CGI Parameter Reference

This document catalogs every CGI environment variable that the web forms can send to the three tools (Viewer, Tracker, Ephemeris Generator), with every possible value listed explicitly. It is derived from the SHTML form definitions in web/tools/. When the package is installed via pip, copy those files to a target directory with: install_ephemeris_tools_files /path/to/htdocs/tools.

The Perl newcgi.pm module parses the query string and exports each key=value pair as an environment variable. The FORTRAN binary (or, now, the Python --cgi mode) reads these environment variables directly.

PREFIX is an optional string prepended to CGI environment variable names to distinguish mission-specific forms from Earth-based forms. When the form is for Earth (no mission), PREFIX is empty. Examples of non-empty PREFIX include "Cassini" and "JUICE/"; variables then appear as PREFIXvariable or PREFIX/variable depending on usage. The newcgi.pm module sets these environment variables; the Viewer, Tracker, and Ephemeris Generator tools read them. Conditional parameter availability and possible values throughout this document depend on whether PREFIX is empty or set (e.g. xunit and body lists).

General Notes

Whitespace in <option> values

Many <select> options in the SHTML forms include leading whitespace before the display text (e.g. <option> arcsec). Because <option> elements without an explicit value attribute use their text content as the submitted value, browsers may send values with variable leading whitespace. The newcgi.pm CGI wrapper and/or the backend should strip leading/trailing whitespace before interpreting values. In this document, values for <select> parameters include a single leading space when the original HTML has at least one space after the <option> tag. Some values (e.g. time_unit) are listed without the space for readability; the backend should handle both forms.

HTML input constraints

The HTML maxlength attribute on text inputs limits client-side entry length. These are not enforced by the backend but represent the expected input size:

  • 50 characters: start, stop, interval, time, fov, center_ra, center_dec, center_star, latitude, longitude, altitude, moonpts, peripts, arcpts, extra_ra, extra_dec, extra_name

  • 60 characters: title

  • 20 characters: xrange, torus_inc, torus_rad

Output line limit

The ephemeris generator enforces a maximum of 10,000 output lines per request (noted in the help pages for all planets).

Multi-valued parameters

When multiple checkboxes share the same name attribute (e.g. moons, columns, mooncols, rings, other), the newcgi.pm CGI wrapper joins their values with # into a single environment variable. For example, selecting Io and Europa produces:

moons=001 Io (J1)#002 Europa (J2)

Viewer Parameters

All viewer forms submit to viewer3_xxx.pl (now viewer3_xxx.sh).

Metadata (consumed by the CGI wrapper, not the backend)

abbrev (hidden)

Identifies the planet and optional mission prefix.

Possible values:

  • "sat"

  • "jup"

  • "ura"

  • "nep"

  • "plu"

  • "mar"

  • "satc"

  • "jupc"

  • "jupj"

  • "jupjc"

  • "jupnh"

  • "jupec"

  • "plunh"

version (hidden)

Form version string.

Possible values:

  • "3.1"

output (radio)

Output format.

Possible values:

  • "HTML"

  • "PDF"

  • "JPEG"

  • "PS"

submit (submit button)

Always "Render diagram". Ignored by the backend.

Ephemeris Selection

ephem (hidden)

SPICE kernel selection string. The leading three-digit number is the version code (000 = latest); the rest describes the kernel files.

Possible values:

  • "000 MAR097 + DE440" (Mars)

  • "000 JUP365 + DE440" (Jupiter, non-New-Horizons)

  • "000 JUP344 + JUP365 + DE440" (Jupiter, New Horizons)

  • "000 SAT415 + SAT441 + DE440" (Saturn)

  • "000 URA111 + URA115 + DE440" (Uranus)

  • "000 NEP095 + NEP097 + NEP101 + DE440" (Neptune)

  • "000 PLU058 + DE440" (Pluto)

Observation Time

time (text)

Free-text datetime string. Format: yyyy-mm-dd hh:mm:ss. Required field.

Field of View

fov (text)

Numeric value for the field of view. Free text. Examples: ".005", "10", "0.5". Required field.

fov_unit (select)

Unit for the fov value. Note: all form values have a leading space due to HTML formatting.

