Figure 1. Deimos, Phobos By Curiosity. (C) NASA
All images in this article are courtesy NASA and JPL, and are in the public domain.



Sol Sun

MercuryMercury ____________

VenusVenus crescent

Earth &
Earth's Moon

Mars Mars: Spirit 
       Sol 30 ____________

Asteroids Vesta

Jupiter Jupiter storm 
       north of Great Red Spot ____________

Saturn Saturn's Rings

Uranus Uranus' Rings

Neptune Neptune

Pluto & Pluto Kuiper Belt

Comets &
Oort Cloud

Comments & Submissions ____________

Curiosity Photographs Moons, Asteroids

By F. E. Harris

September 14, 2014, with later edits.


On Sol 741, the Mars rover Curiosity turned its Mastcam to the night sky and took four photographs, two with its right camera, and two with its left. When I downloaded the pictures and viewed them at full resolution, it was immediately apparent that these were pairs of photos, taken at slightly different times, that could be used to identify the motions of the moons of Mars, comets, asteroids, planets, or all of these objects.

(Edit: I have made inquiries at JPL, and NASA has said only that these are not yet pictures of the comet.) At first I thought these were pictures of a large asteroid, with some smaller ones caught by accident, but then I thought the object appeared to have a tail, and it was most likely Comet Siding Spring. Inquiries at JPOL revealed the Mast Cameras do not have that much magnification. This is almost certainly Mars' larger moon, Phobos.

When looking at these picture I recommend that you download the full sized images by option clicking on them, each in its own tab, and then switching back and forth between them. You will see the features that move over time. These are moons, asteroids, or planets. The left camera pictures also appear to be stacked exposures, where the camera shutter was opened and shut several times during the taking of the picture, resulting in asteroids appearing as lines of dots.

In the thumbnails in the article, I have added squares around the moons, planets, or asteroids that I have spotted in the pictures, but I have left the full sized originals unchanged. You can reach the originals by clicking on the pictures. Open each in its own tab for best results.


Section 1: Right Camera

Curiosity Night Sky Photo
Figure 2. Curiosity Sol 741. Mastcam: Right 2014-09-06 18:00:19 UTC. (C) NASA/JPL

Curiosity Night Sky Photo
Figure 3. Curiosity Sol 741. Mastcam: Right 2014-09-06 18:14:03 UTC. (C) NASA/JPL

The bright moving object is very prominent, toward the right center of these images. I've put red boxes around the object in the thumbnails. Click on the pictures to see full sized, without boxes.

It really helps to put your finger on the screen next to the suspected moving dot, while clicking back and forth. That fixed point of reference helps a lot to see the movement.

In the lower left of the first frame there is a fainter object that disappears in the second frame. This is almost certainly an asteroid.


Section 2: Left Camera

Curiosity Night Sky Photo
Figure 4. Curiosity Sol 741. Mastcam: Left 2014-09-06 18:00:23 UTC (C) NASA/JPL

Curiosity Night Sky Photos
Figure 5. Curiosity Sol 741. Mastcam: Left 2014-09-06 18:14:15 UTC (C) NASA/JPL

The bright moving object is less prominent, toward the left center of these images. I've put red boxes around the object in the thumbnails. Click on the pictures to see full sized, without boxes. I've also put a green box around several linear sets of dots that appear to be asteroids. They are visible in both left images, suggesting that these may be stacked images, and the dots might be asteroids. There are several, less bright sets of 6 dots elsewhere in these images, which might also be faint asteroids.

There are also a pair of faint objects that move, very near the top left corner of the left pair of images. They are almost certainly more asteroids.

Edit: At the recent NASA social at JPL, one of the scientists mentioned that the rovers were doing test pictures at night, in preparation for the arrival of Comet Siding Spring, but that they had not yet gotten pictures of real science value. In addition to using the mast cameras, the ChemCam was also used, since it includes a very high magnification telescope. Here are links to the second set of pictures:

ChemCam Images:

MastCam Images:

Even More Recent MastCam Images:

It's kind of exciting to watch science unfold in real time.


1. "NEOWISE Spies Comet C/2013 A1 Siding Spring a Second Time," Mars Exploration Images, 08.07.2014 ,
2. "Curiosity Rover Raw Images: Mastcam," Mars Science Rover Curiosity, 2014-09-06.
3. "Mastcam: Left 2014-09-06 18:14:15 UTC,"
4. "Mastcam: Right 2014-09-06 18:14:03 UTC."
5. "Mastcam: Left 2014-09-06 18:00:23 UTC."
6. "Mastcam: Right 2014-09-06 18:00:19 UTC."
Off TopicFunny Pictures from Orbit

© 2011 F. E. Harris for Hypertek Publications. All Rights Reserved.