Examining the Phases of Venus

rod

Oct 22, 2019
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Very good report. Last year from November 2018 through January 2019, I viewed Venus using my 90-mm refractor from 31x to 180x observations and tracked the planet's retrograde loop and position changes from Virgo through Ophiuchus. Venus in the telescope view shows dramatic changes in brightness, arcsecond size and area illuminated, and at times some cloud banding visible too. Venus in November 2018 was near 53 arcsecond angular size, by the end of January 2019, 19 arcsecond angular size. All of this is very noticeable in a small, quality telescope view demonstrating how quickly distance changes take place between Earth and Venus as well as the angle on Earth you are viewing Venus from. You can watch the heliocentric solar system in motion :)
 
Oct 26, 2019
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I'm new to the astronomy. I have a 5 inch Newtonian telescope. I was looking at Venus last night. It looks like a bright spot in my eye piece. I would like to see some details. Detail like, "at times some cloud banding visible." How do I see that?
 
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rod

Oct 22, 2019
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I'm new to the astronomy. I have a 5 inch Newtonian telescope. I was looking at Venus last night. It looks like a bright spot in my eye piece. I would like to see some details. Detail like, "at times some cloud banding visible." How do I see that?
Rjartist, I find viewing Venus using a planetary filter helps. I frequently use a #38A Blue filter and sometimes a Moon filter too :) Venus can be bright and this reduces glare. I use a 90-mm refractor viewing Venus and can see some cloud bands at 80x to 200x. Venus is currently about 13" angular size so you will need some power and filter(s). My log shows cloud bands distinct in places when Venus some 28" or more in size. Back in Dec-18, I logged "Very good views and some cloud bands distinct near terminator line and equator region near terminator line. Venus close to First Quarter Moon shape now. Venus 44.76% illuminated, 28" size." I was viewing at 78x or more. Use a good planetary ephemeris too for Venus magnitude, illuminated area, angular size, etc. Software like Starry Night, Sky Safari, Stellarium provides this as well as magazines like Astronomy or Sky & Telescope. Keep in mind, Venus generally does not show much detail like observing Mars at opposition, Jupiter, or Saturn.
 
Apr 25, 2020
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I observed Venus last night and it had a "bite" out of it (as if it was being exclipsed), which diminished as it became later. How can that be? (Culver City, CA, looking east around 9PM). Photo after the "bite" on the bottom had diminished quite a bit:
 

rod

Oct 22, 2019
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I do not know. This year since 01-Jan-2020 through 20-April-2020, I viewed Venus 15x using my 90-mm refractor telescope and Newtonian 10-inch reflector. Venus never looks like your image in my eyepieces. At the beginning of this year Venus was near 13" angular size and now is more than 33" angular size, less area illuminated too. By the end of this month Venus will be 38" size and 26% illuminated area. Your image looks like the object is nearly 100% illuminated, minus the "bite". Venus ephemeris in Sky & Telescope monthly magazine, Starry Night, SkySafari, Stellarium software, will show the phase, size, and illumination of Venus when viewing as well as the planet's distance. My observations of Venus this year range from 31x to 200x views and with different filters too, sometimes cloud banding is slightly visible in the telescope view. This year Venus had close conjunctions with Neptune and Uranus, also M45 star cluster. Very enjoyable views of Venus passing near and through M45 star cluster as well as close to Uranus and Neptune.
 

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