Possible values (all planets):

  • "seconds of arc"

  • "degrees"

  • "milliradians"

  • "microradians"

  • "kilometers"

Planet-specific values (selected by default for each planet):

  • "Mars radii" (Mars)

  • "Jupiter radii" (Jupiter)

  • "Saturn radii" (Saturn)

  • "Uranus radii" (Uranus)

  • "Neptune radii" (Neptune)

  • "Pluto radii (1153 km)" (Pluto)

  • "Pluto-Charon separations (19,571 km)" (Pluto, default)

Instrument-specific values (only when PREFIX is empty or matches mission):

  • "Voyager ISS wide angle FOVs" (Jupiter, Saturn, Uranus, Neptune)

  • "Voyager ISS narrow angle FOVs" (Jupiter, Saturn, Uranus, Neptune)

  • "Galileo SSI FOVs" (Jupiter only)

  • "Cassini ISS wide angle FOVs" (Jupiter, Saturn)

  • "Cassini ISS narrow angle FOVs" (Jupiter, Saturn)

  • "Cassini VIMS 64x64 FOVs" (Jupiter, Saturn)

  • "Cassini UVIS slit widths" (Jupiter, Saturn)

  • "LORRI FOVs" (Pluto only)

Diagram Center

center (radio)

Center mode.

Possible values:

  • "body"

  • "ansa"

  • "J2000"

  • "star"

center_body (select, when center=”body”)

Body to center on. Leading space from HTML formatting.

Mars:

  • "Mars"

  • "Phobos (M1)"

  • "Deimos (M2)"

Jupiter:

  • "Jupiter"

  • "Io (J1)"

  • "Europa (J2)"

  • "Ganymede (J3)"

  • "Callisto (J4)"

  • "Amalthea (J5)"

  • "Thebe (J14)"

  • "Adrastea (J15)"

  • "Metis (J16)"

Saturn:

  • "Saturn"

  • "Mimas (S1)"

  • "Enceladus (S2)"

  • "Tethys (S3)"

  • "Dione (S4)"

  • "Rhea (S5)"

  • "Titan (S6)"

  • "Hyperion (S7)"

  • "Iapetus (S8)"

  • "Phoebe (S9)"

  • "Janus (S10)"

  • "Epimetheus (S11)"

  • "Helene (S12)"

  • "Telesto (S13)"

  • "Calypso (S14)"

  • "Atlas (S15)"

  • "Prometheus (S16)"

  • "Pandora (S17)"

  • "Pan (S18)"

  • "Methone (S32)"

  • "Pallene (S33)"

  • "Polydeuces (S34)"

  • "Daphnis (S35)"

  • "Anthe (S49)"

  • "Aegaeon (S53)"

Uranus:

  • "Uranus"

  • "Miranda (U5)"

  • "Ariel (U1)"

  • "Umbriel (U2)"

  • "Titania (U3)"

  • "Oberon (U4)"

  • "Cordelia (U6)"

  • "Ophelia (U7)"

  • "Bianca (U8)"

  • "Cressida (U9)"

  • "Desdemona (U10)"

  • "Juliet (U11)"

  • "Portia (U12)"

  • "Rosalind (U13)"

  • "Belinda (U14)"

  • "Puck (U15)"

  • "Perdita (U25)"

  • "Mab (U26)"

  • "Cupid (U27)"

Neptune:

  • "Neptune"

  • "Triton (N1)"

  • "Nereid (N2)"

  • "Naiad (N3)"

  • "Thalassa (N4)"

  • "Despina (N5)"

  • "Galatea (N6)"

  • "Larissa (N7)"

  • "Proteus (N8)"

  • "Hippocamp (N14)"

Pluto:

  • "Barycenter"

  • "Pluto"

  • "Charon (P1)"

  • "Nix (P2)"

  • "Hydra (P3)"

  • "Kerberos (P4)"

  • "Styx (P5)"

center_ansa (select, when center=”ansa”)

Ring to center on. Leading space from HTML formatting.

