Black Hole and Time Travel?

     Black holes are, without doubt, the most mysterious and unknown place in the universe. First of all, scientists theorize that anything can form into a black hole as long as it is compressed into an extremely dense space that exhibits gravitational pull so great that not even light could escape. For instance, squeezing the whole entire Earth into something as small as a peanut, or compressing Mount Everest into a micrometer.

  Time and space distortion caused by a black hole          

 
  The gravitational field has the ability to bend space and time, thus generating the theory that time travel is made possible by entering wormholes. Another theory stated by Stephen Hawking says that time distortion can be achieved by circling a spaceship around a black hole. Without crossing the event of horizon, an imaginary boundary that prevents an object from falling into the black hole, it is possible that a spaceship could circle around a black hole.  For instance, the space agency on Earth would notice that it takes 16 minutes to orbit around the black hole. However, for the people on board, time would be slowed down by half !! For a 16-minute-orbit, they would only experience 8 minutes of time. The ship and the crew on board would be traveling through time unconsciously.  Imagine if the ship and the crew continues to circle the black hole for 5 years, 10 years would pass on Earth. By the time they return, they would return to a future Earth. But, of course, this is all hypothesized. However, in my opinion, this is the most scientific approach of time travel and this can be achieved through accurate calculations of the event of horizon.

     (Stephen Hawking- Black Hole Time Travel)

Time Machine Within Us?

      A  recent conversation with my biology teacher inspired me to write this post. An interesting question surfaced and I would like to share it with you all !!! ♥

    It takes sunlight approximately 8 minutes to reach Earth. Different conclusions can be drawn from this piece of information. For instance, the sunlight you see now out the window is the sunlight emitted eight minutes ago. In other words, it would take the Earth eight minutes to realize that the Sun is missing after its actual disappearance. DUN-DUN-DUN (~insert drum rolls~) The Sun could actually be dead right now but we just don't know because we are still living in the radiation cast by the Sun. Thus, whenever you look up at the sun, you see it as the it was eight minutes ago! Pretty amazing right?

    A similar scenario would be seeing the light from another star when the star has already been dead. For examples, a light year is the distance light travels in a year. Therefore, a star that is located 10,000 light years away would emit light that's going to reach Earth in approximately one million years. When the light is detected, the actual star would mostly likely be dead by then. In other words, the distance between Earth and the star is so great that it takes light 10,000 years to travel to Earth, which by then, the star no longer exists. Keep this in mind, any star you see now, you see into its history instead of the way it is.  Now, would you compare your eyes to a time machine? The fact that we, human beings, see into the history of stars, never fails to fascinate and enthrall me of the various possibilities that the universe can offer ! I hope you enjoyed reading this post and stay tuned for the next one!

An interesting quote to reflect on.
(http://picgerm.com/the-star-quotes/)

Brightest Object in the Universe?

The Sun
(Google image)

   I first learned about Quasars when I was watching Youtube videos by Vsauce (Michael Stevens). This channel comprises of videos that discuss various topics ranging from mind-blowing science facts to interesting internet controversies.  Thus, I strongly recommend these videos for entertainment and educational purposes.

    The Sun is most likely the first celestial body that comes to your mind when the word "bright" is mentioned. Remember that stinging sensation when you squint your eyes at the blinding Sun. Now, imagine yourself staring at an object a trillion times brighter and bigger than the Sun---A Quasar. 

   Quasars are first discovered in the 1960s and are named quasi-stellar radio sources. Their source of energy are believed to be generated by massive black holes that are located at the center of the galaxy containing the Quasar. In fact, the Quasar itself is believed to be "a supermassive black hole surrounded by an accretion disk, a flat, disk-like structure of gas" (Quasars- Astronomy For Kids).  A Quasar may appear as a faint red star to us through the help of a telescope, this is due to its distance from Earth. Having such high luminosity, or brightness, a Quasar surpasses the brightness of other stars within the galaxy. 

(A Quasar is depicted by an artist as a luminous black
 hole surrounded by a disk-like structure of gas)

              What's The Brightest Thing In the 

            Universe?   Vsauce (Youtube)

 

Bibliography

1. http://www.universetoday.com/73222/what-is-a-quasar/

2.https://www.youtube.com/watch?v=FJB7gbjiJKw

3. http://www.kidsastronomy.com/quasar.htm

4.http://www.space.com/17262-quasar-definition.html

5.http://starchild.gsfc.nasa.gov/docs/StarChild/universe_level2/quasars.html