USSR
Stamp from Souvenir sheet.
| Country: | USSR |
| Type: | Postage stamps |
| Series: | Soviet Phobos probe approaches Mars |
| Nominal: | 50 k |
| Year: | 1989 |
| Size: | 52 x 37 mm |
| Perforation: | frame 11½ x 12 |
| Mintage: | 1,300,000 |