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Radio Show & Podcast Feedback / J. Webb telescope: "...next few months cooling down..."

« on: 25/01/2022 04:46:12 »

Re: the "MRSA, The Metaverse & Medical Milestones" podcast. In the report about the James Webb telescope, Matt says: "It's going to be a little while to be honest. So James Webb is going to spend the next few months cooling down to operating temperature and then hopefully, by spring or summer 2022, we'll start to get some nice, pretty pictures back."

Why does an object floating around in space take months to cool down?
Cheers!
PS hope this post isn't in the wrong place!

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Physiology & Medicine / Is that it? Just two suggestions for improving memory?

« on: 10/02/2020 20:05:10 »

Just listened to the episode "Soy, slingshots and Cyanide". This is the second episode I've heard that touches on the subject of memory. In this one, two suggestions were made: better sleep, and more exercise. Is that really it???
Is there no research out there that can suggest anything better?
Anything?
At all?
Pleeeese?
I've got a crap memory and have experimented with memory palaces, "implementation intentions", flash cards and a few others with varying degrees of success. But the one that really works....is Siri. 

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Physics, Astronomy & Cosmology / Can you help me understand "speed"?

« on: 09/11/2019 13:13:18 »

(this is my first post on here so be gentle with me!)
Quoted from latest episode "eggs, eyes etc..., in answer to the question: "How fast a rocket can humans safely travel in?"
"So the Earth rotates at 600 miles an hour. So we're currently on the earth going 600 miles an hour, because we're on the earth we're also going 600 miles an hour. The Earth is speeding around the sun at 70,000 miles per hour. So we are also speeding around the sun at 70,000 miles an hour. The sun is speeding through the galaxy at 450,000 miles an hour, which means we're also spinning at 450,000 miles an hour."

I'm probably dim, but how can I understand "speed" in this statement? Are the references always implicit? For example, in the first statement "we're on earth going 600 mph", should I implicitly understand that the "reference" (if that's even the correct word!) is the centre of the earth, and this jumps to the sun in the second statement "The Earth is speeding around the sun at 70,000 miles per hour". In other words, in astronomy, when speeds are mentioned, should I just assume that I should understand the quoted speed relative to an "obvious" reference.

The reason I'm asking the question is because I simply don't "get" relativity, time dilation etc...e.g. in the classic example of my "twin" charging off in a rocket at near the speed of light aging differently to me, am I not simply "aging" at the same rate relative to my twin, because relative to him/her, I'm charging off in the opposite direction at an equal and opposite speed, therefore cancelling out any warping of time?
Hope that makes (some) sense!