#referencefile http://www.virtualastronomy.org/AVM_Version1.1May312008.pdf
#description The list of AVM keywords.  For further information, see the
#description specification at http://www.virtualastronomy.org, in particular the
#description reference document http://www.virtualastronomy.org/AVM_Version1.1May312008.pdf
1. Planet
1.1. [Type]
1.1.1. Terrestrial
1.1.2. Gas Giant
1.2.  [Feature]
1.2.1. Surface
1.2.1.1. Mountain
1.2.1.2. Canyon
1.2.1.3. Volcanic
1.2.1.4. Impact
1.2.1.5. Erosion
1.2.1.6. Liquid
1.2.1.7. Ice
1.2.2. Atmosphere
1.2.2.1. Cloud
1.2.2.2. Storm
1.2.2.3. Belt
1.2.2.4. Aurora
1.3. [Special Cases]
1.3.1. Transiting
1.3.2. Hot Jupiter
1.3.3. Pulsar planet
1.4. Satellite
1.4.1. [Feature]
1.4.1.1. Surface
1.4.1.1.1. Mountain
1.4.1.1.2. Canyon
1.4.1.1.3. Volcanic
1.4.1.1.4. Impact
1.4.1.1.5. Erosion
1.4.1.1.6. Liquid
1.4.1.1.7. Ice
1.4.1.2. Atmosphere
1.5. Ring
2. Interplanetary Body
2.1. Dwarf planet
2.2. Comet
2.2.1. Nucleus
2.2.2. Coma
2.2.3. Tail
2.2.3.1. Dust
2.2.3.2. Gas
2.3. Asteroid
2.4. Meteoroid
3. Star
3.1. [Evolutionary Stage]
3.1.1. Protostar
3.1.2. Young Stellar Object
3.1.3. Main Sequence
3.1.4. Red Giant
3.1.5. Red Supergiant
3.1.6. Blue Supergiant
3.1.7. White Dwarf
3.1.8. Supernova
3.1.9. Neutron Star
3.1.9.1. Pulsar
3.1.9.2. Magnetar
3.1.10. Black Hole
3.2. [Type]
3.2.1. Variable
3.2.1.1. Pulsating
3.2.1.2. Irregular
3.2.1.3. Eclipsing
3.2.1.4. Flare Star
3.2.1.5. Nova
3.2.1.6. X-Ray Binary (Star)
3.2.2. Carbon
3.2.3. Brown Dwarf
3.2.4. Wolf-Rayet
3.2.5. Blue Straggler
3.2.6. Exotic
3.2.6.1. X-Ray Binary
3.3.  [Spectral Type]
3.3.1. O
3.3.2. B
3.3.3. A
3.3.4. F
3.3.5. G
3.3.6. K
3.3.7. M
3.3.8. L
3.3.9. T
3.4. [Population]
3.4.1. I
3.4.2. II
3.4.3. III
3.5.  [Feature]
3.5.1. Photosphere
3.5.1.1. Granulation
3.5.1.2. Sunspot
3.5.2. Chromosphere
3.5.2.1. Flare
3.5.2.2. Facula
3.5.3. Corona
3.5.3.1. Prominence
3.6. [Grouping]
3.6.1. Binary
3.6.2. Triple
3.6.3. Multiple
3.6.4. Cluster
3.6.4.1. Open
3.6.4.2. Globular
3.7. Circumstellar Material
3.7.1. Planetary System
3.7.2. Disk
3.7.2.1. Protoplanetary
3.7.2.2. Accretion
3.7.2.3. Debris
3.7.3. Outflow
3.7.3.1. Solar Wind
3.7.3.2. Coronal Mass Ejection
4. Nebula
4.1. [Type]
4.1.1. Interstellar Medium
4.1.2. Star Formation
4.1.3. Planetary
4.1.4. Supernova Remnant
4.1.5. Jet
4.2.  [Appearance]
4.2.1. Emission
4.2.1.1. H II Region
4.2.2. Reflection
4.2.2.1. Light Echo
4.2.3. Dark
4.2.3.1. Molecular Cloud
4.2.3.2. Bok Globule
4.2.3.3. Proplyd
5. Galaxy
5.1. [Type]
5.1.1. Spiral
5.1.2. Barred
5.1.3. Lenticular
5.1.4. Elliptical
5.1.5. Ring
5.1.6. Irregular
5.1.7. Interacting
5.1.8. Gravitationally Lensed
5.2. [Size]
5.2.1. Giant
5.2.2. Dwarf
5.3. [Activity]
5.3.1. Normal
5.3.2. AGN
5.3.2.1. Quasar
5.3.2.2. Seyfert
5.3.2.3. Blazar
5.3.2.4. Liner
5.3.3. Starburst
5.3.4. Ultraluminous
5.4. [Component]
5.4.1. Bulge
5.4.2. Bar
5.4.3. Disk
5.4.4. Halo
5.4.5. Ring
5.4.6. Central Black Hole
5.4.7. Spiral Arm
5.4.8. Dust Lane
5.4.9. Center/Core
5.5.  [Grouping]
5.5.1. Pair
5.5.2. Multiple
5.5.3. Cluster
5.5.4. Supercluster
6. Cosmology
6.1. [Morphology]
6.1.1. Deep Field
6.1.2. Large-Scale Structure
6.1.3. Cosmic Background
6.2.  [Phenomenon]
6.2.1. Lensing
6.2.2. Gamma Ray Burst
6.2.3. Dark Matter
7. Sky Phenomenon
7.1. Night Sky
7.1.1. Constellation
7.1.2. Asterism
7.1.3. Milky Way
7.1.4. Trail
7.1.4.1. Meteor
7.1.4.2. Star
7.1.4.3. Satellite
7.1.5. Zodiacal Light
7.1.5.1. Gegenschein
7.1.6. Night glow
7.2. Eclipse
7.2.1. Solar
7.2.1.1. Total
7.2.1.2. Partial
7.2.1.3. Annular
7.2.2. Lunar
7.2.2.1. Total
7.2.2.2. Partial
7.2.2.3. Penumbral
7.2.3. Occultation
7.2.4. Transit
7.3. Light Phenomenon
7.3.1. Sunrise-Sunset
7.3.1.1. Green flash
7.3.1.2. Refractive Distortion
7.3.1.3. Sun Pillar
7.3.2. Cloud
7.3.2.1. Iridescent
7.3.2.2. Noctilucent
7.3.2.3. Nacreous
7.3.2.4. Corona
7.3.2.5. Glory
7.3.3. Rainbow
7.3.3.1. Moonbow
7.3.3.2. Fogbow
7.3.4. Halo
7.3.4.1. Circle
7.3.4.2. Parhelia
7.3.4.3. Arc
7.3.5. Ray-Shadow
7.3.5.1. Crepuscular ray
7.3.5.2. Anti-crepuscular ray
7.3.5.3. Earth shadow
7.3.6. Lightning
7.3.7. Aurora
8. Technology
8.1. Observatory
8.1.1. Facility
8.1.2. Telescope
8.1.3. Instrument
8.1.4. Detector
8.2. Spacecraft
8.2.1. Orbiter
8.2.2. Probe
8.2.3. Lander
8.2.4. Manned
8.2.5. Launch Vehicle
9. People
9.1. Scientist
9.2. Astronaut
9.3. Other/General