Space Communications and Navigation Network Demonstration Overview

Introduction

The Space Communications and Navigation demonstration begins with a 3 dimensional view of the Earth from space. A welcome-to-the-demonstration screen is presented. Text appears that says, "Space Communications and Navigation Network Demonstration. Demonstration developed by NASA Ames IT on behalf of the Space Communications and Navigation (SCaN) Program Office / Space Operations Mission Directorate. Visit https://spacecomm.nasa.gov/ → for more information. Credit is given to Mannheim Steamroller and Dots and Lines, Ink, publisher, for use of the song 'Return' from the album The Music of the Spheres."

After a moment, the Flythrough begins.

Flythrough

The Flythrough begins by zooming out to a view of the Earth from space. Text onscreen says, "Press ESC to Skip the Flythrough." Pressing ESC will take the user to the Main Menu.

The text onscreen changes to say, "Space communication is critical to all NASA missions. Astronauts, mission controllers, and scientists depend upon the reliable transmission of information between the ground and spacecraft in low Earth orbit (LEO) or deep space."

The text changes to say, "Let's look at three of the networks that support space communication: the Near Earth Network, the Space Network, and the Deep Space Network."

The Near Earth Network is introduced with the text, "The Near Earth Network (NEN), formerly known as the Ground Network (GN), comprises globally distributed tracking stations that support near Earth spacecraft needing periodic contact."

The text changes to say, "Communication on the Near Earth Network originates at an antenna on the ground."

The user view zooms to McMurdo Station and the text changes to read, "Data is sent directly to the target spacecraft as it passes overhead."

The view then zooms to the Ice, Cloud, and land Elevation Satellite (ICESat).

The view zooms back out to show the Earth from space.

The text introduces the Space network: "The Space Network (SN) consists of geosynchronous relay satellites predominantly supporting low Earth orbit missions."

The text changes to say, "Space Network communication originates at one of the ground segment's three facilities."

The view zooms into the White Sands Ground Terminal antenna and text changes to say, "The antennas of the Space Network's ground segment are fixed in alignment with the Tracking and Data Relay Satellite System (TDRSS) constellation."

The view flies into space to show the location of the eight TDRS satellites as yellow points in space. The text changes to read, "Data from the ground is relayed to a TDRSS satellite."

The user view then zooms into the TDRS 5 satellite and the text says, "The data is then sent from the TDRSS satellite to the target spacecraft."

The view flies to the International Space Station (ISS).

The view then zooms back out to show the Earth from space.

The Deep Space Network is introduced with the text, "The Deep Space Network (DSN) relies on globally distributed terrestrial communication stations to support missions operating at significant distances from Earth orbit."

The text changes to read, "Deep Space Network communication begins at an antenna on the ground, which can be rotated and directed at its target."

The view zooms in to Madrid Deep Space Communication Complex and the text changes to say, "In some cases, the transmission must go through a relay satellite. Communication with the Mars Rovers, for example, is relayed through the Mars Reconnaissance Orbiter (MRO)."

The view flies way out to zoom in on the Mars Reconnaissance Orbiter (MRO). The text explains that, "The MRO will relay the message when its orbit brings it into view of the Rover."

The view then zooms in to the Opportunity Rover.

The view flies back to Earth and stops at the view of the entire Earth.

The text changes to say, "Now let's take a closer look at the networks," as the view zooms toward Earth to arrive at the Network Control Center (NCC) and the Main Menu slides onto the screen. The camera orbits the NCC.

Main Menu

The user view shows a Network Control Center building. Overlaid on the right-hand side of the screen are eleven semi-transparent buttons. Nine buttons are labeled with the name of a spacecraft that the user can choose as a communication target; the two other buttons mute the audio and replay the Flythrough. The buttons are labeled:

When the user clicks one of the spacecraft buttons, the corresponding workflow begins.