Mars:

  • "Phobos Ring"

  • "Deimos Ring"

Jupiter:

  • "Halo"

  • "Main Ring"

  • "Amalthea Ring"

  • "Thebe Ring"

Saturn:

  • "C Ring"

  • "B Ring"

  • "A Ring"

  • "F Ring"

  • "G Ring"

  • "E Ring core"

Uranus:

  • "6 Ring"

  • "5 Ring"

  • "4 Ring"

  • "Alpha Ring"

  • "Beta Ring"

  • "Eta Ring"

  • "Gamma Ring"

  • "Delta Ring"

  • "Lambda Ring"

  • "Epsilon Ring"

  • "Nu Ring"

  • "Mu Ring"

Neptune:

  • "Galle Ring"

  • "LeVerrier Ring"

  • "Arago Ring"

  • "Adams Ring"

Pluto:

  • "Styx"

  • "Nix"

  • "Kerberos"

  • "Hydra"

center_ew (select, when center=”ansa”)

Ansa direction.

Possible values:

  • "east"

  • "west"

center_ra (text, when center=”J2000”)

Right ascension for diagram center. Free-text numeric.

center_ra_type (select, when center=”J2000”)

RA unit. Forms use value="hours" and value="degrees" (no leading space). The backend strips leading and trailing whitespace before applying the parsing rule. After stripping, if the value is exactly degrees or hours, that is used (so " degrees" → degrees parses as degrees). A literal leading + (e.g. from URL-encoded space) is treated as hours. Otherwise the first character determines units: d/D → degrees (the center_ra_type first-character rule is applied to the stripped string).

center_dec (text, when center=”J2000”)

Declination in degrees for diagram center. Free-text numeric.

center_star (text, when center=”star”)

Star name for diagram center. Free text.

Viewpoint

viewpoint (radio or hidden)

Observer type.

Possible values:

  • "observatory"

  • "latlon"

When PREFIX is set (mission-specific forms), this is a hidden field with value "observatory".

observatory (select or hidden)

Observatory or spacecraft name.

When PREFIX is set, this is a hidden field with one of:

  • "Cassini"

  • "New Horizons"

  • "Juno"

  • "JUICE"

  • "Europa Clipper"

When PREFIX is empty (Earth-based forms), this is a select. The shared VIEWPOINT.shtml include is used only by the viewer for Jupiter, Saturn, Uranus, and Neptune. The ephemeris and tracker forms use the same include but with a different TOOL value, so the spacecraft block is not rendered—they show only Earth-based observatories. The Mars and Pluto viewer forms define their own viewpoint section (do not use VIEWPOINT.shtml) and have no spacecraft options except Pluto, which includes New Horizons.

Common options (all Earth-based forms):

  • "Earth's center" (form may send with leading space; normalized to this)

  • "HST"

  • "JWST"

  • "Apache Point Observatory (32.780361, -105.820417, 2674.)"

  • "Kitt Peak National Observatory (31.958833, -111.594694, 2058.4)"

  • "Lowell Observatory (35.097, -111.537, 2200.)"

  • "Mauna Kea Observatory (19.827, -155.472, 4215.)"

  • "McDonald Observatory (30.671500, -104.022611, 2076.)"

  • "Mt. Evans Observatory (39.587, -105.640, 4305.)"

  • "NMSU Observatory (32.27631, -106.746556, 0.)"

  • "Paranal Observatory/VLT (-24.625417, -70.402806, 2635.)"

  • "Yerkes Observatory (42.57, -88.557, 334.)"

Spacecraft as observatory options appear only in the Jupiter, Saturn, Uranus, and Neptune viewer forms (via VIEWPOINT.shtml with TOOL=viewer3): Jupiter has Voyager 1, Voyager 2, Galileo, Cassini, New Horizons, Juno, JUICE, Europa Clipper; Saturn has Voyager 1, Voyager 2, Cassini; Uranus and Neptune have Voyager 2. Mars viewer has no spacecraft. Pluto viewer uses its own viewpoint section and includes only "New Horizons" in addition to the common list.

latitude (text, when viewpoint=”latlon”)

Observer latitude in degrees. Free-text numeric.

longitude (text, when viewpoint=”latlon”)

Observer longitude in degrees. Free-text numeric.

lon_dir (select, when viewpoint=”latlon”)

Longitude direction.

Possible values:

  • "east"

  • "west"

altitude (text, when viewpoint=”latlon”)

Observer altitude in meters. Free-text numeric.

Moon Selection

moons (radio, single value)

Predefined moon group. The leading number is a group code used by the FORTRAN to select moons where moon_id <= group_code.

