The Deepsky: Logs

The Deepsky Lists Logs Deepsky reports Top-100 Binocular objects

Logs

In this section you will find some entries from my deepsky log. It will be updated regularly. To view a particular log just go to the logs list.

Most of the data in the logs will be clear to other observers. There are however three registered data that require some explanation; the seeing, transparency and the sky darkness. I got these scales from Auke Slotegraaf from South Africa. Auke told me that he did not compose these scales himself. As far as he can recall an amateur astronomer by the name of Thompson made them. They were once published in an astronomy magazine. If anyone can help with this puzzle, please do!

Anyway, I find these Thompson scales very useful. Of course you can use other scales, like the Pickering scale for seeing conditions and the Bortle scale for sky darkness


My logs


Common Id

Constellation

Other Id's

Object Type

11 Beta Monoceros

Monoceros

Multiple Star

Jaws

Virgo

Harrington's Star 21

Asterism

M35

Gemini

NGC 2168

Open Cluster

M44

Cancer

NGC 2632, Praesepe, beehive

Open Cluster

M45

Taurus

Pleiaedes, Seven Sisters

Open Cluster

M47

Puppis

NGC 2422

Open Cluster

NGC 2169

Orion

Collinder 38

Open Cluster

NGC 2301

Monoceros

Open Cluster

NGC 7662

Andromeda

The blue snowball

Planetary Nebula

Pakan's 3

Monoceros

Harrington's Star 18

Asterism

Stargate

Corvus

Harrington's Star 20, delta winged starship

Asterism


The Seeing

01

The atmosphere is so steady that even stars close to the horizon appear to twinkle only occasionally. Excellent high-magnification views may be obtained of the planets and close double stars

02

The atmosphere is very steady with occasional disturbance of high-magnification images

03

03 The steadiness is good, but with regular air turbulence noticeable

04

There is a general loss of fine detail at high magnification

05

Twinkling stars are quite apparent, but the twinkling is not rapid. Images are blurred at medium powers

06

Fine detail is lost at medium power

07

Star images show rapid twinkling. They appear disk-like

08

Fuzzy images are detected at low power

09

Stars appear blurry and appear to change brightness very quickly

10

Atmosphere is boiling. There is a complete loss of detail


Transparency

01

Use 01 for the clearest possible sky. The atmosphere is perfectly transparent, only a slight amount of haze on the horizon

02

The sky is very clear but not perfectly transparent

03

Haze is noticeable towards the horizon, but the overhead sky is perfectly transparent

04

Very slight haze is noticeable overhead near bright objects

05

Haze appears overhead, but faint stars are visible

06

Obvious haze or thin clouds lie overhead

07

The faintest stars typically visible from the site are not visible

08

Smoke, haze or fog limits visibility significantly and creates glare around objects

09

At the zenith, absorption limits visibility by one magnitude

10

At the zenith, absorption limits visibility by two magnitudes or more


Sky Darkness

01

There is a total absence of moonlight and artificial lighting in the sky with good seeing and transparency

02

Very slight brightening of the sky, like that caused by zodiacal light

03

Three-day old moon or slight light pollution, but 6th magnitude stars are visible overhead

04

Faintest portions of milky-way barely visible

05

Overhead appears fairly dark but sky is fairly bright around horizon

06

Only the brightest portions of the milky-way are visible

07

General illumination of the entire sky, equal to seven-day old moon. Faintest stars visible are magnitude 5.5

08

Sky is bright, similar to three quart moon

09

Sky is very bright, faintest stars visible are magnitude 4.5

10

Illumination is equivalent to, or greater than, the full moon





Copyright © 2003 www.backyard-astro.com