---
title: "Meteorite Mass Distribution and Uncertainty"
subtitle: "Observed falls show less uncertainty than found meteorites across all classes"
description: "An exploration of uncertainty in extraterrestrial meteorite mass measurements, comparing observed meteorite falls versus those found later. This visualization reveals how discovery conditions impact measurement precision across different meteorite classes."
date: "2025-04-29"
categories: ["30DayChartChallenge", "2025"]
tags: [
"meteorites", "uncertainty", "extraterrestrial", "ggdist", "halfeye plot", "confidence intervals", "statistical uncertainty", "celestial objects", "space rocks", "astronomy"
]
image: "thumbnails/30dcc_2025_29.png"
format:
html:
toc: true
toc-depth: 5
code-link: true
code-fold: true
code-tools: true
code-summary: "Show code"
editor_options:
chunk_output_type: inline
execute:
freeze: true
cache: true
error: false
message: false
warning: false
eval: true
# filters:
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# share:
# permalink: "https://stevenponce.netlify.app/data_visualizations/30DayChartChallenge/2025/30dcc_2025_29.html"
# description: "Day 29 of #30DayChartChallenge: Uncertainties & Extraterrestrial. Visualizing how discovery methods affect measurement uncertainty in meteorite masses."
# twitter: true
# linkedin: true
# email: true
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---
{#fig-1}
### <mark> **Steps to Create this Graphic** </mark>
#### 1. Load Packages & Setup
```{r}
#| label: load
#| warning: false
#| message: false
#| results: "hide"
## 1. LOAD PACKAGES & SETUP ----
suppressPackageStartupMessages({
pacman::p_load(
tidyverse, # Easily Install and Load the 'Tidyverse'
ggtext, # Improved Text Rendering Support for 'ggplot2'
showtext, # Using Fonts More Easily in R Graphs
janitor, # Simple Tools for Examining and Cleaning Dirty Data
skimr, # Compact and Flexible Summaries of Data
scales, # Scale Functions for Visualization
lubridate, # Make Dealing with Dates a Little Easier
ggdist, # Visualizations of Distributions and Uncertainty
camcorder # Record Your Plot History
)
})
### |- figure size ----
gg_record(
dir = here::here("temp_plots"),
device = "png",
width = 8,
height = 8,
units = "in",
dpi = 320
)
# Source utility functions
suppressMessages(source(here::here("R/utils/fonts.R")))
source(here::here("R/utils/social_icons.R"))
source(here::here("R/utils/image_utils.R"))
source(here::here("R/themes/base_theme.R"))
```
#### 2. Read in the Data
```{r}
#| label: read
#| include: true
#| eval: true
#| warning: false
meteorite_landings <- read_csv(
here::here(
"data/30DayChartChallenge/2025/Meteorite_Landings_20240731.csv")) |>
clean_names()
```
#### 3. Examine the Data
```{r}
#| label: examine
#| include: true
#| eval: true
#| results: 'hide'
#| warning: false
glimpse(meteorite_landings)
skim(meteorite_landings)
```
#### 4. Tidy Data
```{r}
#| label: tidy
#| warning: false
### |- Tidy ----
meteorites <- meteorite_landings |>
mutate(
fall = if_else(tolower(fall) == "fell", "Observed Fall", "Found Later"),
mass_g = as.numeric(mass_g),
year = as.numeric(year),
class_simplified = case_when(
str_detect(recclass, "^H") ~ "H Chondrite",
str_detect(recclass, "^L") ~ "L Chondrite",
str_detect(recclass, "^LL") ~ "LL Chondrite",
str_detect(recclass, "Iron") ~ "Iron",
str_detect(recclass, "Pallasite") ~ "Pallasite",
TRUE ~ "Other"
)
) |>
filter(
!is.na(mass_g) & !is.na(year) & !is.na(recclass),
class_simplified %in% c("H Chondrite", "L Chondrite", "Iron", "Pallasite"),
mass_g >= 10 & mass_g <= 100000
)
# Class statistics
class_stats <- meteorites |>
group_by(class_simplified) |>
summarize(
median_mass = median(mass_g),
count = n(),
.groups = "drop"
) |>
arrange(desc(median_mass))
# Reorder class factor levels based on median mass
meteorites <- meteorites |>
mutate(
class_simplified = factor(
class_simplified,
levels = class_stats$class_simplified)
)
```
#### 5. Visualization Parameters
```{r}
#| label: params
#| include: true
#| warning: false