Mars (hidden field, not radio):

  • "402 Phobos, Deimos"

Jupiter:

  • "504 Galilean satellites (J1-J4)"

  • "505 Galilean satellites, Amalthea (J1-J5)"

  • "516 All inner moons (J1-J5,J14-J16)"

Saturn:

  • "609 Classical satellites (S1-S9)"

  • "618 Classicals, Voyager discoveries (S1-S18)"

  • "653 All inner moons (S1-S18,S32-S35,S49,S53)"

Uranus:

  • "705 Classical satellites (U1-U5)"

  • "715 Classicals, Voyager discoveries (U1-U15)"

  • "727 All inner moons (U1-U15,U25-U27)"

Neptune:

  • "802 Triton & Nereid"

  • "814 All inner moons (N1-N8,N14)"

Pluto:

  • "901 Charon (P1)"

  • "903 Charon, Nix, Hydra (P1-P3)"

  • "905 All moons (P1-P5)"

NAIF IDs included per group code:

  • 402: 401 (Phobos), 402 (Deimos)

  • 504: 501 (Io), 502 (Europa), 503 (Ganymede), 504 (Callisto)

  • 505: 501-505 (adds Amalthea)

  • 516: 501-505, 514 (Thebe), 515 (Adrastea), 516 (Metis)

  • 609: 601 (Mimas) through 609 (Phoebe)

  • 618: 601-618 (Mimas through Pan)

  • 653: 601-618, 632 (Methone), 633 (Pallene), 634 (Polydeuces), 635 (Daphnis), 649 (Anthe), 653 (Aegaeon)

  • 705: 701 (Ariel) through 705 (Miranda)

  • 715: 701-715 (Ariel through Puck)

  • 727: 701-715, 725 (Perdita), 726 (Mab), 727 (Cupid)

  • 802: 801 (Triton), 802 (Nereid)

  • 814: 801-808, 814 (Hippocamp)

  • 901: 901 (Charon)

  • 903: 901 (Charon), 902 (Nix), 903 (Hydra)

  • 905: 901-905 (Charon, Nix, Hydra, Kerberos, Styx)

Ring Selection

rings (radio, single value)

Comma-separated ring names or group descriptions.

Mars:

  • "None"

  • "Phobos, Deimos"

Jupiter:

  • "None"

  • "Main"

  • "Main & Gossamer"

Saturn:

  • "A,B,C"

  • "A,B,C,F"

  • "A,B,C,F,E"

  • "A,B,C,F,G,E"

Uranus:

  • "Alpha, Beta, Eta, Gamma, Delta, Epsilon"

  • "Nine major rings"

  • "All inner rings"

  • "All rings"

Neptune:

  • "LeVerrier, Adams"

  • "LeVerrier, Arago, Adams"

  • "Galle, LeVerrier, Arago, Adams"

Pluto:

  • "None"

  • "Charon"

  • "Charon, Nix, Hydra"

  • "Charon, Styx, Nix, Kerberos, Hydra"

  • "Nix, Hydra"

  • "Styx, Nix, Kerberos, Hydra"

Arc Model (Neptune only)

arcmodel (radio)

Neptune arc motion model.

Possible values:

  • "#1 (820.1194 deg/day)"

  • "#2 (820.1118 deg/day)"

  • "#3 (820.1121 deg/day)"

Background Objects

standard (checkbox)

Standard stars overlay.

Possible values:

  • "Yes" (when checked)

  • absent (when unchecked)

additional (checkbox)

Additional user-specified star.

Possible values:

  • "Yes" (when checked)

  • absent (when unchecked)

extra_ra (text)

Additional star right ascension. Free-text numeric.

extra_ra_type (select)

RA unit for additional star.

Possible values:

  • "hours"

  • "degrees"

extra_dec (text)

Additional star declination in degrees. Free-text numeric.

extra_name (text)

Additional star label. Free text.

other (checkbox, multi-valued)

Other bodies to mark on the diagram. Multiple values are joined with # by newcgi.pm.

