Mars News

This week NASA announced that it has discovered evidence that liquid water is flowing on Mars.  Not just in the past as previously announced, but now.

The existence of liquid water on the surface of Mars is rather unexpected. To understand why, look at the following phase diagram chart, showing the states of water as a function of pressure (vertical axis) and temperature (horizontal axis):


On the surface of the Earth, we live at 1 atm. This means that water exists as a solid (“ice”) at a temperature below 0 degrees Celsius, as a liquid (“water”) between 0 and 100 degrees Celsius, and as a gas (“water vapor”) above 100 degrees Celsius. You can see this in the diagram above by following the horizontal dotted line from left to right at P = 1 atm.

Let’s look at Mars.  The atmospheric pressure on the surface of Mars is about 0.006 atm. Look at the chart above.  At an atmospheric pressure of 0.006 atm, liquid water is just on the knife-edge of being able to exist at all. If the pressure were slightly lower than 0.006 atm, water would transition directly from a solid to a gas with an increase in temperature. (An example with which you’re familiar on Earth is carbon dioxide, which transitions directly from a solid  we call “dry ice” to a gas at 1 atm). Slightly higher, liquid water could exist, but only in a very narrow band of temperatures.

Atmospheric pressure and temperatures make the existence of liquid water on Mars an extreme challenge.  At the very least, the above phase diagram shows why finding liquid water on the surface of Mars is very surprising.  Perhaps minerals and salts dissolved in the water shift the phase diagram enough to permit liquid water to exist under a broader range of temperatures. It is certainly worth exploring further, in person.

Speaking of exploring in person, Eric Berger (@chronsciguy) of the Houston Chronicle wrote an article about why it is so hard to get to Mars. Definitely worth reading.

Mars News

August Volatility in the US Stock Market


Driving home the other day, I heard a segment on NPR that was discussing the recent market downturn and its possible causes. Interestingly enough, one of the guests during the segment asserted the following:

“Firstly, the markets are very thin right now because it is August and you have a lot of the seasoned traders away on vacation. You’ve got less volume than anywhere in the markets. And so there’s a long tradition of people overreacting during this vacation season.”

When pressed on this point, the guest analyst didn’t waiver:

“But the reality is that, you know, many of the most seasoned and senior traders tend to go on vacation this time of year. And yes, we can all remain in contact with our iPhones and our iPads and whatever else while we’re on the beaches. But traditionally, you have had a lot of pretty wild market movements in the month of August historically.”

The question of volatility seems to be an easy point to test. First, some assumptions:

  • A market index such as the S&P 500 is an indicator of the broader market performance.
  • Volatility is high if the closing price on a given day is markedly different (up or down) than the closing price on the day prior.
  • A given month is more volatile if it has more high-volatility days than another month.

Based on the assertion that August volatility is caused by junior traders, I infer that with senior traders in charge, there should be less volatility. Otherwise, I claim that the causal relationship between volatility and the seniority of the traders is not provable.

To test the theory, I downloaded the S&P 500 closing prices for the last 10 years and performed some calculations. First, for each day I calculated the change in closing price, and percentage change in closing price. Here is an example:


S&P 500 Closing Price

Change from Previous Day
C(i) = P(i)-P(i-1)

Percentage Change from Previous Day
R(i) = C(i)/P(i-1)



















The variations in the percentage change in closing price, calculated by finding the standard deviation, will provide the measure of market volatility in accordance with the assumptions above.

Using the S&P 500 closing prices for the last 10 years, performing the above calculations, segregating the data into 12 separate monthly bins, and calculating the standard deviations for each monthly bin yields the following:

 Month Standard Deviation Rank
Jan 0.0114 7
Feb 0.0109 8
Mar 0.0128 5
Apr 0.0096 12
May 0.0105 10
Jun 0.0109 9
Jul 0.0100 11
Aug 0.0136 4
Sep 0.0141 3
Oct 0.0191 1
Nov 0.0168 2
Dec 0.0122 6

Based on the daily variations in the S&P 500 closing prices over the last 10 years, it is true that August is one of the more volatile months. However, the variations in August are exceeded by the Fall months – September (#3), November (#2), and October (#1). Therefore, if the “junior varsity” traders being in charge cause volatility in August, what is the explanation for the even higher volatility in the Fall months?