Hubble Workflow

If the user clicks 1 - Hubble from the Main Menu then the Main Menu slides off the screen and is replaced by the TDRSS Scheduling Interface as the camera zooms out to a view of the whole planet. If the user confirms a communication time the view zooms into the ground station and the user is presented with a set of buttons under the heading "Choose imaging target:"

  • Ring Nebula [Ring Nebula (M 57)]
  • NGC 3132 [Eight-burst Nebula (NGC 3132)]
  • Crab Nebula [The Crab Nebula (M 1): a supernova remnant]
  • Hoag's Object [Hoag's Object: a peculiar ring-shaped galaxy]
  • V838 Mon [Light echo from erupting star V838 Monocerotis]
  • NGC 4622 [Spiral galaxy NGC 4622]
  • NGC 3310 [Starburst galaxy NGC 3310]
  • b - Back
If the Back button is clicked, the TDRSS Scheduling Interface screen is shown again.

The set of picture target buttons displayed depends upon which objects are visible to Hubble at the current simulation time. If one of the picture target button is clicked, the buttons disappear and the user view pulls away slightly and then there are many yellow circles representing data originating at the antenna and traveling into space. The user view then zooms into space and zooms in behind the TDRS satellite. The yellow data rings arrive at the TDRS satellite and then are sent to the Hubble Spacecraft closer to the Earth. The user view then zooms into the Hubble telescope and the Hubble telescope rotates to take a picture of the chosen target. The user view then zooms into space with grid lines indicating the camera focusing on an area to be photographed. The user view zooms into a deep space area of interest and then a picture frame flashes, indicating the picture was taken.

Next, the yellow data rings are sent from the Hubble to the TDRS and then from the TDRS back to the antenna on Earth. The image that was taken is displayed on the screen. Text appears that says, "Finished processing." Beneath it, buttons appear labeled "p - Print" and "b - Back". The print button prints out the image that was photographed by Hubble. The back button sets the camera in motion toward the Network Control Center Building and returns the user to the Main Menu.

Space Shuttle Workflow

If the user clicks 2 - Space Shuttle from the Main Menu then the Main Menu slides off the screen and is replaced by the TDRSS Scheduling Interface as the camera zooms out to a view of the whole planet. If the user confirms a communication time the view zooms into the ground station and the user is presented with the two buttons, which read "d - Dock Shuttle" and "b - Back". If the Back button is clicked, the TDRSS Scheduling Interface screen is shown again.

If the Dock Shuttle button is clicked then the buttons disappear and the user view pulls away slightly and then there are many yellow circles representing data originating at the antenna and traveling into space. The user view then zooms into space and zooms in behind the TDRS satellite. The yellow data rings arrive at the TDRS satellite and then are sent to the Space Shuttle Discovery closer to the Earth. The camera zooms into Discovery, which is positioned between the ISS and Earth.

The Space Shuttle begins to move toward the ISS, gradually turning its nose upward until the Space Shuttle meets the station. Meanwhile, radio transmissions can be heard in the background:

   "Houston and Alpha from Discovery, the fly-out looks good and we're initiating the final approach from 30 feet."
   "Alpha copies. We're ready."
   "Discovery, Houston copies. Initiating final approach."
   "Houston and Alpha, capture confirmed."
   "Discovery, Houston. On the big loop, station free drift confirmed."
   "Discovery copies."
   "And on the big loop Alpha sees we're in free drift also. Welcome to the Space Station, Discovery. We're glad you're here."

Next, the camera flies to the Network Control Center Building and returns the user to the Main Menu.

ISS Workflow

If the user clicks 3 - ISS from the Main Menu then the Main Menu slides off the screen and is replaced by the TDRSS Scheduling Interface as the camera zooms out to a view of the whole planet. If the user confirms a communication time the view zooms into the ground station and the user is presented with the two buttons, which read "d - Dock Shuttle" and "b - Back". If the Back button is clicked, the TDRSS Scheduling Interface screen is shown again.

If the Dock Shuttle button is clicked then the buttons disappear and the user view pulls away slightly and then there are many yellow circles representing data originating at the antenna and traveling into space. The user view then zooms into space and zooms in behind the TDRS satellite. The yellow data rings arrive at the TDRS satellite and then are sent to the ISS, which is closer to the Earth. The camera zooms in to the ISS, beneath which the Space Shuttle is visible.