All planets:

  • "Sun"

  • "Anti-Sun"

  • "Earth"

Jupiter (PREFIX empty):

  • "Voyager 1"

  • "Voyager 2"

  • "Galileo"

  • "Cassini"

  • "New Horizons"

  • "Juno"

  • "JUICE"

  • "Europa Clipper"

Jupiter (PREFIX=”JUICE/”):

  • "Europa Clipper"

Jupiter (PREFIX=”Europa Clipper/”):

  • "JUICE"

Saturn (PREFIX empty):

  • "Voyager 1"

  • "Voyager 2"

  • "Cassini"

Uranus (PREFIX empty):

  • "Voyager 2"

Neptune (PREFIX empty):

  • "Voyager 2"

Pluto:

  • "Barycenter"

  • "New Horizons" (PREFIX empty only)

Diagram Options

title (text)

Plot title. Free text, max 60 characters.

labels (select)

Moon and star label size.

Possible values:

  • "None"

  • "Small (6 points)"

  • "Medium (9 points)"

  • "Large (12 points)"

moonpts (text)

Moon enlargement in points. Free-text numeric. Default "0".

blank (radio, PREFIX empty only)

Blank disks mode.

Possible values:

  • "Yes"

  • "No"

opacity (select, Saturn only)

Ring plot type.

Possible values:

  • "Transparent"

  • "Semi-transparent (2x file size)"

  • "Opaque"

peris (select, Saturn and Uranus only)

Pericenter marker selection.

Saturn:

  • "None"

  • "F Ring"

Uranus:

  • "None"

  • "Epsilon Ring only"

  • "All rings"

peripts (text, Saturn and Uranus only)

Pericenter marker size in points. Free-text numeric. Default "4".

meridians (radio)

Highlight prime meridians.

Possible values:

  • "Yes"

  • "No"

arcpts (text, Neptune only)

Arc weight in points. Free-text numeric. Default "4".

Jupiter-Specific

torus (checkbox, Jupiter only)

Io torus overlay.

Possible values:

  • "Yes" (when checked)

  • absent (when unchecked)

torus_inc (text, Jupiter only)

Io torus inclination in degrees. Default "6.8".

torus_rad (text, Jupiter only)

Io torus radius in km. Default "422000".

Tracker Parameters

All tracker forms submit to tracker3_xxx.pl (now tracker3_xxx.sh).

Metadata

abbrev (hidden)

Identifies the planet and optional mission prefix.

Possible values:

  • "mar"

  • "jup"

  • "sat"

  • "ura"

  • "nep"

  • "plu"

  • "jupj"

  • "jupjc"

  • "jupec"

  • "satc"

  • "plunh"

Note: tracker3_jupc.shtml and tracker3_jupnh.shtml set ABBREV to "jup" (not "jupc" or "jupnh"), so the Cassini and New Horizons Jupiter trackers send the same abbrev as the plain Jupiter tracker; they differ only in PREFIX, which controls the viewpoint hidden fields.

version (hidden)

Form version string.

Possible values:

  • "3.0"

output (radio)

Output format.

Possible values:

  • "HTML"

  • "PDF"

  • "JPEG"

  • "PS"

  • "TAB"

submit (submit button)

Always "Submit". Ignored by the backend.

Ephemeris Selection

ephem (hidden)

SPICE kernel selection string.

Possible values:

  • "000 MAR097 + DE440" (Mars)

  • "000 JUP365 + DE440" (Jupiter, non-New-Horizons)

  • "000 JUP344 + JUP365 + DE440" (Jupiter, New Horizons)

  • "000 SAT415 + SAT441 + DE440" (Saturn)

  • "000 URA111 + URA115 + DE440" (Uranus)

  • "000 NEP095 + NEP097 + NEP101 + DE440" (Neptune)

  • "000 PLU058 + DE440" (Pluto)

Time Range

start (text)

Start time. Free-text datetime.

stop (text)

Stop time. Free-text datetime.

interval (text)

Time step size. Free-text numeric.

time_unit (select)

Time step unit.

Possible values:

  • "seconds"

  • "minutes"

  • "hours"

  • "days"

Viewpoint

viewpoint (radio or hidden)

Observer type.

Possible values:

  • "observatory"

  • "latlon"

When PREFIX is set (mission-specific forms), this is a hidden field with value "observatory".

observatory (select or hidden)

Observatory or spacecraft name.

