Monday, October 31, 2016

Images of the Day: Destroying the Invincible...

Attacking the Star Destroyer Invincible after I destroyed its two shield generators during Tour of Duty 1: Mission 3 in the STAR WARS: X-WING video game.

Happy Halloween, everyone!! Nothing's cooler (unless I actually had my life priorities straight) than blowing up a Star Destroyer during a mission in which I don't need to blow it up in order to achieve the objectives at hand. That would be Tour of Duty 1: Mission 3 in the Star Wars: X-Wing video game. Yes, two years after I've purchased it online, I still play this awesome game on my laptop. Death to the Invincible!

Needless to say, Tour of Duty 1: Mission 3 was a huge success.

Thursday, October 27, 2016

New Horizons Update: All Data From The Pluto Flyby Have Been Sent Home!

An artist's concept of NASA's New Horizons spacecraft transmitting data back to Earth.
NASA / JHUAPL / SwRI

New Horizons Returns Last Bits of 2015 Flyby Data to Earth (News Release)

NASA’s New Horizons mission reached a major milestone this week when the last bits of science data from the Pluto flyby – stored on the spacecraft’s digital recorders since July 2015 – arrived safely on Earth.

Having traveled from the New Horizons spacecraft over 3.4 billion miles, or 5.5 billion kilometers (five hours, eight minutes at light speed), the final item – a segment of a Pluto-Charon observation sequence taken by the Ralph/LEISA imager – arrived at mission operations at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, at 5:48 a.m. EDT on Oct. 25. The downlink came via NASA’s Deep Space Network station in Canberra, Australia. It was the last of the 50-plus total gigabits of Pluto system data transmitted to Earth by New Horizons over the past 15 months.

“The Pluto system data that New Horizons collected has amazed us over and over again with the beauty and complexity of Pluto and its system of moons,” said Alan Stern, New Horizons principal investigator from Southwest Research Institute in Boulder, Colorado. “There’s a great deal of work ahead for us to understand the 400-plus scientific observations that have all been sent to Earth. And that’s exactly what we’re going to do—after all, who knows when the next data from a spacecraft visiting Pluto will be sent?”

Because it had only one shot at its target, New Horizons was designed to gather as much data as it could, as quickly as it could – taking about 100 times more data on close approach to Pluto and its moons than it could have sent home before flying onward. The spacecraft was programmed to send select, high-priority datasets home in the days just before and after close approach, and began returning the vast amount of remaining stored data in September 2015.

“We have our pot of gold,” said Mission Operations Manager Alice Bowman, of APL.

Bowman said the team will conduct a final data-verification review before erasing the two onboard recorders, and clearing space for new data to be taken during the New Horizons Kuiper Belt Extended Mission (KEM) that will include a series of distant Kuiper Belt object observations and a close encounter with a small Kuiper Belt object, 2014 MU69, on Jan. 1, 2019.

Source: NASA.Gov

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The green line marks the path traveled by the New Horizons spacecraft as of 4:00 PM, Pacific Daylight Time, on October 27, 2016.  It is 3.5 billion miles from Earth.
ABOVE: The green line marks the path traveled by the New Horizons spacecraft as of 4:00 PM, Pacific Daylight Time, on October 27, 2016. It is 3.5 billion miles from Earth. Click here to view the official webpage showing where New Horizons is in space. (AU stands for Astronomical Units, in case you're wondering.)

Saturday, October 22, 2016

The Red Planet As Seen In Ultraviolet...

An ultraviolet image of Mars that was taken by NASA's MAVEN spacecraft on July 9-10, 2016.
NASA / MAVEN / University of Colorado

NASA's MAVEN Mission Gives Unprecedented Ultraviolet View of Mars (Press Release - October 17)

New global images of Mars from the MAVEN mission show the ultraviolet glow from the Martian atmosphere in unprecedented detail, revealing dynamic, previously invisible behavior. They include the first images of "nightglow" that can be used to show how winds circulate at high altitudes. Additionally, dayside ultraviolet imagery from the spacecraft shows how ozone amounts change over the seasons and how afternoon clouds form over giant Martian volcanoes. The images were taken by the Imaging UltraViolet Spectrograph (IUVS) on the Mars Atmosphere and Volatile Evolution mission (MAVEN).