The Space Shuttle begins to move toward the ISS, gradually turning its nose upward until the Space Shuttle meets the station. Meanwhile, radio transmissions can be heard in the background:

   "Houston and Alpha from Discovery, the fly-out looks good and we're initiating the final approach from 30 feet."
   "Alpha copies. We're ready."
   "Discovery, Houston copies. Initiating final approach."
   "Houston and Alpha, capture confirmed."
   "Discovery, Houston. On the big loop, station free drift confirmed."
   "Discovery copies."
   "And on the big loop Alpha sees we're in free drift also. Welcome to the Space Station, Discovery. We're glad you're here."

Next, the camera flies toward the Network Control Center Building and returns the user to the Main Menu.

Spirit Workflow

If the user clicks 4 - Spirit from the Main Menu then the Main Menu slides off the screen and is replaced by the DSN Scheduling Interface as the camera zooms out to a view of the whole planet. If the user confirms a communication time the view zooms into the ground station and the user is presented with the two buttons, which read "d - Drive Rover" and "b - Back". If the Back button is clicked, the DSN Scheduling Interface screen is shown again.

If the Drive Rover button is clicked then the view pulls out a bit and the ground station antenna rotates to align with the Mars Reconnaissance Orbiter. There are many yellow circles representing data that originate at the antenna and fly off into space. The camera zooms far out into space and the planets' orbits are drawn as colored circles. The yellow rings are visible traveling from Earth all the way to Mars. Next, the camera zooms in to the MRO. The signal can be seen reaching MRO. The camera pulls out to show all of Mars and rotates so that Spirit - indicated by a yellow dot - is in the center of the camera. Next, time advances until MRO can see Spirit. MRO is shown as a yellow dot orbiting Mars. The area visible to MRO is indicated by a thin, yellow circle drawn on the surface of Mars that follows MRO as it orbits. Once MRO is in range of Spirit the camera zooms in a little closer and MRO emits yellow rings that travel to Spirit. The camera zooms into Spirit, which moves forward a ways over the Martian terrain.

Next, the camera flies toward the Network Control Center Building and returns the user to the Main Menu.

Opportunity Workflow

If the user clicks 5 - Opportunity from the Main Menu then the Main Menu slides off the screen and is replaced by the DSN Scheduling Interface as the camera zooms out to a view of the whole planet. If the user confirms a communication time the view zooms into the ground station and the user is presented with the two buttons, which read "d - Drive Rover" and "b - Back". If the Back button is clicked, the DSN Scheduling Interface screen is shown again.

If the Drive Rover button is clicked then the view pulls out a bit and the ground station antenna rotates to align with the Mars Reconnaissance Orbiter. There are many yellow circles representing data that originate at the antenna and fly off into space. The camera zooms far out into space and the planets' orbits are drawn as colored circles. The yellow rings are visible traveling from Earth all the way to Mars. Next, the camera zooms in to the MRO. The signal can be seen reaching MRO. The camera pulls out to show all of Mars and rotates so that Opportunity - indicated by a yellow dot - is in the center of the camera. Next, time advances until MRO can see Opportunity. MRO is shown as a yellow dot orbiting Mars. The area visible to MRO is indicated by a thin, yellow circle drawn on the surface of Mars that follows MRO as it orbits. Once MRO is in range of Opportunity the camera zooms in a little closer and MRO emits yellow rings that travel to Opportunity. The camera zooms into Opportunity, which moves forward a ways over the Martian terrain.

Next, the camera flies toward the Network Control Center Building and returns the user to the Main Menu.