When PREFIX is set, this is a hidden field with one of:

  • "Cassini"

  • "New Horizons"

  • "Juno"

  • "JUICE"

  • "Europa Clipper"

When PREFIX is empty (Earth-based forms), this is a select with:

  • "Earth's center" (form may send with leading space; normalized to this)

  • "HST"

  • "JWST"

  • "Apache Point Observatory (32.780361, -105.820417, 2674.)"

  • "Kitt Peak National Observatory (31.958833, -111.594694, 2058.4)"

  • "Lowell Observatory (35.097, -111.537, 2200.)"

  • "Mauna Kea Observatory (19.827, -155.472, 4215.)"

  • "McDonald Observatory (30.671500, -104.022611, 2076.)"

  • "Mt. Evans Observatory (39.587, -105.640, 4305.)"

  • "NMSU Observatory (32.27631, -106.746556, 0.)"

  • "Paranal Observatory/VLT (-24.625417, -70.402806, 2635.)"

  • "Yerkes Observatory (42.57, -88.557, 334.)"

The tracker form includes VIEWPOINT.shtml with TOOL=tracker3, so the spacecraft block in that include is not rendered. The tracker observatory select has no spacecraft options—only Earth-based observatories.

latitude (text, when viewpoint=”latlon”)

Observer latitude in degrees. Free-text numeric.

longitude (text, when viewpoint=”latlon”)

Observer longitude in degrees. Free-text numeric.

lon_dir (select, when viewpoint=”latlon”)

Longitude direction.

Possible values:

  • "east"

  • "west"

altitude (text, when viewpoint=”latlon”)

Observer altitude in meters. Free-text numeric.

Moon Selection

moons (checkbox, multi-valued)

Individual moon checkboxes. The leading three-digit number is the moon’s 1-based index within the planet system. Multiple values are joined with # by newcgi.pm.

Mars:

  • "001 Phobos (M1)"

  • "002 Deimos (M2)"

Jupiter:

  • "001 Io (J1)"

  • "002 Europa (J2)"

  • "003 Ganymede (J3)"

  • "004 Callisto (J4)"

  • "005 Amalthea (J5)"

  • "014 Thebe (J14)"

  • "015 Adrastea (J15)"

  • "016 Metis (J16)"

  • "006 Himalia (J6)" (New Horizons only)

  • "007 Elara (J7)" (New Horizons only)

Saturn:

  • "001 Mimas (S1)"

  • "002 Enceladus (S2)"

  • "003 Tethys (S3)"

  • "004 Dione (S4)"

  • "005 Rhea (S5)"

  • "006 Titan (S6)"

  • "007 Hyperion (S7)"

  • "008 Iapetus (S8)"

  • "009 Phoebe (S9)"

  • "010 Janus (S10)"

  • "011 Epimetheus (S11)"

  • "012 Helene (S12)"

  • "013 Telesto (S13)"

  • "014 Calypso (S14)"

  • "015 Atlas (S15)"

  • "016 Prometheus (S16)"

  • "017 Pandora (S17)"

  • "018 Pan (S18)"

  • "032 Methone (S32)"

  • "033 Pallene (S33)"

  • "034 Polydeuces (S34)"

  • "035 Daphnis (S35)"

  • "049 Anthe (S49)"

  • "053 Aegaeon (S53)"

Uranus:

  • "001 Ariel (U1)"

  • "002 Umbriel (U2)"

  • "003 Titania (U3)"

  • "004 Oberon (U4)"

  • "005 Miranda (U5)"

  • "006 Cordelia (U6)"

  • "007 Ophelia (U7)"

  • "008 Bianca (U8)"

  • "009 Cressida (U9)"

  • "010 Desdemona (U10)"

  • "011 Juliet (U11)"

  • "012 Portia (U12)"

  • "013 Rosalind (U13)"

  • "014 Belinda (U14)"

  • "015 Puck (U15)"

  • "025 Perdita (U25)"

  • "026 Mab (U26)"

  • "027 Cupid (U27)"

Neptune:

  • "001 Triton (N1)"

  • "002 Nereid (N2)"

  • "003 Naiad (N3)"

  • "004 Thalassa (N4)"

  • "005 Despina (N5)"

  • "006 Galatea (N6)"

  • "007 Larissa (N7)"

  • "008 Proteus (N8)"

  • "014 Hippocamp (N14)"

Pluto:

  • "001 Charon (P1)"

  • "005 Styx (P5)"

  • "002 Nix (P2)"

  • "004 Kerberos (P4)"

  • "003 Hydra (P3)"

Ring Selection

rings (checkbox, multi-valued)

Ring option checkboxes. The leading three-digit number is an internal code (not a NAIF ID). Multiple values are joined with # by newcgi.pm.

