Help Shape the Future of Space Exploration

Join The Planetary Society Now  arrow.png

Join our eNewsletter for updates & action alerts

    Please leave this field empty

Headshot of Emily Lakdawalla

An opportunity for Spirit to see Earth and Venus together?

Posted by Emily Lakdawalla

26-09-2005 8:16 CDT

Topics: astronomy by planetary missions, Mars, Mars Exploration Rovers, Spirit

I received the following question by email last week:

"Do you know if the Mars rovers team has any plans to photograph Venus and Earth together in the evening sky from either rover site? They will be closest together around Sept. 29th."

I checked the Solar System Simulator, and here's what the sky would look like to Spirit on September 29.

Earth and Venus as Seen from Spirit on September 29, 2005

Earth and Venus as Seen from Spirit on September 29, 2005

The view is set to Spirit's Pancam 16.8-degree field of view. Earth and Venus would be two crescents of light in the sky. Pancam wouldn't be able to see their color, because they generally use their panchromatic filter and not color filters to do astrophotography -- it allows them to keep exposure times short.

The question seemed like a good one so I forwarded it on to Texas A & M researcher Mark Lemmon, whom I know is interested in things in Spirit's sky. Here's what he had to say.

"Sadly, we don't have such plans. This was a neat picture we identified a while back when we surveyed astronomical options. Unfortunately, the planets are too close to the Sun right now. We know from experience and modeling that we can see Earth when the Sun is at least 15 degrees below the horizon and the Earth is at least that far above. It gets better when there is less dust in the sky, and worse when there is more. Now, we cannot get a color image of the Earth or Venus, and I think we cannot even get a monochrome image. My initial hope was a different conjunction--Earth passed within one degree of Jupiter in June while near greatest elongation from the Sun and close to maximum brightness. However, before that happened, the worst and longest of our dust storms hit. Not only did we not have the power for the observation, but the dust was so bad that we wouldn't have seen the planets anyway. So, for now we are stuck observing things farther from the Sun or brighter than the Earth. A few more moon images are planned, then possibly a lunar eclipse or two, and if we still have surplus power in a month or so we may see a meteor shower. While our power situation may be worse, we have another chance (Earth + Jupiter + maybe Venus) in February or so--at a time when Mars tends to be less dusty."

Too bad about the Earth and Venus shot, but I am greatly enjoying all the other astronomical photos that Spirit has been taking.

See other posts from September 2005


Or read more blog entries about: astronomy by planetary missions, Mars, Mars Exploration Rovers, Spirit


Leave a Comment:

You must be logged in to submit a comment. Log in now.
Facebook Twitter Email RSS AddThis

Blog Search


Advocate for Space!

Fifteen years ago, Society members and passionate space advocates like you helped save the Pluto mission. Now we can do the same for missions to Europa and Mars.

Join over 27,600 people who have completed their petition and consider a donation to support advocacy efforts.

Sign Our Petition

Featured Images

Blue Origin New Shepard after first landing
New Shephard test flight and booster landing
Suni Williams and Doug Hurley in Crew Dragon
SpaceX Falcon 9 and Crew Dragon on pad 39A
More Images

Featured Video

MISSIONS: Dawn In The Asteroid Belt With Marc Rayman

Watch Now

Space in Images

Pretty pictures and
awe-inspiring science.

See More

Selfies to Space!

Take flight with a selfie on LightSail™ in 2016!

Send a Selfie Now

Connect With Us

Facebook! Twitter! Google+ and more…
Continue the conversation with our online community!