Advanced
Target Suggestion Tutorial
This tutorial will take
you through HiWeb and help you select a target location. This takes you through all of the
advanced options available on HiWeb.
If you just want to go through and select a site quickly, you can use
the Quick Start
or 10-step
tutorial. Below is a summary of
the steps you will need to take to suggest a target, you can also use this to
jump to a spot in the tutorial.
Good luck and have fun!
Target suggestion
summary:
Step-by-step
Instructions to Selecting a Target:
1.
When you open up the
HiRISE Image Suggestion Facility Webpage (HiWeb), you will see a bright
colorful map of Mars. This map has been created using data from Mars
Orbiter Laser Altimeter (MOLA), which is an instrument on the Mars Global
Surveyor. It has collected altimetric data from the entire surface of
Mars and shows the planet's highs and lows. Blue areas on the map are low
in elevation and reds are high. The very highest spots on the planet, the
tops of the volcanoes of Tharsis and Olympus Mons, are white. The lowest
area, in Hellas Planitia, is a deep purple.
2. You also have the option of seeing maps created with
other instruments, by selecting one from the top of the map. Try looking
at each of the maps. You will find that different features are more or
less clear using the various tools.
These tools are:
MDIM:
Mars Digital Image Models from the Viking Orbiters. Orbiters imaged the entire
surface of Mars at a resolution of 150 to 300 meters, and selected areas at 8
meters. This map is a mosaic of all of the images, and provides a
nice overview of the entire planet. Large features are clearly visible,
but the resolution is too poor to see smaller features like gullies or sedimentary layering.
MOC: Mars Orbiter Camera, which is onboard the Mars
Global Surveyor. Both wide-angle images and narrow angle images were taken
using this instrument. Wide-angle image resolutions range from ~2 to ~15
meters/pixel. The narrow-angle lens takes more detailed photos and can image
features as small as 0.5 meters (1.7 feet) across. Images from MOC are higher
resolution than MDIMs, but there is less coverage of the planet. So with
MOC images, you can see smaller features much better. The HiRISE images
will be able to image even smaller features, and HiRISE will be able to take
color photos.
MOLA: Mars Orbiter Laser Altimeter, which is an
instrument on the Mars Global Surveyor. This tool measured the height of
martian surface features like mountains and depths of valleys, producing
elevation maps precise to within about 30 centimeters (1 foot) in the vertical
dimension. This is particularly useful for looking at the polar caps,
seeing large canyons, impact craters and volcanoes.
TES: Thermal Emission Spectrometer, an instrument on the
Mars Global Surveyor. This instrument studies the atmosphere and maps the
mineral composition of the surface by analyzing infrared radiation, which scans
for heat emitted from the surface of Mars. This instrument is used to look at
the minerals on the surface of Mars and also to see if there are areas of high
heat flow, like you would see in a hydrothermal region, such as Yellowstone National
Park on Earth.
3. Once you have looked at the various maps of Mars,
select the one that helps you see the feature you are most interested in.
If you move your cursor around the map, you will see a box. This is the
area that will come up in the next page. Move your cursor to site you are
interested in and click it. A new window like the one below will pop up
with an MDIM surface image of the area.
Alternatively, if you know the latitude and longitude of the region you
are interested in, you can just type that into the box at the top and click
"Launch Image Suggestion Facility".
4. Again, you have the option of selecting which map
view you prefer at the bottom of the page. Turning the grid "on" will
provide you with the latitude and longitude grid. You can also select
"Information" to have a quicktip popup window explain the details on the
webpage. Clicking on "Gazetteer"
will provide you with information on place names, like in the window
below:
5. You can either click on the + and – to zoom in
and out, or you can click on one of the options under "Map
Scale". If you use the plus and minus buttons, the percent zoom and
resolution is to the right of the box. You can move the image by either
clicking on the arrow buttons, clicking on the image and holding the mouse
button down as you drag it, or by dragging the red box in the map at the lower
left to the area you want to look at.
6.
Once you have found the
area you are interested in, click on "Suggest HiRISE Target".
This window will pop up:
7. In this window you will see your zoomed-in image of
Mars and a series of buttons to the left. You can
click on the button "View Suggestions" to see if anyone has already
suggested the location you are interested in. You can find out the details about their request by
clicking on the blue outline of the suggested spot. A window will appear
with all of the details of the request. Close this window when you are
finished and return to the window shown above. On this page, you also have the option of clicking
"Gazetteer" to have the names of features come up and/or clicking on "Help" to
have the quicktips window appear.
