Space Calendar January 31 – February 6 2011

Space related activities and anniversaries for January 31 – February 6 2011. Fetched live every week from NASA JPL

If you want the complete list going more than a year ahead then see the Space Calendar at NASA JPL.

NASA’s Hubble Finds Most Distant Galaxy Candidate Ever Seen in Universe

NASA's Hubble Finds Most Distant Galaxy Candidate Ever Seen in Universe

Astronomers have pushed NASA’s Hubble Space Telescope to its limits by finding what they believe is the most distant object ever seen in the universe. Its light traveled 13.2 billion years to reach Hubble, roughly 150 million years longer than the previous record holder. The age of the universe is 13.7 billion years.

The dim object, called UDFj-39546284, is a compact galaxy of blue stars that existed 480 million years after the Big Bang, only four percent of the universe’s current age. It is tiny. Over one hundred such mini-galaxies would be needed to make up our Milky Way.

Astronomers were surprised to find evidence that the rate at which the universe was forming stars grew precipitously in about a 200-million-year time span.

“We’re seeing huge changes in the rate of star birth that tell us that if we go a little further back in time we’re going to see even more dramatic changes,” says Garth Illingworth of the University of California at Santa Cruz. The rate of star birth increased by about a factor of ten going from 480 million years to 650 million years after the Big Bang.

[SOURCE: hubblesite.org]

Looking Over Enceladus

Looking Over Enceladus

[SOURCE: saturn.jpl.nasa.gov]

Cassini Top 10 Science Highlights of 2010

Cassini Top 10 Science Highlights of 2010

[SOURCE: saturn.jpl.nasa.gov]

Top Images of 2010

Top Images of 2010

[SOURCE: saturn.jpl.nasa.gov]

Space Calendar January 24 – January 30 2011

Space related activities and anniversaries for January 24 – January 30 2011. Fetched live every week from NASA JPL

If you want the complete list going more than a year ahead then see the Space Calendar at NASA JPL.

Dione’s Deception

Dione's Deception

[SOURCE: saturn.jpl.nasa.gov]

The Best Way to Measure Dark Energy Just Got Better

The Best Way to Measure Dark Energy Just Got Better

Dark energy is a mysterious force that pervades all space, acting as a “push” to accelerate the Universe’s expansion. Despite being 70 percent of the Universe, dark energy was only discovered in 1998 by two teams observing Type Ia supernovae. A Type 1a supernova is a cataclysmic explosion of a white dwarf star.

These supernovae are currently the best way to measure dark energy because they are visible across intergalactic space. Also, they can function as “standard candles” in distant galaxies since the intrinsic brightness is known. Just as drivers estimate the distance to oncoming cars at night from the brightness of their headlights, measuring the apparent brightness of a supernova yields its distance (fainter is farther). Measuring distances tracks the effect of dark energy on the expansion of the Universe.

[SOURCE: www.cfa.harward.edu]

Space Calendar January 17 – January 23 2011

Space related activities and anniversaries for January 17 – January 23 2011. Fetched live every week from NASA JPL

If you want the complete list going more than a year ahead then see the Space Calendar at NASA JPL.

Cosmology Standard Candle Not So Standard After All

Cosmology Standard Candle Not So Standard After All

PASADENA, Calif. — Astronomers have turned up the first direct proof that “standard candles” used to illuminate the size of the universe, termed Cepheids, shrink in mass, making them not quite as standard as once thought. The findings, made with NASA’s Spitzer Space Telescope, will help astronomers make even more precise measurements of the size, age and expansion rate of our universe.

Standard candles are astronomical objects that make up the rungs of the so-called cosmic distance ladder, a tool for measuring the distances to farther and farther galaxies. The ladder’s first rung consists of pulsating stars called Cepheid variables, or Cepheids for short. Measurements of the distances to these stars from Earth are critical in making precise measurements of even more distant objects. Each rung on the ladder depends on the previous one, so without accurate Cepheid measurements, the whole cosmic distance ladder would come unhinged.

[SOURCE: spitzer.caltech.edu]