Happy Friday, everyone.
At the beginning of the week, we looked at the launch and deployment of the new James Webb telescope. If you recall, one of the key elements of the satellite’s design is its sunshield. As the name says, it shields the satellite from the sun, thus keeping the equipment super cold, which is necessary to operate in the range of infrared.
But, as xkcd points out, that’s not actually the real reason for the sunshield.
Credit for the piece goes to Randall Munroe.
Those who know me know one of my pet peeves are when maps of the United States do not display Alaska and Hawaii. I even noted yesterday that those two states were so late of additions to the United States and it made sense as to why they were not included.
So when I was going through some old photos yesterday, I stumbled across this of a poster on the Philadelphia subway system. I had flagged it for posting, but I guess I never did.
I understand this is an advert and so for creative purposes, creative liberty. And it could be that this service does not exist in either Alaska or Hawaii.
But, the statement here is that Metro covers 99% of the United States. Geographically, to do so Metro must cover Alaska because in terms of land area, Alaska comprises nearly 18% of the entire United States. Yeah, Alaska is big. Now, if you’re talking covering 99% of the people of the United States, Metro has some wiggle room. Combined, both Alaska and Hawaii comprise 0.6% of the United States population. That would still leave 0.4% of the American population not covered, and by definition that must be some part of the contiguous lower 48. But above we can see the whole map is purple.
In other words, this is not an accurate map. They should have found some way of incorporating Alaska and Hawaii.
Credit for the piece goes to Metro’s designer or design agency.
Taking a break from going through the old articles and things I’ve saved, let’s turn to a an article from the Washington Post published earlier this week. As the title indicates, the Post’s article explores slaveholders in Congress. Many of us know that the vast majority of antebellum presidents at one point or another owned slaves. (Washington and Jefferson being the two most commonly cited in recent years.) But what about the other branches of government?
The article is a fascinating read about the prevalence of slaveholders in the legislative branch. For our purposes it uses a series of bar charts and maps to illustrate its point. Now, the piece isn’t truly interactive as it’s more of the scrolling narrative, but at several points in American history the article pauses to show the number of slaveholders in office during a particular Congress. The screenshot below is from the 1807 Congress.
That year is an interesting choice, not mentioned explicitly in the article, because the United States Constitution prohibited Congress from passing limits on the slave trade prior to 1808. But in 1807 Congress passed a law that banned the slave trade from 1 January 1808, the first day legally permitted by the Constitution.
Graphic-wise, we have a set of bar charts representing the percentage and then a choropleth map showing each state’s number of slaveholders in Congress. As we will see in a moment, the map here is a bit too small to work. Can you really see Delaware, Rhode Island, and (to a lesser extent) New Jersey? Additionally, because of the continuous gradient it can be difficult to distinguish just how many slaveholders were present in each state. I wonder if a series of bins would have been more effective.
The decision to use actual numbers intrigues me as well. Ohio, for example, has few slaveholders in Congress based upon the map. But as a newly organised state, Ohio had only two senators and one congressman. That’s a small actual, but 33% of its congressional delegation.
Overall though, the general pervasiveness of slaveholders warrants the use of a map to show geographic distribution was not limited to just the south.
Later on we have what I think is the best graphic of the article, a box map showing each state’s slaveholders over time.
Within each state we can see the general trend, including the legacy of the Civil War and Reconstruction. The use of a light background allows white to represent pre-statehood periods for each state. And of course some states, notably Alaska and Hawaii, joined the United States well after this period.
But I also want to address one potential issue with the methodology of the article. One that it does briefly address, albeit tangentially. This data set looks at all people who at one point or another in their life held slaves. First, contextually, in the early years of the republic slavery was not uncommon throughout the world. Though by the aforementioned year of 1807 the institution appeared on its way out in the West. Sadly the cotton gin revolutionised the South’s cotton industry and reinvigorated the economic impetus for slavery. There after slavery boomed. The banning of the slave trade shortly thereafter introduced scarcity into the slave market and then the South’s “peculiar institution” truly took root. That cotton boom may well explain how the initial decline in the prevalence of slaveholders in the first few Congresses reversed itself and then held steady through the early decades of the 19th century.
And that initial decline before a hardening of support for slavery is what I want to address. The data here looks only at people who at one point in their life held slaves. It’s not an accurate representation of current slaveholders in Congress at the time they served. It’s a subtle but important distinction. The most obvious result of this is how after the 1860s the graphics show members of Congress as slaveholders when this was not the case. They had in the past held slaves.
