APOD: The Phases of Venus (2024 Jan 08)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 5423
Joined: Fri Dec 04, 2009 3:27 am

APOD: The Phases of Venus (2024 Jan 08)

Post by APOD Robot » Mon Jan 08, 2024 5:06 am

Image The Phases of Venus

Explanation: Venus goes through phases. Just like our Moon, Venus can appear as a full circular disk, a thin crescent, or anything in between. Venus, frequently the brightest object in the post-sunset or pre-sunrise sky, appears so small, however, that it usually requires binoculars or a small telescope to clearly see its current phase. The featured time-lapse sequence was taken over the course of six months in 2015 from Surgères, Charente-Maritime, France, and shows not only how Venus changes phase, but changes angular size as well. When Venus is on the far side of the Sun from the Earth, it appears angularly smallest and nearest to full phase, while when Venus and Earth are on the same side of the Sun, Venus appears larger, but as a crescent. This month Venus rises before dawn in waxing gibbous phases.

<< Previous APOD This Day in APOD Next APOD >>

maryplouffe
Asternaut
Posts: 1
Joined: Mon Jan 08, 2024 8:36 am

Re: APOD: The Phases of Venus (2024 Jan 08)

Post by maryplouffe » Mon Jan 08, 2024 8:38 am

How long does it take for Venus to complete one orbit around the Sun?
smash karts
Last edited by maryplouffe on Tue Jan 09, 2024 1:09 am, edited 1 time in total.

User avatar
Ann
4725 Å
Posts: 13542
Joined: Sat May 29, 2010 5:33 am

Re: APOD: The Phases of Venus (2024 Jan 08)

Post by Ann » Mon Jan 08, 2024 9:19 am

maryplouffe wrote: Mon Jan 08, 2024 8:38 am How long does it take for Venus to complete one orbit around the Sun?
It takes 225 days.

You can learn more about Venus here.

Ann
Color Commentator

Christian G.
Science Officer
Posts: 172
Joined: Sat Apr 08, 2023 10:37 pm

Re: APOD: The Phases of Venus (2024 Jan 08)

Post by Christian G. » Mon Jan 08, 2024 1:01 pm

Fun fact: a day on Venus lasts longer than a year on Venus!

User avatar
Chris Peterson
Abominable Snowman
Posts: 18322
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: The Phases of Venus (2024 Jan 08)

Post by Chris Peterson » Mon Jan 08, 2024 2:36 pm

maryplouffe wrote: Mon Jan 08, 2024 8:38 am How long does it take for Venus to complete one orbit around the Sun?
As Ann notes, its (sidereal) orbital period is about 225 days. But perhaps more relevant to what we see (and what is illustrated in today's APOD) is the relationship between the orbits of Earth and Venus. That results in Venus having an apparent phase cycle of 584 days.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com

EricOsman

Re: APOD: The Phases of Venus (2024 Jan 08)

Post by EricOsman » Mon Jan 08, 2024 5:14 pm

A truly full phase of Venus would be nearly impossible to see from Earth. The view from Mercury would be spectacular, of course. Has anyone seen a photo of the full phase of Venus by any of the few space probes that have ventured that far sunward?

User avatar
Chris Peterson
Abominable Snowman
Posts: 18322
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: The Phases of Venus (2024 Jan 08)

Post by Chris Peterson » Mon Jan 08, 2024 5:31 pm

EricOsman wrote: Mon Jan 08, 2024 5:14 pm A truly full phase of Venus would be nearly impossible to see from Earth.
You could say the same thing about viewing the phases of the Moon from Earth!
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com

User avatar
VictorBorun
Captain
Posts: 1068
Joined: Fri Oct 16, 2020 10:25 pm

Re: APOD: The Phases of Venus (2024 Jan 08)

Post by VictorBorun » Mon Jan 08, 2024 6:15 pm

I wonder if the 3d and 4th crescents are shown in the wrong order

cmflyer
Ensign
Posts: 15
Joined: Fri Sep 26, 2008 4:33 am

Re: APOD: The Phases of Venus (2024 Jan 08)

Post by cmflyer » Mon Jan 08, 2024 8:55 pm

I wonder about the sliver crescent image. I would think that would only be "up" during the day.
cmflyer
Montana
USA

User avatar
Chris Peterson
Abominable Snowman
Posts: 18322
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: The Phases of Venus (2024 Jan 08)

Post by Chris Peterson » Mon Jan 08, 2024 8:58 pm

cmflyer wrote: Mon Jan 08, 2024 8:55 pm I wonder about the sliver crescent image. I would think that would only be "up" during the day.
It is easy to image (and even see visually) Venus when the Sun is above the horizon.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com