"MAVEN obtained hundreds of such images in recent months, giving some of the best high-resolution ultraviolet coverage of Mars ever obtained," said Nick Schneider of the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder. Schneider is presenting these results Oct. 19 at the American Astronomical Society Division for Planetary Sciences meeting in Pasadena, California.

Nightside images show ultraviolet (UV) "nightglow" emission from nitric oxide (abbreviated NO). Nightglow is a common planetary phenomenon in which the sky faintly glows even in the complete absence of external light. Mars' nightside atmosphere emits light in the ultraviolet due to chemical reactions that start on Mars' dayside. Ultraviolet light from the sun breaks down molecules of carbon dioxide and nitrogen, and the resulting atoms are carried around the planet by high-altitude wind patterns that encircle the planet. On the nightside, these winds bring the atoms down to lower altitudes where nitrogen and oxygen atoms collide to form nitric oxide molecules. The recombination releases extra energy, which comes out as ultraviolet light.

Scientists predicted NO nightglow at Mars, and prior missions detected its presence, but MAVEN has returned the first images of this phenomenon in the Martian atmosphere. Splotches and streaks appearing in these images occur where NO recombination is enhanced by winds. Such concentrations are clear evidence of strong irregularities in Mars' high altitude winds and circulation patterns. These winds control how Mars' atmosphere responds to its very strong seasonal cycles. These first images will lead to an improved determination of the circulation patterns that control the behavior of the atmosphere from approximately 37 to 62 miles (about 60 to 100 kilometers) high.

Dayside images show the atmosphere and surface near Mars' south pole in unprecedented ultraviolet detail. They were obtained as spring comes to the southern hemisphere. Ozone is destroyed when water vapor is present, so ozone accumulates in the winter polar region where the water vapor has frozen out of the atmosphere. The images show ozone lasting into spring, indicating that global winds are inhibiting the spread of water vapor from the rest of the planet into winter polar regions. Wave patterns in the images, revealed by UV absorption from ozone concentrations, are critical to understanding the wind patterns, giving scientists an additional means to study the chemistry and global circulation of the atmosphere.

MAVEN observations also show afternoon cloud formation over the four giant volcanoes on Mars, much as clouds form over mountain ranges on Earth. IUVS images of cloud formation are among the best ever taken showing the development of clouds throughout the day. Clouds are a key to understanding a planet's energy balance and water vapor inventory, so these observations will be valuable in understanding the daily and seasonal behavior of the atmosphere.

"MAVEN's elliptical orbit is just right," said Justin Deighan of the University of Colorado, Boulder, who led the observations. "It rises high enough to take a global picture, but still orbits fast enough to get multiple views as Mars rotates over the course of a day."

MAVEN's principal investigator is based at the University of Colorado's Laboratory for Atmospheric and Space Physics, Boulder. The university provided two science instruments and leads science operations, as well as education and public outreach, for the mission. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the MAVEN project and provided two science instruments for the mission. The University of California at Berkeley's Space Sciences Laboratory also provided four science instruments for the mission. Lockheed Martin built the spacecraft and is responsible for mission operations. NASA's Jet Propulsion Laboratory in Pasadena, California, provides navigation and Deep Space Network support, as well as the Electra telecommunications relay hardware and operations.

Source: NASA.Gov

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Martian hemispheres as seen in the ultraviolet by NASA's MAVEN spacecraft on July 9-10, 2016.
NASA / MAVEN / University of Colorado

Friday, October 21, 2016

ExoMars Update: The Fate of Schiaparelli Is Revealed...

