Credit: Me :D

Research and software development:

meteors and space objects


Daniel Kastinen

Credit: Me :D

Research and software development:

meteors and space objects

Outline

  1. Introduction
  2. Short overview of the research
  3. Why learn software development

Credit: Me :D

Who am I?

  • Living in Kiruna since 2017
  • Finished PhD Nov. 2022
    From Meteors to Space Safety: Dynamical Models and Radar Measurements of Space Objects
  • Became permanent scientist 2023
  • Task: Conduct research on meteors and space objects!

Who am I?

  • LTU-Rymdteknik 2011->2016
  • Living in Kiruna since 2017
  • Finished PhD Nov. 2022
    From Meteors to Space Safety: Dynamical Models and Radar Measurements of Space Objects
  • Became permanent scientist 2023
  • Task: Conduct research on meteors and space objects!

Solar Terrestrial and Atmospheric Research

Meteors and space objects

  • Meteors, meteoroids, dust
  • Space debris
  • Asteroids and comets
  • Solar system dynamics
  • Mesosphere and Lower Thermosphere

Solar Terrestrial and Atmospheric Research

Meteors and space objects

  • Meteors, meteoroids, dust
  • Space debris
  • Asteroids and comets
  • Solar system dynamics
  • Mesosphere and Lower Thermosphere
  1. Let's start from the beginning...
  • Meteors
  • Meteoroids and meteorites
  • The formation of the solar system
  • Asteroids and comets
  • Meteor showers
  • Meteors

The focus of today

Meteor = the phenomena in the atmosphere

Commonly called "shooting stars"

(video from our new meteor camera in Kiruna!)

Video: Kiruna IRF AllSky7 meteor camera

  • Meteors

Stunning visuals!

  • Meteors

Stunning visuals!

Credit: Nathan Myhrvold

  • Meteors

Stunning visuals!

A spectacle of nature, available to us every clear and dark night

  • Meteors

So, what are they?

  1. Let's start from the beginning...
  • Meteors
  • Meteoroids and meteorites
  • The formation of the solar system
  • Asteroids and comets
  • Meteor showers
  • Meteoroids and meteorites
  • Meteoroids and meteorites

Meteoroid (kinda)

Credit: NASA
Johnson Space Center

Meteor

Photo: Torbjörn Lövgren

Meteorite

Credit: SVT

  • Meteoroids and meteorites

Many different kinds of meteorites!

  • Meteoroids and meteorites

So, where do they come from?

  1. Let's start from the beginning...
  • Meteors
  • Meteoroids and meteorites
  • The formation of the solar system
  • Asteroids and comets
  • Meteor showers
  • The formation of the solar system

Credit: Seung-Hoon Cha and Sergei Nayakshin

  • Hot disk of gas
  • Bodies form, from asteroids to planets
  • Sun ignites! Blows extra gas and dust away
  • Also small particles spiral into the sun
  • Asteroids and comets remain
  • The formation of the solar system

So how do we keep seeing small meteors?

    Sources of meteoroids

  • Comets
  • Asteroid collisions
  • Catastrophic disruptions
  • Impact ejecta
  • Interstellar particles?
  • ...

Larger meteors (bolides/superbolides) are actually asteroids!

  1. Let's start from the beginning...
  • Meteors
  • Meteoroids and meteorites
  • The formation of the solar system
  • Asteroids and comets
  • Meteor showers
  • Asteroids and comets

Credit: NASA/JPL

  • Asteroids and comets

Credit: NASA/JPL

  • We now know where all the big ones are
  • Sometimes a small one ends up on collision course with Earth
  • Then this can happen
  • Asteroids and comets

Video: Chelyabinsk superbolide - Dash-cam footage February 15th 2013

  • Asteroids and comets

Video: Chelyabinsk superbolide - Dash-cam footage February 15th 2013

    Popova, O. P. et al. (2013)

  • ~13 million kg
  • ~19.8 $\pm$ 4.6 meter diameter
  • -27.3 $\pm$ 0.5 magnitude
    (Sun is around -26.7)
  • ~19.16 $\pm$ 0.15 km/s
  • Asteroids and comets

But we also have the smaller events

So how small can they be?

  • Asteroids and comets

So small, they are invisible to the naked eye and cameras

Video: EISCAT radar in Kiruna, Credit: EISCAT

  • Asteroids and comets

So small, they are invisible to the naked eye and cameras

Video: EISCAT radar in Kiruna, Credit: EISCAT

Down to micro-grams, after that its more dust than meteoroids

  • Asteroids and comets

These mostly come from comets while they pass close to the Sun

Credit: Chris Pietsch/The Register-Guard, Comet NEOWISE

  • Asteroids and comets

Dust and meteoroids gets "blown into space"

Rosetta OSIRIS - 67P/Churyumov-Gerasimenko

  • Asteroids and comets

This creates a meteoroid "stream" in space

One that can intersect with Earth

  1. Let's start from the beginning...
  • Meteors
  • Meteoroids and meteorites
  • The formation of the solar system
  • Asteroids and comets
  • Meteor showers
  • Meteor showers

Credit: www.meteorshowers.org

  • Meteor showers

If a long time passes, they spread out and become "sporadic" (random)

  • Meteor showers

If a long time passes, they spread out and become "sporadic" (random)

  • Meteor showers

If a long time passes, they spread out and become "sporadic" (random)

These are usually the ones we can see every night

An overview

Observing meteors

Some of the system we use

AllSky7

EISCAT 3D

Next generation system!