Jupiter:

  • "051 Main Ring"

  • "052 Gossamer Rings"

Saturn:

  • "061 Main Rings"

  • "062 G Ring"

  • "063 E Ring"

Uranus:

  • "071 Epsilon Ring"

Neptune:

  • "081 Adams Ring"

Mars and Pluto tracker forms do not include ring checkboxes (the TRACKER3_FORM.shtml ring conditional only covers Jupiter, Saturn, Uranus, and Neptune), so this ring selection section applies only to those four planets.

Plot Options

xrange (text)

Scale half-width. Free-text numeric.

xunit (select)

Scale unit.

Possible values (when PREFIX is empty):

  • "arcsec"

  • "Mars radii" (Mars)

  • "Jupiter radii" (Jupiter)

  • "Saturn radii" (Saturn)

  • "Uranus radii" (Uranus)

  • "Neptune radii" (Neptune)

  • "Pluto radii" (Pluto)

Possible values (when PREFIX is set):

  • "degrees"

  • "Jupiter radii" (Jupiter)

  • "Saturn radii" (Saturn)

  • "Uranus radii" (Uranus)

  • "Neptune radii" (Neptune)

  • "Pluto radii" (Pluto)

title (text)

Plot title. Free text, max 60 characters.

Ephemeris Generator Parameters

All ephemeris forms submit to ephem3_xxx.pl (now ephem3_xxx.sh).

Metadata

abbrev (hidden)

Identifies the planet and optional mission prefix.

Possible values:

  • "mar"

  • "jup"

  • "sat"

  • "ura"

  • "nep"

  • "plu"

  • "jupc"

  • "jupj"

  • "jupjc"

  • "jupnh"

  • "jupec"

  • "satc"

  • "plunh"

version (hidden)

Form version string.

Possible values:

  • "3.0"

output (radio)

Output format.

Possible values:

  • "HTML"

  • "TAB"

submit (submit button)

Always "Generate table". Ignored by the backend.

Ephemeris Selection

ephem (hidden)

SPICE kernel selection string.

Possible values:

  • "000 MAR097 + DE440" (Mars)

  • "000 JUP365 + DE440" (Jupiter, non-New-Horizons)

  • "000 JUP344 + JUP365 + DE440" (Jupiter, New Horizons)

  • "000 SAT415 + SAT441 + DE440" (Saturn)

  • "000 URA111 + URA115 + DE440" (Uranus)

  • "000 NEP095 + NEP097 + NEP101 + DE440" (Neptune)

  • "000 PLU058 + DE440" (Pluto)

Time Range

start (text)

Start time. Free-text datetime.

stop (text)

Stop time. Free-text datetime.

interval (text)

Time step size. Free-text numeric.

time_unit (select)

Time step unit.

Possible values:

  • "seconds"

  • "minutes"

  • "hours"

  • "days"

Viewpoint

viewpoint (radio or hidden)

Observer type.

Possible values:

  • "observatory"

  • "latlon"

When PREFIX is set (mission-specific forms), this is a hidden field with value "observatory".

observatory (select or hidden)

Observatory or spacecraft name.

When PREFIX is set, this is a hidden field with one of:

  • "Cassini"

  • "New Horizons"

  • "Juno"

  • "JUICE"

  • "Europa Clipper"

When PREFIX is empty (Earth-based forms), this is a select with:

  • "Earth's center" (form may send with leading space; normalized to this)

  • "HST"

  • "JWST"

  • "Apache Point Observatory (32.780361, -105.820417, 2674.)"

  • "Kitt Peak National Observatory (31.958833, -111.594694, 2058.4)"

  • "Lowell Observatory (35.097, -111.537, 2200.)"

  • "Mauna Kea Observatory (19.827, -155.472, 4215.)"

  • "McDonald Observatory (30.671500, -104.022611, 2076.)"

  • "Mt. Evans Observatory (39.587, -105.640, 4305.)"

