Items Featured In TGP NOMINAL Xtra - August Skies 2020
Comet C/2020 F3 (NEOWISE) :
There were a couple of comets, that you might have heard about.
They were meant to put on a show and people have been talking about them.
One was called C/2019 Y4 (ATLAS), which was meant to be nice and bright.
But unfortunately just as it started brightening, it started to disintegrated.
Because the sun heat it up and probably turned into water water vapour,
because it was made up of Ice and stuff flying around the sun.
Then there was another one called C/2020 F8 (SWAN), Which didn't seem to really get bright enough,
to create that WOW! Factor.
Then suddenly, from out of nowhere, came Comet C/2020 F3 (NEOWISE).
It's a long period Comet, which was discovered on March 27th, which at the time was just a very faint object,
but by July it completely stole the show when it became an object you could see with the naked eye.
It was meant to be at it's brightest on July 23rd, because that's when it would be nearest to the Earth,
but because it's also moving further away from the sun, it's actually started dimming.
By the beginning of August, when this podcast goes out, you probably won't be able to see it unless you have a telescope.
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NEOWISE is a really strange name for a comet and the reason why it's called NEOWISE is that NASA discovered the Comet using a space probe, which was tasked with looking for Near Earth Objects, called NEOWISE.
As we all know NASA love using Acronyms and NEOWISE is an acronym made from,
Near Earth Object (NEO) and Wide-field Infrared Survey Explorer (WISE).
A lot of people in the UK Astronomy Facebook Group have been asking how to take pictures,
so UK Astronomy have recently purchased a Nikon D3500 DSLR Camera,
so that Ross could learn Astrophotography and eventually teach the skills he picks up.
Ross has been learning from UK Astronomy's very own Astrophotographers 'Wil Cheung' and 'David Pickles' and was really proud of his first attempt.
The Perseid Meteor Shower:
So on to this month, August only means one thing.
The Perseid Meteor Shower
Meteors or shooting stars happen every night,
but a shower is a special event where the amount you can see increase dramatically.
We have these all through the year but some like this month's Perseids, produce more than others.
To understand why, we need to start by looking at comets like C/2020 F3 (NEOWISE)
A comet is a relatively small solar system body but plays a large part in this month's shower
Although meteorites look pretty spectacular as they streak across the skies,
they are pretty much just dust particles that come from the decaying surfaces of comets.
As a comet gets closer to our Sun it's surface starts to heat up and snow (Yes snow!) just below the surface
turns into a gas which then escapes,
breaking up the surface of the dusty nucleus of the comet, blowing these particles away from it.
These particles form a stream all around the original path or orbit of the comet,
which increases with each pass of the comet, again and again.
The larger the comet or more volatile, the denser the stream is.
Our inner solar system is full of these comet streams and as the Earth orbits the Sun it often passes in and out of theses streams of decayed comets colliding with some of these meteoroids creating shooting stars.
So on to this month, August only means one thing.
The Perseid Meteor Shower
Meteors or shooting stars happen every night,
but a shower is a special event where the amount you can see increase dramatically.
We have these all through the year but some like this month's Perseids, produce more than others.
To understand why, we need to start by looking at comets like C/2020 F3 (NEOWISE)
A comet is a relatively small solar system body but plays a large part in this month's shower
Although meteorites look pretty spectacular as they streak across the skies,
they are pretty much just dust particles that come from the decaying surfaces of comets.
As a comet gets closer to our Sun it's surface starts to heat up and snow (Yes snow!) just below the surface
turns into a gas which then escapes,
breaking up the surface of the dusty nucleus of the comet, blowing these particles away from it.
These particles form a stream all around the original path or orbit of the comet,
which increases with each pass of the comet, again and again.
The larger the comet or more volatile, the denser the stream is.
Our inner solar system is full of these comet streams and as the Earth orbits the Sun it often passes in and out of theses streams of decayed comets colliding with some of these meteoroids creating shooting stars.
The Perseids are associated with the comet called 109P/Swift-Tuttle,
and once again it was named after the people who discovered them.
Lewis Swift and Horace Parnell Tuttle discovered comet 109P/Swift-Tuttle in 1862 .
Comet 109P/Swift-Tuttle has an orbital period of around 133 years and was last seen in 1992,
but wont be seen again until 2126 which means most of us won't be seeing it.
Now, to have created such a splendid amount of dust to cause the Perseid meteor shower,
the comet must have been on the same path a few hundred times in a 133 years.
But why do these tiny bits of dust create such amazingly spectacular displays in our skies?
When a meteor enters our atmosphere it goes from travelling through the vacuum of space with no friction, to travelling through air which as we know does create friction, quite a lot of friction.
They generally travel at tens of thousands of km’s per hour but when they hit earth,
the air in front of it compresses incredibly quickly, and when a gas is compressed its temperature heats up,
causing the meteor to as well.
It starts to glow, the air will continue to burn the meteor until nothing is left,
which is the streak you see across the sky.
These re-entry temperatures can reach 1650 degrees Celsius, and larger particles may burn even brighter possible popping in the sky bursting leaving smoke trails. Often called fireballs.
Now if the meteor weighs over 30kg then only the surface layers are lost during re-entry where our atmosphere eventually slows it down to around 90mph. This is known as freefall.
And it hits the ground becoming a meteor-ite,
There are three classifications of Meteorites
1. STONEY METEORITES – MOST COMMON AT 93% OF METEORITES SO FAR FOUND
2. IRON METEORITES – WHICH ARE RARER AT 5% OF METEORITES
3. STONEY-IRON METEORITES
Stoney- Iron Meteorites are the rarest of the three and have a similar compostion,
to the Rocky Planets in our and other Solar Systems.
So why is it called The "Perseid" Meteor Shower?
The Perseids are named due to the location in the sky from where the meteors radiate.
They are are so named, because they seem to come from the constellation Perseus.
The Constellation Perseus is named after the Demigod (The offspring of a God and a Human) Perseus in Greek Mythology.
Check out the video above, to find out about the legend of Perseus
How do we see them?
Beauty of this event is you don’t need any equipment, just grab a coffee or hot chocolate,
grab the kids and go out into your garden or a nice dark field and look up.
The peak of the shower happens in the middle of August usually 12/13, but we entered the dust stream in July,
and won’t leave it until the end of August.
So the shower of meteors slowly builds up each night to its peak, then slowly dwindles back to normality.
Perseus rises pretty much from when the sunsets (say around 10pm) onwards, to the North East.
If you don’t have a compass handy, put your left arm out towards the setting sun,
your right arm straight out the opposite side,
bring them both together in front of you and look up.
Slightly to your right, you should see a slightly skewed W in the sky.
This is the Constellation Cassiopeia (The Vain Queen), Perseus is just below this.
As the night goes on, Perseus rises and so you will get a better chance to see the meteors, later in the night.
(around 2am will be best so set an alarm and get a hot drink)
What can we expect to see?
Well every year, the press predicts 100-120 meteors an hour but..... you are never going to see this amount,
because of light pollution.
The moon won't be too much of an issue isn’t to bad this year as it will be rising as a crescent, around 2am.
In the past Ross has counted 67 meteors, in around an hour and a half.
But its a unpredictable dust lane left by a comet with dense areas within it. So you never know!
We are currently passing through a cloud of dust particles left by a decaying comet,
hundreds if not thousands if not millions of years old orbiting our Sun.
As you are sat listening to the podcast or out looking at the skies,
Remember, you are travelling at around 30km per sec through this stream.
So if it takes a few weeks to properly pass through the densest part of the Perseid stream…
I calculate that it must be, ….
PRETTY DAMN BIG!
Just think, you are seeing pieces of a comet burning up in our atmosphere as our planet passes through its path,
and it only takes one slightly larger piece to create a stunning display that you’ll remember for ever.
And while you are out there, there are also a few planets up.
Saturn and Jupiter will be a easy spot, so grab a pair of binoculars or a scope and you will see,
Jupiter’s four main moons and even Saturn’s rings.
Even with a small scope or steady handed binoculars you may see Mars and if up later maybe Venus.
We will have guides up on the UK Astronomy website and Facebook Page,
if you’d like to find out more about the stars and all our soon to be upcoming events.
Ross Hockham's August Sky Guide:
It’s possible to see all 8 planets in one night this month (9 if you look at the ground).
Mercury is a hard spot, rising just before the Sun.
It's very low down and it's starting to back towards the Sun and can only be seen in beginning of the month.
Be Careful when looking towards the Sun.
DO NOT LOOK DIRECTLY AT IT!
Venus rises around 2am, to the east and will be brightest thing in the morning sky.
Mars rises around 11pm. You will see an orange-redish blob to the left of Jupiter and Saturn.
Saturn and Jupiter will be easy spots as the sun sets, you will see 2 white blobs next to each other.
Uranus is just left of Mars below the star Hamal in the constellation Aries but you will need a scope to see it.
Neptune is a harder find being to the right of Mars in between Aquarius and Pisces a bit of star hopping will be needed.
PLUTO is technically not a planet as such (#Planet9) but it is literally in-between Jupiter and Saturn,
at the beginning of the month.
So let's have a look at what else is happening in the skies through the month
That’s it for this month Happy Meteor Hunting!
Ophiuchus, The 13th Tribe of Kobol? :
Over 3,000 years ago, The Babylonians created the Zodiac and divided it into 12 equal parts.
Like cutting a pizza into 12 equal slices.
They picked 12 constellations in the zodiac, one for each of the 12 “slices.
So, as Earth orbits the sun, the sun would appear to pass through each of the 12 parts of the zodiac.
Since the Babylonians already had a 12-month calendar (based on the phases of the moon),
each month got a slice of the zodiac all to itself.
But even according to the Babylonians’ own ancient stories, there were 13 constellations in the zodiac.
So they picked one, 'Ophiuchus', to leave out.
Even then, some of the chosen 12 didn’t fit neatly into their assigned slice of the pizza and crossed over into the next one.
When the Babylonians first invented the 12 signs of zodiac, a birthday between about July 23 and August 22,
meant being born under the constellation Leo.
Now, 3,000 years later, the sky has shifted because Earth’s axis (North Pole) doesn’t point in quite the same direction.
The constellations are different sizes and shapes, so the sun spends different lengths of time lined up with each one.
The line from Earth through the sun points to Virgo for 45 days, but it points to Scorpius for only 7 days.
To make a tidy match with their 12-month calendar, the Babylonians ignored the fact,
that the sun actually moves through 13 constellations, not 12.
Then they assigned each of those 12 constellations equal amounts of time.
So, NASA didn’t change any zodiac signs…They just did the maths.
So Say We All!
Recently 'Janelle Harrier Wilson' TGP NOMINAL Honorary Crew Member,
UK Astronomy Volunteer and NASA Solar System Ambassador,
appeared on BBC Three Counties Radio to chat with radio Presenter Robert Peroni about Ophiuchus.
Click Here to listen to the interview.
The Space Crafter Cometh:
Here's a little teaser of what The Space Crafter is all about! We hope to bring you more about this beast soon.
Also keep an eye on the UK Astronomy website and Facebook Page,
for more information on when The Space Crafter launches.