EISCAT 3D

Photo: EISCAT

My work:
connecting the small and big pictures

My work:
connecting the small and big pictures

  • Radar data analysis & signal processing
  • Meteoroid and small body dynamical simulations
  • Statistical methods and solving inverse problems
  • Meteor phenomena and meteoroid stream formation modelling
  • (now also) Optical data processing and hardware
  • ...and space debris (for another time!)

This is a WHOLE lot of software development

So my tip is:

Most of you will need to write code at some point:

if so, master your tool!

But first!...
Lets upgrade our hello world to calculate $\pi$ instead

But first!...
Lets upgrade our hello world to calculate $\pi$ instead

  • Probability is
    $\mathbb{P}(\bar{x} \in A) = \int_{A} f_X(\bar{x})\mathrm{d}\bar{x}$
    where $\bar{x} \sim X$
  • Uniform 2d random distribution on $S = [-1, 1] \times [-1, 1]$
    $f_\mathcal{U}(x, y) = \mathbf{1}_S(x, y) \frac{1}{\text{Area}} = \mathbf{1}_S(x, y)\frac{1}{4}$
  • What is $\mathbb{P}(\sqrt{x^2 + y^2} \leq 1)$?
  • $= \int_{\text{Circle}} \mathbf{1}_S(x, y)\frac{1}{4} \mathrm{d}\bar{x} = \frac{1}{4} A_{\text{Circle}} = \frac{\pi}{4}$
$$\mathbb{P}(\sqrt{x^2 + y^2} \leq 1) = \frac{\pi}{4}$$ $$ \lim_{\mapsto \infty} 4\frac{\# \text{number of points in circle}}{\# \text{number of points}} \mapsto \pi $$ 
                                import numpy as np

samples = 100
x = np.random.rand(samples)*2 - 1
y = np.random.rand(samples)*2 - 1
                            
                                r = np.sqrt(x**2 + y**2)
pi = 4*np.sum(r < 1)/samples

print(f"{samples=} gives {pi=} (error {np.pi - pi})")

Try samples = 1_000_000

The course motivation

First some distinctions

  • Programming

    using a language to solve "problems"

  • Software development

    choosing what "problems" to solve and how to solve them for a greater goal

For example: Build a calculator

The course motivation

For example: Build a calculator

  • Problem 1: capture user input
  • Problem 2: parse input
  • Problem 3: perform computations
  • Problem 4: display/store result

It is vital to learn both programming and software development

The course motivation

      Ron Evans on The Changelog podcast, 2024-05-03

      We're cognition athletes. Don't athletes usually get a trainer? Instead we get a coffee and a donut and the product needs to ship next week.

      replace: product -> data/paper/simulation/...

      So hence the course and some training!

      The course motivation

          Lars Wirzenius - "40 years of programming"

          Interesting and significant software is beyond the capacity of any one person to build alone in a reasonable time frame. This means that the fundamental, crucial, core skills in building software are communication and collaboration.

          The course motivation

          • Learning collaboration
          • Practicing communication

            Lars Wirzenius - "40 years of programming"

            Even in the projects where I'm the only person, there are at least three people involved: past me, present me, and future me. Past me is a lazy and careless slob who always leaves a mess. Present me does superb work, but has to cope with all the stupid stuff done by past me, and needs to placate future me. Future me is an egotistic and opinionated snob for whom nothing is ever good enough.

            The course motivation

            • Learning collaboration
            • Practicing communication
            • Improving your past, present, and future self

              Monya Baker - "1,500 scientists lift the lid on reproducibility"

              More than 70% of researchers have tried and failed to reproduce another scientist's experiments, and more than half have failed to reproduce their own experiments.

              The course motivation

              • Learning collaboration
              • Practicing communication
              • Improving your past, present, and future self
              • Research ethics and reproducibility

                Just based on what was already said

                The course motivation

                • Learning collaboration
                • Practicing communication
                • Improving your past, present, and future self
                • Research ethics and reproducibility
                • Less useless re-inventing the wheel
                • Longevity and maintainability

                Would you rather contribute to

                or

                The course motivation

                • Learning collaboration
                • Practicing communication
                • Improving your past, present, and future self
                • Research ethics and reproducibility
                • Less useless re-inventing the wheel
                • Longevity and maintainability
                • Opens up for collaboration

                The course motivation

                • Learning collaboration
                • Practicing communication
                • Improving your past, present, and future self
                • Research ethics and reproducibility
                • Less useless re-inventing the wheel
                • Longevity and maintainability
                • Opens up for collaboration
                • Implmentation speed and reliability

                Be able to tackle any problem

                Hone your craft. Be an expert at your tools. Train and practice. "Yeah I could do that"

                The course motivation

                This is a very fine line to walk

                  Left side

                • You never get anything done
                • Projects seem too big to even start
                • Nobody benefits from your code

                The course motivation

                This is a very fine line to walk

                  Right side

                • Nobody, including you, knows if or how your code works
                • You are slowed down by your own code
                • Nobody benefits from your code

                The course motivation

                This is a very fine line to walk

                  Middle

                • You refine the critical parts - they can be trusted and maintained
                • You are accelerated by your code
                • Other benefit from your code

                Know thy self

                • Who are you writing code for?
                • Why are you writing the code?
                • When will the code be used?
                • What will it be used for?

                You don't master something by just doing it:
                thinking needs to be involved!

                That's enough rambling for now

                Thank you for attending!