Radio Astronomy, Earth Exploration- Satellite (passive) and Space Research (passive) radio services have a only small fraction of the radio spectrum allocated to them. Most of that fraction of spectrum is shared with other radio services which emit power levels many orders of magnitude higher than the sensitivity of the receivers of the passive services, especially radio astronomy.
Natural emissions occur throughout the radio spectrum. Investigating the abundance and distribution of molecules in dark interstellar clouds requires observations at many frequencies throughout the spectrum. With only a limited amount of regulatory protection, astronomy research is dependent on the awareness and ecologically sound practices of other spectrum users. Like clean water and clean air, a conscientously used spectrum is a source of new knowledge for Mankind and a legacy for the future.
A personal view of the world frequency regulatory process at work by Tom Kuiper shows how challenging it is to keep radio astronomy a viable activity.
| Frequency Band | Canberra DSCC | Goldstone DSCC | Madrid DSCC | |||
|---|---|---|---|---|---|---|
| Stations: | 34 | 43 | 13 | 14 | 54 | 63 |
| 1610-1723 MHz | oper | oper | oper | |||
| near 6 GHz | under constr. | |||||
| 7.8-8.7 GHz | oper | |||||
| 13-18.3 GHz | oper | |||||
| 18-26 GHz | oper | oper | oper | oper | ||
| 31-34 GHz | oper | exper | ||||
| 40-50 GHz | oper | |||||
| 70-115 GHz | desired | oper | desired | |||
| desired | This capability is desired by the Space VLBI community to support future missions such as ARISE. |
| exper | experimental: equipment is installed and removed as needed for tests, with a future capability in mind |
| oper | operational |