Recently in space Category

Linklist: May 22, 2012

NYT: Big Data Troves Stay Forbidden:

" In the future, he said, the conference should not accept papers from authors who did not make their data public. He was greeted by applause from the audience.

In February, Dr. Huberman had published a letter in the journal Nature warning that privately held data was threatening the very basis of scientific research. 'If another set of data does not validate results obtained with private data,' he asked, 'how do we know if it is because they are not universal or the authors made a mistake?'"

In the "be careful what you wish for department" ... NYT: George Lucas's Plans in Marin:

"But after spending years and millions of dollars, Mr. Lucas abruptly canceled plans recently for the third, and most likely last, major expansion, citing community opposition. An emotional statement posted online said Lucasfilm would build instead in a place 'that sees us as a creative asset, not as an evil empire.'

If the announcement took Marin by surprise, it was nothing compared with what came next. Mr. Lucas said he would sell the land to a developer to bring 'low income housing' here."

TOLLROADSnews: Traffic congestion dropped off 30% in 2011 INRIX says - weak economy, higher gas prices :

"2011 saw a dramatic drop in traffic congestion in the US - 30% fewer hours wasted in congested traffic according to INRIX, the nation's leading provider of traffic data. The 2011 improvement is only outmatched in the years since INRIX has been measuring congestion by the financial crisis year of 2008, when congestion dropped 34%. In 2009 congestion was up 1% and 2010 saw a 10% regrowth of congestion. "

[I call 'Bullshit'. There may have been a methodological problem they are calling a trend.]

Wired: SpaceX In Orbit - Successful Launch of Falcon 9 Rocket :

"CAPE CANAVERAL, Florida — The second time’s the charm for SpaceX. This morning at 3:44 a.m. EDT the company’s Falcon 9 rocket lifted off Launch Complex 40 at Cape Canaveral. After a faulty valve led to an aborted launch on Saturday, today’s successful flight marks the third of the Falcon 9 rocket, the second flight of the Dragon capsule, and the first flight for a commercial spacecraft bound for the International Space Station (ISS)."

Kottke: Douche parking: "I can't tell if the app featured in this video is imaginary or not, but it's a great theoretical solution to the problem of douche parking. Douche parking is basically parking like a douche, and is way more prevalent in Russia than in the US. The Village feels publicly shaming is the best way to deal with douches. Unfortunately, one trait of douches is an inability to be shamed."

Matt Kahn @ Environmental and Urban Economics: New UCLA Research Suggests that Men Should Not Bike:

"A study by researchers at the UCLA School of Nursing has found that serious male cyclists may experience hormonal imbalances that could affect their reproductive health. "

Linklist: April 16, 2012

Elon Musk to Jon Stewart: sustainable energy easier than making life "multi-planetary"

[But we won't switch quirky to sustainable energy, if such a thing really exists, so we really need to keep the off-planet option open]

San Jose Mercury News: Deal cut to give Menlo Park millions of dollars in exchange for Facebook expansion:

"To get Menlo Park's approval of its expansion plan, Facebook has agreed to pay the city millions of dollars in the coming years, seed a community fund with a $500,000 donation, sponsor internship and job training programs, support efforts to boost local businesses, back affordable housing and improve bike and pedestrian pathways. Those and other commitments are outlined in a proposed development agreement released by the city late Thursday. "While Facebook's obligations under the DA (development agreement) will be considerable, they build upon the most significant aspect of Facebook's move -- its commitment to building a stronger community and being a good neighbor," John Tenanes, Facebook's director of global real estate, wrote in a letter accompanying the term sheet."

[Social networks and infrastructure networks meet again]

Rohit T. Aggarwala discusses infrastructure: Fiscal Games Can’t Hide True Cost of U.S. Roads- Bloomberg:

"Chicago’s approach will probably bear some fruit because local governments face many problems of timing. A city government doesn’t have the cash to make building retrofits that will lower its energy bills, but future savings can pay back the loan and then some. A water utility whose rates are set to break even has expensive leaks, but no general-revenue bonding authority to fix them. A highway department wants to extend a toll road, but its capital budget is constrained. These are all problems that finance can solve because investment can unlock future revenue that can be shared with a lender.

Unfortunately, America’s most dire infrastructure problems are not like this. Most of them are like Pennsylvania’s 6,000 structurally deficient bridges. Replacing these won’t create new value, serve new traffic or generate new economic development, so financing has to come from existing income. And that’s a problem not of timing, but of wealth. Even if a replacement bridge can be financed through an infrastructure bank, the debt service on the loan has to be paid back with existing wealth."

[He says "replacing these won't create new value". Not replacing these (the default option) destroys value, so replacing them creates value that would otherwise not be there were they not created. The market may naively think these are permanent, but closing a few of these would quickly disabuse of it that notion. I think the author confuses income and wealth. If I have a steady stream of income, and I don't spend all of it, my wealth increases. The debt service would be paid by future income, not existing wealth, unless you have somehow speculatively capitalized income you don't already have.

