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marino5856

Why are there 24 hours in a day? › Ask an Expert (ABC Science) - 0 views

www.abc.net.au/...3364432.htm

day hours

shared by marino5856 on 31 Oct 14 - No Cached
  • "The origin of our time system of 24 hours in a day with each hour subdivided into 60 minutes and then 60 seconds is complex and interesting," says Dr Nick Lomb, consultant curator of astronomy, from the Sydney Observatory.
  • Our 24-hour day comes from the ancient Egyptians who divided day-time into 10 hours they measured with devices such as shadow clocks, and added a twilight hour at the beginning and another one at the end of the day-time, says Lomb.
  • "Night-time was divided in 12 hours, based on the observations of stars. The Egyptians had a system of 36 star groups called 'decans' — chosen so that on any night one decan rose 40 minutes after the previous one.
    • marino5856
      marino5856 on 04 Nov 14
       
      The 24 hours has been invented by the egyptians. They first divided it into 10 hours but then they divided it in 12 because of the twilight. So night time was divide in 12 hours because they wanted to see the stars in the night and also that there would be light in the day.
  • ...3 more annotations...
  • The subdivision of hours and minutes into 60 comes from the ancient Babylonians who had a predilection for using numbers to the base 60. For example, III II (using slightly different strokes) meant three times 60 plus two or 182.
  • "We have retained from the Babylonians not only hours and minutes divided into 60, but also their division of a circle into 360 parts or degrees," says Lomb.
  • While each country has (in broad terms) historically had distinct measurements for distance, weights etc the method of splitting the day into 24 hours, one hour into 60 mins and one minute into 60 seconds seems to be the only one in use, and indeed to me the only one I know of. This non-metric measurement of time is far from ideal, but what other comparably accurate methods have been used historically?
marino5856

Clocks - How Time Works - 1 views

science.howstuffworks.com/...time2.htm

How does the clock works

shared by marino5856 on 31 Oct 14 - No Cached
  • A day consists of two 12-hour periods, for a total of 24 hours. An hour consists of 60 minutes. A minute consists of 60 seconds. Seconds are subdivided on a decimal system into things like "hundredths of a second" or "millionths of a second."
    • marino5856
      marino5856 on 04 Nov 14
       
      There is 24 hours in a day because  they first divided 60 and that equals 12. So 12 plus 12 equals 24 so thats how they had 24 hours in a day.
  • hat's a pretty bizarre way to divide a day up. We divide it in half, then divide the halves by twelfths, then divide the twelfths into sixtieths, then divide by 60 again, and then convert to a decimal system for the smallest increments. It's no wonder children have trouble learning how to tell time.
  • How long is a day? It's the amount of time it takes for the Earth to rotate one time on its axis. But how long does it take the Earth to rotate? That is where things become completely arbitrary. The world has decided to standardize on the following increments:
  • ...3 more annotations...
  • Why are there 24 hours in a day? No one really knows. However, the tradition goes back a long way. Take, for example, this quote from Encyclopedia Britannica:
  • Why are there 60 minutes in an hour and 60 seconds in a minute? Again, it is unclear. It is known, however, that Egyptians once used a calendar that had 12 30-day months, giving them 360 days. This is believed to be the reason why we now divide circles into 360 degrees. Dividing 360 by 6 gives you 60, and 60 is also a base number in the Babylonian math system.
    • marino5856
      marino5856 on 04 Nov 14
       
      The Egyptians had a calendar that has 12 months so that equals 360 day in total. Also science they new that there is 360 days in a year thats why a circle is 360 degrees. The Roman people invented that so that in the clock there is not 24 hours in a clock so there is 12 am and 12pm.
  • What do a.m. and p.m. mean? These abbreviations stand for ante meridiem, before midday, and post meridiem, after midday, and they are a Roman invention. According to Daniel Boorstin in his book The Discoverers, this simple division of the day into two parts was the Romans' first increment of time within a day:
marino5856

