NASA Archives

August 11, 2014December 23, 2015 by Ken Kremer

Coma Dust Collection Science starts for Rosetta at Comet 67P/Churyumov-Gerasimenko

Rosetta NAVCAM image taken on 10 August 2014 from a distance of about 110 km from comet 67P/Churyumov-Gerasimenko. The comet nucleus is about 4 km across. Credit: ESA/Rosetta/NAVCAM

With the historic arrival of the European Space Agency’s (ESA) Rosetta spacecraft at destination Comet 67P/Churyumov-Gerasimenko flawlessly accomplished on August 6, 2014 after a decade long journey, ground breaking up close science at this bizarre world has begun while the team diligently and simultaneously searches for a landing site for the attached Philae comet lander.

Rosetta started collecting cometary dust from the coma encircling the comet’s nucleus with the onboard COSIMA instrument on Sunday, August 10, 2014 as the spacecraft orbits around and ahead of the icy wanderer from a distance of approximately 100 kilometers (62 miles). See coma image below.

Hopes are high that unprecedented science discoveries await at this alien world described as a “Scientific Disneyland,” by Mark McCaughrean, senior scientific adviser to ESA’s Science Directorate, during ESA’s live arrival day webcast. “It’s just astonishing.”

COSIMA stands for Cometary Secondary Ion Mass Analyser and is one of Rosetta’s suite of 11 state-of-the-art science instruments with a combined mass of 165 kg.

Its purpose is to conduct the first “in situ” analysis of the grains of dust particles emitted from the comets nucleus and determine their physical and chemical characteristics, including whether they are organic or inorganic – in essence what is cometary dust material made of and how it differs from the surface composition.

COSIMA will collect the coma dust using 24 specially designed ‘target holders’ – the first of which was opened to study the comets environment on Aug. 10. Since the comet is not especially active right now, the team plans to keep the target holder open for at least a month and check the progress of any particle collections on a weekly basis.

COSISCOPE image of the first target taken on 19 July 2014 (before the exposure, on 10 August, for cometary dust collection). The 1x1 cm target consists of a gold plate covered with a thin layer (30 µm) of gold nanoparticles (“gold black”). Illumination is by two LEDs, from the right side in this case. The bright dots on the vertical strip on the right side are used for target identification and for defining the coordinate system. Credits: ESA/Rosetta/MPS for COSIMA Team MPS/CSNSM/UNIBW/TUORLA/IWF/IAS/ESA/BUW/MPE/LPC2E/LCM/FMI/UTU/LISA/UOFC/vH&S — COSISCOPE image of the first target taken on 19 July 2014 (before the exposure, on 10 August, for cometary dust collection). The 1×1 cm target consists of a gold plate covered with a thin layer (30 µm) of gold nanoparticles (“gold black”). Illumination is by two LEDs, from the right side in this case. The bright dots on the vertical strip on the right side are used for target identification and for defining the coordinate system. Credits: ESA/Rosetta/MPS for COSIMA Team MPS/CSNSM/UNIBW/TUORLA/IWF/IAS/ESA/BUW/MPE/LPC2E/LCM/FMI/UTU/LISA/UOFC/vH&S

In fact the team says the coma environment “is still comparable to a high-quality cleanroom”at this time.

But everyone expects that to change radically as Rosetta continues escorting Comet 67P as it loops around the sun, getting closer and warming the surface every day and until reaching perihelion in August 2015.

COSIMA is managed by the Max Planck Institute for Solar System Research (Max-Planck-Institut für Sonnensystemforschung ) in Katlenburg-Lindau, Germany, with Principal Investigator Martin Hilchenbach.

There are also substantial contributions from the Institut d’Astrophysique Spatiale in France, Finnish Meteorological Institute, Osterreichisches Forschungszentrum Seibersdorf and more.

The target holders measure about one square centimeter and were developed by the Universität der Bundeswehr in Germany.

Each of these targets measures one square centimeter and is comprised of a gold plate covered with a thin 30 µm layer of gold nanoparticles (“gold black”) which the team says should “decelerate and capture cometary dust particles impacting with velocities of ~100 m/s.”

The target will be illuminated by a pair of LED’s to find the dust particles. The particles will be analyzed by COSIMA’s built in mass spectrometer after being located on the target holder by the French supplied COSISCOPE microscopic camera and ionized by a beam of indium ions.

Photo of the COSIMA (Cometary Secondary Ion Mass Analyser) instrument on Rosetta. Credit: Max Planck Institute for Solar System Research/ESA

The team expects any grains found on the first target to be analyzed by mid-September 2014.

“COSIMA uses the method of Secondary Ion Mass Spectrometry. They will be fired at with a beam of Indium ions. This will spark individual ions (we say secondary ions) from their surfaces, which will then be analysed with COSIMA’s mass spectrometer,” according to a description from the COSIMA team.

The mass spec has the capability to analyze the elemental composition in an atomic mass range of 1 to 4000 atomic mass units, determine isotopic abundances of some key elements, characterize organic components and functional groups, and conduct mineralic and petrographic characterization of the inorganic phases, all of which will inform as as never before about solar system chemistry.

Comets are leftover remnants from the formation of the solar system. Scientists believe they delivered a vast quantity of water to Earth. They may have also seeded Earth with organic molecules – the building blocks of life as we know it.

Any finding of organic molecules and their identification by COSIMA will be a major discovery for Rosetta and ESA and inform us about the origin of life on Earth.

Data obtained so far from Rosetta’s VIRTIS instrument indicates the comets surface is too hot to be covered in ice and must instead have a dark, dusty crust.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

…….

Read my Rosetta series here:

What’s Ahead for Rosetta – ‘Finding a Landing Strip’ on Bizarre Comet 67P/Churyumov-Gerasimenko

Rosetta Arrives at ‘Scientific Disneyland’ for Ambitious Study of Comet 67P/Churyumov-Gerasimenko after 10 Year Voyage

Rosetta on Final Approach to Historic Comet Rendezvous – Watch Live Here

Rosetta Probe Swoops Closer to Comet Destination than ISS is to Earth and Reveals Exquisite Views

Rosetta Orbiter less than 500 Kilometers from Comet 67P Following Penultimate Trajectory Burn

Rosetta Closing in on Comet 67P/Churyumov-Gerasimenko after Decade Long Chase

ESA’s Rosetta Spacecraft nears final approach to Comet 67P/Churyumov-Gerasimenko in late July 2014. This collage of imagery from Rosetta combines Navcam camera images at right taken nearing final approach from July 25 (3000 km distant) to July 31, 2014 (1327 km distant), with OSIRIS wide angle camera image at left of comet’s expanding coma cloud on July 25. Images to scale and contrast enhanced to show further detail. Credit: ESA/Rosetta/NAVCAM/OSIRIS/MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA Collage/Processing: Marco Di Lorenzo/Ken Kremer

August 9, 2014December 23, 2015 by Ken Kremer

Airframe Structure for First Commercial Dream Chaser Spacecraft Unveiled

SNC's Dream Chaser® orbital structural airframe at Lockheed Martin in Ft. Worth, Texas. Credit: Lockheed Martin

The orbital airframe structure for the first commercial Dream Chaser mini-shuttle that will launch to Earth orbit just over two years from now has been unveiled by Sierra Nevada Corporation (SNC) and program partner Lockheed Martin.