Cassini Workflow

If the user clicks 6 - Cassini from the Main Menu then the Main Menu slides off the screen and is replaced by the DSN Scheduling Interface as the camera zooms out to a view of the whole planet. If the user confirms a communication time the view zooms into the ground station and the user is presented with a set of buttons under the heading "Choose imaging target:"

  • Saturn [Saturn: the ringed planet]
  • Titan [Titan: the largest moon of Saturn]
  • Enceladus [Enceladus: a moon with ice geysers]
  • Iapetus [Iapetus: light and dark]
  • Tethys [Tethys, an icy moon of Saturn]
  • Rhea [Rhea: Saturn's second largest moon]
  • b - Back
If the Back button is clicked, the DSN Scheduling Interface screen is shown again.

The set of picture target buttons displayed depends upon which objects are visible to Cassini at the current simulation time. If one of the picture target buttons is clicked, the buttons disappear and antenna rotates to align with Cassini. The user view pulls away slightly and then there are many yellow circles representing data originating at the antenna and traveling into space. The user view then zooms far out into space. The planets' orbits are drawn as colored circles and a dot labeled Cassini is visible at a point near Saturn's orbit, the 6th ring out from the sun. There is a sense that Cassini is extremely far away. The yellow rings of the transmission continue to travel between the antenna and Cassini. The view then zooms into Cassini. The yellow data rings arrive at Cassini. Next, Cassini rotates to take a picture of the chosen target. The user view then zooms into space with grid lines indicating the camera focusing on an area to be photographed. The user view zooms into a deep space area of interest and then a picture frame flashes, indicating the picture was taken.

Next, the yellow data rings are sent from Cassini back to the antenna on Earth. The image that was taken is displayed on the screen. Text appears that says, "Finished processing." Beneath it, buttons appear labeled "p - Print" and "b - Back". The print button prints out the image that was photographed by Cassini. The back button sets the camera in motion toward the Network Control Center Building and returns the user to the Main Menu.

LCROSS Workflow

If the user clicks 7 - LCROSS from the Main Menu then the simulation time is set to October 29, 2009 04:17:11 PDT and the Main Menu slides off the screen to be replaced by two buttons, labeled "o - Observe Impact" and "b - Back". If the Back button is clicked, the Main Menu is shown again.

If the Observe Impact button is clicked then the camera zooms to the Goldstone Observatory antenna, which swivels to aim at LCROSS. Yellow communication rings are shown traveling from the antenna to LCROSS. The camera the zooms out toward the Moon and in to LCROSS while text on the screen says, "The main LCROSS mission objective was to confirm the presence or absence of water ice in a permanently shadowed crater near the lunar south pole. Water ice is a potential resource that could sustain future lunar exploration."

Next, the camera rotates around LCROSS to a view above the satellite looking down on the Moon. The text changes to say, "The LCROSS science payload consisted of two near-infrared spectrometers, a visible light spectrometer, two mid-infrared cameras, two near-infrared cameras, a visible camera and a visible radiometer."

The camera then flies along LCROSS's line of sight toward the Moon and zooms up to the Centaur rocket stage. The camera follows the rocket stage toward the Moon as the text onscreen reads, "On October 9, 2009 at 11:30 UTC, the LCROSS spacecraft observed the collision of a Centaur rocket stage with the Moon. LCROSS used its instruments to capture multiple complementary views of the debris plume."

A large dust cloud appears as the Centaur rocket stage impacts the Moon. The camera then swings back around to follow LCROSS as it too speeds toward the Moon. The text explains that, "LCROSS transmitted data from its observations of the Centaur impact for four minutes, until it too crashed into the Moon."

LCROSS is shown colliding with the Moon and then the camera flies back toward the Network Control Center Building and returns the user to the Main Menu.

ICESat Workflow

If the user clicks 8 - ICESAT from the Main Menu then the Main Menu slides off the screen and is replaced by the NEN Scheduling Interface as the camera zooms out to a view of the whole planet. If the user confirms a communication time the view zooms into the ground station and the user is presented with the two buttons, which read "r - Request Data" and "b - Back". If the Back button is clicked, the NEN Scheduling Interface screen is shown again.