8. To the far left at the top are two buttons,
"MOC/THEMIS" and "Map Display". If you click on the
"MOC/THEMIS" button, it will allow to you see the more detailed
images from MOC or THEMIS. THEMIS is the Thermal Emission Imaging System,
a camera on Mars Odyssey that images Mars in the visible and infrared parts of
the spectrum. This instrument is used to take photos of the planet and
also to determine the distribution of minerals on the surface of Mars. The IR
resolution of the instrument is 100 meters (328 feet) per pixel. Using visible
imaging in five spectral bands, the experiment also takes 18-meter-resolution
(59-foot) images.
10. After experimenting with this, and seeing what
high-resolution images have already been taken of the area using MOC and
THEMIS, you can return to "Map display" by clicking the button at
the top.
13. The "Elevation Profiler" button allows you
to view an elevation map of the area, create a graph of the elevation of a cross-section, and view MOC images. Click on
this button and a new window will appear like the one below. By clicking on the
image, it will open up in another new window that you can print. If you
want to look at an elevation profile, load either half- or full-resolution data
by clicking either of the two buttons on the left, then click the "Create
Profile" button. Then click on the screen where you want the profile
to start and click at the point where you want it to end. Then click the
mouse again or click the "Create Profile" button again to plot the line
on the graph. Below, you can see two profiles have been created showing the
topography of Olympus Mons. You can make as many profiles as you like, or press
"Clear Profiles" to start over again.
14. You can also display the map in this window using
MDIM images or using the MOLA data. By selecting "local" for
elevation color, the color range from black to white is based on the elevation
only within the image. Global elevation color maintains the same color
range that is representative of the entire planet, so white is the elevation of
the highest places on the planet, and black is the lowest. If you want to
compare multiple locations, you will probably want to use "global"
colors, but if you want to see more subtle changes in topography, use
"local". This will not affect your profiles. You can also
change the length of the X-axis to fit your profiles.
15. You can see the narrow and wide angle MOC images on
this screen as well. Click "Display MOC images" and select
either narrow or wide. Then you can click on the boxes to see the image.
The boxes for the wide-angle MOC images represent the center of the
image. If you move your cursor over the box, you will see the full extent
of the image. You can chose to select just the image or go to the
webpage, which has additional information about the image and download
options. When you are finished you can close the window and return to the
"Map Display/Suggestion" page.
16.
Now you can select the
area that you think should be imaged. Click "Suggest HiRISE
Target". If you are a new user, you will have to create a user name
and password. Do this by clicking the "Register" button at the
right of the window that pops up:
17. Fill in the registration form.
19.
Leave this window open,
but return to the "Map Display/Suggestion" page to select the area
you wish to image. Under the button "Suggest HiRISE Target" you
can choose either "image footprint" or "polygon". Image footprint will give
you a parallelogram by clicking on the image and
dragging the cursor or by simply clicking on the page. If it is not in
the correct place, you can drag this parallelogram to the area you wish to
image. If you chose polygon you can define the boundaries with any
shape. Click the mouse at the edges of the polygon and double-click the
mouse at the end. You have now selected the area to be
imaged.
20. The parameters will automatically be entered into the
orange HiRISE suggestion form window under General parameters.
21. At the right side of the window is an area labeled
"Your Priority". If you are selecting a number of locations,
chose which ones are the highest priority for you. 1 is low priority, and
5 is high. Remember that not all of the suggested locations can be imaged,
so chose your high priority locations carefully.
22.
Next go to Science
Justification, just below the General Parameters on the same window, and select
a "Primary Science Theme". This allows you to chose the scientific
area that best applies to the reason for your selection. For example, if
you think that the area you selected may be an interesting ancient river bed,
you would select "Fluvial Processes". Alternatively, if you are
looking at growth or recession of the polar caps, you may select "Glacial
Geology" as your primary theme and "Climate Change" as your
secondary theme. This then tells us where this request should be
sent. Each science theme has a different scientist that will select the
best suggestions to be imaged. Only a primary science theme is required.
Here is a brief
description of what each of these scientific areas cover. Click on the
term to go to a link with more information about the scientific
specialty.
v Climate
Change: any features, deposits or
landforms indicative of changing climatic regimes.
v Eolian Processes: refers to features or processes involving wind
erosion or deposition. Examples include: dunes, wind streaks, dust
devils.
v Fluvial Processes:
refers to surface and subsurface water flow processes involving the formation
and subsequent development of channels, rivers or streams and the valley
systems in which they flow or once flowed. Water is critical for life as
we know it, so the presence of water in streams or gullies on Mars suggests
that there was water on the surface of Mars at one point. Persistent
surface and subsurface water flow could have potentially created habitable
regions in the planet's past.
v Future
Exploration/Landing Sites:
Understanding past landing sites from orbit or to target areas of potential
future landing sites for further study.