Why We Divide the Day Into Seconds, Minutes, and Hours - 0 views

www.todayifoundout.com/...into-seconds-minutes-and-hours

divide seconds minutes hours

shared by marino5856 on 07 Nov 14 - No Cached
  • The concept of needing to divide up the day seems second nature to even the smallest kid who asks, “is it snack time”.   The reality is, even though we’ve decided that there is a need to divide up time, the actual process and the way we go about it has been changing for millennia.  The cruel irony is that even though we know we need to measure time, there has never been a consensus on what time really is.
    • marino5856
      marino5856 on 07 Nov 14
       
      The day is divided into minutes, seconds, and hours because of snack time so it all depended in how many times would we eat. That is equal to 12 hours plus the night so another 12 hours. Thats why there are 24 hours in a day.
Diego Hinojosa

Neptune -- Britannica School - 0 views

school.eb.com/...345012

neptune Atmosphere

shared by Diego Hinojosa on 04 Nov 14 - No Cached
  • The planet that Voyager uncovered is a stormy, windswept world with a vivid blue hue. Its highly active atmosphere is surprising, since it receives so little sunlight to power its weather systems. Like the other giant outer planets, Neptune has no solid surface. It also has a system of rings and more than a dozen moons.
    • Diego Hinojosa
      Diego Hinojosa on 04 Nov 14
       
      Neptune is a planet that has a lot of blue. It's atmosphere and also surface is not solid. It also has rings and like 12 moons.
  • Neptune is the smallest of the four giant outer planets. The diameter at its equator is about 30,775 miles (49,528 kilometers), as measured at a level of the atmosphere where the pressure is 1 bar (the pressure at sea level on Earth). This makes it slightly smaller than Uranus but nearly four times as big as Earth. Neptune’s mass is about 1.2 times greater than Uranus’, however, and more than 17 times greater than Earth’s. It is the third most massive planet in the solar system, after Jupiter and Saturn. Like the other outer planets, Neptune has a low density—only about 1.6 times the density of water. However, it is the densest of the four, being roughly 25 percent denser than Uranus.
    • Diego Hinojosa
      Diego Hinojosa on 04 Nov 14
       
      Neptune is also the smallest planet of the biggest four. The atmosphere of neptune is really thick.Neptune is the most hard planet in other words solid planet and it is four times bigger than the earth.
lobo5879

Five Stages Of Sleep ... Sleep Cycles Explained - 2 views

www.better-sleep-better-life.com/five-stages-of-sleep.html

stages sleep

shared by lobo5879 on 03 Nov 14 - No Cached
  • Stage 1This is the lightest stage of sleep, the transition phase, where you feel yourself drifting off. If you were to forget about the alarm clock and allow yourself to wake up naturally, Stage 1 sleep would be the last stage before you fully wake up. You don't spend too much time in Stage 1 sleep, typically five to 10 minutes, just enough to allow your body to slow down and your muscles to relax.
    • lobo5879
      lobo5879 on 04 Nov 14
       
      The stage 1 of sleep is when you are starting to relax your muscles and start to sleep. This stages is not very long it is about 5 to ten minutes. This stage is when you wake up more quickly for example if someone touches you you will easily wake up.
  • Stage 2The second stage of sleep is still considered light sleep. Your brain activity starts to slow down, as well as your heart rate and breathing. Your body temperature falls a little and you're beginning to reach a state of total relaxation in preparation for the deeper sleep to come.
  • Stage 3Stage 3 sleep is the start of deep sleep, also known as slow wave sleep. During stage 3, your brain waves are slow "delta waves," although there may still be short bursts of faster of brain activity (also known as beta-waves). If you were to get awakened suddenly during this stage, you would be groggy and confused, and find it difficult to focus at first.
    • lobo5879
      lobo5879 on 04 Nov 14
       
      this stage is when your body is finishing to relax and example is: if someone trys to wake you up you would be confused and do not know what is happening because you were already finishing to completely relax
  • ...3 more annotations...
  • Stage 4Of the five stages of sleep, this is the one when you experience your deepest sleep of the night. Your brain only shows delta-wave (slow wave) activity, and it's difficult to wake someone up when they're in Stage 4 of sleep.
    • lobo5879
      lobo5879 on 04 Nov 14
       
