C/2018 N1 NEOWISE
 

Closest to Earth 2018 July 27 at 0.30AU
Closest to Sun 2018 August 1 at 1.30AU
Maximum Magnitude 8 in July 2018
Period ~6000 years

New comet C/2018 N1 NEOWISE was discovered by the infrared NEOWISE spacecraft on 2018 July 2, estimated at about magnitude 16 with 1.5' coma
I visually observed the comet on 2018 July 9.82 UT and it appeared much brighter than expected.
m1= 11.2:, Dia=5, DC=2...25x100mm B [Michael Mattiazzo, Swan Hill, Vic, Australia]
[First visual observation. Very diffuse coma that enhances slightly using a Swan band filter]

The comet brightened rapidly and reached magnitude 8 in late July as it sped past Earth at 0.30AU on July 27.
It is in a retrograde orbit, moving in a direction opposite the planets.
Perihelion occurred a few days later on August 1, at 1.30AU, hence it was an exceptionally favourable apparition.
Southern hemisphere observers were favoured as the comet was well situated in evening skies, rapidly traversing through the constellations of
Cetus, Aquarius, Sculptor, Pisces Austrinus, Microscopium, Sagittarius, Scorpius/Ophiuchus and Libra during July and August.

Below C/2018 N1 NEOWISE (lower left) on 2018 August 6.
Rho Oph cloud complex at centre. Antares at lower right. Globular cluster M4 at upper right.
Comet was estimated at magnitude 9.2 through 25x100mm binoculars

Below C/2018 N1 NEOWISE on 2018 July 18
Visually the comet appeared mag 8.8 using my 25x100mm binoculars with a big coma 10' across. (but very diffuse).

 

C/2018 N1 NEOWISE
2018 July 16.81 UT; m1= 9.7:, Dia=8, DC=2...25x100mm B [Michael Mattiazzo, Swan Hill, Vic, Australia]
[Coma is very large but very diffuse. Difficult to observe despite its brightness]


New Comet NEOWISE at top with planetary nebula NGC 246 in Cetus below on 2018 July 9.