In the geocentric model of how things work, it's really easy for you to fall directly toward Earth. This happens because you are already moving fast enough to have a very small delta vee with the surface at any particular moment. Not so falling into the sun, which is so hard, we only just launched the first probe that can do it on purpose:
The reason has to do with orbital mechanics, the study of how natural forces influence the motions of rockets, satellites, and other space-bound technology. Falling into the sun might seem effortless since the star’s gravity is always tugging at everything in the solar system, including Earth. But Earth—along with all the other planets and their moons—is also orbiting the sun at great speed, which prevents it from succumbing to the sun’s pull.
This arrangement is great if you’d like to avoid falling into the sun yourself, but it’s rather inconvenient if you want to launch something there.
“To get to Mars, you only need to increase slightly your orbital speed. If you need to get to the sun, you basically have to completely slow down your current momentum,” says Yanping Guo, the mission-design and navigation manager for the Parker Solar Probe. Based at the Johns Hopkins Applied Physics Laboratory, Guo has been working on the probe for about 17 years.
Probes bound for deep-space destinations like Mars can piggyback off Earth’s momentum to fly faster. For a spacecraft to launch toward the sun, on the other hand, it must accelerate to nearly match the Earth’s velocity—in the opposite direction. With the planet’s motion essentially canceled out, the spacecraft can surrender to the sun’s gravity and begin to fall toward it. But this is almost impossible with current rocket technology, so spacecraft have to get some help, in the form of slingshot maneuvers off other planets, called gravity assists.
Douglas Adams, therefore, was partially correct: generally speaking, if you throw yourself at the sun, you will miss (and wind up in a stable orbit). NASA has just started the process of hitting it.
The New York City subway, with its passive air exchange system and tunnels too small for active ventilation or air conditioning, have gotten excessively hot this summer:
On Thursday, temperatures inside at least one of the busiest stations reached 40°C—nearly 11°C warmer than the high in Central Park.
The Regional Plan Association, an urban planning think tank for the greater metropolitan area, took a thermometer around the system’s 16 busiest stations, plus a few more for good measure, and shared the data with CityLab. A platform at Union Square Station had the 40°C reading at 1 p.m., which was the hottest they found, although Brooklyn Bridge-City Hall and Columbus Circle weren’t far off at 39°C and 38½°C, at around 10 and 11 a.m., respectively. Twelve out of the 16 busiest stops boiled at or over the 32°C mark in the late morning and early afternoon.
One might think that subway stations would offer crisp respite to sweaty New Yorkers, being underground and all. But you’d be wrong. Heat doesn’t only “rise”—it just diffuses to cooler areas, which can include below-ground spaces. Plus, only a few of the city’s 472 stations are equipped with air conditioning; most rely on a passive ventilation system better known for their Marilyn Monroe moments above ground. This system was built in the days before AC, and the MTA says it’s not possible to squeeze the station-cooling machinery that other metro systems have inside New York’s narrow tunnels. Meanwhile, the units that cool passengers inside cars actually shed heat into the stations as trains pass through.
That onboard air-conditioning can fail, too. The MTA has also seen a rising number of complaints about overheated cars in recent years. In today’s issue of Signal Problems, his indispensable newsletter focused on subway accountability, the journalist Aaron Gordon reports that “about two percent of all subway cars in service on any given day might not have working A/C,” according to the MTA. That means at least 100 cars are roasting passengers on any given day this summer.
This problem also bedevils the London Underground.
Meanwhile, here in Chicago, we're having our 73rd day this year above 27°C, just 10 short of the record. Given the normal number of temperatures that warm between now and October, I think we'll probably set a new one.
And the sunlight here looks eerily orange and hazy today, because of climate change-driven wildfires out west.
Welcome to the future.
Friday evening, a baggage worker at SEATAC airport outside Seattle stole an empty commuter plane and crashed it into an uninhabited part of an island in Puget Sound. Pilot and journalist Jim Fallows has an analysis:
Bizarre, frightening, and tragic this certainly was. Was it a sign of an alarming failure in security practices, and some press accounts immediately asserted? (For instance, from the UK’s Telegraph, soon after the event: “It has raised fundamental questions about airline security at America’s major airports after the mechanic was able to board the plane, taxi onto the runway and take off without being stopped. Aviation experts questioned what the authorities would have been able to do if the pilot was determined to fly the plane into a city rather than do loop-the-loops.”
Maybe this will be the appropriate response when more facts are known. For the moment, as is usually the case with aviation disasters, many of the most important questions about what happened are impossible to answer right away.
I hope that, when the facts are in, the response to this odd, sad incident will resemble what the aviation system usually does with its failures, rather than the way the political system often behaves. That is, I hope it serves as a source of guidance for further threat reduction, rather than as fuel for panic and finger-pointing about the modern realities that some “What if?” will always remain.
What a strange story.
Bruce Schneier says that the TSA's thoughts about security at smaller airports are exactly the conversation they should be having:
Last week, CNN reported that the Transportation Security Administration is considering eliminating security at U.S. airports that fly only smaller planes -- 60 seats or fewer. Passengers connecting to larger planes would clear security at their destinations.
To be clear, the TSA has put forth no concrete proposal. The internal agency working group's report obtained by CNN contains no recommendations. It's nothing more than 20 people examining the potential security risks of the policy change. It's not even new: The TSA considered this back in 2011, and the agency reviews its security policies every year.
We don't know enough to conclude whether this is a good idea, but it shouldn't be dismissed out of hand. We need to evaluate airport security based on concrete costs and benefits, and not continue to implement security theater based on fear. And we should applaud the agency's willingness to explore changes in the screening process.