      this stage i when you are more hardly to be awaken. In this stage is when you start to dream and this stage is when the kids start having nightmares
  • It's during Stage 4 sleep that children are most likely to suffer from bedwetting or sleep terrors. Stages 3 and 4 can last anywhere from 5 - 15 minutes each, but the first deep sleep of the night is more likely to be an hour or so. This is the time when the body does most of it's repair work and regeneration.
  • Stage 5 This is the stage of sleep when you dream. It is also referred to as "active sleep" or REM sleep, which stands for the rapid eye movements that characterize Stage 5. During REM sleep, your blood flow, breathing, and brain activity increases. An EEG would show that your brain is about as active as it is when you're awake.Another aspect of Stage 5 sleep is that the muscles in your arms and legs will go through periods of paralysis. Scientists speculate that this may be nature's way of protecting us from acting out our dreams.The first period of REM sleep of the night usually begins about 90 minutes after you start drifting off, and lasts for about 10 minutes. As the night passes, the periods of REM sleep become longer, with the final episode lasting an hour or so.Babies may spend as much as half of the time they're asleep in the REM phase. For a healthy adult, Stage 5 occurs for about 20 to 25% of the time you are sleeping, and decreases with age.Scientists and researchers are continually learning more about the mechanics and physiological effects of sleep, and what happens during the five stages of sleep.
    • lobo5879
      lobo5879 on 04 Nov 14
       
      This stage is when you are completly relaxed and many babies are many time during this tage and adults are abaut 25% of they sleep
    • lobo5879
      lobo5879 on 06 Nov 14
       
      This stage is more dificult to wake up because you are alrady in deep sleep.
marino5856

BrainPOP | Time Zones - 0 views

www.brainpop.com/...timezones

brainpop time zones

shared by marino5856 on 03 Nov 14 - No Cached
    • marino5856
      marino5856 on 07 Nov 14
       
      The earth is divided in 24 time zones. Time zones go north south pole  to north pole, they are meridians, They are 360 that are degrees. Thats why they are different times. They are the same minute but different hour to the west of it  and highest hour to the east. Smaller goes to west  and bigger to east. The earth rotates. Thats why the hour changes. Like the sun is up it has a different hour than when the moon is up. The earth soins 15 degrees per hour. The sun rises in L.A. at the same minute than N.Y. when it is getting dark.
marino5856

Earth's Rotation - 0 views

www.polaris.iastate.edu/...unit3_sub1.htm

earth rotation 24 hours

shared by marino5856 on 07 Nov 14 - No Cached
  • The earth rotates about an imaginary line that passes through the North and South Poles of the planet.  This line is called the axis of rotation.  Earth rotates about this axis once each day (approximately 24 hours).  Although you most likely already knew that fact, there is a slight complication most people are not aware of.
  • More specifically, our rotation period (the time elapsed for one rotation) with respect to the stars  is called a sidereal day.  A sidereal day is 24 sidereal hours, or 23 hours and 56 minutes on a normal clock.  Our clock time is based on the earth's rotation with respect to the sun from solar noon to solar noon.  This is a solar day, and it is divided into 24 hours.  Because Earth travels about 1 / 365 of the way around the sun during one day, there is a small difference between solar time and sidereal time.
    • marino5856
      marino5856 on 07 Nov 14
       
      The earth rotates with axis lines and  there is 24 lines thats why there are 24 hours in a day. The earth time is rotated into 24hours because the earth rotate 1/365 during one day.
jaime5789

BBC Nature - Dinosaurs 'shrank' regularly to become birds - 0 views

www.bbc.co.uk/28563682

shared by jaime5789 on 04 Nov 14 - No Cached
  • Huge meat-eating, land-living dinosaurs evolved into birds by constantly shrinking for over 50 million years, scientists have revealed.
    • jaime5789
      jaime5789 on 04 Nov 14
       
