Posts Tagged ‘astro physics’

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360 Degree Panorama – Milky Way Arches Over Chile

12/10/2011

The Milky Way arches across this rare 360-degree panorama of the night sky above the Paranal observing platform in Chile, home of ESO’s Very Large Telescope.

The image was made from 37 individual frames with a total exposure time of about 30 minutes, taken in the early morning hours. The Moon is just rising and the zodiacal light shines above it, while the Milky Way stretches across the sky opposite the observatory.

Click For Enlarged Image - Its Gorgeous!

The open telescope domes of the world’s most advanced ground-based astronomical observatory are all visible in the image: the four smaller 1.8-metre Auxiliary Telescopes that can be used together in the interferometric mode, and the four giant 8.2-metre Unit Telescopes.

To the right in the image and below the arc of the Milky Way, two of ESO’s galactic neighbours, the Small and Large Magellanic Clouds, can be seen.

An interactive virtual tour is available here

Image Credit: ESO/H.H. Heyer

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NASA Selects Science Proposals For Concept Studies – Sun, Milky Way, Earth’s Atmosphere

29/09/2011

PASADENA, Calif. — NASA has selected 11 science proposals, including one from the Jet Propulsion Laboratory, for evaluation as potential future science missions. The proposals outline prospective missions to study the Earth’s atmosphere, the sun, the Milky Way galaxy, and Earth-like planets around nearby stars.

The selections were made from responses to Announcements of Opportunity for Explorer Missions and Explorer Missions of Opportunity released by the agency last November. The proposals were judged to have the best science value and feasible development plans.

“NASA continues to seek opportunities to push the cutting edge of science,” said Paul Hertz, chief scientist for NASA’s Science Mission Directorate, Washington. “Innovative proposals like these will help us better understand our solar system and the universe.”

Five Explorer Mission proposals were selected from 22 submitted in February. Each team will receive $1 million to conduct an 11-month mission concept study. Mission costs are capped at $200 million each, excluding the launch vehicle. In addition, one Explorer Mission proposal was selected for technology development and will receive $600,000. Five Mission of Opportunity proposals were selected from 20 submissions. Each will receive $250,000 to conduct an 11-month implementation concept study. Mission costs are capped at $55 million each.

Following the detailed mission concept studies, NASA plans to select up to two of the Explorer Mission proposals and one or more of the five Mission of Opportunity proposals in February 2013. The missions would then proceed toward flight and some could launch by 2016.

The selected Explorer Mission proposals are:

-Ionospheric Connection Explorer (ICON) Thomas Immel, Principal Investigator (PI), University of California, Berkeley — The mission would fly instruments to understand the extreme variability in our Earth’s ionosphere, which can interfere with communications and geopositioning signals.

-Fast INfrared Exoplanet Spectroscopy Survey Explorer (FINESSE) Mark Swain, PI, Jet Propulsion Laboratory, Pasadena, Calif. — This proposal would use a space telescope to survey more than 200 planets around other stars. This would be the first mission dedicated to finding out what comprises exoplanet atmospheres, what conditions or processes are responsible for their composition, and how our solar system fits into the larger family of planets.

-Observatory for Heteroscale Magnetosphere-Ionosphere Coupling (OHMIC) James Burch, PI, Southwest Research Institute, San Antonio — The mission would use a pair of spacecraft flying in formation to study the processes that provide energy to power space weather storms. These storms create auroras and other electromagnetic activity that can impact orbiting spacecraft operations.

-Transiting Exoplanet Survey Satellite (TESS) George Ricker, PI, Massachusetts Institute of Technology, Cambridge, Mass. — Using an array of telescopes, TESS would perform an all-sky survey to discover transiting exoplanets, ranging from Earth-sized to gas giants, in orbit around the nearest and brightest stars in the sky. The mission’s primary goal would be to identify terrestrial planets in the habitable zones of nearby stars.

-Atmosphere-Space Transition Region Explorer (ASTRE) Robert Pfaff Jr., PI, NASA’s Goddard Space Flight Center, Greenbelt, Md. — The mission would study the interaction between the Earth’s atmosphere and the ionized gases of space. By flying excursions deep into the Earth’s upper atmosphere, its measurements would improve satellite drag models and show how space-induced currents in electric power grids originate and evolve with time.

The selected Explorer Mission of Opportunity proposals are:

-Global-scale Observations of the Limb and Disk (GOLD) Richard Eastes, PI, University of Central Florida, Orlando — This would involve an imaging instrument that would fly on a commercial communications satellite in geostationary orbit to image the Earth’s thermosphere and ionosphere.

-Neutron star Interior Composition ExploreR (NICER) Keith Gendreau, PI, Goddard — This mission would place an X ray timing instrument on the International Space Station (ISS) to explore the exotic states of matter within neutron stars and reveal their interior and surface compositions.

