How do we measure the universe?

The universe is very large may be obvious, but sometimes it is worth remembering: the universe is very big ... if you think about it and ponder for a moment, the truth is not so obvious. Moreover, even really difficult to imagine how big it is.

Our usual measures are wasted when we put them face to face with the immensity that surrounds us. And one of the issues that most often appear when trying to measure the Universe is the same: How? How do astronomers know a star or galaxy is 8,000 million light years away?

M65 and M66

In close proximity bright spiral galaxies M65 and M66 are highlighted in this attractive cosmic image. The pair is about 35 million light years and measured, each, about 100,000 light-years .

Both display prominent dust lanes that spiral arms sweep. M66 has a particularly striking contrast of red and blue colors, the red light shows the regions of hydrogen gas to form stars and star clusters.

M65 and M66 are two of the three galaxies known as the Leo Triplet , where the gravitational effect of the tide including how matter warps, evidence of how close they are.

M66 has been home to four brilliant supernovae since 1973 .

Dragon private space freighter successfully entered orbit term

The U.S. ship company SpaceX Dragon, the first space freighter urban by a private company launched from Cape Canaveral, Florida, successfully separated the Falcon 9 booster rocket, entered into an intermediate orbit prior to approaching Space Station (ISS) and solar panels deployed, NASA reported on its website that broadcast the event online.

The launch, postponed several times, finally came at 7.44 GMT on Tuesday. The separation of the propellant occurred after about 10 minutes, and the solar panels are opened shortly thereafter. Two hours after take-off will be launched on-board sensors that allow the freighter to the ISS approach and make the connection but the approach will be initiated only on the third day.

It is an experimental flight, so the ISS Dragon takes just a load of just 520 kilos: some equipment for experiments, notebooks, batteries, clothes and 117 standard food rations for astronauts. In the future, can carry up to six tons to low orbit and bring back some three tons.

Originally, SpaceX planned to launch the spacecraft on Saturday, May 19, but returned to cancel, by excess pressure in one of nine propellant rocket motors, when the countdown to the launch was over.

In 2006, NASA launched a program that encourages private projects of ships capable of transporting cargo to the orbit and the ISS. SpaceX took four years to develop its Dragon spacecraft in December 2010 made the first flight into orbit and splashed down in the Pacific. To date, the company invested in the project about 1,200 million dollars. Almost a third of this amount was funded by NASA.