Perhaps the guest analyst had some other measure of volatility in mind – inter-day swings in prices, daily trading volume, or something else I haven’t considered. Based on the volatility in daily closing prices, however, August is in the top half of volatile months, but isn’t as volatile as the Fall months. Therefore, I question the association of August volatility with junior traders. Based on data over the last 10 years, it doesn’t seem to be a viable explanation based on the assumptions above.


Is The Stock Market Volatility A Correction Or A Full-Blown Crisis? August 25, 2015

S&P 500 Historical Data, last updated 2015-08-26 6:51 PM CDT

Image via

August Volatility in the US Stock Market

2, 4, 8


A few weeks ago I ran across a very simple puzzle. It is a rule based on a sequence of three numbers. Some sequences obey the rule – and some do not. The challenge is to guess what the rule is. According to the opening paragraph of the article accompanying the test, the test sheds light on government policy, corporate America and why no one likes to be wrong.

The puzzle starts with the following:

2, 4, 8 – obey the rule.

Then it is up to you to provide other sequences and guess the rule.

Here is the link:

Go ahead.

Give it a try.

I won’t spoil it for you.

Once you’ve given it a try, return here.

I’ll wait.

(Jeopardy music.)

What did you think? Did you guess correctly?

The test explores confirmation bias. Were you willing to search for a “No” answer, or did your couch your guesses to give “Yes” answers? In my case, I started with a specific sequence that gave “Yes’s”: A x B = C, and tried a few others that all led to “Yes” as well.

I wondered: are there any sequences that give “No?”  So, I took a stab until I got a “No.”

The first “No” answer taught me more than all the “Yes’s” I got before. I kept trying to get “No’s.” In the end, I got 5 “Yes’s” and 7 “No’s”, at which time I decided upon an answer: each number in the sequence is greater than the number before it.

The first lesson I took away is that this test applies to more problems than those dealing with numbers.   The basic principle is applicable to many situations we face every day. In the weeks following the test, when I faced a situation and thought I knew the answer, I said to myself, “2, 4, 8.” It’s my self-cue to ask another question.

Another key takeaway: the best questions are those in which I get the opposite of what I was expecting. Such an answer shakes up confirmation bias and tells me something new.

2, 4, 8 – a simple yet powerful test to challenge confirmation bias.

2, 4, 8

Space Can Be Unforgiving


After a string of successes, SpaceX encountered a setback with the failure of SpaceX CRS-7 mission yesterday. For cargo services to the International Space Station, it has been a somewhat unlucky string of missions. First, the Orbital Sciences Corporation Orb-3 cargo mission failed in October 2014, followed by the Russian Progress M-27M in April 2015. This makes three in the last year.

Regarding the SpaceX CRS-7 mission, here are a few links that cover the failure:

  • Marcia Smith of the excellent provides a write-up on the preliminary cause of the CRS-7 failure.
  • Here is NPR ‘s coverage of the failure.
  • Lastly, here is’s detailed write-up on the failure.
Space Can Be Unforgiving

Poking at US Space Policy

Dr. Paul Spudis published two articles in recent days that caught my attention. The first discusses a proposed Chinese mission to the far side of the Moon, and the second discusses the search for life on Mars.

In total, the two are a continuing theme of questioning US space policy, and are a good read. Looking at both in a big-picture sense, one has to wonder why the US is choosing to pass up on developing cislunar space, treating it as nothing more than a proving ground for developing an eventual mission to Mars.

Food for thought.

Poking at US Space Policy

HST at 25

Space enthusiasts everywhere are celebrating the 25th anniversary of the Hubble Space Telescope. And it is with good reason. On this day that marks the 25th anniversary of the landing of Shuttle mission STS-31 that delivered HST to orbit, I wish to share a few thoughts and links that make this anniversary special to me.

A few years ago I reflected on how each of the Shuttle missions associated with HST served as a “signpost” to various stages of my career at NASA.  Those words from the past are just as relevant today.

Reflections of Hubble

Another retrospective is via an interview with Bill Reeves, who served as the Lead Flight Director for Shuttle mission STS-31 that delivered HST to orbit. I had the pleasure of working with Bill in later years before he retired, and his words of reflection on HST illustrate the deeply insightful person that he was at that time, and still is today.