-Coronal Physics Investigator (CPI) John Kohl, PI, Smithsonian Astrophysical Observatory, Cambridge — A solar telescope would be mounted on the ISS to investigate the processes that produce the sun’s fast and slow solar wind.

-Gal/Xgal U/LDB Spectroscopic/Stratospheric THz Observatory (GUSSTO) Christopher Walker, PI, University of Arizona, Tucson — This mission would launch a high altitude balloon with a one-meter telescope to provide a comprehensive understanding of the inner workings of our Milky Way galaxy and one of our galaxy’s companion galaxies, the Large Magellanic Cloud.

-Ion Mass Spectrum Analyzer for SCOPE (IMSA), Lynn Kistler PI, University of New Hampshire, Durham — This partner mission of opportunity would provide a composition instrument to the Japanese cross-Scale Coupling in the Plasma universE (SCOPE) mission. SCOPE will study fundamental space plasma processes including particle acceleration, magnetic reconnection, and plasma turbulence.

The proposal selected for technology development funding is:

-The Exoplanetary Circumstellar Environments and Disk Explorer (EXCEDE), Glenn Schneider, PI, University of Arizona, Tucson – The technology development effort will enable studies of the formation, evolution, and architectures of exoplanetary systems through direct imaging.

The Explorer program is the oldest continuous program at NASA. It is designed to provide frequent, low-cost access to space using PI-led space science investigations relevant to the agency’s astrophysics and heliophysics programs. Initiated with the Explorer 1 launch in 1958 that discovered the Earth’s radiation belts and including the Cosmic Background Explorer mission that led to Nobel prizes for their investigators, the Explorer program has launched more than 90 missions. It is managed by Goddard for NASA’s Science Mission Directorate in Washington.

For more information about the Explorer program, visit: http://explorers.gsfc.nasa.gov .

NASA’s Jet Propulsion Laboratory is a division of the California Institute of Technology in Pasadena.

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Image of the Week: Rare Martian Lake Delta Spotted by Mars Express

28/09/2011

09.28.11 – via UKSpaceAgency: Europe’s Mars Express has spotted a rare case of a crater once filled by a lake, revealed by the presence of a delta. The delta is an ancient fan-shaped deposit of dark sediments, laid down in water. It is a reminder of Mars’ past, wetter climate.

Holden crater (left) and Eberswalde crater (right). Credits: ESA/DLR/FU Berlin (G. Neukum).
Holden crater (left) and Eberswalde crater (right).
Credits: ESA/DLR/FU Berlin (G. Neukum).

The delta is in the Eberswalde crater, in the southern highlands of Mars. The 65 km-diameter crater is visible as a semi-circle on the right of the image and was formed more than 3.7 billion years ago when an asteroid hit the planet. The rim of the crater is intact only on its right-hand side. The rest appears only faintly or is not visible at all. A later impact created the 140 km diameter Holden crater that dominates the centre and left side of the image. The expulsion of large amounts of material from that impact buried parts of Eberswalde.

However, within the visible part of Eberswalde, the delta and its feeder channels are well preserved, as seen near the top right of the crater. The delta covers an area of 115 square kilometres. Small, meandering feeder channels are visible towards the top of the crater, which would have filled it to form a lake.

Eberswalde crater in perspective. Credits: ESA/DLR/FU Berlin (G. Neukum).
Eberswalde crater in perspective.
Credits: ESA/DLR/FU Berlin (G. Neukum).

After the deposition of the delta sediments in the crater’s ancient lake, fresher sediments accumulated to cover up a major part of both the channels and the delta. These secondary sediments, presumably deposited by the wind, were later eroded in the delta area, exposing an inverted relief of the delta structure.

This delta structure, first identified with NASA’s Mars Global Surveyor spacecraft, is characteristic of the presence of a lake in the crater at that time. Such features provide a clear indication that liquid water flowed across the surface of Mars in the planet’s early history.

UK involvement in Mars Express is funded by the UK Space Agency. More information can be found in the missions section of the website.

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New Video Reveals Giant Asteroid Vesta as Seen by Spacecraft

21/09/2011

Mon, 19 Sep 2011 00:00 CDT via Space.com – A new video from a NASA spacecraft takes viewers on a flyover journey of Vesta, the second-largest object in the main asteroid belt between Mars and Jupiter.

Scientists constructed the two-minute video from images taken by NASA’s Dawn probe, which has been orbiting Vesta since July.

In addition to giving armchair astronomers around the world a great look at Vesta, the video should help scientists better understand the forces that shaped the massive space rock, researchers said.

In the video, the 330-mile (530-kilometer) Vesta is not entirely lit up; its northern latitudes are shrouded in darkness. That’s because the giant asteroid Vesta has seasons just like Earth, researchers said.It is currently winter in the Vestan north, and the north pole is in perpetual darkness.

A huge southern crater

The video highlights a huge circular depression several hundred miles wide near Vesta’s south pole. NASA’s Hubble Space Telescope first spotted this feature years ago, and scientists have been eager to get a better look at it ever since.