      Gigantic dinosaurs evolved into the small birds we know today! Scientists think that dinosaurs evolved into birds, now people also think that dinosaurs used to have feathers! Big meat eating dinosaurs such as the Spinosaurus and T-Rex may have evolved into the modern birds we know today! 
    • jaime5789
      jaime5789 on 04 Nov 14
       
      Gigantic dinosaurs evolved into the small birds that we see today! Scientists think that dinosaurs evolved into birds, now people also think that dinosaurs used to have feathers! Big meat eating dinosaurs such as the Spinosaurus and T-Rex may have evolved into the modern birds we know today! 
    • jaime5789
      jaime5789 on 04 Nov 14
       
      Gigantic dinosaurs such as the Spinosaurus and T-Rex evolved into the small birds that we see today. Scientists think that dinosaurs evolved into birds, now people also think that dinosaurs used to have feathers! 
    • jaime5789
      jaime5789 on 05 Nov 14
       
      New Paraphrase: Did you know that dinosaurs, such as the Tyrannosaurus Rex and the fearsome Velociraptor became smaller, and after 50 million years, we now think that... 
  • Previous work has shown that theropod dinosaurs, the dinosaur group which included Tyrannosaurus rex and Velociraptor and gave rise to modern birds, must have decreased in size at some point in their evolution into small, agile flyers.
    • jaime5789
      jaime5789 on 04 Nov 14
       
      Now, work has shown that two legged dinosaurs including T-Rex and the fearsome Velociraptor gave birth to the birds we see today!
    • jaime5789
      jaime5789 on 05 Nov 14
       
      The University of Adelaide, wonders a lot about dinosaurs... They found out that dinosaurs such as Spinosaurus and Utahraptor made the birds we know today! 
  • But size changes frequently occurred in dinosaur evolution, so the research team members, led by Mike Lee, from the University of Adelaide, Australia, wanted to find out if the dramatic size reduction associated with the origin of birds was unique. They also wanted to measure the rate of evolution in dinosaurs using a large data set
    • jaime5789
      jaime5789 on 04 Nov 14
       
      Research indicates that dinosaurs constantly changed, the University of Adelaide wants to find out what makes the gigantic size changes? They found out that the evolution by dinosaur is unique and amazing! 
    • jaime5789
      jaime5789 on 04 Nov 14
       
      The University of Adelaide also wants to measure the the frequency of dinosaur evolution!
    • jaime5789
      jaime5789 on 05 Nov 14
       
      The U.O.A (University Of Adelaide) wonders, "how can something so big turn into something so small?" this is due to new eras, and the evolution of dinosaurs & birds!
  • ...9 more annotations...
  • They found that the dinosaur group directly related to birds shrank rapidly from about 200 million years ago.
    • jaime5789
      jaime5789 on 04 Nov 14
       
      Scientists found out that a dinosaur species related to birds shrank in a short time and probably turned into the birds we know today! 
    • jaime5789
      jaime5789 on 05 Nov 14
       
      Dinosaur species related to birds, shrank in a short period of time! We know believe that they turned into the birds that we're familiar with today! 
  • Theropods shrunk 12 times from 163kg (25st 9lb) to 0.8kg (1.8lb), before becoming modern birds.
    • jaime5789
      jaime5789 on 05 Nov 14
       
      Really big dinosaurs started shrinking and their weight decreased slowly..
  • The researchers found theropods were the only dinosaurs to get continuously smaller.
    • jaime5789
      jaime5789 on 05 Nov 14
       
      Scientists now know that the two-legged dinosaur species were the dinosaurs that frequently got smaller! 
  • From this analysis they produced a detailed family tree mapping out the transformation of theropods to their bird descendants.
    • jaime5789
      jaime5789 on 05 Nov 14
       
      We now predit that the two-legged dinosaurs transformed into birds!
  • It traces evolving adaptations and changing body size over time and across dinosaur branches.
    • jaime5789
      jaime5789 on 05 Nov 14
       
      We now think that dinosaurs adapted into transforming into birds little by little! 
  • The researchers concluded that the evolution of the branch of dinosaurs leading to birds was more innovative than other dinosaur lineages.
    • jaime5789
      jaime5789 on 05 Nov 14
       