### |- plot aesthetics ----
colors <- get_theme_colors(
palette = c(
"Observed Fall" = "#593C8F", "Found Later" = "#1B9AAA", "Other" = 'gray'
)
)
### |- titles and caption ----
# text
title_text <- str_glue("Meteorite Mass Distribution and Uncertainty")
subtitle_text <- str_glue("Observed falls show less uncertainty than found meteorites across all classes")
caption_text <- create_dcc_caption(
dcc_year = 2025,
dcc_day = 29,
source_text = "Meteorite Landings. University of Rochester"
)
### |- fonts ----
setup_fonts()
fonts <- get_font_families()
### |- plot theme ----
# Start with base theme
base_theme <- create_base_theme(colors)
# Add weekly-specific theme elements
weekly_theme <- extend_weekly_theme(
base_theme,
theme(
# Text styling
plot.title = element_text(face = "bold", family = fonts$title, size = rel(1.14), margin = margin(b = 10)),
plot.subtitle = element_text(family = fonts$subtitle, color = colors$text, size = rel(0.78), margin = margin(b = 20)),
# Legend
legend.position = "bottom",
# Axis elements
axis.text = element_text(color = colors$text, size = rel(0.7)),
axis.title.y = element_text(color = colors$text, size = rel(0.8),
hjust = 0.5, margin = margin(r = 10)),
axis.title.x = element_text(color = colors$text, size = rel(0.8),
hjust = 0.5, margin = margin(t = 10)),
axis.line.x = element_line(color = "gray50", linewidth = .2),
# Grid elements
panel.grid.minor.x = element_blank(),
panel.grid.minor.y = element_blank(),
panel.grid.major.y = element_line(color = "gray65", linewidth = 0.05),
panel.grid.major.x = element_line(color = "gray65", linewidth = 0.05),
# Plot margins
plot.margin = margin(t = 10, r = 20, b = 10, l = 20),
)
)
# Set theme
theme_set(weekly_theme)
```
#### 6. Plot
```{r}
#| label: plot
#| warning: false
### |- Plot ----
p <- ggplot(meteorites, aes(x = class_simplified, y = mass_g, fill = fall)) +
# Geoms
stat_halfeye(
aes(fill = fall),
.width = c(0.50, 0.80, 0.95),
interval_alpha = 0.8,
slab_alpha = 0.7,
point_alpha = 1.0,
scale = 0.8,
position = position_dodge(width = 0.6),
color = "black"
) +
# Scales
scale_y_log10(
labels = function(x) paste0(x / 1000, " kg"),
breaks = c(10, 100, 1000, 10000, 100000)
) +
scale_fill_manual(
values = colors$palette,
name = "Discovery Type"
) +
scale_x_discrete(
labels = function(x) {
counts <- class_stats$count[match(x, class_stats$class_simplified)]
paste0(x, "\n(n= ", scales::comma(counts), ")")
}
) +
coord_flip() +
# Labs
labs(
title = title_text,
subtitle = subtitle_text,
caption = caption_text,
x = NULL,
y = "Mass (kilograms, log scale)"
) +
# Theme
theme(
plot.title = element_text(
size = rel(1.9),
family = fonts$title,
face = "bold",
color = colors$title,
margin = margin(t = 5, b = 5)
),
plot.subtitle = element_markdown(
size = rel(0.85),
family = fonts$subtitle,
color = colors$subtitle,
lineheight = 0.8,
margin = margin(t = 5, b = 20)
),
plot.caption = element_markdown(
size = rel(0.6),
family = fonts$caption,
color = colors$caption,
lineheight = 0.65,
hjust = 0.5,
halign = 0.5,
margin = margin(t = 10, b = 5)
),
)
```
#### 7. Save
```{r}
#| label: save
#| warning: false
### |- plot image ----
save_plot(
p,
type = "30daychartchallenge",
year = 2025,
day = 29,
width = 8,
height = 8
)
```
#### 8. Session Info
::: {.callout-tip collapse="true"}
##### Expand for Session Info
```{r, echo = FALSE}
#| eval: true
#| warning: false
sessionInfo()
```
:::
#### 9. GitHub Repository
::: {.callout-tip collapse="true"}
##### Expand for GitHub Repo
The complete code for this analysis is available in [`30dcc_2025_29.qmd`](https://github.com/poncest/personal-website/blob/master/data_visualizations/TidyTuesday/2025/30dcc_2025_29.qmd).
For the full repository, [click here](https://github.com/poncest/personal-website/).
:::
#### 10. References
::: {.callout-tip collapse="true"}
##### Expand for References
1. Data Sources:
- Pandit, Aabha; Romanowski, Alois; Owen, Heather (2024). [Meteorite Landings. University of Rochester.](https://doi.org/10.60593/ur.d.26462452.v1)
:::