Archive for August, 2017

On the prowl, NASA’s NEOWISE telescope.
Credit: NASA/JPL

 

It’s crowded out there…

With origins in the Oort Cloud – a group of icy bodies beginning roughly 300 billion kilometers away from the Sun – have periods of thousands or even millions of years.

A team of astronomers report that large, distant comets are more common than previously thought. In fact, the researchers found that about seven times more long-period comets measuring at least one kilometer across exist than previously thought.

NEOWISE data

Using data from NASA’s Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) space telescope mission, the elusive long period comet population has been studied.

Using NEOWISE, an eight month survey indicated that the number of long-period comets passing within 1.5 AU (1.5 times the distance from the Sun to Earth) is a factor of several higher than previous estimates, while Jupiter family comets are within the previous range of estimates of a few thousand down to sizes near 1.3 km in diameter.

Illustration shows how scientists used data from NASA’s WISE spacecraft to determine the nucleus sizes of comets. They subtracted a model of how dust and gas behave in comets in order to obtain the core size.
Credit: NASA/JPL-Caltech

Higher than expected

“The number of long-period comets seen in the NEOWISE was higher than expected from previous estimates, which means that there are seven times more Oort Cloud objects around our solar system than Dutch astronomer Jan Oort predicted in 1950,” said study participant, Tommy Grav of the Tucson, Arizona-based Planetary Science Institute in a press statement.

The Oort Cloud is thought to be a population of small icy bodies spherically distributed on the outermost edge of our Solar System. They are too distant to be observed by current telescopes.

These icy bodies can be disturbed by passing stars, galactic tides, or collisions, causing them to be perturbed inwards where they appear as long-period comets.

Credit: NASA History Office

NASA has a long tradition of interacting closely with and inviting advice from the scientific community, which is integral to the culture of its scientific programs.

In a newly published monograph, Science Advice to NASA: Conflict, Consensus, Partnership, Leadership, the author, Joseph Alexander, looks at two main sources of scientific advice: the NASA Advisory Committee structure and the National Academy of Sciences’ Space Studies Board.

As a former executive director of the latter organization, Joe Alexander is well-positioned to flesh out this subject from its roots in NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA), to the mid-2010s.

Useful lessons

Alexander’s assessments of NASA’s interactions with outside scientific advisors provide useful lessons for research managers, decision makers, and scientists.

Lastly, the author discusses the recurring characteristics of notably successful advisory activities and provides a glimpse of what past experience might imply for the future of scientific advice at NASA.

For your free download of this informative e-Book, go to:

https://www.nasa.gov/connect/ebooks/science_advice_to_nasa

Titan as imaged by Cassini spacecraft.
Credit: NASA/JPL-Caltech/Space Science Institute

 

Opening up Titan – a moon of Saturn – to robotic exploration is the thrust behind a proposal from the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland.

An APL team is proposing an instrumented, radioisotope-powered dual-quadcopter to explore Titan, one of a number of “ocean worlds” in our solar system that hold the ingredients for life.

Called Dragonfly, it is a NASA New Frontiers-class mission concept that APL is proposing.

Titan is known to be covered with rich organic material, which is undergoing chemical processes that might be similar to those on early Earth, before life developed.

Dragonfly dual-quadcopter, shown here in an artist’s rendering, could make multiple flights to explore diverse locations as it characterizes the habitability of Titan’s environment.
Credit: APL/Mike Carroll

Drone revolution

According to APL, while the idea of exploring Titan by rotorcraft is not new, technological developments in the last two decades — the “drone revolution” –have made such a mission more feasible.

Later this fall, NASA is expected to select a few of the New Frontiers mission proposals for further study.

Only one will be chosen for flight as the fourth mission in the planetary exploration program; the APL-led New Horizons mission to Pluto and the Kuiper Belt was the first New Frontiers mission ever selected.

Credit: APL/Mike Carroll

Final mission selection is expected in mid-2019.

Resources

For more information on Dragonfly, go to this informative website at:

http://dragonfly.jhuapl.edu/

Also, here’s a new video featuring APL’s Peter Bedini, program manager for Dragonfly, and he details the proposal’s engineering and science. Go to:

https://www.youtube.com/watch?v=mk1zVxwq7O4

Artist’s view of James Webb Space Telescope.
Credit: NASA

A new report by the National Academies of Sciences (NAS), Engineering, and Medicine has taken a look at NASA’s large strategic missions.

