Dennis
07-10-2020, 11:46 AM
On Tuesday, October 6th 2020, Mars had a close encounter with Earth, albeit some 62 million km (38.6 million miles) from my back garden in Brisbane.
On that evening, Fear and Dread also stalked the night skies in Brisbane, namely the 2 small moons of Mars, Phobos (Fear) and Deimos (Dread). Both moons were discovered in 1877 by Asaph Hall. Ninety-four years later, NASA's Mariner 9 spacecraft got a much better look at the two moons from its orbit around Mars.
I managed to record images of these diminutive moons of Mars from my back garden in Brisbane, around 22:00 on 6th October 2020. Intermittent clouds meant that I didn't record the LRGB frames until 1 hour later.:)
Mars is 6794.0 km in diameter and had an apparent size of 23 arc secs when I captured these images, shining with a magnitude of -2.57.
Phobos had a magnitude of 10.6 located some 30 arc secs from the disc of Mars, with Deimos a little dimmer at magnitude 11.7 and further away at 73 arc secs.
The larger moon is Phobos, a small, irregularly shaped object measuring just 22.7 km across with an orbit that places it closer to Mars than Deimos. Compared to Earth’s own Moon — which orbits at a distance of 384,403 km away from our planet — Phobos orbits at an average distance of only 9,377 km above Mars. Phobos is seven times more massive than Mars’s outer moon, Deimos.
Mars’ second moon is Deimos. It is even smaller, measuring just 12.6 km across, and is also less irregular in shape. Its orbit places it much farther away from Mars, at a distance of 23,460 km, which means that Deimos takes 30.35 hours to complete an orbit around Mars.
I have overlaid my LRGB image over the blown-out disc of Mars, which I had to grossly over-expose to record the much fainter moons. I have also uploaded a Screen Capture from SkyTools 4 Imaging to identify the moons.
Tak Mewlon 210 F11.5, Tak x1.6 Extender, ASI290MM Camera.
Cheers
Dennis
On that evening, Fear and Dread also stalked the night skies in Brisbane, namely the 2 small moons of Mars, Phobos (Fear) and Deimos (Dread). Both moons were discovered in 1877 by Asaph Hall. Ninety-four years later, NASA's Mariner 9 spacecraft got a much better look at the two moons from its orbit around Mars.
I managed to record images of these diminutive moons of Mars from my back garden in Brisbane, around 22:00 on 6th October 2020. Intermittent clouds meant that I didn't record the LRGB frames until 1 hour later.:)
Mars is 6794.0 km in diameter and had an apparent size of 23 arc secs when I captured these images, shining with a magnitude of -2.57.
Phobos had a magnitude of 10.6 located some 30 arc secs from the disc of Mars, with Deimos a little dimmer at magnitude 11.7 and further away at 73 arc secs.
The larger moon is Phobos, a small, irregularly shaped object measuring just 22.7 km across with an orbit that places it closer to Mars than Deimos. Compared to Earth’s own Moon — which orbits at a distance of 384,403 km away from our planet — Phobos orbits at an average distance of only 9,377 km above Mars. Phobos is seven times more massive than Mars’s outer moon, Deimos.
Mars’ second moon is Deimos. It is even smaller, measuring just 12.6 km across, and is also less irregular in shape. Its orbit places it much farther away from Mars, at a distance of 23,460 km, which means that Deimos takes 30.35 hours to complete an orbit around Mars.
I have overlaid my LRGB image over the blown-out disc of Mars, which I had to grossly over-expose to record the much fainter moons. I have also uploaded a Screen Capture from SkyTools 4 Imaging to identify the moons.
Tak Mewlon 210 F11.5, Tak x1.6 Extender, ASI290MM Camera.
Cheers
Dennis