There is already a tiered system for airport security, varying for both airports and passengers. Many people are enrolled in TSA PreCheck, allowing them to go through checkpoints faster and with less screening. Smaller airports don't have modern screening equipment like full-body scanners or CT baggage screeners, making it impossible for them to detect some plastic explosives. Any would-be terrorist is already able to pick and choose his flight conditions to suit his plot.
And just think, it's only taken 15 years and $45 billion to get here...
I love to travel. So I was surprised to learn, after chasing a hunch, that I haven't been outside the state of Illinois since January 22nd, 194 days ago. I confirmed this with Google Timeline.
The last time I've gone this long without traveling to another state (or country), as far as I can tell, was 3 August 1981 to 5 March 1982, a gap of 214 days. But my family probably went up to Wisconsin at some point during that period, so I can't exactly call that a reliable record. Same with the 213-day gap between 4 January 1979 and 5 August 1979 that's on the record. (These dates come from my mom's journals, which is why I'm not sure they're complete.)
So it's possible that this is the longest time in my entire life that I've gone without crossing a state line. And if I don't leave Illinois before my next scheduled trip on August 31st, that'll be 221 days, and absolutely a lifetime record.
What surprises me even more is that I didn't realize this until yesterday. Weird.
More data has emerged about Amelia Earhart's final days:
Across the world, a 15-year-old girl listening to the radio in St. Petersburg, Fla., transcribed some of the desperate phrases she heard: “waters high,” “water’s knee deep — let me out” and “help us quick.”
A housewife in Toronto heard a shorter message, but it was no less dire: “We have taken in water . . . we can’t hold on much longer.”
That harrowing scene, the International Group for Historic Aircraft Recovery (TIGHAR) believes, was probably one of the final moments of Earhart’s life. The group put forth the theory in a paper that analyzes radio distress calls heard in the days after Earhart disappeared.
Some of Earhart’s final messages were heard by members of the military and others looking for Earhart, Gillespie said. Others caught the attention of people who just happened to be listening to their radios when they stumbled across random pleas for help.
Almost all of those messages were discounted by the U.S. Navy, which concluded that Earhart’s plane went down somewhere in the Pacific Ocean, then sank to the seabed.
[Research director Ric] Gillespie has been trying to debunk that finding for three decades. He believes that Earhart spent her final days on then-uninhabited Gardner Island. She may have been injured, Noonan was probably worse, but the crash wasn’t the end of them.
Gardner Island, now called Nikumaroro, fits the classic description of a desert island: it's a small atoll with trees and a very long swim to the next nearest land mass. Crashing there might have meant a slow death from dehydration instead of a quick one from impact. We'll never know for sure, but this new data, if accurate, adds some weight to the hypothesis that Earhart crashed on Nikumaroro in 1937.
As I write this, my Ancestral Homeland's football team are up 1-0 over Croatia in the World Cup semifinals. This wasn't supposed to happen:
Since 2006, England’s performance on the world stage has been lamentable, a comedy of errors marked by group-stage evictions, racism scandals, and grifters. In 2016, after the abrupt departures of two successive managers, the former England player and manager of its feeder under-21 team Gareth Southgate was given temporary charge of the national team, a decision that seemed safe, if uninspired. Expectations for Russia 2018 were muted, to say the least. “Before the tournament started, I could not make a case for us winning it,” the former England captain Alan Shearer wrote, Eeyore-ishly, in a column for the BBC. “I just wanted to see some signs of improvement.”
What happened instead has been a surprisingly smooth path to Wednesday night’s semifinal against Croatia, as a youthful and undaunted England side swept away a nation’s pessimism. Southgate’s great accomplishment—aside from the manager’s natty collection of waistcoats—has been getting the squad to envision itself as a team, as opposed to a collection of surly prima donnas who’d rather be spending their summers on Roman Abramovich’s yacht. England has one of the youngest and most inexperienced squads of all the teams competing in Russia, with an average age of 26.
As England heads toward its Wednesday-night match with Croatia, the anticipation of a potential victory (and a spot in the finals for the first time in 52 years) offers some welcome relief from the turbulence surrounding Theresa May’s government and the ongoing gloom of Brexit. (Almost as perturbing as the England team’s current run of success is the fact that Sunday marked England’s 50th straight day of sunshine.) Waistcoat sales are cresting. Motorways and shopping malls are being abandoned. Even Southgate is daring to dream. “How far can we go?” he told The Guardian.“Let’s push the boundaries, let’s create our own history.”
We've got the match on in the office. Updates as conditions warrant.
I didn't have a chance to read these yesterday:
Now I'm off to work. The heat wave of the last few days has finally broken!
Governor Jerry Brown approved AB 807, which would put to the voters in November an initiative to go to "year round Daylight Saving Time:"
Wrote Brown in a signing message: "Fiat Lux!" (Let there be light.)
Assemblyman Kansen Chu, D-San Jose, who authored Assembly Bill 807, has called the practice of changing clocks twice a year, in the fall and the spring, "outdated." He argues altering the time by an hour has adverse health affects, increasing chances for heart attacks, workplace injuries and traffic accidents.
The ballot measure would overturn a 1949 voter-approved initiative called the Daylight Savings Time Act, which established Standard Pacific Time in California.
Should voters approve the ballot measure, the Legislature would then decide how the state's time should be set. Congress would have to sign off on Chu's main goal of establishing year-round daylight saving time.
If it passes, L.A. and San Francisco would see sunrises at 7:44 and 8:09, respectively. But sunsets would be 17:44 and 17:51. So...if you live in California, how would you vote?
This past weekend included the Chicago Gay Pride Parade and helping a friend prepare for hosing a brunch beforehand. Blogging fell a bit on the priority list.
Meanwhile, here are some of the things I'm reading today:
Back to debugging service bus queues...