501.

Neptune ends retrograde motion Neptune returns to its usual eastward motion after opposition. Wed, 13 Oct 1999 at 21:34 EDT (9,013 days ago) in Capricornus

502.

Saturn enters retrograde motion Saturn reverses its direction of motion across the sky. Sun, 29 Aug 1999 at 21:51 EDT (9,058 days ago) in Aries

503.

Jupiter enters retrograde motion Jupiter reverses its direction of motion across the sky. Tue, 24 Aug 1999 at 22:38 EDT (9,063 days ago) in Aries

504.

Uranus at opposition Uranus lies in the opposite direction to the Sun in the sky, making it optimally positioned to be observable for much of the night. Sat, 07 Aug 1999 at 14:29 EDT (9,080 days ago) in Capricornus

505.

Neptune at opposition Neptune lies in the opposite direction to the Sun in the sky, making it optimally positioned to be observable for much of the night. Mon, 26 Jul 1999 at 05:23 EDT (9,092 days ago) in Capricornus

506.

Mars ends retrograde motion Mars returns to its usual eastward motion after opposition. Fri, 04 Jun 1999 at 02:11 EDT (9,144 days ago) in Virgo

507.

Uranus enters retrograde motion Uranus reverses its direction of motion across the sky. Fri, 21 May 1999 at 18:31 EDT (9,158 days ago) in Capricornus

508.

Jupiter at perihelion Jupiter passes its orbit's closest point to the Sun. Wed, 19 May 1999 at 15:30 EDT (9,160 days ago) in Pisces

509.

Neptune enters retrograde motion Neptune reverses its direction of motion across the sky. Thu, 06 May 1999 at 20:21 EDT (9,173 days ago) in Capricornus

510.

Mars at perigee Mars reaches its closest point to the Earth – marking the best time to observe it in 1970. Sat, 01 May 1999 at 13:21 EDT (9,178 days ago) in Virgo

511.

Saturn at solar conjunction Saturn is unobservable as it passes around the far side of the Sun – marking the end of one apparition and the beginning of the next. Tue, 27 Apr 1999 at 06:54 EDT (9,182 days ago) in Aries

512.

Mars at opposition Mars lies in the opposite direction to the Sun in the sky, making it closer, brighter and larger than at other times. It is also optimally positioned to be observable for much of the night. Sat, 24 Apr 1999 at 13:31 EDT (9,185 days ago) in Virgo

513.

Jupiter at apogee Jupiter reaches its furthest point from the Earth, as it passes around the far side of the Sun. Fri, 02 Apr 1999 at 08:02 EDT (9,207 days ago) in Pisces

514.

Jupiter at solar conjunction Jupiter is unobservable as it passes around the far side of the Sun – marking the end of one apparition and the beginning of the next. Thu, 01 Apr 1999 at 00:59 EDT (9,208 days ago) in Pisces

515.

Mars enters retrograde motion Mars reverses its direction of motion across the sky. Thu, 18 Mar 1999 at 08:45 EDT (9,222 days ago) in Libra

516.

Uranus at solar conjunction Uranus is unobservable as it passes around the far side of the Sun – marking the end of one apparition and the beginning of the next. Mon, 01 Feb 1999 at 20:49 EDT (9,267 days ago) in Capricornus

517.

Neptune at solar conjunction Neptune is unobservable as it passes around the far side of the Sun – marking the end of one apparition and the beginning of the next. Fri, 22 Jan 1999 at 03:13 EDT (9,277 days ago) in Capricornus

518.

Saturn ends retrograde motion Saturn returns to its usual eastward motion after opposition. Tue, 29 Dec 1998 at 10:56 EDT (9,301 days ago) in Pisces

519.

Mars at aphelion Mars passes the furthest point along its orbit from the Sun. Wed, 16 Dec 1998 at 15:32 EDT (9,314 days ago) in Virgo

520.

Jupiter ends retrograde motion Jupiter returns to its usual eastward motion after opposition. Fri, 13 Nov 1998 at 07:52 EDT (9,347 days ago) in Aquarius