That is not to say that some of those members were reluctant and, in all likelihood, would have preferred to have kept their slaves. And therefore those numbers are important to understand. But it undermines the count of people who eventually came to realise the error of their ways. The article addresses this briefly, recounting several anecdotes of people who later in life became abolitionists. I wonder though whether these people should count in this graphic as—so far as we can tell—their personal views changed so substantially to be hardened against slavery.
I would be very curious to see these charts remade with a data set that accounts for contemporary ownership of slaves represented in Congress.
Regardless of the methodology issue, this is still a fascinating and important read.
Credit for the piece goes to Adrian Blanco, Leo Dominguez, and Julie Zuazmer Weil.
Philadelphia made the national and international news last week, although for once not because we’re all being shot to death. This time because a fire in a rowhome killed 12 people, including nine children. The Philadelphia Inquirer quickly posted a short article explaining what occurred that morning. But the early indication, based upon the confession of a five-year old, is that a child playing with a light set a live Christmas tree on fire.
Ironically, the city prohibits live trees in high rises, apartment buildings, and multi-family dwellings. The rule is in place because live trees are a very real fire hazard. Just a few weeks earlier, a man and two of his sons were killed in a suburb north of Philadelphia (his wife and a third son survived). They died in a fire that began with lights on a live tree. But here in the city, the code states that multi-family dwellings begin at three households. This rowhome had been converted into two separate units, so a live tree was legal. But they would have been better without.
The Inquirer article features a scrolling illustration depicting what we presently know about the fire: how and where it started, why it may have spread, and ultimately who died.
Credit for the piece goes to Sam Morris.
We’re back after a nice holiday break. And one of the most fascinating things to happen was the successful—and seemingly easy, more on that in a bit—launch of the James Webb space telescope. The James Webb was developed by NASA with contributions from both the European Space Agency (ESA) and the Canadian Space Agency (CSA). Whilst it did launch behind schedule and at a price tag of $10 billion, the James Webb is the most sophisticated and complex space telescope mankind has yet launched into space. It will look backwards into time to some of the earliest stars and galaxies in the universe. It will also look at the thousands of exoplanets we have discovered in the last three decades. The instruments aboard James Webb will be able to help us identify if any of these planets have water and other ingredients necessary for life as we know it. This could be one of the most monumental space missions yet.
But James Webb’s launch was far from guaranteed. As this great article from the BBC explains, the construction, assembly, launch, and deployment were all incredibly complicated. James Webb is expected to operate for ten years before its fuel, needed to keep the telescope cold, runs out. However, the seemingly easy launch and deployment means that it used less fuel than expected. Some early reports suggest that the telescope may have some additional time left in it now before the fuel runs dry.
I encourage you to read the article, because it explains the advantages of the telescope, how it works, and its deployment with several illustrations. There are five in particular, though I’ll share only two screenshots.
The most important is this, the key distinction between Hubble and James Webb. It shows how the two space telescopes will be operating in different parts of the electromagnetic spectrum.
The graphic fakes the colours, because by definition we can only see the visible portions of the spectrum. Wavelengths get either too short or too long on either side of the visible spectrum—which differs for different species. I would actually really enjoy seeing how these two spectra stack up against other space observatories like Chandra (x-ray) and Spitzer (infrared).
Next we have the deployment, which finished just last week. The graphic summarises how complicated this process was—and how fraught with risk. But in the end it went off without any major hitch.
This uses a nice series of small multiples of illustrations. These simplified drawings show how the tightly packed telescope unfolds and then begins deploying its vital heat shield then its mirror.
The last thing to check out in the article is a slider showing the “before” and “after”. You have seen them before for things like flood or hurricane damages. Here, however, you can compare a photo in Hubble’s visible light to an existing infrared version of the same photo.
Of course, just because the telescope finished deploying its mirror last week doesn’t mean we get photos this week. The Baltimore-based team running the observatory will spend the next few months tuning everything up. But the goal is hopefully to have the first images from James Webb sometime in June.
And then we have the next ten years to hopefully start collecting data.
Credit for the piece goes to the BBC graphics team.
Well, my week is over and whilst I may publish a post here and there the rest of the month, please do not expect it. My holiday time is truly here and I’ll be away for the next two and a half weeks. Fear not, for like McArthur to the Philippines I shall return. But in 2022.
But before I step away for a much-needed break, I encourage you to never read the comments section with this sadly brilliant piece by Jessica Hagy of Indexed.
Credit for the piece goes to Jessica Hagy.
