Tag Archive for "Bob Eklund Column"

NASA New Horizons “Phones Home” Safe after Pluto Flyby

Posted by :reta On : July 20, 2015

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Tags:Bob Eklund Column, Johns Hopkins Univedrsity, NASA, New Horizons Satelitte, Pluto, Southwest Research Institute

Note: Based on press releases from NASA, Johns Hopkins University Applied Physics Laboratory, and Southwest Research Institute.

NASA’s New Horizons “Phones Home” Safe after Pluto Flyby

Close up images of region near Pluto’s equator reveal a giant surprise: a range of youthful mountains rising as high at 11,000 feet above the surface of the icy body.

The call everyone was waiting for is in. NASA’s New Horizons spacecraft phoned home just before 9 p.m. EDT Tuesday, July 14, to tell the mission team and the world it had accomplished the historic first-ever flyby of Pluto.

“I know today we’ve inspired a whole new generation of explorers with this great success, and we look forward to the discoveries yet to come,” NASA Administrator Charles Bolden said. “This is an historic win for science and for exploration. We’ve truly, once again, raised the bar of human potential.”

The preprogrammed “phone call”–a 15-minute series of status messages beamed back to mission operations at the Johns Hopkins University Applied Physics Laboratory in Maryland through NASA’s Deep Space Network–ended a very suspenseful 21-hour waiting period. New Horizons had been instructed to spend the day gathering the maximum amount of data, and not communicating with Earth until it was beyond the Pluto system.

Pluto is the first Kuiper Belt object visited by a mission from Earth. New Horizons will continue on its adventure deeper into the Kuiper Belt where thousands of objects hold frozen clues as to how the solar system formed.

New Horizons is collecting so much data it will take 16 months to send it all back to Earth.

PLUTO’S ICY MOUNTAINS. Close-up images of a region near Pluto’s equator reveal a giant surprise: a range of youthful mountains rising as high as 11,000 feet above the surface of the icy body.

The mountains likely formed no more than 100 million years ago–mere youngsters relative to the 4.56-billion-year age of the solar system–and may still be in the process of building, says Jeff Moore of New Horizons’ Geology, Geophysics and Imaging Team (GGI). That suggests the close-up region, which covers less than one percent of Pluto’s surface, may still be geologically active today.

Moore and his colleagues base the youthful age estimate on the lack of craters in this scene. Like the rest of Pluto, this region would presumably have been pummeled by space debris for billions of years and would have once been heavily cratered—unless recent activity had given the region a facelift, erasing those pockmarks.

“This is one of the youngest surfaces we’ve ever seen in the solar system,” says Moore.

Unlike the icy moons of giant planets, Pluto cannot be heated by gravitational interactions with a much larger planetary body. Some other process must be generating the mountainous landscape.

The mountains are probably composed of Pluto’s water-ice “bedrock.”

Although methane and nitrogen ice covers much of the surface of Pluto, these materials are not strong enough to build the mountains. Instead, a stiffer material, most likely water-ice, created the peaks. “At Pluto’s temperatures, water-ice behaves more like rock,” said deputy GGI lead Bill McKinnon of Washington University, St. Louis.

The close-up image was taken about 1.5 hours before New Horizons closest approach to Pluto, when the craft was 478,000 miles from the surface of the planet. The image easily resolves structures smaller than a mile across.

NASA TV schedules, satellite coordinates, and links to streaming video:
http://www.nasa.gov/nasatv

The public can follow the path of the spacecraft in coming days in real time with a visualization of the actual trajectory data, using NASA’s online Eyes on Pluto (http://eyes.nasa.gov/pluto).

Eyeing Up Earth-Like Planets

Posted by :reta On : July 9, 2015

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Category: Looking Up Column

Tags:Astronomers, Bob Eklund, Bob Eklund Column, James Webb Space Telescope, Looking Up, Royal Academy of Science

Based on a press release from United Kingdom Royal Astronomical Society (RAS).

Almost 2,000 exoplanets have been discovered to date, ranging from rocky Earth-like planets to hot Jupiters, and orbiting every type of star. But how many of these distant worlds are habitable? Today’s technology means that we currently have very little information about what exoplanets are like beyond their presence, size and distance from star.

With the launch of the James Webb Space Telescope (JWST), http://www.jwst.nasa.gov), we may have our first glimpses into atmospheres of Earth-like exoplanets, according to the results of a study by Dr. Joanna Barstow, presented at the British National Astronomy Meeting in Llandudno, Wales, UK, on Wednesday, July 8.

“A planet’s atmosphere provides a good guide to likely conditions on the surface,” said Barstow, of the University of Oxford. “The Earth’s atmosphere contains significant amounts of nitrogen, oxygen, ozone and water. By contrast, its inhospitable ‘evil twin,’ Venus, has an atmosphere made mostly of carbon dioxide, which drives its surface temperature to a blistering 450 degrees Celsius.”