Sierra Nevada is moving forward with plans for Dream Chaser’s first launch and unmanned orbital test flight in November 2016 atop a United Launch Alliance (ULA) Atlas V rocket from Cape Canaveral, Florida.

The winged Dream Chaser is being developed under NASA’s Commercial Crew Program aimed at restoring America’s indigenous human spaceflight access to low Earth orbit and the International Space Station (ISS).

Dream Chaser commercial crew vehicle built by Sierra Nevada Corp docks at ISS

Lockheed Martin is fabricating the structural components for the Dream Chaser’s orbital spacecraft composite structure at the NASA’s Michoud Assembly Facility (MAF) in New Orleans, Louisiana.

MAF has played a long and illustrious history in human space flight dating back to Apollo and also as the site where all the External Tanks for NASA’s space shuttle program were manufactured. Lockheed Martin also builds the pressure vessels for NASA’s deep space Orion crew vehicle at MAF.

Each piece is thoroughly inspected to insure it meets specification and then shipped to Lockheed Martin’s Aeronautics facility in Fort Worth, Texas for integration into the airframe and co-bonded assembly.

Following helicopter release the private Dream Chaser spaceplane starts glide to runway at Edwards Air Force Base, Ca. during first free flight landing test on Oct. 26, 2013 - in this screenshot. Credit: Sierra Nevada Corp. — Following helicopter release the private Dream Chaser spaceplane starts glide to runway at Edwards Air Force Base, Ca. during first free flight landing test on Oct. 26, 2013 – in this screenshot. Credit: Sierra Nevada Corp.

Sierra Nevada chose Lockheed Martin for this significant role in building Dream Chaser airframe based on their wealth of aerospace experience and expertise.

The composite airframe structure was recently unveiled at a joint press conference by Sierra Nevada Corporation and Lockheed Martin at the Fort Worth facility.

“As a valued strategic partner on SNC’s Dream Chaser Dream Team, Lockheed Martin is under contract to manufacture Dream Chaser orbital structure airframes,” said Mark N. Sirangelo, corporate vice president of SNC’s Space Systems, in a statement.

“We competitively chose Lockheed Martin because they are a world leader in composite manufacturing, have the infrastructure, resources and quality control needed to support the needs of an orbital vehicle and have a proven track record of leading our nation’s top aviation and aerospace programs. Lockheed Martin’s diverse heritage coupled with their current work on the Orion program adds an extra element of depth and expertise to our program. SNC and Lockheed Martin continue to expand and develop a strong multi-faceted relationship.”

Dream Chaser measures about 29 feet long with a 23 foot wide wing span and is about one third the size of NASA’s space shuttle orbiters.

“We are able to tailor our best manufacturing processes, and our innovative technology from across the corporation to fit the needs of the Dream Chaser program,” said Jim Crocker, vice president of Lockheed Martin’s Space Systems Company Civil Space Line of Business.

Upon completion of the airframe manufacturing at Ft Worth, it will be transported to SNC’s Louisville, Colorado, facility for final integration and assembly.

Lockheed Martin will also process Dream Chaser between orbital flights at the Kennedy Space Center, FL in the recently renamed Neil Armstrong Operations and Checkout Building.

SNC announced in July that they successfully completed and passed a series of risk reduction milestone tests on key flight hardware systems under its Commercial Crew Integrated Capability (CCiCap) agreement with NASA that move the private reusable spacecraft closer to its critical design review (CDR) and first flight.

As a result of completing Milestones 9 and 9a, SNC has now received 92% of its total CCiCAP Phase 1 NASA award of $227.5 million.

“We are on schedule to launch our first orbital flight in November of 2016, which will mark the beginning of the restoration of U.S. crew capability to low-Earth orbit,” says Sirangelo.

The private Dream Chaser is a reusable lifting-body design spaceship that will carry a mix of cargo and up to a seven crewmembers to the ISS. It will also be able to land on commercial runways anywhere in the world, according to SNC.

Dream Chaser is among a trio of US private sector manned spaceships being developed with seed money from NASA’s Commercial Crew Program in a public/private partnership to develop a next-generation crew transportation vehicle to ferry astronauts to and from the International Space Station by 2017 – a capability totally lost following the space shuttle’s forced retirement in 2011.

The SpaceX Dragon and Boeing CST-100 ‘space taxis’ are also vying for funding in the next round of contracts to be awarded by NASA around September 2014, NASA officials have told me.

Stay tuned here for Ken’s continuing Sierra Nevada, Boeing, SpaceX, Orbital Sciences, commercial space, Orion, Rosetta, Curiosity, Mars rover, MAVEN, MOM and more planetary and human spaceflight news.

Ken Kremer

Scale models of NASA’s Commercial Crew program vehicles and launchers; Boeing CST-100, Sierra Nevada Dream Chaser, SpaceX Dragon. Credit: Ken Kremer/kenkremer.com

August 8, 2014December 23, 2015 by Ken Kremer

Curiosity Celebrates Two Years on Mars Approaching Bedrock of Mountain Climbing Destination

1 Martian Year on Mars! Curiosity treks to Mount Sharp in this photo mosaic view captured on Sol 669, June 24, 2014. Navcam camera raw images stitched and colorized. Credit: NASA/JPL-Caltech/Marco Di Lorenzo/Ken Kremer – kenkremer.com

2 Years on Mars!
Curiosity treks to Mount Sharp, her primary science destination, in this photo mosaic view captured on Sol 669, June 24, 2014. Navcam camera raw images stitched and colorized. Credit: NASA/JPL-Caltech/Marco Di Lorenzo/Ken Kremer – kenkremer.com
Story and mosaics updated[/caption]

NASA’s most scientifically powerful rover ever dispatched to the Red Planet, Curiosity, is celebrating her 2nd anniversary on Mars since the dramatic touchdown inside Gale Crater on Aug. 6, 2012, EDT (Aug. 5, 2012, PDT) while simultaneously approaching a bedrock unit that for the first time is actually part of the humongous mountain she will soon scale and is the primary science destination of the mission.

Mount Sharp is a layered mountain that dominates most of Gale Crater and towers 3.4 miles (5.5 kilometers) into the Martian sky and is taller than Mount Rainier.

Aug. 6, 2014 marks ‘2 Years on Mars’ and Sol 711 for Curiosity in an area called “Hidden Valley.”

“Getting to Mount Sharp is the next big step for Curiosity and we expect that in the Fall of this year,” Dr. Jim Green, NASA’s Director of Planetary Sciences at NASA Headquarters, Washington, DC, told me in an interview making the 2nd anniversary.

The 1 ton rover is equipped with 10 state-of-the-art science instruments and searching for signs of life.

The mysterious mountain is so huge that outcrops of bedrock extend several miles out from its base and Curiosity is now within striking distance of reaching the area the rover team calls “Pahrump Hills.”

2 Earth Years on Mars! NASA’s Curiosity rover celebrated the 2nd anniversary on Mars at ‘Hidden Valley’ as shown in this photo mosaic view captured on Aug. 6, 2014, Sol 711. Note the valley walls, rover tracks and distant crater rim. Navcam camera raw images stitched and colorized. Credit: NASA/JPL-Caltech/Ken Kremer-kenkremer.com/Marco Di Lorenzo — 2 Earth Years on Mars!
NASA’s Curiosity rover celebrated the 2nd anniversary on Mars at ‘Hidden Valley’ as shown in this photo mosaic view captured on Aug. 6, 2014, Sol 711. Note the valley walls, rover tracks and distant crater rim. Navcam camera raw images stitched and colorized. Credit: NASA/JPL-Caltech/Ken Kremer-kenkremer.com/Marco Di Lorenzo

Scientists anticipate that the outcrops at “Pahrump Hills” offer a preview of a geological unit that is part of the base of Mount Sharp for the first time since landing rather than still belonging to the floor of Gale Crater.