The message stemming from the report is that NASA should continue its large strategic missions to maintain United States’ global leadership in space.

But there’s a caveat. Controlling the costs of these large missions remains vital in order to preserve the overall stability of the program, the report finds.

Poster-child

To that point, concerns have been raised in the past about NASA’s large missions – a history of costs exceeding original estimates, impacting the overall budget of the agency.

For instance, the poster-child for escalating dollars and delays is the James Webb Space Telescope (JWST). This large mission experienced substantial cost growth.  Big jumps in costs for a mission can have an impact on the entire science program at NASA, the report explains. The total cost of JWST is roughly $10 billion and is to be launched in 2018.

In short, cost overruns in one space sector can influence projects large and small within NASA’s astrophysics, earth science, heliophysics, and planetary science portfolio.

The report adds that NASA is hoping to keep the now-orbiting Hubble Space Telescope operational until at least 2020 to allow for at least one year of overlap with the JWST.

NASA’s venerable Hubble Space Telescope – still carrying out sightseeing observations thanks to several servicing missions.
Credit: NASA

Up-scope!

The new report – under the wing of the NAS Space Science Board and authored by a Committee on Large Strategic NASA Science Missions: Science Value and Role in a Balanced Portfolio — underscores how best to identify in decadal surveys what goals are most desirable at different budget levels.

“This approach will allow NASA to develop, if needed, less expensive implementation strategies (known as ‘de-scoping’) for missions so that they do not exceed budget constraints that may arise in the future,” notes a NAS press statement on the report. “It could also identify opportunities to ‘up-scope’ such missions to perform greater science, should budgets and the program balance allow.”

New estimation tools

A report recommendation is that NASA should support the development of “new estimation tools” to perform robust cost estimates and risk assessment for future missions.

“New technologies will require new methods of estimating costs,” said Kathryn Thornton, committee co-chair and director of the aerospace engineering program at the University of Virginia, who also helped repair the Hubble Space Telescope during its first in-orbit servicing mission.

“Although NASA has gotten better at developing such tools, the agency will have to adapt its ways as technology evolves.”

As example, new technologies, like CubeSats, particularly in large constellations, “will require new methods of cost estimation, some of which are already being developed by industry,” the new report notes. While NASA has become better at estimating costs, “the agency will have to adapt its methods as technology evolves.”

To read the full report, Powering Science: NASA’s Large Strategic Science Missions, sponsored by NASA, go to:

https://www.nap.edu/download/24857#

Official SpaceX FORMOSAT-5 mission patch.

UpdateSuccessful launch, first stage booster return, satellite in orbit!

Today’s SpaceX’s Falcon 9 launch is set to deliver FORMOSAT-5, an Earth observation satellite for Taiwan’s National Space Organization (NSPO), to a low-Earth orbit (LEO).

Following stage separation, Falcon 9’s first stage will attempt to land on the “Just Read the Instructions” droneship that will be stationed in the Pacific Ocean

The 42-minute launch window opens on Thursday, August 24 at 11:51 a.m. PDT or 18:51 UTC. The booster will depart from Launch Complex 4 East (SLC-4E) at Vandenberg Air Force Base in California.

The SpaceX webcast of the launch will go live about 10 minutes before liftoff at:

http://www.spacex.com/webcast

 

The U.S. Air Force’s X-37B Orbital Test Vehicle 4 is seen after landing at NASA ‘s Kennedy Space Center Shuttle Landing Facility in Florida on May 7, 2017.
Credit: U.S. Air Force courtesy photo

X-37B mission

Assuredly, keeping a watchful eye on this SpaceX booster mission is the US Air Force and X-37B space plane officials.

Technicians are busily preparing the robotic X-37B Orbital Test Vehicle for the program’s fifth flight – OTV-5. This drone carries classified cargo and is reportedly scheduled to launch September 7 atop a SpaceX Falcon 9 from Kennedy Space Center, Florida.

This OTV-5 mission signals first time use of the SpaceX booster. Previous space plane missions have been boosted into Earth orbit by United Launch Alliance’s Atlas-5 launchers.

Go to this informative video from C4ISRNET:

http://www.c4isrnet.com/video/2017/08/23/spaceplane-readies-for-september-flight/

Curiosity Front Hazcam Left B image taken on Sol 1793, August 22, 2017.
Credit: NASA/JPL-Caltech

 

Now in Sol 1793, NASA’s Curiosity Mars rover experienced limited arm activities and a less lengthy weekend drive than planned, reports Abigail Fraeman, a planetary geologist at NASA/JPL in Pasadena, California.

