First Published:

# How fast?

How long does it take the light to get from the Sun to the Earth?

A:  No time all.  You will hear the answer ‘8 and a half minutes’ but that is from our perspective on Earth.  From the perspective of the light, it takes no time at all!  So it takes the light no time, be we see it as taking over 8 minutes.

Relativity is that all observations are relative to the perspective of the observer.

The point is that time itself is relative to the observer. Acceleration changes the perspective of an observer, so as an observer changes speed, time changes. For perspective to change significantly, you have to be travelling at incredible speed, as the change is determined by your speed as a fraction of the speed of light.  The light itself, in the above example, is actually travelling at infinite speed from the perspective of light.  But relativity means time distorts and any observer not also travelling at the speed of light, will observe the light travelling at the fastest speed anything will appear to be travelling at, the speed of light.

# Yes, you can go faster than 300,000km/s (lightspeed), it just doesn’t look that way to others.

You may read that the approximately 300,000km/s (the speed of light) is the fastest speed there is. In reality this depends on point of view).  You will also read that if you travel fast enough time will pass more slowly and if you travel the over 4 light years to the nearest star fast enough, that although it will still take over 4 years on Earth, only 1 year will pass for you, and fellow travellers.  So you would then have travelled over 4 light years in 1 year of your time. If you divide distance travelled by time you get 4 light years per year- or 4x the speed of light at 1,200,000km/s.  The trap is that, for someone who stayed back on earth, over 4 years will have passed, so they will see you as having travelled only slightly below the speed of light.

But for you, the traveller, it is possible to start accelerating and just keep on accelerating at constant acceleration with everything appearing normal. You could keep accelerating to 1 times speed of light, 2 times, 4 times and even faster.  It is those that do not come for the ride who will see your speed as just getting closer and closer to the speed of light, you never reaching the speed of light.

This is not the deepest analysis, but was produced in response to a specific question.

## Science & Philosophy

### Surprise, Shortest day ever recorded: Not just the solstice, but climate change?

The first ‘fun fact’ is that while everyone knows how the length of daytime and nigh time vary throughout the year, it may come as a surprise to realise the length of the entire day, also varies. Partly because, second fun fact, the a day is a longer than one rotation of the Earth, which lead to the third fun fact: we just had the shortest total day ever recorded.

### Carbon Capture and Storage: When it works, and why it doesn’t for work ‘blue hydrogen’.

There are both vocal supporters and vocal opponents of carbon capture and storage, and there are arguments for both sides. This page goes beyond reporting on how carbon capture and storage fails to make current ‘blue hydrogen’ projects sustainable, and looks at the underlying principle that dictates why carbon capture and storage, despite having genuine valuable applications, can never enable ‘blue hydrogen’ to be environmentally sustainable, but is so popular politically.

### WordPress.com to the Next Level: Plugins, Elementor, CoBlocks?

Something completely different. A discussion on how this site is hosted: on wordpress.com.

Anyone who has started a “blog” or other site on wordpress.com, may get to wonder, what are the options for upgrading the website? What is the value of the free, personal or premium plans and beyond? What real world benefits are there, and, alternatively, what would you lose and/or gain from moving away from wordpress.com. This is a page discussing being in that situation. If you are not considering having a website, it may be of little interest.

### Images, Making Animated GIFs & Solving colour problems.

This is part of series of pages I will be adding on things I have learnt as part of building this website, and I will soon try and enable following by topic (when I get this page working), so people can separately select notification on building websites and/or population or other issues, without being notified of things outside their interest. Standby for that update.

Meanwhile this page provides general help on making an animated GIF for a series of images, specific help on a challenge with animated GIFs, and a list of sites with free images as a resource for those building images.

### Hydrogen Future: Often Scams, Even If Not Intended, So Always Ask “Where does the hydrogen come from?”

In the race to stop CO2, there are many scams involving hydrogen, but are the public or the backers being scammed? There are many myths, and in the end, Hydrogen is a light, but inefficient battery solution. This is an exploration of where Hydrogen may be a solution, and where it just does not add up.