“We’re coming to our first taste of a geological unit that’s part of the base of the mountain rather than the floor of the crater,” said Curiosity Project Scientist John Grotzinger of the California Institute of Technology, Pasadena, in a statement.

“We will cross a major terrain boundary.”

Since “Pahrump Hills” is less than one-third of a mile (500 meters) from Curiosity she should arrive soon.

In late July 2014, the rover arrived in an area of sandy terrain called “Hidden Valley” which is on the planned route ahead leading to “Pahrump Hills” and easily traversable with few of the sharp edged rocks that have caused significant damage to the rovers six aluminum wheels.

This full-circle panorama of the landscape surrounding NASA's Curiosity Mars rover on July 31, 2014, Sol 705, offers a view into sandy lower terrain called "Hidden Valley," which is on the planned route ahead. It combines several images from Curiosity's Navigation Camera. South is at the center. Credit: NASA/JPL-Caltech — This full-circle panorama of the landscape surrounding NASA’s Curiosity Mars rover on July 31, 2014, Sol 705, offers a view into sandy lower terrain called “Hidden Valley,” which is on the planned route ahead. It combines several images from Curiosity’s Navigation Camera. South is at the center. Credit: NASA/JPL-Caltech

The sedimentary layers in the lower slopes of Mount Sharp have been Curiosity’s long-term science destination.

They are the principal reason why the science team specifically chose Gale Crater as the primary landing site based on high resolution spectral observations collected by NASA’s powerful Mars Reconnaissance Orbiter (MRO) indicating the presence of deposits of clay-bearing sedimentary rocks.

Curiosity’s goal all along has been to determine whether Mars ever offered environmental conditions favorable for microbial life. Finding clay bearing minerals. or phyllosilicates, in Martian rocks is the key to fulfilling its major objective.

The team expected to find the clay bearing minerals only in the sedimentary layers at the lower reaches of Mount Sharp.

Curiosity rover panorama of Mount Sharp captured on June 6, 2014 (Sol 651) during traverse inside Gale Crater. Note rover wheel tracks at left. She will eventually ascend the mountain at the ‘Murray Buttes’ at right later this year. Assembled from Mastcam color camera raw images and stitched by Marco Di Lorenzo and Ken Kremer. Credit: NASA/JPL/MSSS/Marco Di Lorenzo/Ken Kremer-kenkremer.com

Soon after landing, the team spotted some rather interesting looking outcrops barely a half mile away from the touchdown zone at a spot dubbed ‘Yellowknife Bay” and decided to take a detour towards it to investigate.

Well the scientists won the bet and struck scientific gold barely six months after landing when they drilled into a rock outcrop named “John Klein” at “Yellowknife Bay” and unexpectedly discovered the clay bearing minerals on the crater floor.

Yellowknife Bay was found to be an ancient lakebed where liquid water flowed on Mars surface billions of years ago.

The discovery of phyllosilicates in the 1st drill sample during the spring of 2013 meant that Curiosity had rather remarkably already fulfilled its primary goal of finding a habitable zone during its first year of operations!

The rock analysis “yielded evidence of a lakebed environment billions of years ago that offered fresh water, all of the key elemental ingredients for life, and a chemical source of energy for microbes, if any existed there,” according to NASA.

Curiosity accomplished Historic 1st drilling into Martian rock at John Klein outcrop on Feb 8, 2013 (Sol 182) and discovered a habitable zone, shown in this context mosaic view of the Yellowknife Bay basin taken on Jan. 26 (Sol 169). The robotic arm is pressing down on the surface at John Klein outcrop of veined hydrated minerals – dramatically back dropped with her ultimate destination; Mount Sharp. Credit: NASA/JPL-Caltech/Ken Kremer-kenkremer.com/Marco Di Lorenzo

“Before landing, we expected that we would need to drive much farther before answering that habitability question,” said Curiosity Project Scientist John Grotzinger of the California Institute of Technology, Pasadena. “We were able to take advantage of landing very close to an ancient streambed and lake. Now we want to learn more about how environmental conditions on Mars evolved, and we know where to go to do that.”

During the rovers second Earth year on the Red Planet, Curiosity has been driving as fast as possible towards a safe entry point to the slopes of Mount Sharp. The desired destination for the car sized rover is now about 2 miles (3 kilometers) southwest of its current location.

‘Driving, Driving, Driving’ is indeed the rover teams mantra.

The main map here shows the assortment of landforms near the location of NASA's Curiosity Mars rover as the rover's second anniversary of landing on Mars nears. The gold traverse line entering from upper right ends at Curiosity's position as of Sol 705 on Mars (July 31, 2014). The inset map shows the mission's entire traverse from the landing on Aug. 5, 2012, PDT (Aug. 6, EDT) to Sol 705, and the remaining distance to long-term science destinations near Murray Buttes, at the base of Mount Sharp. The label "Aug. 5, 2013" indicates where Curiosity was one year after landing. Credit: NASA/JPL-Caltech/Univ. of Arizona — The main map here shows the assortment of landforms near the location of NASA’s Curiosity Mars rover as the rover’s second anniversary of landing on Mars nears. The gold traverse line entering from upper right ends at Curiosity’s position as of Sol 705 on Mars (July 31, 2014). The inset map shows the mission’s entire traverse from the landing on Aug. 5, 2012, PDT (Aug. 6, EDT) to Sol 705, and the remaining distance to long-term science destinations near Murray Buttes, at the base of Mount Sharp. The label “Aug. 5, 2013” indicates where Curiosity was one year after landing. Credit: NASA/JPL-Caltech/Univ. of Arizona

To date, Curiosity’s odometer totals over 5.5 miles (9.0 kilometers) since landing inside Gale Crater on Mars in August 2012. She has taken over 174,000 images.

Curiosity still has about another 2 miles (3 kilometers) to go to reach the entry way at a gap in the treacherous sand dunes at the foothills of Mount Sharp sometime later this year.

And NASA is moving forward with future Red Planet missions when it recently announced the selection of 7 instruments chosen to fly aboard the Mars 2020 rover, the agency’s next rover going to Mars that will search for signs of ancient life as well as carry a technology demonstration that will help pave the way for ‘Humans to Mars’ in the 2030s. Read my story – here.

Coincidentally, ESA’s Rosetta comet hunting spacecraft arrived in orbit at its destination Comet 67P after a 10 year voyage on the same day as Curiosity’s 2 Earth year anniversary.

Stay tuned here for Ken’s continuing Rosetta, Curiosity, Opportunity, Orion, SpaceX, Boeing, Orbital Sciences, commercial space, MAVEN, MOM, Mars and more planetary and human spaceflight news.

