What does it mean that Mercury is retrograde?

One of our patrons heard someone blame their bad luck on Mercury being retrograde. They’d heard the expression before, but had never stopped to think about what it meant.

We found our answer in The Total Skywatcher’s Manual by Linda Shore, David Prosper, and Vivian White, Wonders of the Solar System by Brian Cox, and The Cambridge Encyclopedia of Amateur Astronomy by Michael E. Bakich. Retrograde motion is when a planet appears to move backyard in the sky, going from east to west. (The opposite – the normal, west-to-east movement -- is called prograde motion.) When a planet is  retrograde, it isn’t actually moving backwards. It has to do with that planet’s orbit around the sun relative to Earth’s. When Earth catches up to a planet and overtakes it, the other planet appears to move in the opposite direction, like when a fast car passes a slower one on the highway.

Susan Miller, writing for AstrologyZone.com, explains what astrologists think about Mercury retrograde. Mercury is said to rule communication as well as formal contracts and agreements, and when it is in retrograde, it is in a “resting” state, so problems might arise in those areas. This is why some people don’t like making big decisions or signing contracts during Mercury retrograde periods. However, it’s also said to be a very intuitive period, and a good time to reflect on the past.

According to the 2017 edition of The Old Farmer’s Almanac, Mercury will be retrograde from January 1-9, April 9-May 3, August 13-September 5, and December 3-23 in 2017.

Why do my air plants keep dying?

“I thought air plants were supposed to be low-maintenance, but mine keep dying. What am I doing wrong?”

Tillandsias, commonly known as air plants, are often marketed as needing no care. However, they are still living plants (part of the bromeliad family, which also includes pineapples), and, as such, they need light and water to survive. We have a copy of Air Plants: The Curious World of Tillandsias by Zenaida Sengo, which has good information on tillandsia care and gives some hints about what our patron may have been doing wrong.

Our patron’s plants may not have been getting enough water. Sengo recommends either misting them 3-7 times a week, dunking them in water for a few minutes 2-4 times a week or every 7-10 days, depending on the variety of plant, or submerging them for an hour or two each week. An under-watered plant with begin to brown and crisp up at the tips, or its leaves may curl in on themselves.

However, air plants are also prone to rot, so if they weren’t aired out properly, that may have been what did them in. Sengo recommends shaking the water out of tillandsias, and making sure to place them on top of rocks or branches as opposed to something that retains water like soil or moss. Also, while tillandsias look good in terrariums, gardeners need to be especially careful not to overwater them – air in terrariums doesn’t circulate well, so it takes longer for the plant to dry out.

A tillandsia that isn’t getting enough light may have discolored leaves, or it may show no signs of distress until a thorough watering causes it to abruptly fall apart. While the gardener may think that watering was the cause of death, the lack of light was the real problem, preventing the plant from performing its normal functions. Tillandsias need as much bright, indirect light as possible, and Sengo suggests a few hours of gentle direct sunlight as well, such as the morning light from an east-facing window. 

Why did we domesticate ferrets? What are they for?

It’s generally believed that humans domesticated cats to help us with pest control and dogs to provide protection and help with hunting and herding. One of our patrons has two pet ferrets, and he wanted to know when people began bringing ferrets into their homes, and what purpose they originally served.

We found some information in Ferrets for Dummies by Kim Schilling and Susan A. Brown’s article “History of the Ferret” on weaselwords.com. Today’s pet ferret is assumed to be a domesticated form of either the Western or Eastern European polecat, and they have been in our lives for about 2,500 years. It’s not certain who first tamed them. While some sources say Egypt, citing hieroglyphs depicting weasel-like creatures, Schilling believes that the hieroglyphs were probably depicting native mongooses, which were kept as pets to kill snakes and small rodents. While mongooses look similar to ferrets and weasels, they are not part of the same family. Ferrets, weasels, otters, wolverines, badgers, martens, stoats, and minks are all Mustelids.

Ferrets seem to have been first domesticated for hunting and pest control. Between 63 BC and 24 AD, Caesar Augustus was requested to sail ferrets out to the Balearic Islands where an overpopulation of rabbits was causing a famine. They assisted hunters in catching the rabbits. (The practice of hunting with ferrets, called “ferreting,” involves releasing the ferrets near a burrow. The ferret is not meant to catch the game, just drive it out of its burrow to where the hunter is waiting. The ferrets would often have bells on their collars so that the hunters could keep track of them, and sometimes they would also be tethered.)

Like cats, ferrets were considered very useful on ships for the ability to keep the rodent population down. The Colonial Navy of Massachusetts named the ferret their official mascot in 1986, saying that, in the days of wooden ships, ferrets were even better than cats, as they could fit into all the tiny nooks and crannies where mice tried to hide.

Ferrets were once even used to transport wires and cables through narrow pipes. According to Brown and Schilling, oilmen, telephone companies, camera crews, and sailors have used them in this way. People would tie the wire or cable to the ferret or its harness and the ferret would run through the pipe on its own.

They are still raised for their fur, although this is less common than it once was, and they’re often used in biomedical research. However, most people today know them as companion animals.