Earthquakes and Compassion: Houston Matters (Bill’s retrospective is from 16:10 to 25:00)

Once Hubble was on orbit, we all knew what happened. Its vision was blurry. The next link recounts the race to save Hubble and its reputation, via an interview with Ed Weiler, who was Hubble Chief Scientist at the time. I later met Ed on two occasions – the first when he was the Associate Administrator of the Office of Space Science at NASA Headquarters, and later when he was the Director of the Goddard Space Flight Center. He’s an interesting fellow with interesting views, some of which are hinted at in this story.

Fixing Hubble’s blurry vision

Perhaps the greatest success of Hubble goes beyond the telescope itself. In one way, HST is the perfect example of the blending of art and science. It is the powerful, insightful images from a scientific standpoint coupled with astonishing beauty that strikes a chord with me. Here are some of HST’s most incredible images.

15 Magnificent Images from the Hubble Telescope

Lastly, in looking outward, HST permits us to look inward. The images of astronauts servicing Hubble on several occasions demonstrate how NASA’s scientific and human endeavors can work together. Beyond that, Hubble has allowed us to learn our place in the universe. For me, the next story brings this to life.

Hubble Telescope Celebrates 25 Years In Space

And so, on this 25th anniversary, I salute the Hubble Space Telescope once again for being a special part of my space life, and the space life of the rest of us. Cheers!

Oh, and wait until you see what’s next

HST at 25

Target Out of Canada


There is a reason why Canada had long been a popular first step in international expansion of American companies, and for Target it was no different. Numerous restaurant chains, such as Baskin Robbins, Burger King, Dairy Queen, Little Caesars, McDonalds, Popeyes, Quiznos and Wendy’s have been active in Canada for years, some since the 1960s. Retailers were also drawn to Canada: Sears arrived in 1953 through a joint venture, and Costco, Home Depot and Walmart arrived through acquisitions in 1986, 1992, and 1994, respectively.  In 2010, more than ten percent of Canadians had shopped Target stores in the United States, and 70 percent of the population was familiar with the Target brand. Therefore, it made sense that Target would be drawn to Canada for its first foray into international expansion.

Target followed the acquisition model established in Canada by Cosco, Home Depot, and Walmart. It purchased the Canadian discount chain Zellers in 2011, and organized Target Canada with headquarters in Mississauga, Ontario. It planned to convert over a hundred of the former Zellers locations into new Target stores. After two years of planning, Target opened its first three stores in Ontario on March 5, 2013. Target rapidly opened stores across Canada over the next 21 months, eventually growing to 133 stores. Yet on January 15, 2015, Target Canada filed for bankruptcy, citing huge losses of over two billion dollars and its inability to meet payroll.

What happened to Target in Canada?

Some news accounts – especially from Canadian sources – blamed differences between the Canadian consumer and the American consumer for Target’s failure. Others blamed Target’s rapid expansion across Canada coupled with its historical shortcomings in supply chain management, along with marketing problems. The problem is that from a strategy standpoint, these are radically different challenges that require completely different strategic treatments. Was Target’s strategy failure in Canada really more of a cultural problem, or an operations management and marketing failure?

To examine the possibility of the former, I’ll broaden the scope beyond cultural concerns and examine the entire CAGE framework, defined by the distance in cultural, administrative, geographic, and economic factors between two countries. A CAGE analysis will tell us whether Target failed to take into account the differences between Canada and the United States in devising its Canadian strategy.

From a geographic standpoint, Canada and the United States share the largest international border in the world, with a length (excluding the Alaskan border) of nearly 4,000 miles. About 75 percent of Canada’s population lives within 100 miles of the border with the United States. The population distribution across Canada somewhat resembles the United States in an east-west sense, with greater densities on the coasts and more scattered population centers in the middle. Therefore, geographic distance between Canada and the United States in the CAGE framework is about as small as it can get; the challenge is one of managing a supply chain that either must address the east-west population distribution within Canada, or manage customs in crossing the border between Canada and the United States. Neither is an unfamiliar strategic problem for any company with supply chain experience.