Ken Kremer

Up close view of hole in one of rover Curiosity’s six wheels caused by recent driving over rough Martian rocks. Mosaic assembled from Mastcam raw images taken on Dec. 22, 2013 (Sol 490). Credit: NASA/JPL/MSSS/Ken Kremer - kenkremer.com/Marco Di Lorenzo — Up close view of hole in one of rover Curiosity’s six wheels caused by recent driving over rough Martian rocks. Mosaic assembled from Mastcam raw images taken on Dec. 22, 2013 (Sol 490). Credit: NASA/JPL/MSSS/Ken Kremer – kenkremer.com/Marco Di Lorenzo

August 7, 2014December 23, 2015 by Ken Kremer

What’s Ahead for Rosetta – ‘Finding a Landing Strip’ on Bizarre Comet 67P/Churyumov-Gerasimenko

NAVCAM image taken by Rosetta on 5 August 2014 from a distance of about 145 km from comet 67P/Churyumov-Gerasimenko. Image has been rotated 180 degrees. Credit: ESA/Rosetta/NAVCAM

Where would you land here?
Newly released NAVCAM image taken by Rosetta on 5 August 2014 from a distance of about 145 km from comet 67P/Churyumov-Gerasimenko. Image has been rotated 180 degrees. Credit: ESA/Rosetta/NAVCAM[/caption]

Following the flawless and history making arrival of the European Space Agency’s (ESA) Rosetta spacecraft at its long sought destination of Comet 67P/Churyumov-Gerasimenko on Wednesday, Aug. 6, the goal of conducting ground breaking science at this utterly alien and bizarre icy wanderer that looks like a ‘Scientific Disneyland’ can actually begin.

Rosetta is the first spacecraft in history to rendezvous with a comet and enter orbit – after a more than 10 year chase of 6.4 billion kilometers (4 Billion miles) along a highly complex trajectory from Earth. The arrival event was broadcast live from mission control at ESA’s spacecraft operations centre (ESOC) in Darmstadt, Germany. Read my complete arrival story – here.

So what’s ahead for Rosetta? Another audacious and history making event – Landing on the comet!

A top priority task is also another highly complex task – ‘Finding a landing strip’ on the bizarre world of Comet 67P for the piggybacked Philae comet lander equipped with 10 science instruments.

“The challenge ahead is to map the surface and find a landing strip,” said Andrea Accomazzo, ESA Rosetta Spacecraft Operations Manager, at the Aug. 6 ESA webcast.

That will be no easy task based on the spectacular imagery captured by the OSIRIS high resolution science camera and the Navcam camera that has revealed an utterly wacky and incredibly differentiated world like none other we have ever visited or expected when the mission was conceived.

Magnificently detailed new navcam images were released by ESA today, Aug, 7, streaming back to Earth across some 405 million kilometers (250 million miles) of interplanetary space – see above and below.

The team will have its hand full trying to find a safe spot for touchdown.

“We now see lots of structure and details. Lots of topography is visible on the surface,” said Holger Sierks, principal investigator for Rosetta’s OSIRIS camera from the Max Planck Institute for Solar System Research in Gottingen, Germany, during the webcast.

“There is a big depression and 150 meter high cliffs, rubble piles, and also we see smooth areas and plains. It’s really fantastic”

“We see a village of house size boulders. Some about 10 meters in size and bigger and they vary in brightness. And some with sharp edges. We don’t know their composition yet,” explained Sierks.

Newly released NAVCAM image taken on 6 August 2014 from a distance of about 96 km from comet 67P/Churyumov-Gerasimenko. Credit: ESA/Rosetta/NAVCAM

The key to finding a safe landing site for Philae will be quickly conducting a global comet mapping campaign with OSIRIS, Navcam and the remaining suite of 11 science instruments to provide a detailed scientific study of the physical characteristics and chemical composition of the surface.

They also need to determine which areas are hard or soft.

Holger Sierks, OSIRIS principal investigator, discuss spectacular hi res comet images returned so far by Rosetta during the Aug. 6 ESA webcast from mission control at ESOC, Darmstadt, Germany. Credit: Roland Keller — Holger Sierks, OSIRIS principal investigator, discusses spectacular hi res comet images returned so far by Rosetta during the Aug. 6 ESA webcast from mission control at ESOC, Darmstadt, Germany. Credit: Roland Keller

“Our first clear views of the comet have given us plenty to think about,” says Matt Taylor, ESA’s Rosetta project scientist.

“Is this double-lobed structure built from two separate comets that came together in the Solar System’s history, or is it one comet that has eroded dramatically and asymmetrically over time? Rosetta, by design, is in the best place to study one of these unique objects.”

Yesterday’s (Aug. 6) critical final thruster firing placed the 1.3 Billion euro robotic emissary from Earth into a triangular shaped orbit about 100 kilometers (62 miles) above and in front of the comet’s incredibly varied surface.

Therefore the initial mapping will be conducted from the 100 km (62 mi.) standoff distance.

Since the landing is currently targeted for November 11, 2014, in barely three months time there is not a moment to waste.

“Over the next few months, in addition to characterizing the comet nucleus and setting the bar for the rest of the mission, we will begin final preparations for another space history first: landing on a comet,” says Taylor.

The team will identify up to five possible landing sites by late August and expect to choose the primary site by mid-September.

Then the team has to plan and build the programming and maneuvers for the final timeline to implement the sequence of events leading to the nailbiting landing.

With Rosetta now travelling in a series of 100 kilometer-long (62 mile-long) triangular arcs in front of the comet lasting about 3 days each, it will also be firing thrusters at each apex.

After catching up with the comet Rosetta will slightly overtake and enter orbit from the ‘front’ of the comet as both the spacecraft and 67P/CG move along their orbits around the Sun. Rosetta will carry out a complex series of manoeuvres to reduce the separation between the spacecraft and comet from around 100 km to 25-30 km. From this close orbit, detailed mapping will allow scientists to determine the landing site for the mission’s Philae lander. Immediately prior to the deployment of Philae in November, Rosetta will come to within just 2.5 km of the comet’s nucleus. This animation is not to scale; Rosetta’s solar arrays span 32 m, and the comet is approximately 4 km wide. Credit: ESA–C. Carreau

But it will also gradually edge closer over the next six weeks to about 50 km distance and then even closer to lower Rosetta’s altitude about Comet 67P until the spacecraft is captured by the comet’s gravity.

In November 2014, Rosetta will attempt another historic first when it deploys the Philae science lander from an altitude of just about 2.5 kilometers above the comet for the first ever attempt to land on a comet’s nucleus.

The three-legged lander will fire harpoons and use ice screws to anchor itself to the 4 kilometer (2.5 mile) wide comet’s surface. Philae will collect stereo and panoramic images and also drill into and sample its incredibly varied surface.

How will Philae land?

Stefan Ulamec, Philae Lander Manager from the German Aerospace Center (DLR) talked about the challenges of landing in a low gravity environment during the ESA webcast.

“The touchdown will be at a speed of just 1 m/s,” Ulamec explained. “This is like walking and bouncing against a wall.”

Details in an upcoming story!

Why study comets?

Comets are leftover remnants from the formation of the solar system. Scientists believe they delivered a vast quantity of water to Earth. They may have also seeded Earth with organic molecules.

Stay tuned here for Ken’s continuing Rosetta, Curiosity, Opportunity, Orion, SpaceX, Boeing, Orbital Sciences, commercial space, MAVEN, MOM, Mars and more Earth and Planetary science and human spaceflight news.

Ken Kremer

…….

