Supernovae: Cosmic Fireworks

A supernova is a spectacular explosion of a massive star. Not very. Astronomers believe that about two or three supernovas occur each century in galaxies like our own Milky Way. Because the universe contains so many galaxies, astronomers observe a few hundred supernovas per year outside our galaxy. Space dust blocks our view of most of the supernovas within the Milky Way.

A supernova is a magnificent, luminous explosion that marks the end of a massive star’s life. These events are relatively rare: only about two or three supernovae occur each century in a galaxy like the Milky Way. Astronomers typically detect only a few hundred supernovae outside our galaxy every year.

Given that the observable universe contains an estimated 2 trillion galaxies, why do astronomers register so few supernovae per year? The reason is that most supernovae occurring in the universe are too faint to be observed. They may be obscured from our view by cosmic dust, or they may be located too far away for present-day telescopes to detect.■

Sources

1. What Is a Supernova? | NASA Science
2. How Many Galaxies Are There? | Space
3. Cosmic census of galaxies updated to 2 trillion | Science News
4. How many galaxies are in the Universe? | BBC Science Focus
5. How Many Galaxies Are There in the Universe? | Sky & Telescope

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• Cover Image: Snapshot of “Supernova with Expanding Shell” by Michael McClare and Dana Berry, Goddard Space Flight Center; available in the NASA Image and Video Library.

Eye-Level Shoponomics

No matter how retailers arrange goods on their shelves—horizontally, vertically, by block, margin, market share, or otherwise—the area at and 15 inches below eye level is always the prime real estate in every aisle of large supermarket chains, department stores, convenience stores, and even small, mom-and-pop shops. This is where brands, usually more expensive goods, are strategically placed—making them the easiest for adult shoppers to browse and reach without stretching or stooping.

The Art of Holding Your Pee

When your bladder fills up, the pressure inside increases, triggering a psychoneural process that leads to urinary urgency—that sudden, compelling need to urinate. Sometimes, fulfilling that immediate need encounters unexpected hurdles: no restroom nearby, all nearby ones are locked, or the distance to the nearest one is too great. Or, you may find yourself in a situation where leaving immediately isn’t an option. What should you do?

Like vs Such as

“Like” and “such as” are often used interchangeably to introduce examples. However, there is a subtle difference in their usage. “Like” is more informal and is used to draw comparisons or to liken one thing to another. “Such as” is more formal and specific, typically used to introduce examples in a list or to specify particular instances.

Pelvic Floor Muscle Training

While using the bathroom to relieve yourself may not seem like exercise, it actually engages your pelvic floor muscles. Without their proper contraction and relaxation, this basic activity would be impossible. These muscles can weaken and strain due to factors such as poor posture, sedentary lifestyle, constipation, chronic coughing, obesity, aging, injury, or pelvic surgery. Pregnancy and childbirth can also have a detrimental effect on their strength. Weak or strained pelvic floor muscles can lead to conditions such as urinary or fecal incontinence, involuntary passage of intestinal gas, pelvic organ prolapse, or sexual dysfunction.

What can you do to strengthen and condition your pelvic floor muscles?

Safely Sneezing and Coughing

By looking up or over your shoulder while coughing or sneezing, you can reduce the strain on your pelvic floor caused by the sudden increase in pressure in your abdomen.

Peeculiar Urinometrics

The human bladder can hold between 350 ml to 600 ml of urine. Its fullness can be comfortably suppressed by voluntary activity of the pudendal nerve until the bladder reaches a maximum capacity of about 500 ml. With a typical fluid intake of around 2 liters per day, healthy adults usually excrete between 800 to 2,000 milliliters of urine daily, making an average of seven trips to the bathroom in a 24-hour period.

Do your urination habits align with these averages?

Chilling Resilience: How Frogs Survive the Cold Winter

Animals have a variety of ways to cope with adverse environmental conditions. Many utilize dormancy—a prolonged period of inactivity and fasting—to survive winters when temperatures often drop below freezing.

Frogs, along with other cold-blooded amphibians, lack the ability to regulate their body temperature internally. Thus, they have developed clever methods to conserve energy when their bodies cool significantly during winter brumation, a process similar to hibernation in mammals.

Clearing the Air: Tree Planting Won’t Solve Air Pollution

Undoubtedly, trees play an important role in reducing air pollution in urban areas. However, their contribution alone is not sufficient. While trees are generally beneficial, they can also have negative effects. In some cases, they hinder the dispersion and transport of air pollutants and may even emit gases that exacerbate air pollution.

Checking In? Check for Bed Bugs First

The last thing you want after returning home from a business trip or vacation is to discover unwelcome guests—bed bugs—that you brought with you. They are found worldwide, from North and South America to Africa, Asia, and Europe, even in unexpected places like five-star hotels and luxury resorts. Therefore, the first thing you should do after checking into a hotel room is to inspect it for bed bugs.