An animated GIF showing Schiaparelli's crash site on the Red Planet...comprised of photos taken by NASA's Mars Reconnaissance Orbiter on May 29 and October 20, 2016.
NASA / JPL - Caltech / MSSS

Camera on Mars Orbiter Shows Signs of Latest Mars Lander (Press Release)

NASA's Mars Reconnaissance Orbiter has identified new markings on the surface of the Red Planet that are believed to be related to Europe's Schiaparelli test lander, which arrived at Mars on Oct. 19.

The new image shows a bright spot that may be Schiaparelli's parachute, and a larger dark spot interpreted as resulting from the impact of the lander itself following a much longer free fall than planned, after thrusters switched off prematurely. It was taken by the Context Camera (CTX) on NASA's Mars Reconnaissance Orbiter and is available online, as a before-and-after comparison with an image from May 2016, at:

http://mars.nasa.gov/multimedia/images/?ImageID=8131

The location information gained from acquiring the CTX image will be used for imaging the site with the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (HiRISE) camera. European Space Agency (ESA) and NASA researchers will analyze the images for information about the sequence of events on Schiaparelli's landing day, possibly supplementing data transmitted from the test module during its descent.

The location of the bright spot interpreted as the parachute is 353.79 degrees east longitude, 2.07 degrees south latitude, closely matching ESA's calculation for the landing location based on landing-day data. This is within the planned landing area and about 3.3 miles (5.4 kilometers) west of the center of the landing target. A dark spot is larger and elliptical, approximately 50 by 130 feet (15 by 40 meters). It may be where the lander reached the surface and exposed darker ground.

The test lander is part of ESA's ExoMars 2016 mission, which placed the Trace Gas Orbiter into orbit around Mars on Oct. 19. The orbiter will investigate Mars' atmosphere and provide relay communications capability for landers and rovers on the surface.

With CTX, HiRISE and four other instruments, the Mars Reconnaissance Orbiter has been investigating Mars since 2006.

Malin Space Science Systems, San Diego, built and operates CTX. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter and collaborates with JPL to operate it.

Source: Jet Propulsion Laboratory

Thursday, October 20, 2016

New Horizons Update: Getting First Details on 2014 MU69...

An artist's concept of NASA's New Horizons spacecraft flying past a Kuiper Belt Object.
NASA / Johns Hopkins University Applied Physics Laboratory / Southwest Research Institute

New Horizons: Possible Clouds on Pluto, Next Target is Reddish (News Release - October 18)

The next target for NASA’s New Horizons mission – which made a historic flight past Pluto in July 2015 –– apparently bears a colorful resemblance to its famous, main destination.

Hubble Space Telescope data suggests that 2014 MU69, a small Kuiper Belt object (KBO) about a billion miles (1.6 billion kilometers) beyond Pluto, is as red, if not redder, than Pluto. This is the first hint at the surface properties of the far flung object that New Horizons will survey on Jan. 1, 2019.

Mission scientists are discussing this and other Pluto and Kuiper Belt findings this week at the American Astronomical Society Division for Planetary Sciences (DPS) and European Planetary Science Congress (EPSC) in Pasadena, California.

“We’re excited about the exploration ahead for New Horizons, and also about what we are still discovering from Pluto flyby data,” said Alan Stern, principal investigator from Southwest Research Institute in Boulder, Colorado. “Now, with our spacecraft transmitting the last of its data from last summer’s flight through the Pluto system, we know that the next great exploration of Pluto will require another mission to be sent there.”

Stern said that Pluto’s complex, layered atmosphere is hazy and appears to be mostly free of clouds, but the team has spied a handful of potential clouds in images taken with New Horizons’ cameras. “If there are clouds, it would mean the weather on Pluto is even more complex than we imagined,” Stern said.

