Download SkyMatters Oct-2016 - CIT Blackrock Castle Observatory

SKYMATTERS
Blackrock Castle Observatory www.bco.ie
Download monthly skymatters newsletters from www.bco.ie/skymatters
Oct 2016
Things to watch out for
October 3-8
This year sees Ireland get a new National STEM Week (Science, Technology, Engineering and Maths) in the form of Space Week.
The week is coordinated by Blackrock Castle Observatory and part-funded by Science Foundation Ireland. The website is
www.spaceweek.ie. You can view events that have already been registered, or upload your own events, big or small. Organise an
event in your school or community and register your details on www.spaceweek.ie. We can help you with ideas! All registered
events will receive Space Week merchandise and promotional materials. Family-friendly events, roadshows, workshops and more
will take place nationwide
Space Week will enable all people to explore how, as 21st century citizens under one sky, we can use the power of critical thinking,
science, technology, engineering and maths to shape our understanding of life on Earth and our place in Space.
October 7
The Draconids is a small meteor shower produced by dust grains from comet 21P Giacobini-Zinner, discovered in 1900 by Michel
Giacobini, lost, and rediscovered 12 years later (two orbits of the comet) by Ernst Zinner while he was observing variable stars. The
optimum time to view this meteor shower is in the evening and although the shower lasts from 6-10 October, the evening of 7th is
predicted to be the peak. Meteors will appear to radiate from the constellation of Draco, but can be seen anywhere in the sky.
October 15
The planet Uranus, one of the outer giant gas planets, is closest to the Earth and is visible through a modest-sized telescope all
night long. The full Moon makes it slightly more challenging and it will appear with less contrast, hence showing less detail.
October 16
The Moon is full and is also a “supermoon”. The term denotes the fact that the Moon will appear larger as it rises and throughout
the night and the increased size is due to its relative closeness to the Earth in its elliptical orbit. Supermoons are accompanied by
slightly larger tides, due to the slightly increased gravitational influence of the Moon.
October 20-21
The Orionids meteor shower peak in the early hours of 21st October. The meteors originate from dust left behind by comet Halley
as the Earth crosses its orbit and ploughs into the debris from its last passage. The Orionids are a moderate shower, with up to 20
meteors per hour, but it is known for having a higher percentage of bright meteors. This is just as well, because the third-quarter
Moon will interfere slightly and make observing of the fainter meteors difficult.
October 30
The Moon is New and the skies will therefore be generally darker. This is a great time to observe — if it’s not cloudy!
Skychart for
October
The simplest way to use
the skychart is to find the
North Star (marked on the
chart as Polaris and circled red) in the real sky
and point the pole star on
our skychart in that direction.
The skychart is most correct for about 8 pm in the
middle of October 2016
(or 7 pm at the end of the
month or 9 pm at the beginning of the month).
The constellation of Auriga, the charioteer, is highlighted in green and the
brightest star is indicated
with an arrow. Although
Auriga rises just after dark
at the beginning of the
month, by month’s end it
is quite well placed from
10pm onwards.
Planets in October
Mercury is well placed on the eastern horizon in the morning sky at the beginning of the month, but by mid-month is lost in the glare of the Sun.
As always, be very careful if looking for Mercury and make sure there is no chance the Sun will make an unexpected appearance from behind
some horizon-skirting clouds, especially if you are using binoculars or a telescope. Mercury is very close to Jupiter on 11th.
Venus is not well placed for viewing in the evening sky this month.
Mars skirts close to the horizon all month long, though it is visible. It continues to fade as its distance from Earth increases.
Jupiter is a morning object. On 28th, between 6 and 7am it will be about a Moon’s diameter below a 4% crescent Moon, not high above the
horizon. This should make for a spectacular sight!
Saturn continues to become increasingly difficult to observe and is likely to be lost in atmospheric murk even when above the horizon.
Uranus is at opposition on 15th October, meaning it is closest to the Earth and in a direct line with the Sun. This also means the face of the
planet is fully illuminated. The planet is visible all night long.
Neptune is nicely placed throughout the month, but its extreme distance means it can only be viewed with a telescope.