      We conclude that, dinosaurs probably changed into birds! 
  • this sustained shrinking and accelerated evolution of smaller and smaller body size allowed the ancestors of birds to develop traits which helped them to cope much better than their less evolved dinosaur relatives.
    • jaime5789
      jaime5789 on 07 Nov 14
       
      Dinosaurs were getting smaller they developed traits to survive. 
  • The researchers believe that miniaturisation and the development of bird-like traits had a joint influence on the evolution of the dinosaurs into today's birds. Professor Michael Benton, from the University of Bristol's school of earth sciences, said: "This study means we can't see the origin of birds as a sudden or dramatic event, with a dinosaur becoming a powered flyer overnight. "The functions of each special feature of birds changed over time - feathers first for insulation, and later co-opted for flight; early reductions in body size perhaps for other reasons, and later they were small enough for powered flight; improvements in sense of sight and enlargement of brain - even a small improvement in these is advantageous. "So perhaps it's a long-term trend associated with deputation to a new set of habitats, in the trees, to avoid predation, and to exploit new food resources."
    • jaime5789
      jaime5789 on 07 Nov 14
       
      Researchers now think that the shrinking of the dinosaurs was what developed dinosaurs into todays birds! Professor Michael from the University of Bristol says that we can't study the era of birds, just like that...
    • jaime5789
      jaime5789 on 07 Nov 14
       
      This is a long process that didn't just happen like that, you sleep, you wake up and you're a bird, no! Its a very difficult process! 
  • "Birds evolved through a unique phase of sustained miniaturisation in dinosaurs," Mr Lee said.
    • jaime5789
      jaime5789 on 07 Nov 14
       
      Birds evolved due to the dinosaurs becoming smaller!
Diego Hinojosa

Uranus -- Britannica School - 0 views

school.eb.com/...339203

Atmosphere of Uranus

shared by Diego Hinojosa on 04 Nov 14 - No Cached
  • Uranus is the third largest planet in the solar system, after Jupiter and Saturn. Uranus is about four times bigger than Earth. Its diameter at the equator is about 31,763 miles (51,118 kilometers), as measured at the level of the atmosphere where the pressure is the same as at sea level on Earth. The planet is slightly larger than Neptune, but Neptune is about 1.2 times more massive. Uranus’ density is quite low—only about 1.3 times that of water, compared with 1.6 for Neptune and 5.5 for rocky Earth.
    • Diego Hinojosa
      Diego Hinojosa on 04 Nov 14
       
      Uranus is the third biggest planet on the whole solar system it is four times bigger than earth and it has a ver massive atmosphere
    • Diego Hinojosa
      Diego Hinojosa on 06 Nov 14
       
      Uranus is one of the 3 other planets that is the biggest on the whole solar system.It has a very harsh atmosphere.And it has very little water.
deleon6878

Should children have homework? | Debate.org - 0 views

www.debate.org/...should-children-have-homework

shared by deleon6878 on 04 Dec 14 - No Cached
  • I looked through the NO side. While I was doing so, I saw many errors. Most of the NO side complain that they have sports to do first, did it not occur to you that studies come first? If you fail school, the coach will (most likely) not let you play in that tournament/ game/ meet. As for the grammar errors on the NO side, I believe that many could use some Language Arts homework.
    • deleon6878
      deleon6878 on 04 Dec 14
       
      People don'y do homework cause their lazy and say they have a lot of homework has it ever come to mind that studies com first than sports.
  • Students should have homework because it prepares them for high school and college. If we don't prepare them in middle school and elementary school they will be more overloaded in high school and college because they didn't expect it. Long Live Homework! Plus, if we don't have homework, kids will go home and forget everything they learned.
    • deleon6878
      deleon6878 on 04 Dec 14
       
