AP 23

Asteroid (51) Nemausa

3031afc

Discovered by Laurent in 1858; mag 9.9, in Sextans; diameter 85 ml, Earth distance 115m miles. With (a) mag 6.6 HIP 51538. Feb 21 2018, 0004 UT; 4 days before opposition. [31st observed asteroid]

Venus, Mercury, Moon Gathering

venumrc3070

1916 UT, Mar 8 2018 – Venus; mag -3.4, distance 155m miles, and Mercury; mag -0.8, distance 100m miles. Separation 2.7°. Conjunction occurred on March 5th. Below – two images of the 2 day 7 hr Moon 10° from Venus, Mar 19 2018, 1942 and 1959 UT. Mercury marked ‘M’.

vnmry 3182

vyrtgq 3234

Messier Lunar Craters

messier a 190418

A unique feature on the Moon, Messier (right) and Messier A were gouged out by a projectile following a very low-angle trajectory, resulting in elongated craters averaging 10 miles in diameter, and scattering comet-like debris 90 miles across Mare Fecunditatis. One of the Moon’s less ancient features at ~1 billion years. Seen here at 2128 IST, Apr 19 2018; Moon 3 days 19 hours.

Exquisite Rainbow

refraction reflection dark band

The consequence of light striking water; being first refracted as it enters the water droplet, then reflected as it strikes the rear of the droplet before refracting once more as it exits. The colours are separated and reversed, with the long wavelength red appearing on the outside. Note also Alexander’s Dark Band outside the primary bow, first described by the Greek Alexander of Aphrodisias more than 1800 years ago, and explained as an absence of scattered light between the primary and secondary bow. Apr 25 2018, 1908 IST.

V392 Per Outburst

vper 392 ctlys

Rare incidence of a dwarf nova undergoing a classical nova eruption. Normally ~15th magnitude, V392 Per rocketed to mag 6.2 on Apr 29 2018; seen here at est mag 6.3 at 0102 IST, Apr 30. With mag 5.7 HIP 21823 and mag 6.7 HIP 22041 in Perseus. These events in the nova cycle are expected to recur on timescales of 10,000 to 1 million years. [5th observed Nova]

ISS Solar Transit

72Znje

As predicted, at 122737 IST on Jun 26 2018, the International Space Station with six crew on board transits the Sun in just over half a second. Distance 300 miles, speed 17,200 mph. The Station is seen to enter at the ~2 o’c position and exit at the ~7 o’c. Above, actual speed; below, half speed.

IK45Vr

Mars Close Approach

Mars looms from Finbarr C on Vimeo.

Jul 31 2018; at 35.8 million miles, Mars’ closest proximity to Earth since 2003 and until 2035. Magnitude -2.8, declination -26°, diameter 24″. 4 days past opposition. A global dust storm has shrouded the planet’s features during this apparition.

C/2017 S3 – Comet PanStarrs

panst s3 17 cecam 46

Three magnitudes brighter following an outburst at the end of June, the latest comet from the PanStarrs factory is seen here in Camelopardalis at est mag 9.5 on Jul 6 2018, 0214 IST. Earth distance 130m miles. The comet apparently disintegrated before perihelion in August. With mag 4.6 CE Cam (a). [23rd observed comet]

Summer 2018 Planetary Parade

planetary parade

Nova Scuti 2018

novasct 110718

Jul 11 2018, 0048 IST; est mag 11.7. Discovered on Jun 29, max mag 10.6. Located 0.6° SW of Nova Sct 2017, still visible at est mag 12.8 (marked x). With (a) gamma Sct. [6th observed Nova]

CHAPTER XXIV