Archive for the ‘Astronomy’ Category

Live Web Cast of the 2012 Transit of Venus

Tuesday, June 5th, 2012

Source – NASA TV:

Live Video app for Facebook by Ustream

NASA Science – Solar Eclipse in the USA (May 20, 2012)

Monday, May 7th, 2012

Source – Science@NASA:

See Older post for google maps that show the path of the Eclipse.

A “ring of fire” solar eclipse is coming to the USA this spring. It’s the first annular eclipse visible from the contiguous United States in almost 18 years.

Super Moon of May 2012

Saturday, May 5th, 2012

Source – ScienceCasts: The Super Moon of May 2012:

Another “super-Moon” is in the offing. The perigee full Moon in May will be as much as 14% bigger and 30% brighter than other full moons of 2012.

NASA / JPL What’s Up For May 2012

Saturday, May 5th, 2012

Source – NASA /JPL Solar System Exploration:

View sunspots and a solar eclipse through solar-safe ‘scopes this month.

ScienceCasts: A Wonderful Night in April

Thursday, April 19th, 2012

Source – Science@NASA:

If you have to chose just one night in April to go out and look at the stars, NASA scientists say it should be April 21st. This week’s ScienceCast explains what makes that one night so special.

Annular Solar eclipse of May 20, 2012

Wednesday, April 11th, 2012

Source – Wikipedia, the free encyclopedia:

An annular solar eclipse will take place on May 20, 2012 (May 21, 2012 for local time in Eastern Hemisphere), with a magnitude of 0.9439. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partially obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon’s apparent diameter is smaller than the Sun, causing the Sun to look like an annulus (ring), blocking most of the Sun’s light. An annular eclipse appears as a partial eclipse over a region thousands of kilometres wide.

The annular phase will be visible from the Chinese coast, the south of Japan, and the western part of the United States and Canada. Guangzhou, Tokyo and Albuquerque will be on the central path. Kanarraville, Utah will be a perfect place to view the annular phase. Its maximum will occur in the North Pacific, south of the Aleutian islands for 5 min and 46.3 s, and finish in the western United States.

It will be the first central eclipse of the 21st century in the continental USA, and also the first annular eclipse there since the solar eclipse of May 10, 1994 which was also the previous eclipse of this series Solar Saros 128.

Google Map of Annular Solar Eclipse

NASA /JPL What’s up for April 2012

Wednesday, April 11th, 2012

Source – NASA /JPL Solar System Exploration:

View Saturn all night this month, and view icy moons through a telescope.

NASA Discovers First Earth-size Planets Beyond Our Solar System

Tuesday, December 20th, 2011

Source – NASA /JPL Kepler:

MOFFET FIELD, Calif. — NASA’s Kepler mission has discovered the first Earth-size planets orbiting a sun-like star outside our solar system. The planets, called Kepler-20e and Kepler-20f, are too close to their star to be in the so-called habitable zone where liquid water could exist on a planet’s surface, but they are the smallest exoplanets ever confirmed around a star like our sun.

The discovery marks the next important milestone in the ultimate search for planets like Earth. The new planets are thought to be rocky. Kepler-20e is slightly smaller than Venus, measuring 0.87 times the radius of Earth. Kepler-20f is a bit larger than Earth, measuring 1.03 times its radius. Both planets reside in a five-planet system called Kepler-20, approximately 1,000 light-years away in the constellation Lyra.

Kepler-20e orbits its parent star every 6.1 days and Kepler-20f every 19.6 days. These short orbital periods mean very hot, inhospitable worlds. Kepler-20f, at 800 degrees Fahrenheit, is similar to an average day on the planet Mercury. The surface temperature of Kepler-20e, at more than 1,400 degrees Fahrenheit, would melt glass.

“The primary goal of the Kepler mission is to find Earth-sized planets in the habitable zone,” said Francois Fressin of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., lead author of a new study published in the journal Nature. “This discovery demonstrates for the first time that Earth-size planets exist around other stars, and that we are able to detect them.”

The Kepler-20 system includes three other planets that are larger than Earth but smaller than Neptune. Kepler-20b, the closest planet, Kepler-20c, the third planet, and Kepler-20d, the fifth planet, orbit their star every 3.7, 10.9 and 77.6 days. All five planets have orbits lying roughly within Mercury’s orbit in our solar system. The host star belongs to the same G-type class as our sun, although it is slightly smaller and cooler.

The system has an unexpected arrangement. In our solar system, small, rocky worlds orbit close to the sun and large, gaseous worlds orbit farther out. In comparison, the planets of Kepler-20 are organized in alternating size: large, small, large, small and large.

“The Kepler data are showing us some planetary systems have arrangements of planets very different from that seen in our solar system,” said Jack Lissauer, planetary scientist and Kepler science team member at NASA’s Ames Research Center in Moffett Field, Calif. “The analysis of Kepler data continue to reveal new insights about the diversity of planets and planetary systems within our galaxy.”