      If people do homework you prepare them for high school and collage plus they always have to review what they did that day 
  • 1. It helps you learn it better.2. It helps you understand it better.3. It tests you if you were listening while the lesson is being taught.4. It gives you problems to solve to help you get better at it.5. Homework is a good way to involve a child's family in the learning
    • deleon6878
      deleon6878 on 04 Dec 14
       
      "1. It helps you learn it better. 2. It helps you understand it better. 3. It tests you if you were listening while the lesson is being taught. 4. It gives you problems to solve to help you get better at it. 5. Homework is a good way to involve a child's family in the learning"
  • ...1 more annotation...
  • .Also if you manage your time correctly you would still have a good 4-5 hours of free time before you sleep.Homework prevents last minute studying and can often give you better marks in school
    • deleon6878
      deleon6878 on 05 Dec 14
       
      And if you use your time correctly you still have 4 or 5 hours of free time before bed plus you get better marks i8n school if you do homework 
marino5856

Why Do We Change the Clocks Twice a Year? | Wonderopolis - 0 views

wonderopolis.org/...change-the-clocks-twice-a-year

change of hours

shared by marino5856 on 14 Nov 14 - No Cached
  • it’s Daylight Saving Time! Daylight Saving Time (or “Summer Time,” as it’s known in many parts of the world) was created to make better use of the long sunlight hours of the summer. By “springing” clocks forward an hour in March, we move an hour of daylight from the morning to the evening. On the first Sunday in November, we “fall back” and rewind our clocks to return to Standard Time.
    • marino5856
      marino5856 on 14 Nov 14
       
      the hour changes to save daylight and light because like we have the sun light we don't need to waste la light. It changes in summer to have more light when it is getting night and in october again so that it is more dark because in winter we don't need so much the light.
Diego Hinojosa

The Astrolabe - 0 views

www.astrolabes.org

The astrolabe

shared by Diego Hinojosa on 18 Dec 14 - Cached
    • Diego Hinojosa
      Diego Hinojosa on 18 Dec 14
       
      The astrolabe is used to see how the sky looks at a specific time.
    • Diego Hinojosa
      Diego Hinojosa on 09 Feb 15
       
      The astrolabe was used for the time or era of the explorers. It has to do with stars and time. It can make use of were you are and the exact time as a watch but in the explorer era
marino5856

hour (unit of time) -- Encyclopedia Britannica - 0 views

global.britannica.com/...hour

hours 24 not 60

shared by marino5856 on 31 Oct 14 - No Cached
  • in timekeeping
  • 3,600 seconds, now defined in terms of radiation emitted from atoms of the element cesium under specified conditions. The hour was formerly defined as the 24th part of a mean solar day—i.e., of the average period of rotation of the Earth relative to the Sun. The hour of sidereal time, 1/24 of the Earth’s rotation period relative to the stars, was about 10 seconds shorter than the hour of mean solar time.
    • marino5856
      marino5856 on 05 Nov 14
       
      It also has 24 hours the earth because in the system of the egyptians it said that it also has 24 hours because of the earth spinning.
  • In even earlier systems of timekeeping, an hour was 1/12 of a period of daylight or darkness—hence, variable in length with seasonal changes in the length of day and night. The custom of dividing the cycle of day and night into 24 periods seems to have originated with the ancient Egyptians.
marino5856

World Clock: Time in the 24 World Time Zones - 0 views

www.elbertwade.com/page142.html

world time zones

shared by marino5856 on 10 Nov 14 - No Cached
    • marino5856
      marino5856 on 10 Nov 14
       
      There are actually 23hr and 59 minutes so they say it is 24 hours. The p.m starts again in one but this is how we count them: 13=1 pm, 14=2 pm 15= 3pm 16= 4 pm 17= 5 pm 18= 6 pm 19= 7 pm 20 =8 pm 21 = 9 pm 22= 10 pm 23 =11 pm. Pm is 23:59:59. AFter this its starts all over again.
  • At Noon, the 12-Hour clock repeats the same hour numbers but as PMAt Noon, the 24-Hour clock keeps adding hour numbers: 13 = 1 PM; 14 = 2 PM; 15 = 3 PM; 16 = 4 PM; 17 = 5 PM; 18 = 6 PM; 19 = 7 PM; 20 = 8 PM; 21 = 9 PM; 22 = 10 PM; 23 = 11 PM through 23:59:59 -- then starts over at 00:00:00 (Midnight)On both clocks, the minutes and seconds are exactly the same
guzman5860

