Here’s another chance to play geographical detective! These four images from the
Multi-angle Imaging SpectroRadiometer (MISR) cover the same geographic area but
were acquired on four different dates. Each image was acquired by MISR’s
vertical-viewing (nadir) camera and encompasses an area measuring 257 kilometers
x 195 kilometers. North is toward the top.
This mystery concerns a small island located near the western edge of the
observed area. In the top two images, the island presents an obstacle to the
westerly winds, and wake patterns in the cloud layers are visible downstream of
the island’s location. In the lower left image, the island is visible within a
relatively clear area of open ocean. In the lower right image, the island is
partially obscured by cumulus clouds, and a spiral cloud pattern associated with
an atmospheric depression is visible in the southeast quadrant.
The Terra satellite, with MISR aboard, flies in a polar orbit and daylight
images such as these are acquired as the spacecraft flies from north to south.
Terra’s orbit is “sun-synchronous”, and when the satellite crosses the daylight
equator the local time beneath the spacecraft is approximately 10:30 a.m. The
four images shown here were processed identically, and relative variations in
brightness between the different views have been preserved.
Using any reference materials you like, please answer the following 5
The images contain multiple clues that can be used to determine whether
the observed area is situated in the northern or southern hemisphere. Name the
hemisphere and describe at least two clues you used to establish your answer.
(Clues should not make use of knowledge of the island’s identity.)
Three of the following four statements about the island’s environment are
true. Which one is false?
A. Glaciers cover most of the island, and vegetation
is limited to lichens and mosses.
B. The island is of volcanic origin and
located at the intersection of oceanic ridges.
C. A colony of Atlantic puffins
makes the island its home.
D. The highest peak rises more than 750 meters above
Three of the following four statements about the history of the island are
true. Which one is false?
A. Sovereignty over the island was transferred from
one country to another sometime between 1918 and 1932.
B. Steep cliffs make the
island difficult to access, and despite many attempts the first landing did not
take place until the 1850’s.
C. In the 19th century, a whaling/sealing
expedition christened the island with the name of a city located in their native
D. The earliest documented discovery of the island was by an 18th
century French explorer, and the island is currently named after this
All five of the following events took place, but only four occurred during
the second half of the 20th century. Which one did not occur in this time
A. The island and adjacent waters were designated a nature reserve.
weather station was established on the island, providing automated temperature
and pressure data.
C. A nuclear bomb test occurred within 3000 kilometers of the
D. An abandoned boat of unknown origin was discovered on the island. E.
The island’s seals were declared to be protected species.
What is the name of the island and to which country does it belong?
Answers will be published on the MISR web site (
http://www-misr.jpl.nasa.gov) in conjunction with the next weekly image release.
The names and home towns of respondents who answer all questions correctly by
the deadline will also be published in the order responses were received. The
first 3 people on this list who are not affiliated with NASA, JPL, or MISR and
who did not win a prize in the last quiz will be sent a print of the image.
A new “Where on Earth...?” mystery appears as the MISR “image of the week”
approximately once per month. A new image of the week is released every
Wednesday at noon Pacific time on the MISR home page. The image also appears on the Atmospheric Sciences Data Center
home page, http://eosweb.larc.nasa.gov/, though usually with a several-hour
The ghostly white shapes northeast and immediately southwest of Wrangel Island are sea ice. Over the course of the satellite record, Arctic sea ice has advanced and retreated past Wrangel Island many times. From 1979 to 2000, the sea ice edge at the end of summer generally fell somewhere in the vicinity of Wrangel Island, but this is not the first summer when the sea ice edge has retreated well north of the island.