Read my Rosetta series here:

Rosetta Arrives at ‘Scientific Disneyland’ for Ambitious Study of Comet 67P/Churyumov-Gerasimenko after 10 Year Voyage

Rosetta on Final Approach to Historic Comet Rendezvous – Watch Live Here

Rosetta Probe Swoops Closer to Comet Destination than ISS is to Earth and Reveals Exquisite Views

Rosetta Orbiter less than 500 Kilometers from Comet 67P Following Penultimate Trajectory Burn

Rosetta Closing in on Comet 67P/Churyumov-Gerasimenko after Decade Long Chase

August 6, 2014December 23, 2015 by Ken Kremer

Rosetta Arrives at ‘Scientific Disneyland’ for Ambitious Study of Comet 67P/Churyumov-Gerasimenko after 10 Year Voyage

The image of Comet 67P/Churyumov-Gerasimenko was taken by Rosetta’s OSIRIS narrow-angle camera on 3 August 2014 from a distance of 285 km. Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
Story updated[/caption]

“We’re at the comet! Yes,” exclaimed Rosetta Spacecraft Operations Manager Sylvain Lodiot, confirming the spacecraft’s historic arrival at Comet 67P/Churyumov-Gerasimenko during a live webcast this morning, Aug. 6, from mission control at ESA’s spacecraft operations centre (ESOC) in Darmstadt, Germany.

The European Space Agency’s (ESA) Rosetta comet hunter successfully reached its long sought destination after a flawless orbital thruster firing at 11 AM CEST to become the first spacecraft in history to rendezvous with a comet and enter orbit aimed at an ambitious long term quest to produce ground breaking science.

“Ten years we’ve been in the car waiting to get to scientific Disneyland and we haven’t even gotten out of the car yet and look at what’s outside the window,” Mark McCaughrean, senior scientific adviser to ESA’s Science Directorate, said during today’s webcast. “It’s just astonishing.”

“The really big question is where did we and the solar system we live in come from? How did water and the complex organic molecules that build up life get to this planet? Water and life. These are the questions that motivate everybody.”

“Rosetta is indeed the ‘rosetta stone’ that will unlock this treasure chest to all comets.”

Today’s rendezvous climaxed Rosetta’s decade long and 6.4 billion kilometers (4 Billion miles) hot pursuit through interplanetary space for a cosmic kiss with Comet 67P while speeding towards the inner Solar System at nearly 55,000 kilometers per hour.

The probe is sending back spectacular up close high resolution imagery of the mysterious binary, two lobed comet, merged at a bright band at the narrow neck of the celestial wanderer that looks like a ‘rubber ducky.’

“This is the best comet nucleus ever resolved in space with the sharpest ever views of the nucleus, with 5.5.meter pixel resolution,” said Holger Sierks, principal investigator for Rosetta’s OSIRIS camera from the Max Planck Institute for Solar System Research in Gottingen, Germany, during the webcast.

Back side view of Comet 67P/Churyumov-Gerasimenko was taken by Rosetta’s OSIRIS narrow-angle camera on 3 August 2014 from a distance of 285 km. The image resolution is 5.3 metres/pixel. Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

“We now see lots of structure and details. Lots of topography is visible on the surface. We see the nucleus and outgassing activity. The outbursts are seen with overexposed images. It’s really fantastic”

“There is a big depression on the head and 150 meter high cliffs, rubble piles, and also we see smooth areas and plains. The neck is about 1000 meters deep and is a cool area. There is outgassing visible from the neck.”

“We see a village of house size boulders. Some about 10 meters in size and bigger they vary in brightness. And some with sharp edges. We don’t know their composition yet.”

“We don’t understand how its created yet. That’s what we’ll find out in coming months as we get closer.”

“Rosetta has arrived and will get even closer. We’ll get ten times the resolution compared to now.”

“The comet is a story about us. It will be the key in cometary science. Where did it form? What does it tell us about the water on Earth and the early solar system and where it come from?”

Following the blastoff on 2 March 2004 tucked inside the payload fairing of an Ariane 5 G+ rocket from Europe’s spaceport in Kourou, French Guiana, Rosetta traveled on a complex trajectory.

It conducted four gravity assist speed boosting slingshot maneuvers, three at Earth and one at Mars, to gain sufficient velocity to reach the comet, Lodiot explained.

The 1.3 Billion euro robotic emissary from Earth is now orbiting about 100 kilometers (62 miles) above the comet’s surface, some 405 million kilometers (250 million mi.) from Earth, about half way between the orbits of Jupiter and Mars.

The main event today, Aug. 6, was to complete an absolutely critical thruster firing which was the last of 10 orbit correction maneuvers (OCM’s). It started precisely on time at 11:00 AM CEST/09:00 GMT/5:00 AM EST, said Lodiot. The signal was one of the cleanest of the entire mission.

The orbital insertion engine firing dubbed the Close Approach Trajectory – Insertion (CATI) burn was scheduled to last about 6 minutes 26 seconds. Confirmation of a successful burn came some 28 minutes later.

“We’re at the comet! Yes,” Lodiot excitedly announced live whereupon the crowd of team members, dignitaries and journalists at ESOC erupted in cheers.

For the next 17 months, the probe will escort comet 67P as it loops around the Sun towards perihelion in August 2015 and then continue along on the outbound voyage towards Jupiter.

ESA’s incredibly bold mission will also deploy the three-legged piggybacked Philae lander to touch down and drill into and sample its incredibly varied surface a little over three months from now.

Together, Rosetta and Philae are equipped with a suite of 21 science instruments to conduct an unprecedented investigation to characterize the 4 km wide (2.5 mi.) comet and study how the pristine frozen body composed of ice and rock is transformed by the warmth of the Sun.

Comets are believed to have delivered a vast quantity of water to Earth. They may have also seeded Earth with organic molecules.

Close-up detail of comet 67P/Churyumov-Gerasimenko. The image was taken by Rosetta’s OSIRIS narrow-angle camera and downloaded today, 6 August. The image shows the comet’s ‘head’ at the left of the frame, which is casting shadow onto the ‘neck’ and ‘body’ to the right. The image was taken from a distance of 120 km and the image resolution is 2.2 metres per pixel. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA — Close-up detail of comet 67P/Churyumov-Gerasimenko. The image was taken by Rosetta’s OSIRIS narrow-angle camera and downloaded today, 6 August. The image shows the comet’s ‘head’ at the left of the frame, which is casting shadow onto the ‘neck’ and ‘body’ to the right.
The image was taken from a distance of 120 km and the image resolution is 2.2 metres per pixel. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Rosetta and Philae will also search for organic molecules, nucleic acids and amino acids, the building blocks for life as we know it by sampling and analyzing the comets nucleus and coma cloud of gas and dust.

“The first coma sampling could happen as early as next week,” said Matt Taylor, ESA’s Rosetta project scientist on the webcast.

After thoroughly mapping the comet, the team will command Rosetta to move even lower to 50 km altitude and then even lower to 30 km and less.

The scientists and engineers will search for up to five possible landing sites for Philae to prepare for the touchdown in mid-November 2014.

“We want to characterize the nucleus so we can land in November,” said Taylor. “We will have a ringside along with the comet as it moves inwards to the sun and then further out.”