v Geologic Contacts/Stratigraphy: refers to the description, correlation, classification of stratigraphic
layers and their depositional environments. Also refers to the geologic
boundaries between two different layers, surface units, materials, or features.
v Glacial Processes: refers to the landforms, features and materials
produced by glacial or ice sheet activity. Examples include: moraines, eskers,
kettles, kames.
v Hydrothermal Processes: refers to processes involving hot ( or above
ambient temperature) water at or near the surface. Many hydrothermal
areas have been heated by hot magma bodies beneath the surface of the planet,
such as the hot springs in Yellowstone National Park on Earth. There may
have been significant hydrothermal activity near the volcanoes or impact
craters on Mars in the past.
v Impact Processes: refers to the
processes involved in meteorite impacts and the subsequent formation of impact
craters and basins and related features to the surface of the planet.
v Landscape Evolution: different landforms and processes that affect the
overall changes in a regions or landscape's shape and elevation over time. Many
of the features on Mars look similar to those seen on Earth, but many are quite
different. Understanding the origin of the unusual features can tell us
about the history of the planet.
v Mass Wasting Processes: refers to the movement of sediment and rock material downslope by
gravitational forces. Downslope movement may be slow as in creep and
solifluction or may be rapid as in landslides, rockfalls, rockslides and debris
flows.
v Periglacial Processes: refers to landforms or features that form at the
margins of former and existing ice sheets and glaciers. Environments where
frost action is important and induced by a periglacial climate beyond the
margin of an ice sheet. Such landforms include: pingos, polygons, and a
variety of patterned ground.
v Polar Geology: (detailed version) studies of the polar caps.
Understanding the polar caps on Mars can help us better understand past climate
changes on Mars.
v Seasonal Processes: refers to any processes, landforms or features that
change with the season. Examples include: the sublimation of the polar
ice caps, presence of seasonal frosts, landforms or features that change shape,
color or are present with the season.
v Sedimentary/Layering Processes: refers to the deposition or erosion of sediment
layers in lakes or oceans, layers formed by deposition of ash from volcanic
eruptions or layers from cyclic changes in the amount of dust in the
atmosphere.
v Surface Properties: refers to understanding the physical and chemical
composition of the surface. For example: the nature and abundance of rocks on
the surface and the materials that comprise the surface.
v Tectonic Processes: refers to
deformation of the planets surface into fractures, lineaments, grabens and
faults caused compression, shearing or expansion of the planet's crust by
volcanic, impact or sedimentary processes.
v Volcanic Processes: (detailed
version) refers to the processes involved in volcano formation and
lava emplacement on the surface of the planet. Much of Mars is covered in
volcanic rocks, and ancient lava flows can be observed over much of the
planet. Volcanoes also greatly affect the atmosphere due to the eruption
of gasses, and this could have had a large impact on past climate.
23. Next, under "Science Rationale," type in a
brief explanation of why you think this is an important place to collect an
image. For example, you may say, "this area is a potential lake bed, and
we are interested in seeing evidence of layering or platforms along the lake
margins."
24. Next you may select specific parameters for the
camera. At the top of the HiRISE Suggestion Form, click on "Special
Requests". Here you can select the resolution of the photo you would
like to take. Resolution refers to the sharpness or clarity of the image.
The lowest resolution option is 1.2 m/pix, and the highest resolution is 0.3
m/pix. For more information on Resolution and Binning, go
to this page. You may be tempted to select the highest resolution,
but keep in mind that there is a limit to the amount of data that can be
stored, and the higher the binning (and lower resolution), the more images that
can be obtained. So you will also need to justify your reasons if you
want the highest resolution and give it a priority of 1 (lowest) to 5
(highest). On this page you can also decide if you need color or stereo images.
You would select "stereo needed" if you wanted two photos from two
opposing angles taken of the same location. This can then be used to
calculate height or depth of a feature and make 3-D images. Here, too, you will
need to provide a justification for needing it and give it a priority
value. Because only a very small
number of stereo pairs will be taken, any suggestion with "Stereo needed" will
automatically be given a lower priority, and only those that are the most
scientifically necessary will be taken.
Here is a brief
description of the terms used for the seasons:
v Vernal
Equinox: start of Spring in the
northern hemisphere; most sunlight falls directly on the equator
v Winter
Solstice: when the north pole is in
continuous darkness and the south pole is in continuous daylight.
v Summer
Solstice: when the sun falls on the
north pole and it is in continuous daylight; the south pole is in continuous
darkness.
v Autumnal
Equinox: start of fall in the
northern hemisphere, sun falls directly on the equator.
27. You can later edit your suggestions by returning to
the HiRISE Target Suggestion webpage and going to the third page, where you
will see the "Login to Edit Suggestions" button at the top left side
of the screen.
Return to HiRISE Learning Page