501.

The Moon at aphelion The Moon recedes to its orbit's furthest point from the Sun, which happens each month around the time of full moon. Thu, 26 Jul 2018 at 15:41 EDT (2,165 days ago) in Sagittarius

502.

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. Fri, 27 Jul 2018 at 01:06 EDT (2,164 days ago) in Capricornus

503.

The Moon at apogee The Moon recedes to its orbit's furthest point from the Earth, making it appear fractionally smaller than at other times of the month. Fri, 27 Jul 2018 at 01:43 EDT (2,164 days ago) in Sagittarius

504.

Close approach of the Moon and Mars The Moon and Mars pass close to each other. Fri, 27 Jul 2018 at 15:57 EDT (2,164 days ago) in Capricornus

505.

Full Moon The Moon reaches full phase and is visible for much of the night. Fri, 27 Jul 2018 at 16:20 EDT (2,164 days ago) in Capricornus

506.

Total lunar eclipse There will be an eclipse of the Moon, visible from Antarctica, Asia, Africa, south-western Russia, Europe and Australia. Fri, 27 Jul 2018 at 16:22 EDT (2,164 days ago) in Capricornus

507.

Conjunction of the Moon and Mars The Moon and Mars share the same right ascension, at a separation of 6°43'. Fri, 27 Jul 2018 at 18:03 EDT (2,164 days ago) in Capricornus

508.

Piscis Austrinid meteor shower 2018 The Piscis Austrinid meteor shower reaches its peak. Sat, 28 Jul 2018 (2,162 days ago) in Piscis Austrinus

509.

Southern δ-Aquariid meteor shower 2018 The Southern δ-Aquariid meteor shower reaches its peak. Mon, 30 Jul 2018 (2,161 days ago) in Aquarius

510.

α-Capricornid meteor shower 2018 The α-Capricornid meteor shower reaches its peak. Mon, 30 Jul 2018 (2,161 days ago) in Capricornus

511.

Mars at perigee Mars reaches its closest point to the Earth – marking the best time to observe it in 1970. Tue, 31 Jul 2018 at 03:44 EDT (2,160 days ago) in Capricornus

512.

Supernova SN2018eqq discovered A new supernova has been discovered in UGC 2536. Thu, 02 Aug 2018 (2,157 days ago)

513.

Moon at Last Quarter The Moon reaches last quarter phase – rising in the east at around midnight and appearing high in the sky by sunrise. Sat, 04 Aug 2018 at 14:18 EDT (2,156 days ago) in Cetus

514.

Close approach of the Moon and Collinder 50 The Moon and Collinder 50 pass close to each other. Mon, 06 Aug 2018 at 10:54 EDT (2,154 days ago) in Taurus

515.

Lunar occultation of Aldebaran The Moon will pass in front of Aldebaran (Alpha Tauri), creating a lunar occultation visible from Russia, Mongolia and China. Mon, 06 Aug 2018 at 14:39 EDT (2,154 days ago) in Taurus

516.

Uranus enters retrograde motion Uranus reverses its direction of motion across the sky. Tue, 07 Aug 2018 at 11:57 EDT (2,153 days ago) in Aries

517.

Mercury at inferior solar conjunction Mercury passes around the near side of the Sun. Wed, 08 Aug 2018 at 22:01 EDT (2,152 days ago) in Cancer

518.

The Moon at perigee The Moon makes its monthly closest approach to the Earth, making it appear fractionally larger than at other times of the month. Fri, 10 Aug 2018 at 14:06 EDT (2,150 days ago) in Cancer

519.

Partial solar eclipse There will be an eclipse of the Sun, visible from Russia, Eastern Asia, Greenland, eastern Canada, Kazakhstan and Northern Europe. Sat, 11 Aug 2018 at 05:46 EDT (2,149 days ago) in Leo

520.

New Moon The Moon disappears into the Sun's glare for a few days. Sat, 11 Aug 2018 at 05:58 EDT (2,149 days ago) in Leo