Curiosity Mastcam Left image taken on Sol 1792, August 21, 2017.
Credit: NASA/JPL-Caltech/MSSS

Colder than expected

“Unfortunately, some of the arm activities and the drive we planned over the weekend didn’t execute because Mars was slightly colder than we expected,” Fraeman notes, “and we didn’t heat the actuators in the arm for quite long enough.”

 

 

Now planned is to recoup the contact science observations scientists had planned on sandy ripples in front of the robot.

Planned route

On tap is using Curiosity’s Mars Hand Lens Imager (MAHLI) to image targets “The Shivers,” “Trumpet,” and “Hosmer.”

Also slated is use of the Alpha Particle X-Ray Spectrometer (APXS) to observe Trumpet.

“Following the contact science activities, we’ll go for a drive that continues along the strategically planned route towards the area Curiosity will ascend Vera Rubin Ridge,” Fraeman adds.

Curiosity Mastcam Left image taken on Sol 1792, August 21, 2017.
Credit: NASA/JPL-Caltech/MSSS

 

 

Solar eclipses on Mars

Not to be outdone by yesterday’s solar eclipse, “solar eclipses happen on Mars too, although the Martian moons Phobos and Deimos are too small to completely cover the Sun like on Earth,” Fraeman explains.

Curiosity Mastcam Left image taken on Sol 1792, August 21, 2017.
Credit: NASA/JPL-Caltech/MSSS

“Curiosity has had the opportunity to observe several of these awesome celestial events throughout the mission, including one back in 2013 when even the rover couldn’t help but take a pause in the middle of a drive to look skyward,” Fraeman points out.

Here on Earth, Curiosity science team member Fred Calef’s unique pinhole viewer shows crescent shadows during yesterday’s eclipse.
Credit: Fred Calef

“Fortunately, with special solar filters already built into the rover’s cameras, Curiosity didn’t need to worry about ordering eclipse glasses last minute” in order to capture spectacular images.

 

Unidentified “box boy” is ready for eclipse action at one of the total solar eclipse viewing sites in Casper, Wyoming. This observer donned a cardboard box with eye-protective plastic to view the partial eclipse before totality.
Credit: Barbara David

CASPER, Wyoming – To paraphrase the legendary fighter, then Cassius Clay chiding his opponent, Sonny Liston, it was a celestial punch that was a true knockout – “a total eclipse of the Sunny!”

“It’s all about what the eclipse means to you, what it means to you and to you only,” and how personally it affects you, said John Goss, president of the Astronomical League that sponsored Astrocon 2017 here, in part a celebration of the total eclipse of the Sun.

During total eclipse, participants use their hands to observe crescent shapes on the ground.
Credit: Leonard David

Yes, I survived the Great American Eclipse of 2017, soaking up the solar eclipse in Casper, Wyoming.

For my new Space.com story, go to:

‘Mr. Eclipse’ Explains Why the 2017 Total Solar Eclipse Is Special

By Leonard David, Space.com’s Space Insider Columnist

August 22, 2017 07:30am ET

https://www.space.com/37898-total-eclipse-in-casper-wyoming-fred-espenak.html

Curiosity Mastcam Left image taken on Sol 1789. August 18, 2017.
Credit: NASA/JPL-Caltech/MSSS

NASA’s Curiosity Mars rover is performing Sol 1790 science duties – ready to carry out a list of tasks.

The robot did not cover a planned drive of 50 feet (15 meters), instead chalking up about 36 feet (11 meters).

But the rover moved far enough down the road to get in good position to acquire a full high-resolution mosaic of Vera Rubin Ridge (VRR) over the weekend, reports Mark Salvatore, a planetary geologist at the University of Michigan in Dearborn.

Curiosity Front Hazcam Right B image acquired on Sol 1790, August 19, 2017.
Credit: NASA/JPL-Caltech

Nice sandy location

“In addition, Curiosity parked herself in a nice sandy location where we can continue to investigate sand ripples on our way towards the ridge,” Salvatore adds. The science team has planned a full weekend of scientific investigations and data collection.

