Getting to Know the Universe
7 Surprising facts about the Universe.........
1. The Universe Is Old (Really Old)
The universe began with the Big Bang, and is estimated to be approximately 13.7 billion years old (plus or minus 130 million years). Astronomers calculated this figure by measuring the composition of matter and energy density in the universe, which enabled them to determine how fast the universe expanded in the past. As a result, researchers could turn back the hands of time and pinpoint when the Big Bang occurred. The time in between that explosion and now makes up the age of the universe.2. The Universe Is Getting Bigger
In
the 1920s, astronomer Edwin Hubble made the revolutionary discovery
that the universe is not static, but rather is expanding. But, it was
long thought that the gravity of matter in the universe would slow this
expansion or even cause it to contract.
In 1998, the Hubble Space Telescope studied very distant supernovas
and found that, a long time ago, the universe was expanding more slowly
than it is today. This puzzling discovery suggested that an inexplicable
force, called dark energy, is driving the accelerating expansion of the
universe.
While dark energy is thought to be the strange force that is pulling the cosmos apart at ever-increasing speeds, it remains one of the greatest mysteries in science because its detection remains elusive to scientists.
Mysterious dark energy is not
only thought to be driving the expansion of the universe, it appears to
be pulling the cosmos apart at ever-increasing speeds. In 1998, two
teams of astronomers announced that not only is the universe expanding,
but it is accelerating as well. According to the researchers, the
farther a galaxy is from Earth, the faster it is moving away.
The universe's acceleration also confirms Albert Einstein's theory of
general relativity, and lately, scientists have revived Einstein's
cosmological constant to explain the strange dark energy that seems to
be counteracting gravity and causing the universe to expand at an
accelerating pace.
While dark energy is thought to be the strange force that is pulling the cosmos apart at ever-increasing speeds, it remains one of the greatest mysteries in science because its detection remains elusive to scientists.
3. The Universe's Growth Spurt Is Accelerating
Three scientists won the 2011 Nobel Prize in Physics for their 1998 discovery that the expansion of the universe was accelerating.
4. The Universe Could Be Flat
The shape of the universe is influenced by the struggle between the pull of gravity (based on the density of the matter in the universe) and the rate of expansion. If the density of the universe exceeds a certain critical value, then the universe is "closed," like the surface of a sphere. This implies that the universe is not infinite but has no end. In this case, the universe will eventually stop expanding and start collapsing in on itself, in an event known as the "Big Crunch." If the density of the universe is less than the critical density value, then the shape of the universe is "open," like the surface of a saddle. In this case, the universe has no bounds and will continue to expand forever.Yet, if the density of the universe is exactly equal to the critical density, then the geometry of the universe is "flat," like a sheet of paper. Here, the universe has no bounds and will expand forever, but the rate of expansion will gradually approach zero after an infinite amount of time. Recent measurements suggest that the universe is flat with roughly a 2 percent margin of error.
5. The Universe Is Filled With Invisible Stuff
6. The Universe Has Echoes of Its Birth
The cosmic microwave background is made up of light echoes left over from the Big Bang that created the universe 13.7 billion years ago. This relic of the Big Bang explosion hangs around the universe as a pocked veil of radiation.
The European Space Agency's Planck mission mapped the entire sky in
microwave light to reveal new clues about how the universe began.
Planck's observations are the most precise views of the cosmic microwave
background ever obtained. Scientists are hoping to use data from the
mission to settle some of the most debated questions in cosmology, such
as what happened immediately after the universe was formed.
7. There May Be More Universes
Researchers searched the best available observations of the cosmic microwave background for signs of bubble universe collisions, but didn't find anything conclusive. If two universes had collided, the researchers say, it would have left a circular pattern behind in the cosmic microwave background.
Do u know how RFID works???
Long checkout lines at the grocery store are one of the biggest complaints about the shopping experience. Soon, these lines could disappear when the ubiquitous Universal Product Code (UPC) bar code is replaced by smart labels, also called radio frequency identification (RFID) tags. RFID tags are intelligent bar codes that can talk to a networked system to track every product that you put in your shopping cart.
Imagine going to the grocery store, filling up your cart and walking right out the door. No longer will you have to wait as someone rings up each item in your cart one at a time. Instead, these RFID tags will communicate with an electronic reader that will detect every item in the cart and ring each up almost instantly. The reader will be connected to a large network that will send information on your products to the retailer and product manufacturers. Your bank will then be notified and the amount of the bill will be deducted from your account. No lines, no waiting.
RFID tags, a technology once limited to tracking cattle, are tracking consumer products worldwide. Many manufacturers use the tags to track the location of each product they make from the time it's made until it's pulled off the shelf and tossed in a shopping cart.
Outside the realm of retail merchandise, RFID tags are tracking vehicles, airline passengers, Alzheimer's patients and pets. Soon, they may even track your preference for chunky or creamy peanut butter. Some critics say RFID technology is becoming too much a part of our lives -- that is, if we're even aware of all the parts of our lives that it affects.
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