Cuir
do spòg an-seo airson a dhol air ais dhan duilleag dhachaigh
Tha ùidh air a bhith agam ann an
reul-eòlas bhon uair a bha mi nam leanbhach.
Airson mo naoitheamh co-latha breith, chaidh ar teaghlach gu
beachd-ionad nan reul ann an Dùn Èideann.
Chan eil mi airson cus sgriobhaidh mu dheidhinn a’ chuspair seo, ach tha
mi’ n dòchas gun còrd na dealbhan ribh.

A’ Ghealach
‘S e na planaidean a bha a’
chiad rud air an robh ùidh agam a thaobh reul-eòlas. Tha mi cinnteach gu bheil fios agaibh gu bheil naoi dhiubh anns
an t-siostam grèine againn… Mairciuraidh, Bhionas, Talamh, Màirt, Iùpatair,
Sathairne, Uranas, Naiptiùn agus Plùto.
Tha ceithir planaidean beaga a lorgamaid nas fhaisge air a’ ghrèin. Sin a’ chiad ceithir a dh’ainmich mi. ‘S e ar planaid fhèin, Talamh, an tè as
motha a-mach as na ceithir. ‘S e
Mairciuraidh as fhaisge agus as lugha (mur a h-eil sibh a’ cunntadh
Plùto). Tha e iongnantach gu bheil
Bhionas nas teotha na Mairciuraidh. ‘S
e an t-àile aig Bhionas as coireach airson sin.

Mairciùraidh
Seo dealbh de Bionais fodha:
Here’s a picture of Venus below:

Bhìonas
Mar a tha sibh a’ faicinn, tha e
mar theine. Tha diofair mhòr eadar an
taobh fuar agus an taobh a dh’ionnsaidh na grèine. Bidh e 400˚C air a’ ghrunnd.

An Talamh
Agus mu dheireadh a-mach as a’
chiad ceithir planaidean, Màirt, ‘s e a’ phlanaid as coltaich ri ar tè fhèin a
th’ ann am Màirt. Tha e ro fhuar
ged-tà, agus chan eil ocsaidean gu leòr ann.

Màirt
Eadar Màirt agus Iupatair,
lorgamaid tòrr bheag-phlanaidean (asteroids) ‘s e ‘the asteroid belt’ a’
Bheurla air seo.
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Beag-Phlanaid
‘S e Iupatair a’ phlanaid as
fheàrr leam. ‘S e a’ phlanaid as motha
a th’ ann, agus tha e làn rudan inntinneach.
‘S docha gu bheil sibh uile eòlach air an ainmeil smal dearg. ‘S docha nach eil fios agaibh gur h-e
mòr-ghaoth trì tursan nas motha na an talamh.
‘S e planaid dèante dìreach le gas, agus fada nas motha na ar talamh.

Iùpatair
‘S e Sathairne a’ phlanaid as
motha as dèidh Iupatair. Tha e ainmeil
airson nam fàinne. Chan eil mi cho
cinnteach fhèin carson a tha fàinneachan mun chuairt Shathairne. Tha fios agam gu bheil fàinneachan mun
chuairt na ceithir planaidean as motha, Iupatair, Sathairne, Uranus agus
Naiptiùn.

Sathairne
‘S e Uranus agus Naiptiùn an ath dhà phlanaid:

Uranus (os chionn) agus
Neaptiùn (fodha)
Agus mu dheireadh, saoghal
dorch, planaid neònach agus iomallach, faisg air sia mìle millean ciolometeran
bhon ghrèin, ‘s e Plùto:
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Plùto
Tha e a’ cosg ochd mionaid
airson solas a bhith gar ruigsinn bhon ghrèin, agus tha sin còrr is 149 millean
kilometre air falbh bhuainn! Ann am
facal tha sin a’ ciallachadh gu bheil solas a’ siubhal aig astar 200,000,000
mìle gach diog! Naoi turas mun chuairt
na talmhainn ann an dìreach aon diog!
Tha an rionnag as fhaisg oirnn (às dèidh na grèine) 4.3 ly (light-year)
air falbh. ‘S e Proxima Centauri an
t-ainm a th’ oirre. Tha sinn air ar lorg
air fear de na casan a tha mar cuairteachan (spirals) mun chuairt ar galacsaidh.

Chruinneachadh mòr de reultan
(Galacsaidh)
You can see just how densely
compact all the stars are. There are
literally trillions of stars in our galaxy, each one dwarfing our planet. When you consider that then there are
billions of galaxies, we begin to realise how small we are. The latest thinking is that there is an
enormous blackhole at the centre of the galaxy. Blackholes have almost infinite gravity, which is why light can’t
escape. Sometimes they are incredibly
small, only a few miles in diameter, but don’t underestimate them. They are powerful enough to suck in whole
stars. A blackhole is effectively a
star which has first exploded as a supernova, then collapsed into itself under
it’s own weight. They obviously can’t
be seen, by definition, light can’t escape and therefore they don’t emit
light. They are detected by their
gravity. Here is a spectacular
supernova (exploded star):

Mòr-spreadhadh reul/Supernova
These events are not very
common, but occur all over the galaxy.
Stars emit different colours because they burn at different
temperatures. Red stars tend to be
cooler than white ones. You get stars
of all different sizes. The Sun is a
relatively small one. Most of the
matter in the universe is so called ‘dark-matter’, matter that does not emit
light. It is detectable only by it’s
presence. It could be vast quantities
of cosmic dust. The Hubble Space
Telescope was a major breakthrough in the astronomy world. For the first time it allowed us to look far
into the depths of the universe.

Dealbh gu math farsaing de
mhòr-chruinneachaidhean de reultan
A wide picture showing many
galaxies
The above picture is a vast area showing many galaxies, each one
containing billions of stars, each star dwarfing the Earth. It is a series of pictures taken by the
telescope.
Galaxies cluster together.
This is because of gravity. All
things (matter) with mass have a gravitational pull. We can see this by the pull between the Earth and Moon. It is the gravitational pull of the Moon,
which causes waves in our planet’s oceans.
In my opinion the universe is expanding at an ever-increasing rate,
caused by the lessening effect of gravity, as the galaxies grow further away
from each other. As the gravitational
pull lessens, there is less to hold them back, and therefore move away at a
quicker pace, the more they do this, the lesser the effect of gravity, and the
further apart they spread. My thought
about the fate of the universe is that it will continue to do this for
eternity, eventually becoming a very dark place. There are others who believe that the universe is expanding at a
constant rate, others who believe that it is expanding at an ever decreasing
rate and even some who think that it will eventually start to reverse, and
implode on itself.