If the Request Data button is clicked then the buttons disappear and antenna rotates to align with ICESat. The user view pulls away slightly and then there are many yellow circles representing data originating at the antenna and traveling into space. The user view then zooms into space and zooms in behind ICESat. The yellow data rings arrive at ICESat.

Text is displayed on screen that says, "ICESat stands for Ice, Cloud, and land Elevation Satellite. It will provide multi-year elevation data needed to determine polar ice sheet mass balance and cloud property information. It will also provide global topography and vegetation data. ICESat data produced this image of Antarctica's land and ice elevation."

Next a picture is drawn on screen for about 10 seconds. It shows a colorful elevation map-an example of a use for ICESat's data. It is streaked every which way with lines of varying color, each of which indicates a fly-over of ICESat. The key shows that the color of the line represents elevation in meters. The scale goes smoothly through the color spectrum from blue to red, which two colors represent elevations of 0m and 4000m respectively.

Next, the camera flies toward the Network Control Center Building and returns the user to the Main Menu.

Aura Workflow

If the user clicks 9 - AURA from the Main Menu then the Main Menu slides off the screen and is replaced by the NEN Scheduling Interface as the camera zooms out to a view of the whole planet. If the user confirms a communication time the view zooms into the ground station and the user is presented with the two buttons, which read "r - Request Data" and "b - Back". If the Back button is clicked, the NEN Scheduling Interface screen is shown again.

If the Request Data button is clicked then the buttons disappear and antenna rotates to align with Aura. The user view pulls away slightly and then there are many yellow circles representing data originating at the antenna and traveling into space. The user view then zooms into space and zooms in behind Aura. The yellow data rings arrive at Aura.

Text is displayed that says, "Aura has many sensors. One of them, the Ozone Monitoring Instrument (OMI) was recently used to track a volcanic eruption cloud as it drifted across the United States. Aura's measurements were then used to depict the amount of sulfur dioxide in the air."

Next a picture is drawn on screen for about 10 seconds. It shows a small section of a black and white map with dots marking Pullman and Vancouver. The map is overlaid with a grid running on the diagonal. Each cell in the grid is colored according to the amount of sulfur dioxide that Aura measured as it passed over that area. The key shows a band of color starting with white and then proceeding to blue and then all the way through the spectrum to red. The band is labeled to show that white indicates no sulfur dioxide was measured and red indicates that a large amount of sulfur dioxide was measured. The map has a small area marked with red cells and then a larger surrounding area marked with cooler colors.

Next, the camera flies toward the Network Control Center Building and returns the user to the Main Menu.

TDRSS Scheduling Interface

The user view shows Earth in the background. There are green arrows indicating the locations of TDRSS ground stations. On screen is a large box, in which is drawn a scheduling interface. Above the box is a prompt that reads "Select time for communication:". Inside the box, the scheduling interface graphically depicts the availability of each of the TDRSS satellites as a series of horizontal bars that overlay a timeline. The satellites are labeled from top to bottom of the left side of the box. Initially the timeline is empty, showing only a date at the top, and a series of horizontal lines with tick marks that denote four-hour increments.

There is a message that says "Getting Visibility Information from Flight Dynamics Facility" that is displayed for approximately 2 seconds as green horizontal bars are drawn to the right of each TDRS label. Next, there is a message that says "Getting scheduling information from Network Control Center" as a series of shorter red bars are drawn in places over the green bars.

There is a key showing that green bars indicate that the satellite is available at a given time, and that red bars indicate that there is a conflict at that time. To the right of the key are two buttons that advance the timeline forward or backward. When these buttons are clicked the timeline is redrawn as before and the Earth spins forward or backward accordingly. The legend explains that "Communication can only take place when the spacecraft is visible to a network node. Periods of visibility are determined by the spacecraft's orbit and Earth's rotation."

There is text below the box that says, "Press Enter to automatically select a time." There is a semi transparent button below the text that reads "b - Back". The Back button takes the user back to the Main Menu.

