Sunlight reaches Earth in eight minutes but is thousands of years old

Warm rays of sunshine are a welcome sight in the morning. They warm the soil in the garden, help plants make energy through photosynthesis and provide light for solar energy. Earth is at the perfect location in the solar system to benefit from the sun’s life-giving light, heat and energy--approximately 93 million miles from the sun.

Light from the sun isn’t created because the sun is burning like a campfire, but instead because of nuclear fusion. Nuclear fusion is when one proton smashes into another proton so violently that they stick together and release energy in the process.

As a star, the sun is composed of gas--primarily hydrogen and helium. At the sun’s core, nuclear fusion converts hydrogen to helium which generates energy in the form of gamma rays (the highest frequency and shortest wavelength of the electromagnetic spectrum) and heat (the sun’s core temperature is more than 28 million degrees Fahrenheit). Each gamma ray photon has a long journey before it reaches Earth (a photon is a unit of light or electromagnetic radiation). 

The sun is so dense that it takes hundreds of thousands to millions of years for one photon to travel to the surface of the sun, which is no small journey at nearly half a million miles. During that journey, the photon loses so much energy bumping into other photons that it emerges as visible light. The last 93 million miles to Earth is then covered in a flash--only eight minutes. I find it hard to comprehend that the light shining in my window right now may have been created a million years ago by two hydrogen protons smashing into each other. 

The sun’s heat takes longer to reach Earth and doesn’t come from the core. Instead, the heat we receive originates in the corona, part of the sun’s atmosphere that is only visible during a solar eclipse. The corona extends all the way to Earth and beyond, thinning as it goes. Solar winds carry the heat and charged particles from the corona outward into the solar system at an incredible 280 miles per second. These charged particles are the ones that penetrate the Earth’s protective magnetosphere and help create the northern lights. 

Unlike Earth’s atmosphere where the temperature decreases as distance from the surface increases, the sun’s atmosphere actually becomes hotter for a distance. At the sun’s surface (called the photosphere), the temperature is nearly 10,000 degrees Fahrenheit. Above the photosphere is a 1,500-mile-thick band of plasma called the chromosphere that can reach nearly 180,000 degrees Fahrenheit. Beyond the chromosphere is the corona which can reach temperatures of nearly 1.8 million degrees Fahrenheit. These hot temperatures are not because of nuclear fusion like in the sun’s core but instead they are created by gas expansion and magnetic field lines being spliced and releasing energy in the form of heat. 

Partial solar eclipse viewed from Bettles, Alaska on May 20

The sun is a complex system of plasma, magnetic fields and nuclear fusion reactions that can boggle the mind. However, we can enjoy two solar events this summer that have fascinated humankind for centuries--a solar eclipse and the transit of Venus across the sun. The solar eclipse occurred on May 20 when the moon aligned perfectly between Earth and the sun. The transit of Venus will occur on June 5 and this will be the last chance to see this phenomenon in your lifetime--the next one occurs in 2117. Check out Venus’s transit by looking through a welder’s helmet (not for too long) between 3:09 p.m. Pacific Time and sunset. 

Note: Published in the Bonners Ferry Herald on May 31, 2012. 

Look to the sky for your daily weather forecast

One of the first things I do every morning is look outside and see what type of day it’s going to be. I always hope for bluebird days filled with sunshine, but if clouds are present I take a guess at what the day might be like. Will it be overcast or rainy? Does the thin layer of high clouds indicate an incoming storm?

 Cumulus, cirrocumulus and cirrostratus clouds share the sky on a summer afternoon

Clouds show us what is happening in the atmosphere--mainly that warm, moist air is rising, expanding and cooling. Since cool air cannot hold as much water vapor as warm air, some of the vapor condenses onto dust particles in the cooler atmosphere. When billions of these droplets come together in the same area, a cloud is visible.

           

When looking at clouds notice the cloud’s height and appearance. Clouds are broken into three levels: high (above 20,000 feet), medium (6,500 to 20,000 feet) and low (below 6,500 feet). Both high- and mid-level clouds reflect height in their name: high-level cloud names contain “cirro-” and mid-level cloud names contain “alto-”. For example, cirrus clouds are a common high-level cloud that are wispy and feathery in appearance. They indicate fair weather but forewarn that a change will occur within 24 hours.



Cirrus clouds are wispy and feathery and indicate fair weather

Low-level cloud names are based on their appearance instead of height. Either the cloud develops horizontally in a layer (stratus) or it develops vertically (cumulus). Stratus and cumulus clouds are present at all heights and the prefix helps describe where if not at a low-level. For example, altostratus clouds are flat, uniform clouds found at mid-levels. They often form ahead of a storm that will produce continuous rain or snow.

           

Stratus clouds are the clouds that can sock in the Kootenai Valley for days in the winter and produce no precipitation. If the cloud deck thickens and produces steady precipitation, then the clouds are called nimbostratus (“nimbo” meaning precipitation). Both altostratus and stratus clouds can morph into nimbostratus clouds.