Why is the sky blue? :: NASA's The Space Place - 0 views

spaceplace.nasa.gov/en

works Facts sky blue nasa

shared by guzman5860 on 31 Oct 14 - No Cached
  • Sunlight reaches Earth's atmosphere and is scattered in all directions by all the gases and particles in the air. Blue light is scattered in all directions by the tiny molecules of air in Earth's atmosphere. Blue is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time
    • guzman5860
      guzman5860 on 04 Nov 14
       
      The blue light is sometimes scattered more than the other colors because all the molecules or particles that are in the atmosphere go in all directions and the wavelength is shorter and it has smaller waves so thats why the sky is blue most of the time.
    • guzman5860
      guzman5860 on 06 Nov 14
       
      The blue light is scattered the more than the other colors Because all the particles and molecules  that are in the atmosphere go in all directions and it spreads and the blue wavelength is shorter and the waves are smaller and it has lots of energy thats why the sky is blue
guzman5860

Why Is The Sky Blue? - Geography For Kids - By KidsGeo.com - 1 views

www.kidsgeo.com/...0045-why-is-the-sky-blue.php

blue sky kids

shared by guzman5860 on 31 Oct 14 - No Cached
  • As the light from our Sun shines into the atmosphere, most of the colors are able to reach the Earth’s surface uninterrupted. However, because blue light has a wavelength that is the same size as the particulates in the air, this light is scattered in every direction. This blue light bounces from particulate to particulate until it eventually reaches your eyes. For this reason, no matter what direction you look in the sky, it appears to be blue. This blue light originated with the Sun, was bounced around in the sky many times, and then eventually reached your eyes.
    • guzman5860
      guzman5860 on 04 Nov 14
       
      The blu light bounces from particulate to particulate until it reaches your eye and it wont  matter on what part of the sky you look at it is going to appear blue. 
    • guzman5860
      guzman5860 on 06 Nov 14
       
      The blue light of the sky bounces from one particulate to another many times and if you see up to the sky it is going to appear blue.
marino5856

Why is a minute divided into 60 seconds, an hour into 60 minutes, yet there are only 24... - 0 views

www.scientificamerican.com/...me-division-days-hours-minutes

60 minute seconds minutes

shared by marino5856 on 05 Nov 14 - No Cached
  • Thanks to documented evidence of the Egyptians' use of sundials, most historians credit them with being the first civilization to divide the day into smaller parts. The first sundials were simply stakes placed in the ground that indicated time by the length and direction of the resulting shadow. As early as 1500 B.C., the Egyptians had developed a more advanced sundial.
    • marino5856
      marino5856 on 06 Nov 14
       
      Thanks to the duodecimal system. The  egyptians used the system to make counting more easier. Also the number 12 is typically attributed.
  • A T-shaped bar placed in the ground, this instrument was calibrated to divide the interval between sunrise and sunset into 12 parts. This division reflected Egypt's use of the duodecimal system--the importance of the number 12 is typically attributed either to the fact that it equals the number of lunar cycles in a year or the number of finger joints on each hand (three in each of the four fingers, excluding the thumb), making it possible to count to 12 with the thumb.
  • The next-generation sundial likely formed the first representation of what we now call the hour. Although the hours within a given day were approximately equal, their lengths varied during the year, with summer hours being much longer than winter hours
  • ...1 more annotation...
  • Egyptian astronomers also first observed a set of 36 stars that divided the circle of the heavens into equal parts. The passage of night could be marked by the appearance of 18 of these stars, three of which were assigned to each of the two twilight periods when the stars were difficult to view. The period of total darkness was marked by the remaining 12 stars, again resulting in 12 divisions of night (another nod to the duodecimal system).
    • marino5856
      marino5856 on 06 Nov 14
       