Constellation to keep an eye on in October
The constellation of Auriga, the charioteer, is not one of the more
familiar constellations, in part because it sits next to two of the
most prominent winter constellations of Taurus and Orion. Neverthless, it is worth a look. Capella is the sixth brightest star in the
sky, but it is in fact a multiple star system. The star we see is actually two giant stars in orbit around one another, separated by a
distance of less than that between the Earth and the Sun. Farther
out from these two stars are another pair of stars which are small
and faint and called red dwarfs. Capella is only 42.8 light years
away from us, so it would be a target for a mission to look for life,
but it is hard to imagine that any planet could sit within this complicated system in such a way as to provide a stable basis for life to
exist.
Capella is a striking yellowish-white colour and although it is now
coming into the best time of year to observe it, it never actually
sets from Ireland and is a so-called circumpolar star. Look for Capella to the north-east after sunset.
Just below Auriga as it rises is the unmistakable
group of stars known as the Pleiades or Seven
Sisters.
The SuperMoon
The Moon orbits the Earth in an elliptical orbit. Elliptical orbits are by far the
most common types of orbit in the universe. For example, all the known planets in our solar system, and other solar systems (for which orbits have been
determined) are elliptical.
An elliptical orbit for the Moon is shown below. Note the level of ellipticity is
greatly exaggerated. You can see that at “perigee” the Moon is closest to the
Earth and at “apogee” it is farthest away. If the Moon is full when it is close to
perigee it is called a supermoon (see left). However, the size of the Moon is
always varying because of its variable distance, whether it is a full Moon or
not. It’s just that we notice a full Moon more than, say, a first or third quarter
Moon. So although the tides are indeed larger for a supermoon, because the
Moon is closer and exerts a slightly (very slightly) larger gravitational pull on
the Earth (including our oceans) at perigee, it does this once a month anyThe size difference between the average Moon (left) and a
supermoon (right). Image by Marco Langbroek of the Nethvia Wikimedia Commons.
Iterlands
s
how, whether it’s a supermoon or not!
Since all the planets in the solar system vary their distance
from the Earth, they too undergo a kind of “supermoon” phenomenon. This month, on 15th, the planet Uranus is closest
to the Earth, so perhaps we should refer to that as a “superuranus”.
Space Week
Website of the month
You can participate in Ireland’s first Space Week between 3-8 October. There are lots of
interesting and exciting events to participate in all across the country and most are completely free. If you have an idea for an event yourself, just REGISTER on the website and
you will receive some support material to help you along. If you don’t have an idea, but
are rather looking for some, then the website has lots of ideas for you to consider.
With October heralding the arrival
of Space Week, we have chosen
this site as the one to explore this
month. But you are not only able
to explore it—you can add to it by
uploading a space week event!
URL: http://www.spaceweek.ie
Quote of the month
#SpaceWeek16
"Circling the Earth in my orbital
spaceship I marvelled at the
beauty of our planet. People of
the world, let us safeguard and
enhance this beauty — not destroy it!"
Yuri Gagarin, 1st human in space
Some Upcoming Events at CIT Blackrock Castle Observatory
Junior Space Camp | October 2 | 12:00 – 13:30
Check for new sessions on Oct 2. Our hugely popular Junior Space Camp is amazing science with an intergalactic
twist! We’re going to take a journey into Space and give our budding space enthusiasts a chance to explore and
experiment with science. Suited to 5 – 7 year old’s. €10 each (one parent is required to stay). Booking advised.
Spooky Space Camp | October 30 | 12:00 – 13:30
Our Junior Space Camp with a Halloween twist. Make Monster Volcano’s and Lava Lamps as well as the usual Magnet Painting and Mentos Rocket! Suited to 5 – 7 year old’s. €10 each (one parent is required to stay). Booking advised.
Planetarium Shows | Daily | 12:00, 14:00 16:00
Discover the wonders of the night sky in our live planetarium shows. Shows are included in your admission ticket.
Castle Tower Top & Gunnery Tours | Daily | 11:30, 13:30 15:30
Blackrock Castle is the oldest surviving structure still in use in the city of Cork; a 16th century fort turned robotic
observatory and science centre with panoramic views of Cork Harbour. Your tour guide will bring the past, present
and future together and take you on a trip back through the colourful history of Blackrock exploring over 400 years
of Cork Harbour stories. Tours are included in your admission ticket. Be one of the first to experience our new
“Journey’s of Exploration” exhibit.
PUBLIC OPENING Hours: 10:00 – 17:00 (Mon- Sun) Phone: 021-4326120 / Email: [email protected]
Blackrock Castle Observatory is operated by Cork Institute of Technology in partnership with Cork City Council.