           

On the brighter side, cumulus clouds are fair weather clouds. They fill summer skies with puffy, cotton-ball shapes that we lay back and watch. While the weather may be nice, the air is turbulent and anyone flying in an airplane will have a bumpy ride. Cumulus clouds show that there are pockets of warm air rising into the atmosphere.

           

When there is extreme instability in the atmosphere, like on a hot August afternoon, cumulus clouds can become towering cumulus clouds that mature into cumulonimbus clouds. Cumulonimbus clouds, also called thunderheads, have the anvil-shaped top and can produce lightening, thunder, hail, heavy rain and tornadoes. But there needs to be significant heat rising from the ground to produce cumulonimbus clouds, which is why we typically only see them during warmer months. On a summer morning, if the sky is filled with altocumulus clouds (often aligned in rows) watch for thunderstorm activity in the afternoon.



The anvil-shaped top of a cumulonimbus cloud points in the direction the cloud is moving

Not all clouds fit into the cookie-cutter names but by looking at their appearance and height, you can at least guess what the day may be like.

Note: Published in the Bonners Ferry Herald on May 24, 2012.

Dig on in to find out about earthworms

I have never given much thought to worms besides wanting some in my garden and when they are scattered across roads on rainy days. I’ve discovered that worms are incredible creatures despite their simple appearance. They don’t have legs, arms, eyes, ears, teeth or lungs like we do, but they can move and have functioning nervous, circulatory, digestive, excretory, muscular and reproductive systems. 

While our systems are complex, a worm’s systems are primitive--they have to be to fit into a long, rounded body. A worm is basically a tube within a tube. The inner tube is the digestive and excretory system and the outside tube is the muscular system. In between the tubes is a body cavity filled with coelmic fluid that keeps the worm’s shape since it doesn’t have a skeleton. 

Earthworms have no eyes but can sense light.

Did you realize that earthworms have gizzards like chickens and turkeys? With a diet of soil, organic matter, bacteria and fungi, and no teeth to break it into smaller pieces, the gizzard grinds the “food” so nutrients can be absorbed in the intestines. Worms don’t just open their mouth and take a bite of dirt, they push their pharynx (throat) out, grab the organic matter and then pull it back into their mouth. 

They do this all day long as they tunnel their way through dirt. Worms are voracious eaters; they can eat one-third of their body weight every day--that is equivalent to a 150-pound man eating 50 pounds of food a day and not gaining an ounce. With a simple digestive and excretory system, it doesn’t take long for the organic matter to pass through and come out as worm castings that fill the tunnel behind them.

These tunnels help aerate the soil, keep it from becoming compacted, allow water to better penetrate the soil, and transfer nutrients between the surface and deeper soil. Worms are very beneficial to the soil, especially in gardens. 

But any soil won’t do. The soil can’t be too dry, too cold, too hot or too moist--it has to be just right. If it isn’t the worm will either tunnel deeper (up to six-and-a-half feet)or move to better soil if it can find it. These are a few reasons why worms aren’t found in the desert or in areas with permafrost or permanent snow cover. They can tolerate temporary discomforts, like a dry garden in August, by going into estivation (similar to torpor in hummingbirds). Worms estivate by rolling themselves into a ball and then excreting mucus around themselves to form a cocoon. Then they go into a state of suspended animation until the soil becomes moist again.

However, too much water can make them drown. This is why we see them on driveways and roads on rainy days--they don’t want to drown in their tunnels. But other hazards lurk on the surface, like robins, cars and the sun. If the sun comes out and the worm can’t penetrate the surface (like pavement), it will dry out and die. 

Worms cannot see where they are going because they don’t have eyes--they can only sense light. If they are exposed to light for too long (over an hour) they become paralyzed. That is one of the reasons why earthworms are also called nightcrawlers--because they tend to feed above ground at night (in the absence of sunlight and predators) and burrow during the day.

They also don’t have noses or ears but have chemoreceptors near the anterior (front) end that respond to chemicals and they can sense vibrations. 

How do you know which end is the anterior end of the worm when both ends look alike? The thick band (called the clitellum) is near the anterior but is only found on mature earthworms. The clitellum is part of the reproductive system, of which worms are hermaphrodites, meaning they have both male and female reproductive organs. 

The clitellum is not visible on immature earthworms such as this one. 

A worm’s primitive systems do have benefits--they allow the worm to regrow portions of its body if they become severed, perhaps by a shovel. However, a worm cannot perform miracles and if the segment lost is too big or if it loses portions of its anterior end, it won’t be able to grow them back. Worms are fascinating creatures, you just have to dig a little to find out about them. 

Note: Published in the Bonners Ferry Herald on May 17, 2012. 

Ladybugs are a gardner’s friend

Of all places, I did not expect to see dozens of ladybugs milling around on bare rocks amidst the snow on a ridge above Trout Lake in early June. What were ladybugs doing in this snowy landscape miles from the nearest spring greenery? 

Ladybugs soaking in the sunshine after a long winter above Trout Lake

It seems like an odd place for an insect to hibernate but ladybugs commonly overwinter in colonies high in the mountains, especially in rocky areas that become snow-free first. Not all ladybugs have the option to overwinter in the mountains, so they seek out warm, secluded places such as rotting logs, under leaf litter or inside houses. 