      Egyptians noticed that there was 36 stars in each part so they divided that into equal parts 12.
Nany Rocha

Henry Hudson - Facts & Summary - HISTORY.com - 0 views

www.history.com/...henry-hudson

henry hudson history

shared by Nany Rocha on 24 Nov 14 - No Cached
  • wice being turned back by ice, Hudson embarked on a third voyage–this time on behalf of the Dutch East India Company–in 1609. This time, he chose to continue east by a more southern route, drawn by reports of a possible channel across the North American continent to the Pacific. After navigating the Atlantic coast, Hudson’s ships sailed up a great river (which would later bear his name) but turned back when they determined it was not the channel they sought. On a fourth and final voyage, undertaken for England in 1610-11, Hudson spent months drifting through the vast Hudson Bay and eventually fell victim to a mutiny by his crew. Hudson’s discoveries laid the groundwork for Dutch colonization of the Hudson River region, as well as English land claims in Canada.
  • enry Hudson made his first voyage west from England in 1607, when he was hired to find a shorter route to Asia from Europe through the Arctic Ocean. After
  • tic Ocean. After
  • ...3 more annotations...
  • s hired to find a shorter route to Asia from
  • n Bay and eventually fell victim to a mutiny by his crew. Hudson’s discoveries laid the groundwork for Dutch colonization of the Hudson River region, as well as Englis
  • ken for England in 1610-11, Hudson spent months drifting through the vast Hudson Bay and eventually fell victim to a mutiny by his crew. Hudson’s discoveries laid the groundwork for Dutch colonization of the Hudson River region, as w
Esteban Cantu

Moons of Jupiter - Wikipedia, the free encyclopedia - 0 views

en.wikipedia.org/...Moons_of_Jupiter

jupiter

shared by Esteban Cantu on 11 Nov 14 - Cached
  • For two decades no additional moons were discovered; but between October 1999 and February 2003, researchers using sensitive ground-based detectors found and later named another 34 moons,
    • Esteban Cantu
      Esteban Cantu on 11 Nov 14
       
      On 1999 to 2003 34 more moons of jupiter were discovered.
  • The moons' physical and orbital characteristics vary widely. The four Galileans are all over 3,100 kilometres (1,900 mi) in diameter; the largest Galilean, Ganymede, is the ninth largest object in the Solar System, after the Sun and seven of the planets (Ganymede being larger than Mercury). All other Jovian moons are less than 250 kilometres (160 mi) in diameter, with most barely exceeding 5 kilometres (3.1 mi). Orbital shapes range from nearly perfectly circular to highly eccentric and inclined, and many revolve in the direction opposite to Jupiter's spin (retrograde motion). Orbital periods range from seven hours (taking less time than Jupiter does to spin around its axis), to some three thousand times more (almost three Earth years).
    • Esteban Cantu
      Esteban Cantu on 14 Nov 14
       
      Ganymede, one of Jupiter's four galilean moons, is bigger than Mercury. 
  • ...1 more annotation...
  • Main group or Galilean moons: Io, Europa, Ganymede and Callisto. They are some of the largest objects in the Solar System outside the Sun and the eight planets in terms of mass and larger than any known dwarf planet, and Ganymede exceeds the planet Mercury in diameter.
    • Esteban Cantu
      Esteban Cantu on 14 Nov 14
       
      4 of Jupiter's moons, the galilean moons, are some of the largest objects in our universe.
garza6544

Do Cats Have a Sense of Taste? - 0 views

www.cathealth.com/...do-cats-have-a-sense-of-taste

cats sense of taste

shared by garza6544 on 11 Nov 14 - No Cached
  • The sense of smell is extremely important in attracting cats (and us) to food and also in aiding tasting food. Cat’s noses are many times more sensitive than our own, so it is believed that their heightened sense of smell assists a great deal in their tasting of different flavors.
    • garza6544
      garza6544 on 11 Nov 14
       
      the sence of smell is very important for cats and us and also tastig food. heir nose is like 100 times more sensitive than ours, that helps for taste too.
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