The cliffs of this massive depression rise several miles up from its floor, and a 9-mile (15-km) high mountain rises from the structure’s base, researchers said.

Researchers have used Dawn‘s images to determine Vesta’s rotational axis and to map out a system of latitude and longitude. The team defined the asteroid’s zero-longitude line, or prime meridian, using a small crater they named “Claudia,” after a Roman woman who lived in the second century B.C.

Vesta took its name from the Roman goddess of the hearth, home and family. Craters on the space rock will be named after the vestal virgins – priestesses of the goddess – and famous Roman women, researchers said. Other features will take the names of towns and festivals of ancient Rome.

Sharper images coming soon

Dawn captured the new images used in the video while it was still about 1,700 miles (2,700 km) above Vesta’s surface. The spacecraft is slated to move down to a lower orbit in October, from which it should be able to snap even closer photos, with a resolution about eight times higher, researchers said.

The $466 million Dawn spacecraft launched in September 2007 and entered orbit around Vesta on July 15 of this year. Next July, it will head off to study Ceres, the largest object in the asteroid belt. At 590 miles (950 km) across, Ceres is so large that astronomers consider it a dwarf planet. [Meet the Solar System’s Dwarf Planets]

Dawn is expected to reach Ceres in February 2015. The probe’s observations should allow scientists to compare the dwarf planet to Vesta. Unlike the drier and more evolved Vesta, Ceres is considered to be more primitive and wet, possibly harboring water ice, researchers have said.

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Zooming in on Earth – Amazing Time-Lapse Video From International Space Station

19/09/2011

Wouldn’t anyone want the chance to see it for themselves with their own eyes?

Well I guess its possible if you have at least a cool million dollars to spend on the new Soviet Space Hotel.

That or perhaps alien abduction.

But what do I know?

Take me to your leader.  I’m tired of ours.

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Extra Energy Can Have a Big Effect on Earth – Secret Lives of Solar Flares

19/09/2011

Sept. 19, 2011 via NASAScience: One hundred and fifty two years ago, a man in England named Richard Carrington discovered solar flares.

Secret Lives (sunspots, 200px)

Sunspots sketched by
R. Carrington on Sept. 1, 1859.
© R. Astronomical Society.

[more]

It happened at 11:18 AM on the cloudless morning of Thursday, September 1st, 1859. Just as usual on every sunny day, the 33-year-old solar astronomer was busy in his private observatory, projecting an image of the sun onto a screen and sketching what he saw. On that particular morning, he traced the outlines of an enormous group of sunspots. Suddenly, before his eyes, two brilliant beads of white light appeared over the sunspots; they were so bright he could barely stand to look at the screen.

Carrington cried out, but by the time a witness arrived minutes later, the first solar flare anyone had ever seen was fading away.

It would not be the last. Since then, astronomers have recorded thousands of strong flares using instruments ranging from the simplest telescopes in backyard observatories to the most complex spectrometers on advanced spacecraft.  Possibly no other phenomenon in astronomy has been studied as much.

After all that scrutiny, you might suppose that everything about solar flares would be known.  Far from it.  Researchers recently announced that solar flares have been keeping a secret.

“We’ve just learned that some flares are many times stronger than previously thought,” says University of Colorado physicist Tom Woods who led the research team. “Solar flares were already the biggest explosions in the solar system—and this discovery makes them even bigger.”

Secret Lives (splash, 558px)

Click to view a ScienceCast video about the late phase of solar flares. [Youtube]

NASA’s Solar Dynamics Observatory (SDO), launched in February 2010, made the finding:  About 1 in 7 flares experience an “aftershock.”  About ninety minutes after the flare dies down, it springs to life again, producing an extra surge of extreme ultraviolet radiation.

“We call it the ‘late phase flare,’” says Woods.   “The energy in the late phase can exceed the energy of the primary flare by as much as a factor of four.”

What causes the late phase? Solar flares happen when the magnetic fields of sunspots erupt—a process called “magnetic reconnection.”  The late phase is thought to result when some of the sunspot’s magnetic loops re-form.  A diagram prepared by team member Rachel Hock of the University of Colorado shows how it works.

The extra energy from the late phase can have a big effect on Earth.  Extreme ultraviolet wavelengths are particularly good at heating and ionizing Earth’s upper atmosphere.  When our planet’s atmosphere is heated by extreme UV radiation, it puffs up, accelerating the decay of low-orbiting satellites.  Furthermore, the ionizing action of extreme UV can bend radio signals and disrupt the normal operation of GPS.

SDO was able to make the discovery because of its unique ability to monitor the sun’s extreme UV output in high resolution nearly 24 hours a day, 7 days a week.  With that kind of scrutiny, it’s tough to keep a secret–even one as old as this.

The original research of Woods et al may be found in the Oct. 1, 2011, issue of the Astrophysical Journal.

Author: Dr. Tony Phillips | Credit: Science@NASA

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