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This is where I jot down things as I learn them. Some entries are big realisations, some are just little facts that stuck with me. I started keeping it properly when I began my Science Quest project. Newest entries are at the top.
📝 33 entries so far · still adding
I tried reading the summary of a real magnetar paper today. About half the words went over my head, but I looked up "spin-down" and "magnetic dipole" and slowly it started making sense. Reading hard things and not giving up might be the most useful skill I'm building.
Mood: determined.
Finally understood this: a magnetar's huge magnetic field acts like a brake, so even though it's born spinning super fast, it slows to one turn every few seconds. The thing that makes it powerful also slows it down. I added this to the magnetars page.
Learned that in 2020 a magnetar in our own galaxy let out a fast radio burst. Before that, FRBs were a total mystery only seen from far away. So magnetars might explain at least some of them. Real science updating in real time is so cool.
Spent the weekend coding the quiz page in JavaScript. Getting it to mark answers and keep score was tricky - I had a bug where every answer showed as correct. Turned out I was comparing the wrong variables. Fixed it!
Mood: proud (and a bit tired of debugging).
GRBs are the brightest explosions in the universe. Long ones come from giant stars collapsing, short ones from neutron stars merging. A magnetar giant flare can look like a short GRB from far away, which is wild.
Read about SGR 1806-20. A magnetar 50,000 light-years away flared and still managed to mess with the top of Earth's atmosphere. In a fraction of a second it put out more energy than the Sun does in thousands of years. How is that even real.
Mood: jaw on the floor.
Magnetars can have "starquakes" where the crust cracks and releases a burst of gamma rays. The idea of a quake on a star made of neutrons is so strange and brilliant.
These used to be thought of as two different things, but now scientists think they're both just magnetars behaving differently. I like when science tidies up and realises two mysteries are actually one.
A magnetar's field is about 10^15 gauss. Earth's is about 0.5. I made a comparison chart for the website because the numbers are too big to just say out loud. A fridge magnet is around 100 gauss for comparison.
Only around 30 confirmed in our galaxy. They only stay strongly active for maybe 10,000 years, which is nothing in space time, so lots of old quiet ones might be hiding out there.
Decided the magnetar section should be the biggest on the site since it's what my project was about. Made a list of every subtopic I want to cover. It's long.
Discovered you can draw shapes with SVG right in the HTML, no image files needed. I redrew my star diagrams as code so they stay sharp on any screen. This feels like a superpower.
Mood: nerdy joy.
A pulsar is a spinning neutron star with beams of radio waves. As it spins the beam sweeps past Earth and we see a pulse, like a lighthouse. The first one was found in 1967 by Jocelyn Bell Burnell when she was a student. That detail made me happy.
Today I learned that neutron stars can contain more mass than our Sun while being only around 20 km across. A teaspoon of the stuff would weigh about a billion tonnes. It is hard to imagine something so dense.
Mood: brain slightly melted.
So when a big star dies, gravity crushes the core so hard that protons and electrons get squeezed together into neutrons. That's why it's called a neutron star. The whole thing is basically one giant atomic nucleus.
Massive stars fuse elements heavier and heavier until they hit iron. Fusing iron takes energy instead of releasing it, so the core can't support itself any more and collapses. Iron is the dead end. Never thought I'd find a single element so dramatic.
Heavy elements like gold and silver are made in supernovae and neutron star collisions. So the gold in a ring was forged in an explosion across the galaxy. I keep telling my family this fact.
The core of a massive star collapses in less than a second and rebounds in an explosion that can briefly outshine a whole galaxy. In 1054 AD people recorded one bright enough to see in daytime for weeks.
In about 5 billion years the Sun will swell into a red giant and might swallow Mercury and Venus. Then it gently puffs its layers off and becomes a white dwarf. A calm ending compared to the big stars.
A white dwarf is the leftover core, about the size of Earth, slowly cooling for billions of years. It does no more fusion. Eventually (longer than the universe has existed so far) it would fade to a black dwarf.
They've got nothing to do with planets! Old astronomers just thought the round glowing shells looked like planets through their telescopes, and the name stuck. Science is full of these little history quirks.
Once a star starts fusing hydrogen into helium it's on the "main sequence" and stays stable for ages. The Sun has been here 4.6 billion years with about 5 billion to go. Bigger stars burn hotter and die way faster.
That's how much hydrogen the Sun fuses every second. It's been doing it for billions of years. The scale of a single ordinary star is already ridiculous.
Mood: cannot compute.
Before fusion switches on, the collapsing ball of gas is a protostar - hot from squeezing but not a real star yet. I like thinking of it as a star getting ready to be born.
Stars are born inside giant clouds of gas and dust called nebulae. When part of a cloud gets dense enough, gravity pulls it together and a star starts forming. The Orion Nebula is one you can actually see with binoculars, with brand new stars inside it.
Big realisation today: how a star dies is basically decided when it's born, by how much mass it has. Light stars end quietly as white dwarfs. Heavy ones explode and become neutron stars or black holes. One number decides the whole story.
Mood: things clicking into place.
Because light takes time to travel, looking far away means looking into the past. Andromeda's light is 2.5 million years old by the time it reaches us. We literally cannot see the universe as it is "now".
Learned about parallax - hold up your thumb, blink each eye, and it jumps. Astronomers measure the tiny jump of nearby stars as Earth orbits the Sun and use it to work out distances. So clever and so simple.
A light-year is a distance, not a time - how far light goes in a year (about 9.5 trillion km). I kept mixing this up but now it's stuck. Kilometres are just useless for space.
The calcium in my bones and iron in my blood were made inside stars that died before the Sun was born. This one sentence is the reason I wanted to learn everything about how stars work.
Mood: a bit emotional, honestly.
My Science Quest magnetar project went really well and I didn't want all that research to just sit in a folder. So I'm going to teach myself enough HTML and CSS to put it online and keep adding to it. Day one!
Mood: excited and slightly clueless.
Clear sky, no Moon. Found Orion easily and spotted the fuzzy patch that's the Orion Nebula. Hard to believe stars are being born in that little smudge right now. This is what got me hooked all over again.
Starting this journal. I want to remember what it felt like to learn each thing for the first time. Space makes me feel tiny and amazed at the same time, and I think that's a good way to feel.