Scientists already knew from telescope observations that Pluto’s icy surface below that atmosphere varied widely in brightness. Data from the flyby not only confirms that, it also shows the brightest areas (such as sections of Pluto’s large heart-shaped region) are among the most reflective in the solar system. “That brightness indicates surface activity,” said Bonnie Buratti, a science team co-investigator from NASA’s Jet Propulsion Laboratory in Pasadena. “Because we see a pattern of high surface reflectivity equating to activity, we can infer that the dwarf planet Eris, which is known to be highly reflective, is also likely to be active.”

While Pluto shows many kinds of activity, one surface process apparently missing is landslides. Surprisingly, though, they have been spotted on Pluto’s largest moon, Charon, itself some 750 miles (1,200 kilometers) across. “We’ve seen similar landslides on other rocky and icy planets, such as Mars and Saturn’s moon Iapetus, but these are the first landslides we’ve seen this far from the sun, in the Kuiper Belt,” said Ross Beyer, a science team researcher from Sagan Center at the SETI Institute and NASA Ames Research Center, California. “The big question is will they be detected elsewhere in the Kuiper Belt?”

Both Hubble and cameras on the New Horizons spacecraft have been aimed at KBOs over the past two years, with New Horizons taking advantage of its unique vantage point in the Kuiper Belt to observe nearly a dozen small worlds in this barely explored region. MU69 is actually the smallest KBO to have its color measured – and scientists have used that data to confirm the object is part of the so-called cold classical region of the Kuiper Belt, which is believed to contain some of the oldest, most prehistoric material in the solar system.

“The reddish color tells us the type of Kuiper Belt object 2014 MU69 is,” said Amanda Zangari, a New Horizons post-doctoral researcher from Southwest Research Institute. “The data confirms that on New Year’s Day 2019, New Horizons will be looking at one of the ancient building blocks of the planets.”

The New Horizons spacecraft is currently 3.4 billion miles (5.5 billion kilometers) from Earth and about 340 million miles (540 million kilometers) beyond Pluto, speeding away from the sun at about nine miles (14 kilometers) every second. About 99 percent of the data New Horizons gathered and stored on its digital recorders during the Pluto encounter has now been transmitted back to Earth, with that transmission set to be completed Oct. 23. New Horizons has covered about one-third of the distance from Pluto to its next flyby target, which is now about 600 million miles (nearly 1 billion kilometers) ahead.

The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft, and manages the mission for NASA's Science Mission Directorate. In addition to being the home of the mission principal investigator, SwRI, based in San Antonio, leads the science team, payload operations and science planning. New Horizons is the first mission in NASA's New Frontiers Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

Source: NASA.Gov

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The green line marks the path traveled by the New Horizons spacecraft as of 2:00 PM, Pacific Daylight Time, on October 20, 2016.  It is 3.4 billion miles from Earth.
ABOVE: The green line marks the path traveled by the New Horizons spacecraft as of 2:00 PM, Pacific Daylight Time, on October 20, 2016. It is 3.4 billion miles from Earth. Click here to view the official webpage showing where New Horizons is in space. (AU stands for Astronomical Units, in case you're wondering.)

Wednesday, October 19, 2016

ExoMars Update: Orbiting The Red Planet Is Easy; Landing, On The Other Hand...

An artist's concept of Europe's Trace Gas Orbiter releasing the Schiaparelli demonstrator module towards Mars.
ESA – D. Ducros

ExoMars TGO Reaches Mars Orbit While EDM Situation Under Assessment (Press Release)

The Trace Gas Orbiter (TGO) of ESA’s ExoMars 2016 has successfully performed the long 139-minute burn required to be captured by Mars and entered an elliptical orbit around the Red Planet, while contact has not yet been confirmed with the mission’s test lander from the surface.

TGO’s Mars Orbit Insertion burn lasted from 13:05 to 15:24 GMT on 19 October, reducing the spacecraft’s speed and direction by more than 1.5 km/s. The TGO is now on its planned orbit around Mars. European Space Agency teams at the European Space Operations Centre (ESOC) in Darmstadt, Germany, continue to monitor the good health of their second orbiter around Mars, which joins the 13-year old Mars Express.