A successor to the Hubble Space Telescope, JWST is due for launch in 2018 and will study the universe in infrared wavelengths. Barstow’s study shows that JWST may be able to differentiate between a planet with a clement, Earth-like atmosphere, and one with more hostile conditions such as are found on our neighboring planet Venus. JWST will have the capability to detect key markers that could indicate the presence of a climate like our own when looking at Earth-size planets around stars that are smaller and redder than

NASA’s Webb Sunshield Stacks Up To Test! The Sunshield on NASA’s James Webb Space Telescope is the largest part of the observatory’s five layers of thin membrane that must unfurl reliably in space to precise tolerances. Recently, engineers stacked and unfurled a full-sized test unit of the Sunshield and it worked perfectly.

Different gases have already been identified successfully in the atmospheres of several large, hot, Jupiter-size planets by studying tiny variations in the starlight that passes through their atmospheres when they cross in front of their parent stars. However, these variations are minuscule: the light filtered through the exoplanet’s atmosphere is one ten-thousandth of the total starlight detected. Studying planets the size of the Earth is an even greater challenge. Although JWST would struggle with analyzing a solar system exactly like our own, it would be capable of studying Earth-like planets around cooler stars—if such a system were to be found.

“If we took the Earth and Venus, and placed them in orbit around a cool, red star that’s not too far away, our study shows that JWST could tell them apart. Earth’s ozone layer, 10 kilometers above the surface, is produced when light from the Sun interacts with molecules of oxygen in our atmosphere, and it produces an unmistakable signal that could be detected by JWST. Venus, without a substantial ozone layer, would look very different,” said Barstow. “That’s assuming that planets starting out like Earth and Venus would evolve in the same way around a cool star!”

However, JWST will be used for a wide range of astronomical applications, not just detecting exoplanets, and securing time on the telescope will be highly competitive. To make these detections, astronomers would need to observe the exoplanets at least 30 times, taking valuable telescope time.

“Future telescopes that are dedicated to observing the atmospheres of many rocky planets around different stars will be required to fully resolve the question of habitability on exoplanets. In the meantime, JWST will observe many other weird and wonderful planets in unprecedented detail,” said Barstow.

Spacecraft Plans Encounter with Pluto; You Can See At Observatory

Posted by :reta On : June 28, 2015

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Category: Bob Eklund Column

Tags:Bob Eklund Column, City, LORRI, NASA, Pluto

Based on article from Astronomy Now magazine and press release from Griffith Observatory.

New Horizons Spacecraft Prepares for Encounter with Pluto July 14

In a long series of images obtained by New Horizons’ telescopic Long Range Reconnaissance Imager (LORRI) between May 29 and June 19, Pluto and its largest moon, Charon, appear to more than double in size. From this rapidly improving imagery, scientists on the New Horizons team have found that the “close approach hemisphere” on Pluto that New Horizons will fly over has the greatest variety of terrain types seen on the planet so far. They have also discovered that Charon has a “dark pole”—a mysterious dark region that forms a kind of anti-polar cap.

“This system is just amazing,” said Alan Stern, New Horizons Principal Investigator, from the Southwest Research Institute, Boulder, Colorado. “The science team is just ecstatic with what we see on Pluto’s close approach hemisphere: Every terrain type we see on the planet—including both the brightest and darkest surface areas—are represented there, it’s a wonderland!

“And about Charon—wow—I don’t think anyone expected Charon to reveal a mystery like dark terrains at its pole,” he continued. “Who ordered that?”

“The unambiguous detection of bright and dark terrain units on both Pluto and Charon indicates a wide range of diverse landscapes across the pair,” said science team co-investigator and imaging lead Jeff Moore, of NASA Ames Research Center, Mountain View, California. “For example, the bright fringe we see on Pluto may represent frost deposited from an evaporating polar cap, which is now in summer sun.”

GRIFFITH OBSERVATORY TO CELEBRATE FIRST ENCOUNTER WITH PLUTO.
On July 14, after a journey of 10 years and three billion miles, NASA’s New Horizons spacecraft will make the first-ever close encounter with Pluto. What can we expect from New Horizons as it ventures past the mysterious dwarf planet? A good way to find out is to come to Los Angeles’ Griffith Observatory, which will host several activities to celebrate the New Horizons encounter with Pluto. All events are free and open to the public.