Last month the Washington Post published a nice article that detailed the deep water cooling system that the city of Toronto, Canada uses to keep itself cool. For the unfamiliar, deep water cooling at its simplest means sucking up very cold water from the bottom of a lake or ocean or wherever you can get very cold water, and then pumping that inland to absorb heat before cycling it back.
Of course, for the longer explanation—and what makes Toronto’s system different—you should read the article. And for our purposes it includes some nice illustrations that diagram just how that system works. The screenshot below captures the basic process I just described, but there are additional illustrations that do a great job showing just how the system works.
What I particularly enjoy about this style is how the illustrations of the building and similar are minimal and restrained. This allows the diagrammatic elements to come to the forefront, which is important to make the system understood.
Credit for the piece goes to Daisy Chung.
Many of us know the debt that comes along with undergraduate degrees. Some of you may still be paying yours down. But what about graduate degrees? A recent article from the Wall Street Journal examined the discrepancies between debt incurred in 2015–16 and the income earned two years later.
The designers used dot plots for their comparisons, which narratively reveal themselves through a scrolling story. The author focuses on the differences between the University of Southern California and California State University, Long Beach. This screenshot captures the differences between the two in both debt and income.
Some simple colour choices guide the reader through the article and their consistent use makes it easy for the reader to visually compare the schools.
From a content standpoint, these two series, income and debt, can be combined to create an income to debt ratio. Simply put, does the degree pay for itself?
What’s really nice from a personal standpoint is that the end of the article features an exploratory tool that allows the user to search the data set for schools of interest. More than just that, they don’t limit that tool to just graduate degrees. You can search for undergraduate degrees.
Below the dot plot you also have a table that provides the exact data points, instead of cluttering up the visual design with that level of information. And when you search for a specific school through the filtering mechanism, you can see that school highlighted in the dot plot and brought to the top of the table.
Fortunately my alma mater is included in the data set.
Unfortunately you can see that the data suggests that graduates with design and applied arts degrees earn less (as a median) than they spend to obtain the degree. That’s not ideal.
Overall this was a really nice, solid piece. And probably speaks to the discussions we need to have more broadly about post-secondary education in the United States. But that’s for another post.
Credit for the piece goes to James Benedict, Andrea Fuller, and Lindsay Huth.
Where is my mind? On the dark side of the humour scale. Because when I saw this latest Venn diagram from Indexed, my mind leapt somewhere else entirely.
At the end of the day, don’t talk to strangers, kids.
Credit for the piece goes to Jessica Hagy.
Winter is coming? Winter is here. At least meteorologically speaking, because winter in that definition lasts from December through February. But winters in Philadelphia can be a bit scattershot in terms of their weather. Yesterday the temperature hit 19ºC before a cold front passed through and knocked the overnight low down to 2ºC. A warm autumn or spring day to just above freezing in the span of a few hours.
But when we look more broadly, we can see that winters range just that much as well. And look the Philadelphia Inquirer did. Their article this morning looked at historical temperatures and snowfall and whilst I won’t share all the graphics, it used a number of dot plots to highlight the temperature ranges both in winter and yearly.
The screenshot above focuses attention on the range in January and July and you can see how the range between the minimum and maximum is greater in the winter than in the summer. Philadelphia may have days with summer temperatures in the winter, but we don’t have winter temperatures in summer. And I say that’s unfair. But c’est la vie.
Design wise there are a couple of things going on here that we should mention. The most obvious is the blue background. I don’t love it. Presently the blue dots that represent colder temperatures begin to recede into and blend into the background, especially around that 50ºF mark. If the background were white or even a light grey, we would be able to clearly see the full range of the temperatures without the optical illusion of a separation that occurs in those January temperature observations.
Less visible here is the snowfall. If you look just above the red dots representing the range of July temperatures, you can see a little white dot near the top of the screenshot. The article has a snowfall effect with little white dots “falling” down the page. I understand how the snowfall fits with the story about winter in Philadelphia. Whilst the snowfall is light enough to not be too distracting, I personally feel it’s a bit too cute for a piece that is data-driven.
The snowfall is also an odd choice because, as the article points out, Philadelphia winters do feature snowfall, but that on days when precipitation falls, snow accounts for less than 1/3 of those days with rain and wintry mixes accounting for the vast majority.
Overall, I really like the piece as it dives into the meteorological data and tries to accurately paint a portrait of winters in Philadelphia.
And of course the article points out that the trend is pointing to even warmer winters due to climate change.
Credit for the piece goes to Aseem Shukla and Sam Morris.