Comet 67P/Churyumov-Gerasimenko activity on 2 August 2014. The IMAGE was taken by Rosetta’s OSIRIS wide-angle camera from a distance of 550 km. The exposure time of the image was 330 seconds and the comet nucleus is saturated to bring out the detail of the comet activity. Note there is a ghost image to the right. The image resolution is 55 metres per pixel. Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Studying comets will shed light on the history of water and life on Earth.

“We are going to places we have never been to before,” said Jean-Jacques Dordain, ESA’s Director General during the webcast.

“We want to get answers to questions to the origin to water and complex molecules on Earth. This opens up even more new questions than answers.”

Watch for updates.

Ken Kremer

……..

Read my Rosetta series here:

Rosetta on Final Approach to Historic Comet Rendezvous – Watch Live Here

Rosetta Probe Swoops Closer to Comet Destination than ISS is to Earth and Reveals Exquisite Views

Rosetta Orbiter less than 500 Kilometers from Comet 67P Following Penultimate Trajectory Burn

Rosetta Closing in on Comet 67P/Churyumov-Gerasimenko after Decade Long Chase

August 5, 2014December 23, 2015 by Ken Kremer

Rosetta on Final Approach to Historic Comet Rendezvous – Watch Live Here

ESA’s Rosetta spacecraft on final approach to Comet 67P/Churyumov-Gerasimenko in early August 2014. This collage of navcam imagery from Rosetta was taken on Aug. 1, 2, 3 and 4 from distances of 1026 km, 500 km, 300 km and 234 km. Not to scale. Credit: ESA/Rosetta/NAVCAM – Collage/Processing: Marco Di Lorenzo/Ken Kremer- kenkremer.com
Watch ESA’s Live Webcast here on Aug. 6 starting at 4 AM EDT/ 8 AM GMT[/caption]

After a decade long chase of 6.4 billion kilometers (4 Billion miles) through interplanetary space the European Space Agency’s (ESA) Rosetta spacecraft is now on final approach for its historic rendezvous with its target comet 67P scheduled for Wednesday morning, Aug. 6. some half a billion kilometers from the Sun. See online webcast below.

Rosetta arrives at Comet 67P/Churyumov-Gerasimenko in less than 12 hours and is currently less than 200 kilometers away.

You can watch a live streaming webcast of Rosetta’s Aug. 6 orbital arrival here, starting at 10:00 a.m. CEST/8 a.m. GMT/4 a.m. EDT/1 a.m. PDT via a transmission from ESA’s spacecraft operations centre in Darmstadt, Germany.

Rosetta is the first mission in history to rendezvous with a comet and enter orbit around it. The probe will then escort comet 67P as it loops around the Sun, as well as deploy the piggybacked Philae lander to its uneven surface.

eurospaceagency on livestream.com. Broadcast Live Free

Orbit entry takes place after the probe initiates the last of 10 orbit correction maneuvers (OCM’s) on Aug. 6 starting at 11:00 CEST/09:00 GMT.

The thruster firing, dubbed the Close Approach Trajectory – Insertion (CATI) burn, is scheduled to last about 6 minutes 26 seconds. Engineers transmitted the commands last night, Aug. 4.

CATI will place the 1.3 Billion Euro Rosetta into an initial orbit at a distance of about 100 kilometers (62 miles).

Since the one way signal time is 22 min 29 sec, it will take that long before engineers can confirm the success of the CATI thruster firing.

As engineers at ESOC mission control carefully navigate Rosetta ever closer, the probe has been capturing spectacular imagery showing rocks, gravel and tiny crater like features on its craggily surface with alternating smooth and rough terrain and deposits of water ice.

See above and below our collages (created by Marco Di Lorenzo & Ken Kremer) of navcam camera approach images of the comet’s two lobed nucleus captured over the past week and a half. Another shows an OSIRIS camera image of the expanding coma cloud of water and dust.

The up close imagery revealed that the mysterious comet looks like a ‘rubber ducky’ and is comprised of two lobes merged at a bright band at the narrow neck in between.

Rosetta’s navcam camera has been commanded to capture daily images of the comet that rotates around once every 12.4 hours.

After orbital insertion on Aug. 6, Rosetta will initially be travelling in a series of 100 kilometer-long (62 mile-long) triangular arcs in front of the comet while firing thrusters at each apex. Further engine firings will gradually lower Rosetta’s altitude about Comet 67P until the spacecraft is captured by the comet’s gravity.

Rosetta will continue in orbit at comet 67P for a 17 month long study.

In November 2014, Rosetta will attempt another historic first when it deploys the piggybacked Philae science lander from an altitude of just about 2.5 kilometers above the comet for the first ever attempt to land on a comet’s nucleus. The lander will fire harpoons to anchor itself to the 4 kilometer (2.5 mile) wide comet’s surface.

Together, Rosetta and Philae will investigate how the pristine frozen comet composed of ice and rock is transformed by the warmth of the Sun. They will also search for organic molecules, nucleic acids and amino acids, the building blocks for life as we know it.

Rosetta was launched on 2 March 2004 on an Ariane 5 G+ rocket from Europe’s spaceport in Kourou, French Guiana.

Ken Kremer

August 4, 2014December 23, 2015 by Ken Kremer

Rosetta Probe Swoops Closer to Comet Destination than ISS is to Earth and Reveals Exquisite Views

NAVCAM image taken on 3 August 2014 from a distance of about 300 km from comet 67P/Churyumov-Gerasimenko. The Sun is towards the bottom of the image in this orientation. Credits: ESA/Rosetta/NAVCAM

Europe’s Rosetta comet hunter achieved another milestone today, Aug 4, swooping in closer to its long sought destination than the International Space Station (ISS) is to Earth – and its revealing the most exquisitely sharp and detailed view yet of the never before visited icy wanderer soaring half a billion kilometers from the Sun.

The absolutely delightful photo above is the latest navcam taken of Comet 67P/Churyumov-Gerasimenko by Rosetta’s navcam camera on Aug. 3 from a distance of 300 kilometers and shows rocks, gravel and tiny crater like features on its craggily surface of smooth and rough terrain with deposits of water ice.

Rosetta will make history as Earth’s first probe ever to rendezvous with and enter orbit around a comet.

Now barely a day away from rendezvous, the European Space Agency’s (ESA) robotic Rosetta spacecraft has closed to a distance of less than 300 kilometers away from Comet 67P and the crucial orbital insertion engine firing.

By comparison, the ISS and its six person crew orbits Earth at an altitude of some 400 kilometers (about 250 miles).

And its getter even closer! – Essentially to what we would call ‘the edge of space’ on Earth; 100 kilometers or 62 miles.

Having successfully completed the penultimate orbit correction maneuver on Aug. 3, the engineering team at mission control at the European Space Operations Centre (ESOC), in Darmstadt, Germany is making final preparations for the probes crucial last orbital insertion burn set for Wednesday, Aug. 6.

The Aug. 3 thruster firing known as the Close Approach Trajectory – pre-Insertion (CATP) burn lasted some 13 minutes and 12 seconds and reduced the spacecraft speed as planned by about 3.2 m/s.

“All looks good,” says Rosetta Spacecraft Operations Manager Sylvain Lodiot, according to an ESA operations tweet.

The final thruster firing upcoming soon on Aug. 6 is known as the Close Approach Trajectory – Insertion (CATI) burn.

The CATI orbit insertion firing will slow Rosetta to essentially the same speed as comet 67P and place it in an initial orbit at a distance of about 100 kilometers (62 miles).