If the user presses Enter or clicks in a green area, the scheduling interface is cleared and the view swings around to center on the ground station that will be used for communication. Then the view shows time advancing to the chosen communication time. The chosen spacecraft can be seen orbiting Earth as it rotates. The camera then zooms into the target ground station, depicted as a large satellite antenna, and the spacecraft's workflow continues.

Spacecraft that use the Space Network include:

DSN Scheduling Interface

The user view shows Earth in the background. There are green arrows indicating the locations of DSN ground stations. On screen is a large box, in which is drawn a scheduling interface. Above the box is a prompt that reads "Select time for communication:". Inside the box, the scheduling interface graphically depicts the possible communication times as a series of horizontal bars that overlay a timeline. Three DSN ground stations are labeled from top to bottom of the left side of the box: Goldstone, Canberra, and Madrid. Initially the timeline is empty, showing only a date at the top, and a series of horizontal lines with tick marks that denote four-hour increments.

There is a message that says "Getting Visibility Information JPL Nav" that is displayed for approximately 2 seconds as green horizontal bars are drawn to the right of each ground station label. Next, there is a message that says "Getting scheduling information from Network Control Center" as a series of shorter red bars are drawn in places over the green bars.

There is a key showing that green bars indicate that communication is possible at a given time, and that red bars indicate that there is a conflict at that time. To the right of the key are two buttons that advance the timeline forward or backward. When these buttons are clicked the timeline is redrawn as before and the Earth spins forward or backward accordingly. The legend explains that "Communication can only take place when the spacecraft is visible to a network node. Periods of visibility are determined by the spacecraft's orbit and Earth's rotation."

There is text below the box that says, "Press Enter to automatically select a time." There is a semi transparent button below the text that reads "b - Back". The Back button takes the user back to the Main Menu.

If the user presses Enter or clicks in a green area, the scheduling interface is cleared and the view swings around to center on the ground station that will be used for communication. Then the view shows time advancing to the chosen communication time. The camera then zooms into the target ground station, depicted as a large satellite antenna, and the spacecraft's workflow continues.

Spacecraft that use the Deep Space Network include:

NEN Scheduling Interface

The user view shows Earth in the background. There are green arrows indicating the locations of NEN ground stations. On screen is a large box, in which is drawn a scheduling interface. Above the box is a prompt that reads "Select time for communication:". Inside the box, the scheduling interface graphically depicts the possible communication times as a series of horizontal bars that overlay a timeline. Four DSN ground stations are labeled from top to bottom of the left side of the box: ASF, MILA, Wallops, and McMurdo. Initially the timeline is empty, showing only a date at the top, and a series of horizontal lines with tick marks that denote four-hour increments.

There is a message that says "Getting Visibility Information from Flight Dynamics Facility" that is displayed for approximately 2 seconds as green horizontal bars are drawn to the right of each ground station label. Next, there is a message that says "Getting scheduling information from Network Control Center" as a series of shorter red bars are drawn in places over the green bars.

There is a key showing that green bars indicate that communication is possible at a given time, and that red bars indicate that there is a conflict at that time. To the right of the key are two buttons that advance the timeline forward or backward. When these buttons are clicked the timeline is redrawn as before and the Earth spins forward or backward accordingly. The legend explains that "Communication can only take place when the spacecraft is visible to a network node. Periods of visibility are determined by the spacecraft's orbit and Earth's rotation."

There is text below the box that says, "Press Enter to automatically select a time." There is a semi transparent button below the text that reads "b - Back". The Back button takes the user back to the Main Menu.

If the user presses Enter or clicks in a green area, the scheduling interface is cleared and the view swings around to center on the ground station that will be used for communication. Then the view shows time advancing to the chosen communication time. As Earth rotates, the target spacecraft is shown in orbit. A thin, yellow circle is drawn on the ground with the spacecraft in the center. The circle follows the spacecraft as it orbits, representing the area visible to the spacecraft. When the chosen time is arrived at it is clear that the ground station is in range of the spacecraft. The camera then zooms into the target ground station, depicted as a large satellite antenna, and the spacecraft's workflow continues.

Spacecraft that use the Near Earth Network include: