Digital illustration of a comet. Didn’t want to use someone else’s copyright photo. This is just to give an impression of its colour….
I get alerts from Spaceweather.com about all sorts of astronomical events. I got this alert about a comet this morning. As we are in ‘interesting times’ I thought I would let you know.
Here is a short excerpt with the link:
COMET ATLAS IS BRIGHTENING FASTER THAN EXPECTED: Get ready for a wild ride. Comet ATLAS (C2019 Y4) is plunging toward the sun and, if it doesn’t fly apart first, it could become one of the brightest comets in years. Amateur astronomers are already getting fantastic images as the comet brightens even faster than expected. Visit Spaceweather.com for the full story.
I don’t think the link will work from here, but it’s an easy address to find.
‘space’, digital drawing’
I was sitting thinking about dark matter and dark energy today as you do. I’m not sure exactly what they are, but scientists are trying to find out.
To explain, normal matter only takes up a small percentage of the amount of matter in the universe. The rest could be ‘dark matter’ which cannot be measured by normal scientific measures. Also there is dark energy. A type of energy that is repulsive. The universe is expanding and this dark energy is apparently speeding that process up.
Then I thought about the idea that there may be more than one universe. The multiverse. In some theories each decision we make could create a new universe. But we can only see the one we are in? My mind started to boggle. Maybe the dark matter could be from the universes we can’t see, and the dark energy from the creation of each new universe’s.
This is the trouble with speculation, I don’t know whether any of this makes any sense. But I like thinking, and if it takes my mind off the world at the moment, then maybe it’s a good thing.
What’s in a cage,
and what is a cage?
Are we trapped in a net,
Are we birds in cages
or enclosed by space?
How big is your cage?
Can you walk across a room?
Are their bars on your window?
Is there no way out.
Are you stuck in your mind?
Many cages exist,
some are visible,
some are in your mind…
Would you buy a painting of one of the poles of Jupiter? I’ve done a few paintings os astronomical objects. This is from a photo from the Juno probe a few years ago. I’m thinking if doing a ainting of Pluto’s heart. But although I love it I wonder if anyone out there is actually interested. Maybe I’m too interested in tech. I can’t help it though.
It’s not easy to hand paint these images, it takes ages to blend the colours and build them up. Then you have to make sure it’s accurate, although I don’t measure everything exactly. I can’t compete with photography but I do try my best. Anyway this is a large acrylic on canvas and it is for sale.
So how can you tell the Earth is a sphere? The ancient Greeks worked it out ( I don’t remember the name of the person who did).
The experiment was to put a stick in the sand at or near the equator, so it would have a tiny shadow directly underneath the it at mid day as the Sun was directly overhead.
If you place a stick upright, at 90° to the Eaths surface either North or South of the equator, the stick casts a shadow at mid day. (Look at the hands of a clock the hands move round in the same way). Say the equator is 3pm and the Sun is overhead, you would get no shadow, then as you go further away from the stick at the equator you get increasing angles (see diagram). Eventually at the poles the shadows would be at their longest.
So how can you tell its a sphere? The angles add up. You can calculate the curvature of the planet from these simple experiments. The ancient Greeks got very close to calculating the circumference of the Earth. Their calculations were only a small percentage out on their measurement.
Betelguse the star is shrinking.
Fainting they say.
On the shoulder of Orion,
it’s getting fainter.
obese and middle aged?
Perhaps your sides are about to split.
Red Giants can’t stay inflated.
They use up all their fuel.
Puffed up and massive.
Suddenly they can pop like a balloon.
Not enough energy to push out,
the star will fall inwards,
In a million years or so?
You might be a Supernova!
Make a Betelguse nebula.
Then Orions shoulder will flower.
And we may see an exploding star.
The first in the Milky-way since 1604.
A Dalek at Froghall a few years ago… That’s another story…
I was reading the New Scientists back page last week and there was a question about time travel. Where would you go to in the past or future? Something along those lines. The answer one person gave is that as the planet moves through space, if you travelled six months forwards or backwards for example, when you rematerialised Earth would be at the other side of its orbit. Difficult unless you are in a vessel with an airlock. They went on to explain that as the sun is also moving through the milky way galaxy, its planets spiral around it in its wake, so where Earth was a year ago is far behind where it is now.
I realised from reading that, that your time machine would have to move in space as well as time. In something like the T. A. R. D. I. S. This is a time machine in the Sci fi series Dr Who. It means “Time and relative dimensions in space”. In other words it can travel in space as well as time.
Considering the show was first broadcast in the 1960’s that’s pretty clever. Working out you need to be able to find the Earth’s coordinates in time and space. Mind you they were closer in time to Einstein so they might have had more of an idea about it than we do…..