As he notes, an infrastructure bank could be backed up by tolls on the new replacement bridges (really, it could, Washington State has put tolls on existing bridges to help build new ones), or gas tax revenue if politicians are too chicken to do that, or value capture on nearby landowners whose access would be maintained. I agree with the general point that user fees are preferred. ]

A really cool map of globalPopulation Density

Linklist: March 13, 2012

Arnold Kling reviews: Matt Yglesias on Urban Development

KurzweilAI finds this potential use for high-speed rail: Startram — maglev train to low earth orbit

Linklist: September 7, 2011

TPM Idea Lab: The World's Smallest Electric Motor Is Made From a Single Molecule "As for uses--oh, yeah, there are actual uses for this thing!--scientists believe that this molecule could further be developed into a motor to power nano-sized devices in fields such as medicine." [Very very small cars]

TPM Muckraker: Wis. Official To DMV Employees: Don't Offer People Free Voter-ID Cards Unless They Ask [An unrecognized role of DMV, and transportation agencies, is establishing identity, and who gets to vote]

KurzweilAI: NASA needs strategic plan to manage orbital debris efforts [See Quark (TV series)]

Mail Online: Phase one of world's first commercial spaceport is now 90 per cent completed - in time for first flights in 2013 [Space will soon be a regular mode, just like maritime and biking (should NASA be part of USDOT?), but I would hate to see space commercialization derailed by orbital debris.]

Layer 8: Air Force awards $25K to inventor of insanely fast device that stops fleeing cars [It goes 130 MPH]

Lisa reviews our paper at Sustainable Cities and Transport: Levinson and Xie on First Mover Advantages in Networks

New GIS toolbox for network analysis: Urban Network Analysis

PoliceBox


Figure 1-2 Transportation Experience

The speed of travel is increasing over time. While we might argue about the rate at which speed is increasing, this long term observation is consistent with improving transportation technology.

Suppose we model technological progress so that the speed of travel is increasing with a compound interest model

V_t = V_{t-1}*\alpha

Where \alpha > 1. (E.g. if speed were increasing at 1 percent compounded annually, alpha would be 1.01).

Escape velocity at the surface of the earth is 11.2 km/s.

According to Wikipedia "[Robert H.] Goddard and his team launched 34 rockets between 1926 and 1941, achieving altitudes as high as 2.6 km (1.62 miles) and speeds as high as 885 km/h (550 mph)." (246 m/s).

In 1959, A Rocket by the Soviets hit the moon at 7,500 mph (3,352.8 m / s). It traveled 236,875 miles in about 35 hours, for an average speed of 3,025.5 m / s.

In 2006, an Atlas V rocket launched toward Pluto is traveling at 36,000 MPH (16,093.44 m / s), taking 9 years (including a Jupiter slingshot).

Proxima Centauri is 4.2 light years (~ 4.0 × 10^13 kilometers) from Earth, or 270,000 times more distant than the Sun.

If we are currently able to travel at 16,000 m/s it would take 2.5x 10^12 seconds to reach Alpha Centauri (about 79000 years).

However, we have maximum speed growing at a compound rate of about 3.39 percent annually (rising from 3,025 in 1959 to 16,093 in 2006). (\alpha ~ 1.0339) (In fact the rate was higher from Goddard to the Russians, and so may be dropping over time, but let's assume this rate is fixed).

So we want to be able travel to Proxima Centauri in less than 79000 years, if we can maintain this rate of speed growth for 100 years, our speed would be 448,718 m/s, but if we wait 1000 years, our speed would be 4,815,654,367,278,682,000 m/s. Since the speed of light = 299,792,458 m / s, that is our upper limit (if we believe Einstein rather than Roddenberry). It turns out, that at 3.39 percent annual compound increase in speed, we reach a maximum speed of 298,736,235 m/s in 295 years from 2006, or the year 2301, and reach the speed of light exactly shortly thereafter (Tuesday afternoon, 5:53 pm).

Hence, we should leave for the stars in 2301 to minimize travel time, reach them in 2305, and try to avoid destroying the Earth and/or Solar System before then. That will get us there far sooner than trying to leave much earlier.

We could leave as early as 2240 and arrive in 2275, but if we wait until 2251, we still arrive in 2275. We save travel time each year we wait after that, but will arrive a bit later.

Scientists propose one-way trips to Mars to jump-start new era of humans in space

By NICHOLAS K. GERANIOS , Associated Press Last update: November 15, 2010 - 9:01 AM

PULLMAN, Wash. - Invoking the spirit of "Star Trek" in a scholarly article entitled "To Boldly Go," two scientists contend human travel to Mars could happen much more quickly and cheaply if the missions are made one-way. They argue that it would be little different from early settlers to North America, who left Europe with little expectation of return.

...

"humans must begin colonizing another planet as a hedge against a catastrophe on Earth."

Finally some clear thinking on space exploration. The point isn't science (which is wonderful, but not cost effective, we can do better science with the resources), or exploration for the sake of exploration (which is wonderful, but really should be done with private money), but one of risk aversion in case we or someone (Vogons) or something else (giant meteorites, solar flares, etc.) screws up the earth.

David Levinson

Network Reliability in Practice

Evolving Transportation Networks

Place and Plexus

The Transportation Experience

Access to Destinations

Assessing the Benefits and Costs of Intelligent Transportation Systems

Financing Transportation Networks

View David Levinson's profile on LinkedIn

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