On the schedule, Curiosity’s Chemistry and Camera (ChemCam) will kick off this weekend’s science plan by investigating the chemistry of two of the few rocky targets in front of the rover: “Zephyr Ledges,” the multi-toned flaky patch of rocky material surrounded by sand ripples, and “Wallace Ledge,” which is a more massive piece of rock a bit further from the rover.

Curiosity Mastcam Left image taken on Sol 1788, August 17. 2017.
Credit: NASA/JPL-Caltech/MSSS

Two rocky targets

Following these chemistry measurements, the robot’s Mastcam will be used to document these two rocky targets, including a multispectral observation of “Zephyr Ledges” and the surrounding sands, Salvatore explains.

“Multispectral observations collect images at more wavelengths than our eyes are accustomed to viewing, which allows us to detect ‘color’ variations that help us to decipher the composition of these different materials,” Salvatore says.

ChemCam will also collect a high-resolution image mosaic of VRR from this location before Sol 1790’s first block of scientific investigations is completed. The second science block of Sol 1790 will be dedicated exclusively to collecting a twelve image mosaic of VRR using Mastcam.

Curiosity Mastcam Right image taken on Sol 1788, August 17, 2017.
Credit: NASA/JPL-Caltech/MSSS

Essential mosaics

Salvatore points out that these mosaics are essential to understand the structure of the ridge as can be seen from this perspective. “Once we are up on VRR itself, we will be unable to see these subsurface layers in the same context.”

Late in the afternoon on Sol 1790, Curiosity will unfurl its robotic arm and begin a chemistry analysis of a sand ripple named “The Shivers” using the Alpha Particle X-Ray Spectrometer (APXS) instrument.

“This measurement will last several hours, as the X-rays and alpha particles are generated by the slow radioactive decay of curium within the instrument. The longer the APXS is put in contact with a sample of interest, the more precise the chemical measurement will be,” Salvatore explains.

Ripple effects

Following the measurement of The Shivers, the robot’s APXS will then be moved to another sand ripple target known as “Trumpet,” where it will remain overnight to collect several additional hours of chemical analyses.

“As has been commonly seen in Gale crater, sand ripples exhibit differences in both color and grain size, even over very short distances,” reports Salvatore. “These variations provide really valuable information about wind patterns, the size of particles that can be moved by the wind, and whether there is any difference in composition between sediments of different grain sizes. Both “The Shivers” and “Trumpet” exhibit such differences in color and grain size, which is why they are targets of investigation for this weekend’s science plan.”

Curiosity Mars Descent Imager (MARDI) image acquired on Sol 1788, August 17, 2017.
Credit: NASA/JPL-Caltech/MSSS

Local environment

Salvatore explains that on Sol 1791, Curiosity will focus on monitoring the local environment in Gale crater. Standard measurements of the local weather and radiation environment will be made, as well as passive sky observations using ChemCam.

“Mastcam will be employed to image the distant rim of Gale crater, as a means of determining how dusty the martian atmosphere is on this day. These measurements are extremely valuable for several reasons, including understanding whether the martian atmosphere will hinder our ability to study the surface both from the ground and from orbit,” Salvatore adds.

Planned drive ahead

On Sol 1792, the scripted plan calls for Curiosity to head off on a planned drive of over 130 feet (40 meters) drive to the east-southeast along the planned VRR ascent route.

After the drive, Curiosity is slated to acquire Navcam and Mascam images of the rover’s immediate surroundings for the science team to use in their planning efforts on Monday morning. As always, the Mars Descent Imager (MARDI) will also acquire an image from below the rover.

Credit: NASA/JPL-Caltech/University of Arizona

Shallow sand bars

“Thinking back to the two rocky targets being investigated on the first day of this weekend plan, “Zephyr Ledges” and “Wallace Ledge,” I can’t help but think of how perfect these names are at this stage of the mission,” Salvatore recalls. “On Earth, these two names correspond to shallow sand bars off the east coast of Maine, in the shallow ocean near more prominent islands that rise above the water.”

Lastly, as Curiosity starts to make preparations to ascend Vera Rubin Ridge, “you can imagine the shallow sand sea that Curiosity is currently exploring and looking up towards the more prominent ridge just to the south,” Salvatore adds. “Take away the mighty Atlantic Ocean, and I wouldn’t be surprised if the hike from one of these shallow sand bars up to a nearby island doesn’t feel similar to Curiosity’s upcoming ascent from the lower Murray formation up into Vera Rubin Ridge,” he concludes.