WHEN: Tuesday, July 14, 2015 — LIVE PLUTO FLYBY
* 1:00 – 5:00 p.m. PDT: Twenty-minute talks on Pluto and New Horizons, presented hourly
* 5:00 – 7:00 p.m. PDT: NASA-TV coverage of the New Horizons flyby with commentary by Griffith Observatory staff
* 6:02 p.m. PDT: Signal from New Horizons confirms the spacecraft’s safe passage through the Pluto system
* 7:30 – 8:30 p.m. PDT: Presentation by Griffith Observatory staff about the New Horizons mission and recap of the evening’s events (Streamed live on GriffithTV)
* 10:00 p.m. PDT: Observatory and Griffith Park close as usual

Friday, July 17, 2015 — ALL PLUTO CONSIDERED
* 7:30 – 8:45 p.m. PDT: Griffith Observatory Curator Dr. Laura Danly and Griffith Observatory Director Dr. E. C. Krupp show the latest images of Pluto from New Horizons and illustrate Pluto’s impact on culture from its discovery until now. (Streamed live on GriffithTV)

WHERE: Griffith Observatory, Leonard Nimoy Event Horizon Theater, 2800 East Observatory Road, Los Angeles, California 90027

Seating is first-come, first-served, up to the capacity of the theater. For more information visit http://www.griffithobservatory.org or call (213) 473-0800.

Select activities will be streamed live on GriffithObservatoryTV. For video, schedules, and downlink information visit http://new.livestream.com/GriffithObservatoryTV

Contact:
Bonnie Winings
Friends of the Observatory
+1 (213) 473-0879, +1 (818) 621-2434
bwinings@friendsoftheobservatory.org

Images & Links:
http://astronomynow.com/wp-content/uploads/2015/06/NH_LORRI_OP4_mid-June_v3_PLUTO.jpg
http://www.griffithobservatory.org/events/Pluto_Events_2015.html

Update “Spaces” with Bob

Posted by :reta On : June 16, 2015

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Category: Bob Eklund Column

Tags:Bob Eklund Column

Update invited Bob Eklund, who is a columnist for other news services, to be a visiting columnist. Most of his columns are out of sight—well, about things out of sight, at least to the naked eye.

(Photo courtesy of Aaron Dominquez.)
Bob with his wife Laura and their telescope.

For many years Bob has helped the Mount Wilson Observatory in California with its public outreach programs. He is the author of a book of poetry about astronomy, First Star I See Tonight: An Exploration of Wonder. His column, “Looking Up,” appears weekly in several Southern California newspapers. He is also the AstroPoetry Blog editor for the international astronomy outreach organization Astronomers Without Borders.

Looking Up
by Bob Eklund

Based on press release from JPL.

New images of dwarf planet Ceres, taken by NASA’s Dawn spacecraft, show the cratered surface of this mysterious world—including its mysterious “bright spots”—in sharper detail than ever before. These are among the first snapshots from Dawn’s second mapping orbit, which is 2,700 miles above Ceres.

The region with the brightest spots is in a crater about 55 miles across. The spots consist of many individual bright points of differing sizes, with a central cluster. So far, scientists have found no obvious explanation for their observed locations or brightness levels.

“The bright spots in this configuration make Ceres unique from anything we’ve seen before in the solar system,” said Chris Russell, principal investigator for the Dawn mission based at UCLA. “The science team is working to understand their source. Reflection from ice is the leading candidate in my mind, but the team continues to consider alternate possibilities, such as salt. With closer views from the new orbit and multiple view angles, we soon will be better able to determine the nature of this enigmatic phenomenon,”

Numerous other features on Ceres intrigue scientists, as they contrast this world with others—including protoplanet Vesta, which Dawn visited for 14 months in 2011 and 2012. Craters abound on both bodies, but Ceres appears to have had more activity on its surface, with evidence of flows, landslides and collapsed structures.

Additionally, new images from Dawn’s visible and infrared mapping spectrometer (VIR) show a portion of Ceres’ cratered northern hemisphere, taken on May 16, including a true-color view and a temperature image. The temperature image is derived from data in the infrared light range. This instrument is also important in determining the nature of the bright spots.

Having arrived in its current orbit on June 3, Dawn will observe the dwarf planet from 2,700 miles above its surface until June 28. In orbits of about three days each, the spacecraft will conduct intensive observations of Ceres. It will then move toward its next orbit of altitude 900 miles, arriving in early August.

The Dawn mission has achieved several important “firsts” in space exploration. It is the only spacecraft ever to orbit two destinations beyond Earth and the only to orbit an object in the main asteroid belt between Mars and Jupiter. The giant protoplanet Vesta was confirmed to be a fascinating world more closely related to the terrestrial planets (including Earth) than to typical asteroids. Dwarf planet Ceres, larger yet less dense, is believed to have a large amount of ice and may even have subsurface liquid water. Ceres was the first dwarf planet discovered and Dawn is now studying it in detail.

Dawn’s mission is managed by JPL for NASA’s Science Mission Directorate in Washington. Dawn is a project of the directorate’s Discovery Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, Max Planck Institute for Solar System Research, Italian Space Agency and Italian National Astrophysical Institute are international partners on the mission team.

More information about Dawn is available at the following sites:
http://dawn.jpl.nasa.gov

Dawn

NASA New Horizons “Phones Home” Safe after Pluto Flyby

Eyeing Up Earth-Like Planets

Spacecraft Plans Encounter with Pluto; You Can See At Observatory

Update “Spaces” with Bob

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