The extreme adaptability of ladybugs has allowed them to colonize grasslands, forests, cities, riparian zones and almost anywhere else there is food and tolerable winters. They are found worldwide except for Antarctica, Greenland, and the arctic portions of North America, Europe and Asia. 

Ladybugs are also called ladybirds and lady beetles, even though there are both males and females. The story behind the ladybug’s name is that European farmers once prayed to the Virgin Mary when pests began eating their crops. After insects descended on their crops and ate the pests, the farmers called the helpful insects “beetle of Our Lady”. The name was later shortened to lady beetle and ladybug.

Most of the 5,000 species of ladybugs eat insects and the remaining few eat plants. One of their favorite foods is aphids and that is the reason why gardeners and farmers like them. A single ladybug can eat nearly 5,000 aphids in its lifetime. 

Even though we think of ladybugs as red with black spots, they can also be yellow, orange or black with spots, stripes or no markings at all. The one most familiar to us is the seven-spotted ladybug, with its red-and-black shiny body and white patches on the sides of its black head. The seven spots are divided three on each side and one in the middle. As a ladybug ages, the spots fade.

Seven-spotted ladybug on a fern frond

One might think that the ladybug’s bright coloring would attract predators but the opposite is true--it warns them to stay away. Most predators only have to eat a ladybug once before they associate it with tasting bad. The unappealing taste comes from a foul-tasting fluid the ladybug secretes from its leg joints. Like monarch butterflies, the ladybug’s bright colors advertise its distastefulness to its predators which include birds, frogs, wasps, spiders and dragonflies. 

Even though ladybugs can fly, they often play dead to escape predators. Their wings are not visible but are protected under hardened wing covers (called elytra), which is the red-and-black-spotted part on a seven-spotted ladybug. The elytra and the rest of the ladybug’s exoskeleton are made of the same protein that forms our hair and fingernails. 

Despite the ladybug’s small size, it can pack away enough fat reserves within its exoskeleton to survive nine months of hibernation--whether under leaf litter in the garden or on a mountain. 

Note: Published in the Bonners Ferry Herald on May 10, 2012.

Baby animals can be born helpless or ready to follow mom

From downy ducklings to wobbly moose calves, the animal kingdom is diverse in the ways baby animals come into this world. Some animals are born ready to tackle the world, like mountain goat kids that can keep up with the nannies when only a few hours old even though they are no larger than a snowshoe hare. Other animals are completely helpless, born with their eyes closed and unable to fend for themselves like baby songbirds. 

Juncos are born altricial (totally helpless) 

Baby animals can be described in two ways: precocial and altricial. Precocial young are born with eyes open, able to walk, feed themselves and can keep themselves warm. A few precocial species include ducks, geese, mountain goats, moose and porcupines. Altricial young are born naked, blind, incapable of walking and totally rely on their parents for food and warmth. A few altricial species include bears, coyotes, squirrels and all perching birds. 

Duckling are born precocial (ready to follow mom)

The difference between a rabbit and a hare is based on their young, altricial and precocial respectively. Bunnies are born blind, naked and helpless whereas leverets (baby hares) are born fully furred with eyes open and capable of running soon after birth.

One of the differences between precocial and altricial birds is when they incubate the first egg. Parents of precocial chicks will begin incubating after the entire clutch is laid so all the young hatch at the same time and can leave the nest together. This is commonly seen in ducks, geese and swans, but is also a characteristic of ptarmigan, sandpipers and sandhill cranes. Alternately, altricial birds start incubating after the first egg is laid and the young hatch in succession which creates a nest full of different aged young. 

Goslings follow their parents shortly after hatching (precocial)

Animals that have a protected site can afford to raise helpless young, such as bears. Mother bears give birth to cubs in the protection of their winter den during hibernation. The cubs are born blind and helpless but nurse as the mother bear hibernates. The mother bear will wake up from hibernation to give birth, eat the placenta and clean up her newborns. 

The timing of the cub’s birth is planned to coincide with hibernation, even though the bears mate in the spring. Delayed implantation makes this happen. After they mate in late spring/early summer, the egg is fertilized but is not implanted in the uterus. By mid-summer it will become an early stage embryo but then development is paused until fall. At denning time, the female’s body determines whether or not it has enough fat reserves to carry out development, give birth to and nurse the cubs. If not, the female’s body will absorb the embryo and gain some nourishment in the process. 

Black bear cubs are altricial at birth and stay with their mother for two to three years

Delayed implantation is also found in weasels, wolverines, marten, mink, river otters, badgers and skunks. 

With Mother’s Day approaching, all mothers should be remembered for the hardships of bringing new life into this world, from the mother porcupine who gives birth to a fully-quilled baby porcupine (thankfully the quills are soft!) to our own mothers who raised us from helpless babies to who we are today. Happy Mother’s Day!

Moose calves are precocial at birth so they can escape predators
but their legs are quite wobbly.