New road map

Meanwhile, a new Curiosity traverse map through Sol 1789 has been issued.

The map shows the route driven by NASA’s Mars rover Curiosity through the 1789 Martian day, or sol, of the rover’s mission on Mars, as of August 18, 2017.

Numbering of the dots along the line indicate the sol number of each drive. North is up. The scale bar is 1 kilometer (~0.62 mile).

From Sol 1788 to Sol 1789, Curiosity had driven a straight line distance of about 61.76 feet (18.83 meters), bringing the rover’s total odometry for the mission since landing in August 2012 to 10.66 miles (17.16 kilometers).

The base image from the map is from the High Resolution Imaging Science Experiment Camera (HiRISE) onboard NASA’s Mars Reconnaissance Orbiter.

Curiosity Front Hazcam Left B image taken on Sol 1788, August 17, 2017.
Credit: NASA/JPL-Caltech

NASA’s Curiosity Mars rover is now busy at work during Sol 1789.

Christopher Edwards, a planetary geologist from Northern Arizona University in Flagstaff, Arizona reports: “After completing a successful drive back to the strategic route to continue up the Vera Rubin Ridge, we arrived at a workspace filled with sand and a lone rock outcrop dubbed “Dumplings Island.”

Curiosity Navcam Left B image taken on Sol 1788, August 17, 2017.
Image Credit: NASA/JPL-Caltech

This rock outcrop was the focus of most of planned activities, including high resolution microscopic imaging with the Mars Hand Lens Imager (MAHLI) to characterize the outcrop’s particle size and small scale textures.

 

Compositional data point

Edwards adds that MAHLI, Alpha Particle X-Ray Spectrometer (APXS) and Chemistry and Camera (ChemCam) observations are geared to understand the composition of the Dumplings Island outcrop, “providing another important compositional data point as Curiosity traverses the Vera Rubin Ridge stratigraphy.”

Curiosity Navcam Right B image taken on Sol 1788, August 17, 2017.
Credit: NASA/JPL-Caltech

The rover has passed its “Slip Risk Assessment Process (SRAP)” with flying colors, Edwards notes, which was needed to carry out Curiosity’s robotic arm-based activities in a current plan.

 

Wheel slippage

After finishing the drive to its current location, the Mars machinery ended up on a relatively flat spot with its wheels in good contact with the sandy surface that likely overlies bedrock.

“As such, the likelihood of rover wheel slippage due to arm activities was judged to be very low,” Edwards adds.

Curiosity Mastcam Right image taken on Sol 1787, August 16, 2017.
Credit: NASA/JPL-Caltech/MSSS

Wiggle room – not much

Given the strong desire to continue to drive up the Vera Rubin Ridge, there was a trade off between extending the duration of science activities and extending the planned drive, Edwards explains. “As the plan was already quite busy, no additional science duration was able to be allocated and the rover only got a few more minutes of drive time. In all, there wasn’t much wiggle room in today’s plan! Not much additional imaging, other than that required to characterize the compositional targets, made it in to the plan either,” he reports.

Curiosity Mars Hand Lens Imager (MAHLI) image from Sol 1788, August 17, 2017. MAHLI is located on the turret at the end of the rover’s robotic arm.
Credit: NASA/JPL-Caltech/MSSS

Strategic route

The path for the coming sols should follow a pre-defined strategic route closely, due to the fact that there’s a lower slope gap in the steep cliffs of the Vera Rubin Ridge.

That being the case, it makes for a safe path to the top.

 

Concludes Edwards: “It should be an exciting next few days of planning with some great views once Curiosity makes it to the top of the ridge and can look out over the path that’s been driven in the past 5 years of Mars surface operations.”

A recovered Saturn V booster element is showcased by Jeff Bezos who financed an ocean recovery of Apollo-era hardware.
Credit: The Museum of Flight, Seattle, Washington

Jeff Bezos, the billionaire mogul behind Amazon.com and the head of his Blue Origin rocket group, is passionate about space exploration as well as its historical roots.

Bezos recently told his story regarding dredging up Apollo remembrances – hardware resting three-miles deep in Atlantic Ocean waters.

For more information on Bezos and his salvaging of the past, go to my new Space.com story at:

Apollo’s Deep-Sea Fisherman: Jeff Bezos Recounts Saturn V Salvage Expedition

https://www.space.com/37830-jeff-bezos-apollo-rocket-engines-recovery.html