From an economic standpoint, the cost of labor is generally higher in Canada than in the United States. Minimum wages are higher in Canadian provinces, and the taxation burden is higher. Previous to Target’s entry, the Canadian dollar was weak relative to the US dollar; however, a stronger Canadian dollar and a robust economy following the financial crisis of 2008-09 made the Canadian market very attractive for entry. Supply of real estate is more limited in Canada versus the United States; the number of lenders for retail development is fewer, so access to capital is harder. (This is a reason why many retailers choose to enter through acquisitions–the path chosen by Target in Canada.) Canada’s economy is comprised of regional commercial centers that are far apart, and to some extent, independent of one another. Yet in 2011 sales per square foot in Canadian malls were nearly 50 percent greater than sales per square foot in American malls. Therefore, despite the higher cost of labor and limited real estate market, other economic conditions such as exchange rates and sales per square foot made an entry into Canada very attractive in the early 2010s. (Foreshadowing hint: how Target managed expectations around price differences relative to the different cost structure is a point I’ll discuss later.)

From an administrative standpoint, there are some differences between Canada and the United States in language, labeling and other regulatory requirements. All mandatory labeling information must be in English and French (the official languages of Canada), and measurements must use the metric system. Provincial franchise disclosure laws have a higher requirement for disclosure that can trip up an American company if it is not well versed in those disclosure requirements. Yet Canada follows rule by law just as the United States does. (One of the quaint differences is that lawyers robe in court in Canada, but at least don’t wear wigs.) Although the differences (robes included) can add to costs, none are considered a major impediment to strategy.

Lastly are the cultural differences. Some of Canada’s population hubs are immensely multi-cultural; others are less so. Consumer differences are sometimes driven by the generally colder weather. However, the population distribution and consumer differences are not markedly different than that obtained by taking a northern slice across the United States, and accounting for this difference strategically should have been straightforward for a company founded and headquartered in Minneapolis with a store presence in a similar variety of settings across the United States. Target’s market research prior to its expansion into Canada indicated that customers wanted the “true U.S. Target.” Based on a smart approach to accounting for regional differences and stated consumer preferences, addressing the above cultural differences should not have been an insurmountable strategic problem.

The above CAGE analysis recognizes that Canada does have uniquely Canadian factors. However, none of the CAGE dimensions – cultural, administrative, geographic, and economic – were the key contributing factor to Target’s downfall in Canada. Instead, its downfall was a problem in executing a manageable strategy in operations management, along with a failure in marketing. The company has admitted it botched management of its supply chain with a rapidly expanding store footprint across Canada, which often led to empty shelves. Marketing, long considered Target’s forte, focused too much on conveying the sheen and trendiness of the Target brand. Target took its same “Expect More. Pay Less” tagline to Canada, and it is reasonable the Canadian consumer took that to mean they would expect more and pay less than they did in the United States, now that Target was in Canada!  Target augmented its slogan with “Target Loves Canada”, yet failed to set consumer expectations that because the cost structure is slightly higher in Canada, prices would be, too. These are a failing of operations management and marketing strategies that have nothing to do with the CAGE differences between Canada and the United States.

The bottom line is that Target’s customers in Canada wanted the exact same Target they experienced in the United States, and they didn’t get that.  Target failed in its operations management and marketing strategies in delivering to its Canadian customers. That is why Target in Canada failed.


Austen, I. and Clifford, S. (2012, September 14). American Retailers Face Challenges in Expanding to Canada. Retrieved from

Canada Facts. National Geographic. Retrieved March 20, 2015 from

Evans, P. (2015, January 15). Target closes all 133 stores in Canada, gets creditor protection. Retrieved from

Hanuka, B. (2014, March 5). The Dangerous Mistake U.S. Retailers make in Canada. Retrieved from

Kopun, F. (2013, November 22). Cool Canadian welcome hurts Target’s profits. Retrieved from

Kopun, F. and Sparks, R. (2015, January 15). Target Canada lessons: Six ways not to expand into Canada. Retrieved from

Prentice, B. and Dahlhoff, D. (2015, January 23). Why Target’s Big Canadian Expansion Went South. Retrieved from

Target Canada. Wikipedia. Retrieved March 20, 2015 from

Townsend, M. (2015, January 22). Why Target is Raking Up Its Maple Leaves. Retrieved from

Weinberg, L. (2012, August 10). Why Canada is still the best place for U.S. brands to expand. Retrieved from

Zimmerman, A. and Talley, K. (2011, January 14). Target is Going Abroad – to Canada. Retrieved from

Target Out of Canada