Scientists are not certain how the system evolved but they do not think the planets formed in their existing locations. They theorize the planets formed farther from their star and then migrated inward, likely through interactions with the disk of material from which they originated. This allowed the worlds to maintain their regular spacing despite alternating sizes.

The Kepler space telescope detects planets and planet candidates by measuring dips in the brightness of more than 150,000 stars to search for planets crossing in front, or transiting, their stars. The Kepler science team requires at least three transits to verify a signal as a planet.

The Kepler science team uses ground-based telescopes and the Spitzer Space Telescope to review observations on planet candidates the spacecraft finds. The star field Kepler observes in the constellations Cygnus and Lyra can be seen only from ground-based observatories in spring through early fall. The data from these other observations help determine which candidates can be validated as planets.

To validate Kepler-20e and Kepler-20f, astronomers used a computer program called Blender, which runs simulations to help rule out other astrophysical phenomena masquerading as a planet.

On Dec. 5 the team announced the discovery of Kepler-22b in the habitable zone of its parent star. It is likely to be too large to have a rocky surface. While Kepler-20e and Kepler-20f are Earth-size, they are too close to their parent star to have liquid water on the surface.

“In the cosmic game of hide and seek, finding planets with just the right size and just the right temperature seems only a matter of time,” said Natalie Batalha, Kepler deputy science team lead and professor of astronomy and physics at San Jose State University. “We are on the edge of our seats knowing that Kepler’s most anticipated discoveries are still to come.”

NASA’s Ames Research Center in Moffett Field, Calif., manages Kepler’s ground system development, mission operations and science data analysis. JPL managed the Kepler mission’s development.

Ball Aerospace and Technologies Corp. in Boulder, Colo., developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

The Space Telescope Science Institute in Baltimore archives, hosts and distributes Kepler science data. Kepler is NASA’s 10th Discovery Mission and is funded by NASA’s Science Mission Directorate at the agency’s headquarters in Washington.

For more information about the Kepler mission and to view the digital press kit, visit:

What’s Up for December 2011?

Sunday, December 11th, 2011

Source – NASA /JPL Solar System Exploration:

A mission recap and lots of planets to view.

Discovery of Earth-size planets in or near the “habitable zone,”

Thursday, December 1st, 2011

Source – National Optical Astronomy Observatory:

NOAO: New Planet Kepler-21b discovery a partnership of both space and ground-based observations

The NASA Kepler Mission is designed to survey a portion of our region of the Milky Way Galaxy to discover Earth-size planets in or near the “habitable zone,” the region in a planetary system where liquid water can exist, and determine how many of the billions of stars in our galaxy have such planets. It now has another planet to add to its growing list. A research team led by Steve Howell, NASA Ames Research Center, has shown that one of the brightest stars in the Kepler star field has a planet with a radius only 1.6 that of the earth’s radius and a mass no greater that 10 earth masses, circling its parent star with a 2.8 day period. With such a short period, and such a bright star, the team of over 65 astronomers (that included David Silva, Ken Mighell and Mark Everett of NOAO) needed multiple telescopes on the ground to support and confirm their Kepler observations. These included the 4 meter Mayall telescope and the WIYN telescope at Kitt Peak National Observatory. The accompanying figure shows the size of the Kepler field, seen over Kitt Peak.

With a period of only 2.8 days, this planet, designated Kepler-21b, is only about 6 million km away from its parent star. By comparison Mercury, the closest planet to the sun, has a period of 88 days and a distance from the sun almost ten times greater, or 57 million km. So Kepler 21b is far hotter than any place humans could venture. The team calculates that the temperature at the surface of the planet is about 1900 K, or 2960 F. While this temperature is nowhere near the habitable zone in which liquid water might be found, the planet’s size is approaching that of the earth.

The parent star, HD 179070, is quite similar to our sun: its mass is 1.3 solar masses, its radius is 1.9 solar radii, and its age, based on stellar models, is 2.84 billion years (or a bit younger than the sun’s 4.6 billion years). HD 179070 is spectral type F6 IV, a little hotter and brighter than the sun. By astronomical standards, HD 179070 is fairly close, at a distance from the sun of 352 light years. While it cannot be seen by the unaided eye, a small telescope can easily pick it out.

Part of the difficulty in detecting this planet is the realization, from the Kepler mission, that many stars show short period brightness oscillations. The effect of these must be removed from the stellar light in order to uncover the regular, but very small, dimming caused by the planet passing in front of the star. The Kepler mission observed this field for over 15 months, and the team combined the observations to enable them to detect this tiny, periodic signal. They also relied on spectroscopic and imaging data from a number of ground based telescopes. The attached figure 2 shows a light curve: a plot of the brightness of HD 179070 over time as the planet passes in front of it. This curve was built up over the many months of observing.

The results of this work have been accepted for publication in the Astrophysical Journal.

NOAO is operated by Association of Universities for Research in Astronomy Inc. (AURA) under a cooperative agreement with the National Science Foundation.