The CATP and CATI trajectory firings have the combined effect of slowing Rosetta’s speed by some 3.5 m/s with respect to the comet which is traveling at 55,000 kilometers per hour (kph).

After a ten year chase of 6.4 billion kilometers (4 Billion miles) through interplanetary space and slingshots past Earth and Mars, the 1.3 Billion Euro spacecraft is at last ready to arrive at Comet 67P for a mission expected to last some 17 months.

The Navcam camera has been commanded to capture daily images of the comet that rotates around once every 12.4 hours.

See below our mosaic of navcam camera approach images of the nucleus captured of the mysterious two lobed comet, merged at a bright band in between as well as an OSIRIS camera image of the expanding coma cloud of water and dust..

After orbital inertion on Aug. 6, Rosetta will initially be travelling in a series of 100 kilometer-long triangular arcs while firings thrusters at each apex. Further engine firings will gradually lower Rosetta’s altitude about Comet 67P until the spacecraft is captured by the comet’s gravity.

Here is an ESA video showing Rosetta’s movements around the comet after arrival

Video caption: ESA’s Rosetta spacecraft will reach comet 67P/Churyumov-Gerasimenko in August 2014. After catching up with the comet Rosetta will slightly overtake and enter orbit from the ‘front’ of the comet as both the spacecraft and 67P/CG move along their orbits around the Sun. Rosetta will carry out a complex series of manoeuvres to reduce the separation between the spacecraft and comet from around 100 km to 25-30 km. Credit: ESA

Rosetta was launched on 2 March 2004 on an Ariane 5 G+ rocket from Europe’s spaceport in Kourou, French Guiana.

You can watch Rosetta’s Aug. 6 orbital arrival live from 10:45-11:45 CEST via a livestream transmission from ESA’s spacecraft operations centre in Darmstadt, Germany.

Ken Kremer

August 4, 2014December 23, 2015 by Jason Major

If the Sun Were the Size of a Person, How Big Would an Asteroid Be?

Artist's concept of OSIRIS-REx at Bennu. (Credit: NASA/GSFC)

I love anything that attempts to provide a sense of scale about the Solar System (see here and here for even more examples) and this one brings us down past the Sun, planets, and moons all the way to asteroid size — specifically asteroid 101955 Bennu, the target of the upcoming OSIRIS-REx mission.

Created by the OSIRIS-REx “321Science!” team, consisting of communicators, film and graphic arts students, teens, scientists, and engineers, the video shows some relative scales of our planet compared to the Sun, and also the actual size of asteroid Bennu in relation to some familiar human-made structures that we’re familiar with. (My personal take-away from this: Bennu — one of those “half grains of sand” — is a rather small target!)

A NASA New Frontiers mission, OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) will launch in Sept. 2016 on a two-year journey to the asteroid 101955 Bennu. Upon arrival OSIRIS-REx will map Bennu’s surface and also measure the Yarkovsky effect, by which asteroids’ trajectories can change over time due to the small force exerted by radiant heat.

OSIRIS-REx will also attempt to collect and send back a 60-gram sample of the asteroid’s surface material. Learn more about the OSIRIS-REx mission here and here.

August 3, 2014December 23, 2015 by Ken Kremer

Rosetta Orbiter less than 500 Kilometers from Comet 67P Following Penultimate Trajectory Burn

The Rosetta comet chaser is currently less than 500 kilometers (300 miles) from its target destination, Comet 67P/Churyumov-Gerasimenko following today’s (Aug. 3) successful completion of the spacecraft’s critically important penultimate trajectory burn, just three days before its history making arrival at the comet on Aug. 6.

The European Space Agency’s (ESA) 1.3 Billion euro Rosetta spacecraft is now under three days away from becoming Earth’s first probe ever to rendezvous with and enter orbit around a comet after a decade long hunt of 6.4 billion kilometers (4 Billion miles) through interplanetary space. The gap is narrowing with each passing second.

The last trajectory firing is set for Aug. 6. Altogether the final pair of trajectory burns will reduce the spacecrafts speed by some 3.5 meters per second (m/s) with respect to the comet which is traveling at 55,000 kilometers per hour (kph).

The probes latest Navcam camera image shot on Aug. 2, 2014 from a distance of about 500 kilometers from comet 67P/Churyumov-Gerasimenko shows exquisite detail of the rubber ducky shaped body tumbling end over end. See above.

See below our mosaic of navcam camera approach images of the nucleus captured over the past week and a half of the mysterious two lobed comet, merged at a bright band in between.

In November 2014, the Rosetta mothership will attempt another historic first when it deploys the Philae science lander from an altitude of just 1 or 2 kilometers for the first ever attempt to land on a comet’s nucleus. The lander will fire harpoons to anchor itself to the 4 kilometer wide (2.5 mile) comet’s surface.

Did life on Earth begin with the help of comet seeding? That’s a question the Rosetta science team seeks to help answer.

Today’s early morning thruster firing, officially known as the Close Approach Trajectory – pre-Insertion (CATP) burn, began as scheduled at 11:00 CEST (09:00 GMT) and was due to last for about 13 minutes and 12 seconds and bleed off some 3.2 m/s of spacecraft speed.

Although it ended a few seconds early, ESA reports that the CATP burn went well as engineers monitored the spacecraft communications at the European Space Operations Centre (ESOC), in Darmstadt, Germany via the agency’s 35 meter deep-space tracking station in New Norcia, Australia.

“All looks good,” says Rosetta Spacecraft Operations Manager Sylvain Lodiot, according to an ESA operations tweet.

CATP is part of the final series of ten orbit correction maneuvers (OCM’s) that culminates with the final thruster firing slated for Aug. 6 dubbed the Close Approach Trajectory – Insertion (CATI) burn.

“The CATI burn will reduce the relative velocity to about 1 m/s,” says Lodiot. That’s about equivalent to human walking speed.

The CATI orbit insertion firing will slow Rosetta to essentially the same speed as a comet and place it in orbit at an initial stand-off distance of about 100 kilometers (62 miles).

Rosetta will initially be travelling in a series of 100 kilometer-long triangular arcs while firings thrusters at each apex. Further engine firings will gradually lower Rosetta’s altitude about Comet 67P until the spacecraft is captured by the comet’s gravity.

“All systems on the spacecraft are performing well and the entire team is looking forward to a smooth arrival,” says Lodiot.

It will study and map the wanderer composed of primordial ice, rock, dust and more and search for a suitable landing site for Philae.

The one-way signal time from Earth to Rosetta and Comet 67P is currently 22 minutes and 27 seconds as both loop around the Sun at a distance of some 555 million kilometres away from the Sun at this time. The short period comet is located between the orbits of Jupiter and Mars.

Rosetta will escort Comet 67P as they journey together inwards around the sun and then travel back out towards Jupiter’s orbit and investigate the physical properties and chemical composition of the comets nucleus and coma of ice and dust for some 17 months.

Rosetta was launched on 2 March 2004 on an Ariane 5 G+ rocket from Europe’s spaceport in Kourou, French Guiana.

You can watch Rosetta’s Aug. 6 orbital arrival live from 10:45-11:45 CEST via a livestream transmission from ESA’s spacecraft operations centre in Darmstadt, Germany.

