What Does “SPF” Mean?

The SPF on sunscreen stands for sun protection factor, a relative measurement for the amount of time the sunscreen will protect you from ultraviolet (UV) rays. UVB rays primarily affect the outer layer of the skin, the epidermis. They are responsible for sunburns and some surface-level skin cancers. The sun also emits UVA rays, which can penetrate into the lower level of the skin, called the dermis. UVA rays are typically associated with “tanning.” However, the darker color of the skin is a sign of damage to cells in the dermis. SPF numbers typically refer only to UVB rays, but some sunscreens can protect against UVA as well.

How does the SPF tell you how long you’re protected for? Well, let’s say you typically burn after being outside for 30 minutes and have an SPF 15 sunscreen you plan to use. You’d multiply 30 by the SPF, in this case 15. That means that you’re technically protected for 450 minutes, or 7.5 hours—do note that this is technically speaking. Most sunscreens will wear off long before then from exposure to the elements as well as improper application. It is recommended that you reapply every two hours. The number of UVB rays you’re protected from also increases with SPF, though marginally. SPF 15 blocks 93% of UVB rays, SPF 30 blocks 97%, and SPF 100 blocks 99%.

 

What’s the Difference Between Hispanic and Latino?

Latin America, extending from the deserts of northern Mexico to the icy wilds of Tierra del Fuego in Chile and Argentina, encompasses many diverse countries and peoples. Though most of these countries are largely Catholic and Spanish-speaking, thanks to a shared history of colonization by Spain, they have at least as many differences as they do similarities with each other. In the United States the terms "Hispanic" and "Latino" (or "Latina" for a woman; sometimes written as “Latinx” to be gender-neutral) were adopted in an attempt to loosely group immigrants and their descendants who hail from this part of the world. The terms are often used interchangeably, though the words can convey slightly different connotations. It is important to clarify that the categories refer only to a person's origin and ancestry. A Latino/a or Hispanic person can be any race or color.

In general, "Latino" is understood as shorthand for the Spanish word latinoamericano (or the Portuguese latino-americano) and refers to (almost) anyone born in or with ancestors from Latin America and living in the U.S., including Brazilians. "Latino" does not include speakers of Romance languages from Europe, such as Italians or Spaniards, and some people have (tenuously) argued that it excludes Spanish speakers from the Caribbean. Although people from French Guiana are sometimes accepted as Latino since French shares linguistic roots with Spanish and Portuguese, there is much debate about whether people from English-speaking Belize and Guyana and Dutch-speaking Suriname truly fit under the category since their cultures and histories are so distinct.

"Hispanic" is generally accepted as a narrower term that includes people only from Spanish-speaking Latin America, including those countries/territories of the Caribbean or from Spain itself. With this understanding, a Brazilian could be Latino and non-Hispanic, a Spaniard could be Hispanic and non-Latino, and a Colombian could use both terms. However, this is also an imperfect categorization, as there are many indigenous peoples from Spanish-speaking countries who do not identify with Spanish culture and do not speak the dominant language.

 

Why Do We Carve Pumpkins at Halloween?

In Ireland, people started to carve demonic faces out of turnips to frighten away Jack’s wandering soul. When Irish immigrants moved to the U.S., they began carving jack-o’-lanterns from pumpkins, as these were native to the region.

The jack-o’-lantern has a long history with Halloween, although our favorite demonic faces haven’t always been carved out of pumpkins.

Their origin comes from an Irish myth about Stingy Jack, who tricked the Devil for his own monetary gain. When Jack died, God didn’t allow him into heaven, and the Devil didn’t let him into hell, so Jack was sentenced to roam the earth for eternity.

But how did jack-o’-lanterns become associated with Halloween? Halloween is based on the Celtic festival Samhain, a celebration in ancient Britain and Ireland that marked the end of summer and the beginning of the new year on November 1. It was believed that during Samhain the souls of those who had died that year traveled to the otherworld and that other souls would return to visit their homes.

 

Why Do Bananas Turn Brown?

When a fruit comes into contact with ethylene gas, the acids in the fruit start to break down, it becomes softer, and the green chlorophyll pigments are broken up and replaced—in the case of bananas, with a yellow hue.