Category Archives: Space Systems

Exoplanets, Space Systems

Video: Update on the Kepler exoplanet search

The Kepler space observatory was thought to be out of the exoplanet finding business for good due to a failure in the guidance hardware.  However, the system was returned to action using a clever technique with solar light pressure to maintain the telescope’s pointing stability. The K2 Mission, as this new phase of operation is called, has been underway for sometime now. This SETI Institute seminar gives an update

The NASA K2 mission makes use of the Kepler spacecraft to expand upon Kepler’s groundbreaking discoveries in the fields of exoplanets and astrophysics through new and exciting observations. K2 uses an innovative way of operating the spacecraft by carefully balancing the pressure of photons coming from the Sun. The K2 mission offers long-term, simultaneous optical observation of thousands of objects at high precision. Ecliptic fields are observed for approximately 75-days enabling a unique exoplanet survey which fills the gaps in duration and sensitivity between the Kepler and TESS missions, and offers exoplanet target identification for JWST transit spectroscopy. Astrophysics observations with K2 include studies of young open clusters such as the Pleiades and Hyades, galaxies, supernovae, and galactic archeology.

See the Kepler Science Center for more about the K2 mission.

Living in Space, Space Systems, SpaceCasts

Video: ‘Space to Ground’ report about the ISS – Aug.28.15

Here’s the latest report from NASA on activities related to the Int. Space Station:

Asteroids & Comets, Space Science, Space Systems

Dawn probe sends sharpest images yet of Ceres

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The Dawn Mission posts new and sharper images of the Ceres dwarf planet in the asteroid belt:

Dawn Sends Sharper Scenes from Ceres

The closest-yet views of Ceres, delivered by NASA’s Dawn spacecraft, show the small world’s features in unprecedented detail, including Ceres’ tall, conical mountain; crater formation features and narrow, braided fractures.

The Lonely Mountain 

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NASA’s Dawn spacecraft spotted this tall, conical mountain on Ceres from a distance of 915 miles (1,470 kilometers). The mountain, located in the southern hemisphere, stands 4 miles (6 kilometers) high. Its perimeter is sharply defined, with almost no accumulated debris at the base of the brightly streaked slope with bright streaks. The image was taken on August 19, 2015. The resolution of the image is 450 feet (140 meters) per pixel. Full res jpeg.
“Dawn is performing flawlessly in this new orbit as it conducts its ambitious exploration. The spacecraft’s view is now three times as sharp as in its previous mapping orbit, revealing exciting new details of this intriguing dwarf planet,” said Marc Rayman, Dawn’s chief engineer and mission director, based at NASA’s Jet Propulsion Laboratory, Pasadena, California.

At its current orbital altitude of 915 miles (1,470 kilometers), Dawn takes 11 days to capture and return images of Ceres’ whole surface. Each 11-day cycle consists of 14 orbits. Over the next two months, the spacecraft will map the entirety of Ceres six times.

Urvara Peaks

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NASA’s Dawn spacecraft took this image that shows a mountain ridge, near lower left, that lies in the center of Urvara crater on Ceres. Urvara is an Indian and Iranian deity of plants and fields. The crater’s diameter is 101 miles (163 kilometers). This view was acquired on August 19, 2015, from a distance of 915 miles (1,470 kilometers). The resolution of the image is 450 feet (140 meters) per pixel. Full res jpeg.
The spacecraft is using its framing camera to extensively map the surface, enabling 3-D modeling. Every image from this orbit has a resolution of 450 feet (140 meters) per pixel, and covers less than 1 percent of the surface of Ceres.

At the same time, Dawn’s visible and infrared mapping spectrometer is collecting data that will give scientists a better understanding of the minerals found on Ceres’ surface.

Gaue Crater

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NASA’s Dawn Spacecraft took this image of Gaue crater, the large crater on the bottom, on Ceres. Gaue is a Germanic goddess to whom offerings are made in harvesting rye. The center of this crater is sunken in. Its diameter is 84 kilometers (52 miles). The resolution of the image is 450 feet (140 meters) per pixel. The image was taken from a distance of 915 miles (1,470 kilometers) on August 18, 2015. Full res jpeg.
Engineers and scientists will also refine their measurements of Ceres’ gravity field, which will help mission planners in designing Dawn’s next orbit — its lowest — as well as the journey to get there. In late October, Dawn will begin spiraling toward this final orbit, which will be at an altitude of 230 miles (375 kilometers).

