposure time of each picture, which were recorded by a digital SLR and a 50 mm lens. In late April, Mars was shining at -0.1; it got brighter until the opposition with the Earth catching up with Mars. Then it got fainter obviously, as the Earth started to pull away. The last image of Mars from November has the red planet shining at -0.5.
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JohnD wrote: ↑Thu Nov 08, 2018 6:47 pm
It's strange that in that pic, the images of Mars IN the loop appear significantly bigger and brighter than either side, which reinforces the illusion that it is looping to nearer the observer.
Obviously an illusion, but why? Apparent slower motion in the loop?
Mars really is closer to the Earth in the middle of the loop, so it is looking the brightest. In fact, this past Mars season was a very favourable one for planet observers, with the red planet coming to a perihelic opposition on 27th July and shining at mag. -2.8, its brightest since 2003.
To better record the changing brightness of Mars, I used a diffusion filter in roughly 3/5 of the total exposure time of each picture, which were recorded by a digital SLR and a 50 mm lens. In late April, Mars was shining at -0.1; it got brighter until the opposition with the Earth catching up with Mars. Then it got fainter obviously, as the Earth started to pull away. The last image of Mars from November has the red planet shining at -0.5.
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[quote=JohnD post_id=287153 time=1541702834 user_id=100329]
It's strange that in that pic, the images of Mars IN the loop appear significantly bigger and brighter than either side, which reinforces the illusion that it is looping to nearer the observer.
Obviously an illusion, but why? Apparent slower motion in the loop?
[/quote]