Mars, Phobos & Deimos, Brisbane 15th May 2016

[Dennis]

More with hope than confidence, I set up on Sunday night, 15th May to see if I could record the two moons of Mars; Phobos and Deimos.

I expected Deimos to be fairly straightforward, lying some 60 arc secs from Mars but, Phobos would only be 24 arc sec distant, bathed in the glare of the Martian disc.

The seeing was very good and when the results came in, Deimos was unmistakable and I had a few grains of light as a promising candidate for Phobos.

After much histogram stretching in ImagesPlus 6 and AstroArt 6, I was able to get everything to “pop out” in one aligned/stacked frame, including 4 field stars.

Mewlon 180 F12, TeleVue x2 PowerMate, Atik 414EX CCD camera, 20x4 sec exposures, 10:08pm AEST.

For the disc of Mars, I used a ZWO ASI224MC CMOS camera and overlaid the (re-sized) image over the grossly over-exposed Martian disc.

Cheers

Dennis

[John Hothersall]

That's a great effort Dennis especially with those diff spikes. I thought of doing this myself, but Phobos gets a bit too close sometimes and it is a bit of a challenge. Good seeing is a must.

Very inspiring!

John.

[Camelopardalis (Dunk)]

+1 very nice work Dennis

[Atmos (Colin)]

Fantastic job Dennis!

[Dennis]

Thanks John, Dunk and Colin, I appreciate your comments.

The Mewlon 3 vane spider produces 6 spikes and as fate would have it, when chasing Miranda (Uranus) and these two small moons of Mars, they have invariably appeared immersed in one of the diffraction spikes.

I guess a set of tube rings might fix this, allowing me to orient the tube differently for these interesting targets.

For this session, SkyTools 3 Pro provided the following information:

Mars, Diameter: 6794.0 km
R.A.: 16h06m56.4s Dec.: -21°42'32" (2000) in Scorpius
Magnitude: -1.90
Size: 18"

Satellites:
Name Mag PA° Sep"
Phobos 11.3 128.9 24.5
Deimos 12.4 125.1 60.3

Earth Distance: 0.5 AU
Sun Distance: 1.5 AU
Phase: 1.00
Phase Angle: 6.0°
Position Angle of axis: 36.3°
Central Longitude: 56.9°
Central Latitude: 9.1°

Cheers

Dennis

[Derek Klepp]

A good bit of science Dennis thanks.

[andyc (Andy)]

Great project, and well done on the result, nice one!

[Merlin66 (Ken)]

Good result, well done.
An acculting bar - narrow aluminum strip may help.

[Dennis]

Thanks Derek, Andy and Ken, I appreciate your comments.

@Ken – thanks for that tip, I’ll look into it.

Cheers

Dennis

[astronobob (Bob)]

Very Cool captures Dennis, thems is tiny moons, any idea of their magnitudes ? just a thought as guess their visual mags would change depending on how close they are to mars from this perspective in relation to us ?
just a thought.
Mars detail is quite solid at this wide view also

[Dennis]

Originally Posted by astronobob

Very Cool captures Dennis, thems is tiny moons, any idea of their magnitudes ? just a thought as guess their visual mags would change depending on how close they are to mars from this perspective in relation to us ?
just a thought.
Mars detail is quite solid at this wide view also

Hi Bob

The best time to grab an image of Phobos is when it is at either Eastern or Western Elongation, as it is then furthest away from the disc of Mars as viewed from the Earth.

On 15th May when I managed to grab this image, SkyTools 3 Pro shows the following magnitudes of Mars, Phobos & Deimos:

Mars
R.A.: 16h06m56.4s Dec.: -21°42'32" (2000) in Scorpius
Magnitude: -1.90
Size: 18"

Satellites:
Name Mag PA° Sep"
Phobos 11.3 128.9 24.5
Deimos 12.4 125.1 60.3

Cheers

Dennis

[multiweb (Marc)]

Some great detective work here again Dennis. Very cool shots and overlays.

[steradian]

Good work Dennis. I was wondering if anyone has been looking at Mars's potatoes.

[Dennis]

Originally Posted by multiweb

Some great detective work here again Dennis. Very cool shots and overlays.

Originally Posted by steradian

Good work Dennis. I was wondering if anyone has been looking at Mars's potatoes.

Thank you Marc and steradian, I appreciate your comments.

Cheers

Dennis

[astronobob (Bob)]

Originally Posted by Dennis

Hi Bob

The best time to grab an image of Phobos is when it is at either Eastern or Western Elongation, as it is then furthest away from the disc of Mars as viewed from the Earth.

On 15th May when I managed to grab this image, SkyTools 3 Pro shows the following magnitudes of Mars, Phobos & Deimos:

Mars
R.A.: 16h06m56.4s Dec.: -21°42'32" (2000) in Scorpius
Magnitude: -1.90
Size: 18"

Satellites:
Name Mag PA° Sep"
Phobos 11.3 128.9 24.5
Deimos 12.4 125.1 60.3

Cheers

Dennis

Keool, thanx for that Dennis