The winter solstice. Image credit: http://commons.wikimedia.org/
This evening at 23:03 UT winter officially starts in the northern hemisphere with the winter solstice.
The solstice occurs when the northern hemisphere of the Earth is inclined at a maximum angle (23° 26′) away from the Sun and results in the shortest period of daylight. In fact, for residents within the Arctic Circle, 24 hours of darkness occurs and for those on the Tropic of Capricorn, the Sun will be directly overhead. After the winter solstice, the daytimes lengthen and the nights become lighter and shorter.
The opposite occurs in the southern hemisphere that sees the summer solstice at this same time. The reverse of this event occurs with the northern solstice on June 21st 2015 at 16:38 UT.
The company that hosts the society website and forums will be migrating servers throughout Wednesday 5th November. During this move, the society website will be unavailable for a small amount of time at some point during the day. The only effect on users will be a duration of unavailability.
Apologies in advance for any inconvenience this may cause.
British Summer Time (BST) finishes on Sunday 26th October 2014. The clocks change at 2am, moving back an hour onto Greenwich Mean Time (GMT).
The effect is darker evenings and lighter mornings. Astronomy software such as planetarium software and GoTo mounts may need to be configured to account for no daylight saving time in operation.
Society secretary Andy Exton FRAS visited the Wharfe Beavers of Westborough Methodist Church in Scarborough on Friday 26th September.
The Space Activity Badge is a newly launched badge from the Scout Association for Beavers and this was the first group that SARAS have assisted in achieving.
The requirements of the badge are as follows:
- Identify some of the things you can see in the night sky, for example stars, planets and the Moon.
- Identify at least one constellation you can see.
- Be able to name the eight planets in our solar system.
- Find out about a current space mission.
The group had previously visited the Scarborough Star Disk in the South Bay to learn about some of the constellations visible in the night sky and had made their own Solar System models. Andy helped them learn more about the planets and moons in our Solar System, some of the recognizable constellations visible from Scarborough and gave some info on current space missions including the International Space Station, Curiosity, Rosetta, MAVEN, Mangalyaan and New Horizons.
If any other local scout groups require assistance with space and stargazing activity badges, please do get in touch.
Posted in News, Public Outreach, Scouts / Guides
Tagged Andy Exton FRAS, Beavers, Curiosity, International Space Station, Mangalyaan, MAVEN, moons, New Horizons, Planets, Rosetta, Scarborough Star Disk, Solar System
Illumination of the Earth during an equinox. Image Credit: http://en.wikipedia.org/wiki/File:Earth-lighting-equinox_EN.png
02:29 UT (03:29 BST) sees the Southward equinox. For ourselves in the Northern Hemisphere, it is known as the Autumnal equinox and the Vernal or Spring equinox for residents in the Southern Hemisphere. The Sun falls on the Celestial Equator during the Autumnal equinox resulting in equal lengths of day and night across the planet. From today on-wards as the name suggests, the Sun is seen to be moving southwards, resulting in shorter days and longer nights for us.
The Celestial Sphere. Image credit: http://www.kirchdorferweb.com
The point on the Celestial Equator where the Sun lies during the Vernal equinox is known as the First Point of Aries. However, due to precession (the continued change in the rotation of the planet on its axis), the Sun is no longer in the constellation of Aries and has not been since around 100 BC. At the moment, the Sun is in the constellation of Pisces and by the year 2600 it will be in the neighbouring constellation of Aquarius.
As the Sun rises at an equinox, the Sun will appear to cross the horizon due east and recrosses the horizon at Sunset due west. Over the next 3 months leading up to the Winter or December Solstice, the Sun will appear to rise and set further to the south of these points as it appears to follow the path of the ecliptic. It will then move back north approaching the northward equinox in March when the Sun will again rise and set due east and west respectively.
Posted in News
Tagged Aquarius, Autumn, autumnal equinox, celestial equator, celestial sphere, ecliptic, first point of Aries, northward, Pisces, precession, solstice, southward, Vernal equinox