Ken Kremer

August 3, 2014December 23, 2015 by Ken Kremer

Ranger 7 Takes 1st Image of the Moon by a US Spacecraft 50 Years Ago – July 31, 1964

Ranger 7 took this image, the first picture of the Moon by a U.S. spacecraft, on 31 July 1964 at 13:09 UT (9:09 AM EDT) about 17 minutes before impacting the lunar surface. Credit: NASA/JPL-Caltech

As we remember the 45th anniversary of Earth’s historic 1st manned lunar landing last week by America’s Apollo 11 crew of Neil Armstrong and Buzz Aldrin on July 20, 1969, it’s likewise well worth recalling NASA’s pioneering and historic unmanned robotic mission Ranger 7 – that led the way to the Moon almost exactly 5 years earlier and that paved the path for the eventual 1st human footsteps on another celestial body.

Indeed the first critical robotic step to the manned landings was successfully taken when NASA’s unmanned Ranger 7 probe captured the first image of the Moon by a U.S. spacecraft 50 Years ago on July 31, 1964.

Ranger 7 took the milestone maiden picture of the Moon by an American spacecraft, on 31 July 1964, shown above, at 13:09 GMT (9:09 AM EDT) about 17 minutes before impacting the lunar surface on a suicide dive.

The history making image was taken at an altitude of 2110 kilometers and is centered at 13 S, 10 W and covers about 360 kilometers from top to bottom. The large Alphonsus crater is at center right and 108 km in diameter. Ptolemaeus crater is above and Arzachel is below.

Ranger 7 impacted out of view of the lead image, off to the left of the upper left corner.

“It looks as though this particular shot has been indeed a textbook operation,” William H. Pickering, the director of JPL during the mission, said at the time.

Guericke Crater as seen by Ranger 7. Ranger 7 B-camera image of Guericke crater (11.5 S, 14.1 W, diameter 63 km) taken from a distance of 1335 km. The dark flat floor of Mare Nubium dominates most of the image, which was taken 8.5 minutes before Ranger 7 impacted the Moon on 31 July 1964. The frame is about 230 km across and north is at 12:30. The impact site is off the frame to the left. Credit: NASA/JPL-Caltech — Guericke Crater as seen by Ranger 7
Ranger 7 B-camera image of Guericke crater (11.5 S, 14.1 W, diameter 63 km) taken from a distance of 1335 km. The dark flat floor of Mare Nubium dominates most of the image, which was taken 8.5 minutes before Ranger 7 impacted the Moon on 31 July 1964. The frame is about 230 km across and north is at 12:30. The impact site is off the frame to the left. Credit: NASA/JPL-Caltech

The purpose of NASA’s robotic Ranger program was to take high-quality pictures of the Moon and transmit them back to Earth in real time before being decimated on impact.

NASA Ranger 7 spacecraft. Credit: NASA/JPL-Caltech

The priceless pictures would be used for science investigations as well as to search for suitable landing sites for NASA’s then planned Apollo manned Moon landers.

It’s hard to conceive now, but 5 decades ago at the dawn of the Space Age no one knew what the surface of the Moon was really like. There were vigorous debates back then on whether it was even hard or soft. Was it firm? Would a landed spacecraft or human astronaut sink?

Last Ranger 7 images taken before impact on the Moon. They were taken by the number 1 and 3 P-channel cameras at 0.39 and 0.19 s before impact from an altitude of 1070 and 519 meters, respectively. The pictures are cut off because the spacecraft impacted the surface before completing the transmission. The top image was taken by the P3 camera and the bottom image by P1. The P3 image is about 25 m across. North is at 12:30 for both images. The impact occurred on 31 July 1964 at 13:25:48.82 UT. Credit: Credit: NASA/JPL-Caltech — Last Ranger 7 images taken before impact on the Moon. They were taken by the number 1 and 3 P-channel cameras at 0.39 and 0.19 s before impact from an altitude of 1070 and 519 meters, respectively. The pictures are cut off because the spacecraft impacted the surface before completing the transmission. The top image was taken by the P3 camera and the bottom image by P1. The P3 image is about 25 m across. North is at 12:30 for both images. The impact occurred on 31 July 1964 at 13:25:48.82 UT. Credit: NASA/JPL-Caltech

Altogether the probe took 4,308 excellent quality pictures during its final 17 minutes before crashing into the Moon at 13:26 GMT (9:26 p.m. EDT) in an area between Mare Nubium and Oceanus Procellarum at a spot subsequently named Mare Cognitum at 10.63 S latitude, 20.60 W longitude.

The final image from Ranger 7 shown herein had a resolution of 0.5 meter/pixel.

Ranger 7 was launched atop an Atlas Agena B rocket on 28 July 1964 from what was then known as Cape Kennedy and smashed into our nearest neighbor after 68.6 hours of flight at a velocity of 2.62 km/s (1.62 miles per second).

The 365.7 kilogram (806 lb) vehicle was 4.5 m wide and stood 3.6 m (11 ft) tall and was the Block 3 version of the Ranger spacecraft. It was powered by a pair of 1.5 m long solar panels and was equipped with a science payload of six television vidicon cameras transmitting data via the pointable high gain antennae mounted at the base.

Ranger 7 was the first successful mission in the Ranger series. The flight was entirely successful and was followed by Ranger’s 8 and 9. They were built by NASA’s Jet Propulsion Laboratory, Pasadena, California.

Here’s a short 1964 documentary chronicling Ranger 7 titled “Lunar Bridgehead” that truly harkens back to the 1950s and 1960s and sci fi movies of the time. No wonder since that’s when it was produced.

Video Caption. This 1964 documentary titled “Lunar Bridgehead produced by NASA’s Jet Propulsion Laboratory, Pasadena, California, chronicles the moments leading up to and following the Ranger 7 mission’s lunar impact 50 years ago. Credit: NASA/JPL-Caltech

During the 1960’s NASA implemented an ambitions three pronged strategy of robotic missions – including Ranger, Lunar Orbiter and Surveyor – that imaged the Moon and studied it’s physical and chemical properties and supported and enabled the Apollo program and led directly to Neil Armstrong stepping onto the alien lunar landscape.

Three members of the Ranger 7 television experiment team stand near a scale model and lunar globe at NASA’s Jet Propulsion Laboratory (JPL). From left: Ewen Whitaker, Dr. Gerard Kuiper, and Ray Heacock. Kuiper was the director of the Lunar and Planetary Laboratory (LPL) at the University of Arizona. Whitaker was a research associate at LPL. Heacock was the Lunar and Planetary Instruments section chief at JPL. Credit: NASA/JPL-Caltech

Read more about pathfinding space missions in my earlier space history story about Mariner 10 – the first space probe to ever carry out a planetary gravity assist maneuver used to alter its speed and trajectory – in order to reach another celestial body – here.

Read my 45th Apollo 11 anniversary articles here:

Apollo 11 Splashdown 45 Years Ago on July 24, 1969 Concludes 1st Moon Landing Mission – Gallery

Historic Human Spaceflight Facility at Kennedy Renamed in Honor of Neil Armstrong – 1st Man on the Moon

Apollo 11 Moon Landing 45 Years Ago on July 20, 1969: Relive the Moment! – With an Image Gallery and Watch the Restored EVA Here

Book Review: Neil Armstrong – A Life of Flight by Jay Barbree

Stay tuned here for Ken’s Earth & Planetary science and human spaceflight news.

Ken Kremer