Peter Rabbit Sledging

Snuggly boy and his favorite toy.

Video by Marielle Tepe

jfam_bc Spiny Lobster Linuparus vancouverensis from the Upper Cretaceous (Upper Campanian - Lower Santonian, Haslam formation) of Chemainus River, Vancouver Island, British Columbia, 🇨🇦. I still remember how I found this lobster over 22 years ago. It was in the middle of the river where I picked up the loose concretion. I gave it one hit with my hammer and exposed the best Linuparus that I have ever found to this date. Simply an amazing feeling.

hannah__dawn 🐉

ロックマン２ / Mega Man2

The concept of information as viewed in theoretical physics through statistical mechanics and thermodynamics, and its implications and connections with evolutionary biology. An interesting reading:

How Life (and Death) Spring From Disorder (via WIRED -original story from Quanta Magazine)

Biological systems don’t defy physical laws, of course—but neither do they seem to be predicted by them. In contrast, they are goal-directed: survive and reproduce. We can say that they have a purpose—or what philosophers have traditionally called a teleology—that guides their behavior.

By the same token, physics now lets us predict, starting from the state of the universe a billionth of a second after the Big Bang, what it looks like today. But no one imagines that the appearance of the first primitive cells on Earth led predictably to the human race. Laws do not, it seems, dictate the course of evolution.

–

David Kaplan explains how the law of increasing entropy could drive random bits of matter into the stable, orderly structures of life.

Cute animals ♥

that is so sad alexa play ozar midrashim

Offering a showy Large Curled with eyes at base, on matrix, Phacops Spine Trilobite. From Mt. Issimour, Morocco, 350 million years 2.4 inch wide fossil only by 2 inches. Overall 3 inches tall by 2.5 inch wide. Shows all around, excellent coloration and professional prep. No spines missing.

www.etsy.com/shop/GoldenHourMinerals

http://stores.ebay.com/Golden-Hour-Fossil-and-Minerals www.goldenhourminerals.com

In 2015, a 777-200 made the Newyork-London route in 5 hours,16 minutes where the usual journey time is ~7 hours.

The flight reached ground speeds of up to 1200 km/h (745 mph),riding a powerful jet stream of up to 322 km/h (200 mph) tailwinds and breaking the sonic barrier ( 1224 km/h (761 mph)).

Tail and headwinds

The principle is analogous to those high school problems in relative velocity:

“A man rows a boat in a river. The velocity of the boat is … Find the stream velocity”

If you are headed downstream i.e in the same direction as the river stream you will reach your destination faster than if you were rowing upstream.

Similarly a tailwind is one that blows along the same direction of the aircraft increasing the net speed of the aircraft ,and headwind is one that blows in the opposite direction and slows the craft down.

So, does this mean that if you are moving at v kmph and there is a headwind of -v kmph, you would just hover? Hell yeah!

Take a look at this video:

Wind shear

A phenomenon known as ‘wind shear’ occurs when the wind speed changes abruptly, which can cause turbulence and rapid increase/decrease in velocity of flight.

This can be really challenging during landing since if the headwind turns tailwind, there is a possibility of the aircraft overshooting the runway due to the increased velocity.

What causes this ?

The aviation industry takes advantage of trade winds and jet streams in order to cut time off the flight and save fuel.

Tradewinds are caused by the unequal heating of the atmosphere at different latitudes and altitudes and by the effects of the Earth’s rotation (Coriolis effect).

                           Trade wind pattern. Credit: Earth Wind Map

Jet streams on the other hand are this narrow current of fast moving winds in the upper troposphere flowing west to east. And riding one can definitely make your travel time shorter.

                               Jet streams in the northern hemisphere

As a result of jet streams, within North America  the time needed to fly east across the continent can be decreased by about 30 minutes if an airplane can fly with the jet stream, or increased by more than that amount if it must fly west against it.

How do pilots know about this ?

Pilots receive a weather briefing actively during flight. Included in the briefing is the best combination of jetstreams and other wind patterns that the pilot can take advantage of saving time and fuel.

Many airports have runways facing in different directions in order to allow the pilots to use the runway that faces the wind during take off/landing.

Have a great day!