# Are there any photos of the Martian terminator from low Mars orbit?

This photo of Earth was taken from the ISS, an altitude of 211 nautical miles.

This photo of Mars was taken 71,000 kilometers above Mars (about 10 Mars diameters away).

Are there any images of the Mars terminator similar to the first image, of Earth?

This image of Mars is simulated,

PERSPECTIVE VIEW OF MARS: GALE ON THE TERMINATOR In this simulated view of Mars, Gale crater

You can find hundreds if not thousands of such photos by using the Planetary Data System search engine. Although most are not that "pretty".

Here's a sample query for Mars, Mars Reconnaissance Orbiter, and Terminator.

One of the images returned has this label

DATA_SET_ID                    = "MRO-M-HIRISE-2-EDR-V1.0"
DATA_SET_NAME                  = "MRO MARS HIGH RESOLUTION IMAGING SCIENCE
EXPERIMENT EDR V1.0"
PRODUCER_INSTITUTION_NAME      = "UNIVERSITY OF ARIZONA"
PRODUCER_ID                    = "UA"
PRODUCER_FULL_NAME             = "ALFRED MCEWEN"
OBSERVATION_ID                 = "PSP_009714_3065"
MRO:COMMANDED_ID               = "PSP_009714_3065"
PRODUCT_ID                     = "PSP_009714_3065_BG12_0"
PRODUCT_VERSION_ID             = "1"
SOURCE_FILE_NAME               = "4A_01_4897CA6500_04_0_01.DAT"
INSTRUMENT_HOST_NAME           = "MARS RECONNAISSANCE ORBITER"
INSTRUMENT_HOST_ID             = "MRO"
INSTRUMENT_NAME                = "HIGH RESOLUTION IMAGING SCIENCE EXPERIMENT"
INSTRUMENT_ID                  = "HIRISE"
TARGET_NAME                    = "MARS"
MISSION_PHASE_NAME             = "PRIMARY SCIENCE PHASE"
ORBIT_NUMBER                   = 9714
RATIONALE_DESC                 = "Sample - northern terminator"
SOFTWARE_NAME                  = "HiRISE_Observation v2.10.4 (2.44 2007/06/13
01:05:33)"
FLIGHT_SOFTWARE_VERSION_ID     = "IE_FSW_V4"


and looks like this:

Here is an image of Mars from an altitude of about 200 statute miles, I suppose. Unfortunately I don't know its precise altitude and which probe shot it. There are hardly descriptions of it.

• Can you annotate the image to show the terminator? The question asks for a picture of the terminator. – Organic Marble Mar 23 '20 at 12:28
• @OrganicMarble I don't know, there's little description of that image coursing throughout the web. – user35272 Mar 23 '20 at 13:07
• National Geographic says this is a Viking image and Universe Today says "...taken by the Viking 1 orbiter in June 1976." Forbes says "Image credit: NASA/Viking 1". While this is not really an image of the terminator, it's getting close; at the bottom right we see that the sides of tall features facing us are dark. – uhoh Mar 23 '20 at 21:41
• – uhoh Mar 23 '20 at 22:00
• @uhoh Thank you for asking, you lifted the riddle. I knew the image is quite old. We see the large shadows of the mountains so the terminator is obviously close as you say. – user35272 Mar 24 '20 at 6:47