Dawn is the first mission to visit a dwarf planet, and the first to orbit two distinct solar system targets. It orbited protoplanet Vesta for 14 months in 2011 and 2012, and arrived at Ceres on March 6, 2015.

Topographic Maps of Ceres’ East and West Hemispheres

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This pair of images shows color-coded maps from NASA’s Dawn mission, revealing the highs and lows of topography on the surface of dwarf planet Ceres. The map at left is centered on terrain at 60 degrees east longitude; the map at right is centered on 240 degrees east longitude. The color scale extends about 5 miles (7.5 kilometers) below the surface in indigo to 5 miles (7.5 kilometers) above the surface in white. The topographic map was constructed from analyzing images from Dawn’s framing camera taken from varying sun and viewing angles. The map was combined with an image mosaic of Ceres and projected as an orthographic projection. The well-known bright spots in the center of Ceres northern hemisphere in the image at right retain their bright appearance, although they are color-coded in the same green elevation of the crater floor in which they sit. Full res jpeg.
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. For a complete list of mission participants, visit: dawn.jpl.nasa.gov/mission

More information about Dawn is available at the following sites:

Living in Space, Space Systems, SpaceCasts

Video: ‘Space to Ground’ report on ISS – Aug.21.15

Here’s the latest NASA Space to Ground weekly report on activities related to the Int. Space Station:

Pluto and beyond, Space Science, Space Systems

New Horizons: Fly-by video + The source of Pluto’s nitrogen

Here’s a video showing the view of Pluto as the New Horizon probe flew past it:

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I missed this posting from New Horizons last week:

Scientists Study Nitrogen Provision for Pluto’s Atmosphere

The latest data from NASA’s New Horizons spacecraft reveal diverse features on Pluto’s surface and an atmosphere dominated by nitrogen gas. However, Pluto’s small mass allows hundreds of tons of atmospheric nitrogen to escape into space each hour.

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Mission scientists are studying New Horizons data to discover what’s pumping up the nitrogen in Pluto’s atmosphere, even as it escapes into interplanetary space. This enhanced color image – created from four images from New Horizons’ Long Range Reconnaissance Imager (LORRI) combined with color data from the spacecraft’s Ralph instrument – helps scientists detect differences in the composition and texture of Pluto’s surface. The data hint that Pluto may still be geologically active, a theory that could explain how Pluto’s escaping atmosphere remains flush with nitrogen. Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute. (Larger image.)
So where does all this nitrogen come from? Kelsi Singer, a postdoctoral researcher at Southwest Research Institute, and her mentor Alan Stern, New Horizons principal investigator and SwRI associate vice president, outlined likely sources in a paper titled, “On the Provenance of Pluto’s Nitrogen.” The Astrophysical Journal Letters accepted the paper for publication on July 15, just a day after the spacecraft’s closest encounter with the icy dwarf planet.

“More nitrogen has to come from somewhere to resupply both the nitrogen ice that is moving around Pluto’s surface in seasonal cycles, and the nitrogen that is escaping off the top of the atmosphere as the result of heating by ultraviolet light from the Sun,” said Singer.

Singer and Stern looked at a number of different ways that nitrogen might be resupplied. They wondered if comets could deliver enough nitrogen to Pluto’s surface to resupply what is escaping its atmosphere. They also looked at whether craters made by the comets hitting the surface could excavate enough nitrogen – but that would require a very deep layer of nitrogen ice at the surface, which is not proven. The team also studied whether craters could expose more surface area, by punching through surface deposits that would likely be built up over time.

“We found that all of these effects, which are the major ones from cratering, do not seem to supply enough nitrogen to supply the escaping atmosphere over time,” continued Singer. “While it’s possible that the escape rate was not as high in the past as it is now, we think geologic activity is helping out by bringing nitrogen up from Pluto’s interior.”

And while the data weren’t in before this paper was written, the newest images of Pluto show land forms that suggest heat is rising beneath the surface, with troughs of dark matter either collecting, or bubbling up, between flat segments of crust, which could be related.

“Our pre-flyby prediction, made when we submitted the paper, is that it’s most likely that Pluto is actively resupplying nitrogen from its interior to its surface, possibly meaning the presence of ongoing geysers or cryovolcanism,” said Stern. “As data from New Horizons comes in, we will be very interested to see if this proves true.”

New Horizons is part of NASA’s New Frontiers Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Ala. The Johns Hopkins University Applied Physics Laboratory in Laurel, Md., designed, built, and operates the New Horizons spacecraft and manages the mission for NASA’s Science Mission Directorate. SwRI leads the science mission, payload operations, and encounter science planning.