Tag Archives: orbit

sunrise photos: mistymuse encore

I wasn’t expecting to see the sunrise this morning, but hadn’t remembered until seeing the sun that British Summer Time (BST) had started eleven days ago, requiring we turned time on an hour, meaning the sunrise also went on an hour, from 5.51 on the 27th to 6.48 (would’ve been 5.48, as first sight of the sun is about 2/3 minutes earlier per day) on the 28th.

Eleven days later, the ‘sunrise’ today was at 6.24. The ash tree (Yggdrasil) is now budding, and very popular with the birds!

Sun’s Journey Over A Month (Really it’s our orbital journey and changing view)

The ‘sunrise’ continues up the horizon though. Although it seems to be departing for me, earlier and nearly out of sight, for the northern hemisphere as a whole it is in fact more visible; earlier and for longer.

Comparing it to this photo from March 6th (last year, but it’s roughly the same every year) shows how much farther up the horizon it ‘rises’ over a month. This morning it rose between the two trees under ‘Yggdrasil’, where the arrow points.


Midwinter Until Spring Equinox creates the MUSE part of mistYmuse. The first part consists of Most Ideal Sunrise Times, and they seem a long time ago now. The sunrise times have retreated from about 08.30 to just after 6. Really, it’s just our first sight of the sun, with the northern hemisphere now tilted towards our star, as it continues its regular orbit.

This is our current position in the solar system according to theplanetstoday:

In midwinter we were at 12 o’ clock, with the northern hemisphere mostly pointed out to space. That meant the northern hemisphere had a lower share of sunlight than the southern. Now we are equal.

After this second instalment of the mistYmuse closing day ceremony is quite serious; like a band playing a slower number mid set; I can promise a rocking third post to bring the curtain down on mYm 20/21.

winter solstice light clocks

Light clocks ideas using a world to a 12 hour clock face, basically divided by the north and south hemispheres. The original one has numbers around it, but going anti-clockwise, as the Earth goes around the sun. It has a 0-6 measurement.

However, then I thought that some light even gets to the poles in mid-winter, so I thought I’d use a 12 measurement system, with 3 the lowest rating.

I couldn’t see anything like it online, so is it original… and worth thinking about? Or has it been thought about, but not been considered worthy?

Planets race tonight and year

Jupiter and Saturn visibility has travelled across the southern sky over the year, westward from south-east to middle now: that’s because they’re on the ‘outside lane’ and we’re overtaking on the inside. In contrast to our year (365 days; time measurement created by humanity of course) orbit it takes Jupiter 11.86 years to orbit the sun, and Saturn 29.50, so they are not always seen close together like that; Jupiter will ‘race’ ahead of Saturn.

They also look like they’re travelling westwards each night, but that’s because of our planetary spin. In contrast, Venus is on our inside, taking only 224 ‘days’ to orbit the sun, so is racing ahead, looking as if it’s travelling eastward on our horizon over the year.

It was Galileo’s observations of the full planetary phases of Venus in 1610 that determined planets orbit the sun, rather than Earth.

Venus still looks as if it’s travelling west through the night though, because that’s defined by our planetary spin. As Jupiter lags behind us we see it earlier as our planet twists around anti-clockwise:

Jupiter 12.49 (November 5th) to 11.07 (December 5th)
As Venus races ahead, we see it later:
Venus 3.54 (November 5th) to 5.32 (December 5th)

Eventually, Venus will go out of sight behind the sun, reappearing in our evening as it catches up with us again. This year (2020), space.com writes Venus was in our: Evenings in the western sky at dusk from January 1st to May 24th; mornings in the eastern sky at dawn from June 13 to Dec. 31.


Summer solstice great greenygreying

It’s summer solstice, with our planet’s northern hemisphere getting its most sunlight because it’s axis tilt is tipping it more towards the sun than any other time on its orbit around our star, the sun.
My favourite orrery, the planets today, shows the sun at 6 o’ clock now, going anti-clockwise:

Sun Returns to Arctic Circle: Welcome to mistYmuse 2020!

Tromso, a Norwegian Arctic Circle municipality I visited for midsummer in 2007, can see the sun again, having enjoyed only the first week of mistYmuse (Most Ideal Sunrise Times – Midwinter Until Spring Equinox) 2019. The Arctic Circle was facing away from the sun so much, Tromso could not see the sun (no ‘sunrise’) between November 27th and January 15th.

Although our planet spins around on its axis (making the ‘time of day’) the tilt stays the same; north to south; so our planet orbits the sun like a human partly elevated on a bed circling something. As shown in this seasons image:

As our planet orbits in the solar system, our axis tilt is now returning the north to facing the sun, reaching parity of light with the south at the spring (north) / autumn (south) equinox: this year on March 20th.


Poem about North South Sky Space Constellations

English: This is the Crux (Southern Cross) con...
Image via Wikipedia

Marc Latham’s latest Folding Mirror poem has space constellations as its subject. Some constellations can only be seen in either the northern or southern hemisphere sky on Earth. Others can be seen from all over the planet, but in the opposite seasons of the two hemispheres (e.g. summer in the north and winter in the south).
As winter becomes spring in the north, and summer becomes autumn in the south, constellations such as Orion, Taurus and Gemini will be leaving the night sky, and constellations such as Cancer, Leo and Lynx will become visible again.
The poem was recently inspired by the BBC’s Orbit documentary, and was mainly researched on the Dome of the Sky website. Here’s it is:
Constellations of the North and South
North Pole darkest skies
have exclusive views for eyes
Camelopardus, Cepheus, Cassiopeia,
only seen from Earth’s northern hemisphere
Triangulum, Ursa-Major, Draco
are another trio
Anquila, Antlia, Auriga,
northern spring, summer, autumn, winter
straddle the equator, visible to all, signifying seasons
southern autumn, winter, spring, summer
Vela, Virgo, Vulpecula
travel way below
Triangulum-Australe, Norma, Dorado
visible solely in planet’s southern section
Circinus, Crux, Chamaeleon,
tell astronomers they observe space
South Pole night-time face
Marc Latham’s central site is the Greenygrey (http://www.greenygrey.co.uk)