Starship Asterisk*

The Solar System's Planet Trails

Explanation: Stars trail through a clear morning sky in this postcard from a rotating planet. The timelapse image is constructed from consecutive exposures made over nearly three hours with a camera fixed to a tripod beside the Forbidden City in Beijing, China on June 24. Arcing above the eastern horizon after the series of exposures began, a waning crescent Moon left the brightest streak and watery reflection. On that date the planets of the Solar System were also lined up along the ecliptic and left their own trails before sunrise. Saturn was first to rise on that morning and the ringed planet's trail starts close to the top right edge, almost out of the frame. Innermost planet Mercury rose only just before the Sun though. It left the shortest trail, visible against the twilight near the horizon at the far left. Uranus and Neptune are faint and hard to find, but mingled with the star trails the Solar System's planet trails are all labeled in the scene.

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The Earth: The only planet in the solar system whose natural satellite leaves a brilliant reflective trail in the planet's liquid water.

Ann

2022! June; the month of the planets! My biggest problem is spotting
Mercury so tiny in the sky and can only be seen in the early Dawn
and Dusk! it is neat when you do find it!

Ann wrote: ↑Fri Jul 01, 2022 6:14 am The Earth: The only planet in the solar system whose natural satellite leaves a brilliant reflective trail in the planet's liquid water.

Although it is interesting to consider Titan, the only natural satellite in the Solar System whose parent planet leaves a brilliant reflection in the moon's liquid methane! (But never a trail. And maybe not in most of the visible spectrum.)

The image of the day gives me the opportunity to make a geometric construction of the latitude of the place with the traces of the stars. Here I take the line of Jupiter because it is the most straight to which I lower a vertical that, together with its route, draws an angle that corresponds to the value of the local latitude. Beijing is at 39º54' and the value taken is 40º with minor error and as the angle opens to the right it is the northern hemisphere (in the southern hemisphere the angles open to the left)

This way you can know the latitudes of the different places in the world

Chris Peterson wrote: ↑Fri Jul 01, 2022 1:59 pm

Ann wrote: ↑Fri Jul 01, 2022 6:14 am The Earth: The only planet in the solar system whose natural satellite leaves a brilliant reflective trail in the planet's liquid water.

Although it is interesting to consider Titan, the only natural satellite in the Solar System whose parent planet leaves a brilliant reflection in the moon's liquid methane! (But never a trail. And maybe not in most of the visible spectrum.)

What do you mean by "but never a trail"? If there was a camera running a long exposure on Titan with a view of Saturn in the appropriate wavelength, wouldn't it leave a trail of Saturn on the film/CCD?

johnnydeep wrote: ↑Fri Jul 01, 2022 9:01 pm

Chris Peterson wrote: ↑Fri Jul 01, 2022 1:59 pm

Ann wrote: ↑Fri Jul 01, 2022 6:14 am The Earth: The only planet in the solar system whose natural satellite leaves a brilliant reflective trail in the planet's liquid water.

Although it is interesting to consider Titan, the only natural satellite in the Solar System whose parent planet leaves a brilliant reflection in the moon's liquid methane! (But never a trail. And maybe not in most of the visible spectrum.)

What do you mean by "but never a trail"? If there was a camera running a long exposure on Titan with a view of Saturn in the appropriate wavelength, wouldn't it leave a trail of Saturn on the film/CCD?

Titan is tidally locked (like the Moon) and always keeps the same face toward Saturn. So where Saturn appears in the sky depends on your location, but for any given location doesn't change with time.

Chris Peterson wrote: ↑Fri Jul 01, 2022 9:13 pm

johnnydeep wrote: ↑Fri Jul 01, 2022 9:01 pm

Chris Peterson wrote: ↑Fri Jul 01, 2022 1:59 pm

Although it is interesting to consider Titan, the only natural satellite in the Solar System whose parent planet leaves a brilliant reflection in the moon's liquid methane! (But never a trail. And maybe not in most of the visible spectrum.)

What do you mean by "but never a trail"? If there was a camera running a long exposure on Titan with a view of Saturn in the appropriate wavelength, wouldn't it leave a trail of Saturn on the film/CCD?

Titan is tidally locked (like the Moon) and always keeps the same face toward Saturn. So where Saturn appears in the sky depends on your location, but for any given location doesn't change with time.

Aha! Thanks.