  • "NMSU Observatory (32.27631, -106.746556, 0.)"

  • "Paranal Observatory/VLT (-24.625417, -70.402806, 2635.)"

  • "Yerkes Observatory (42.57, -88.557, 334.)"

The ephemeris form includes VIEWPOINT.shtml with TOOL=ephem3, so the spacecraft block in that include is not rendered. The ephemeris observatory select has no spacecraft options—only Earth-based observatories.

latitude (text, when viewpoint=”latlon”)

Observer latitude in degrees. Free-text numeric.

longitude (text, when viewpoint=”latlon”)

Observer longitude in degrees. Free-text numeric.

lon_dir (select, when viewpoint=”latlon”)

Longitude direction.

Possible values:

  • "east"

  • "west"

altitude (text, when viewpoint=”latlon”)

Observer altitude in meters. Free-text numeric.

General Columns

columns (checkbox, multi-valued)

Column selection checkboxes. The leading three-digit number is the column ID. Multiple values are joined with # by newcgi.pm.

All planets (PREFIX empty, Earth-based):

  • "001 Modified Julian Date"

  • "002 Year, Month, Day, Hour, Minute"

  • "003 Year, Month, Day, Hour, Minute, Second"

  • "004 Year, DOY, Hour, Minute"

  • "005 Year, DOY, Hour, Minute, Second"

  • "006 Observer-[Planet] distance"

  • "007 Sun-[Planet] distance"

  • "008 [Planet] phase angle"

  • "009 Ring plane opening angle to observer"

  • "010 Ring plane opening angle to Sun"

  • "011 Sub-observer inertial longitude"

  • "012 Sub-solar inertial longitude"

  • "013 Sub-observer latitude & rotating longitude"

  • "014 Sub-solar latitude & rotating longitude"

  • "015 [Planet] RA & Dec"

  • "018 [Planet] projected equatorial radius" (arcsec)

  • "020 Lunar phase angle"

  • "021 Sun-[Planet] sky separation angle"

  • "022 Lunar-[Planet] sky separation angle"

All planets (PREFIX set, spacecraft-based):

  • "001 Modified Julian Date"

  • "002 Year, Month, Day, Hour, Minute"

  • "003 Year, Month, Day, Hour, Minute, Second"

  • "004 Year, DOY, Hour, Minute"

  • "005 Year, DOY, Hour, Minute, Second"

  • "006 Observer-[Planet] distance"

  • "007 Sun-[Planet] distance"

  • "008 [Planet] phase angle"

  • "009 Ring plane opening angle to observer"

  • "010 Ring plane opening angle to Sun"

  • "011 Sub-observer inertial longitude"

  • "012 Sub-solar inertial longitude"

  • "013 Sub-observer latitude & rotating longitude"

  • "014 Sub-solar latitude & rotating longitude"

  • "015 [Planet] RA & Dec"

  • "016 Earth RA & Dec"

  • "017 Sun RA & Dec"

  • "019 [Planet] projected equatorial radius" (deg)

Note: [Planet] is replaced by the actual planet name (Mars, Jupiter, Saturn, Uranus, Neptune, Pluto) in each form.

Moon Columns

mooncols (checkbox, multi-valued)

Moon column selection checkboxes. The leading three-digit number is the column ID. Multiple values are joined with # by newcgi.pm.

Earth-based (PREFIX empty):

  • "003 Sub-observer latitude & rotating longitude"

  • "004 Sub-solar latitude & rotating longitude"

  • "005 RA & Dec"

  • "006 Offset RA & Dec from the moon (arcsec)"

  • "008 Orbital longitude relative to observer"

  • "009 Orbit plane opening angle to observer"

Spacecraft-based (PREFIX set):

  • "001 Observer-moon distance"

  • "002 Moon phase angle"

  • "003 Sub-observer latitude & rotating longitude"

  • "004 Sub-solar latitude & rotating longitude"

  • "005 RA & Dec"

  • "007 Offset RA & Dec from the moon (deg)"

  • "008 Orbital longitude relative to observer"

  • "009 Orbit plane opening angle to observer"

Moon Selection

moons (checkbox, multi-valued)

Individual moon checkboxes. Identical to the Tracker moon selection (see Tracker Parameters > Moon Selection above for the complete list per planet).