The ESOC teams are trying to confirm contact with the Entry, Descent & Landing Demonstrator Module (EDM), Schiaparelli, which entered the Martian atmosphere some 107 minutes after TGO started its own orbit insertion manoeuvre.

The 577-kg EDM was released by the TGO at 14:42 GMT on 16 October. Schiaparelli was programmed to autonomously perform an automated landing sequence, with parachute deployment and front heat shield release between 11 and 7 km, followed by a retrorocket braking starting at 1100 m from the ground, and a final fall from a height of 2 m protected by a crushable structure.

Prior to atmospheric entry at 14:42 GMT, contact via the Giant Metrewave Radio Telescope (GMRT), the world’s largest interferometric array, located near Pune, India, was established just after it began transmitting a beacon signal 75 minutes before reaching the upper layers of the Martian atmosphere. However, the signal was lost some time prior to landing.

A series of windows have been programmed to listen for signals coming from the lander via ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter (MRO) and Mars Atmosphere & Volatile Evolution (MAVEN) probes. The Giant Metrewave Radio Telescope (GMRT) also has listening slots.

If Schiaparelli reached the surface safely, its batteries should be able to support operations for three to ten days, offering multiple opportunities to re-establish a communication link.

TGO is equipped with a suite of science instruments in order to study the Martian environment from orbit. Although mostly a technology demonstrator, Schiaparelli is also carrying a small science payload to perform some observations from ground.

ExoMars 2016 is the first part of a two-fold international endeavour conducted by ESA in cooperation with Roskosmos in Russia that will also encompass the ExoMars 2020 mission. Due in 2020, the second ExoMars mission will include a Russian lander and a European rover, which will drill down to 2 m underground to look for pristine organic material.

Source: European Space Agency

Tuesday, October 18, 2016

Election 2016: I'm (Officially) With Her...

My absentee ballot for the 2016 U.S. presidential election has been mailed.

Just thought I'd mention that I finally mailed my absentee ballot for this year's American presidential election. Woohoo, it feels so good to vote! Despite the fact that the final presidential debate takes place in Las Vegas tomorrow, I don't need to spend another 90 minutes (which, like the first two debates, I'll do anyway) hearing Donald Trump spout lie after lie about his (still-secret) tax returns, his misogynistic behavior towards women and the supposed endorsement that he received from 200 admirals and generals in the U.S. military (they need to be court-martialed if this were true) to vote Democrat. And let's not forget his constant verbal fellating of Russian president Vladimir Putin and even Iran in regards to the war against the Islamic State. Go Hillary! Also, the image below shows my not-so-subtle response to Trump's assertion that the election will be rigged. Oh, it'll be rigged alright...but in the sense that rational American citizens and global opinion are doing everything they can to prevent this man from ever setting foot in the Oval Office, and not because of voter fraud.

I implore my fellow Californians to register to vote by October 24 by clicking on this website—and make sure that a sniffling, "Bigly"-spouting demagogue like Trump never makes it to the White House, let alone being allowed to walk along Pennsylvania Avenue ever again. Register to vote now!

This is for YOU, Trump... Rigged election, my ass.

Monday, October 17, 2016

T-Minus 2 Days and Counting: Europe (and Russia) Set to Enter Orbit and Land on Mars...

An image of the Red Planet that was taken by Europe's Mars Express spacecraft on October 16, 2016.
ESA – CC BY - SA 3.0 IGO

The Red Planet Welcomes ExoMars (Press Release)

Mars as seen by the webcam on ESA’s Mars Express orbiter on 16 October 2016, as another mission, ExoMars, is about to reach the Red Planet.

A joint endeavour between ESA and Russia’s Roscosmos space agency, ExoMars 2016 comprises the Trace Gas Orbiter and the Schiaparelli entry, descent and landing demonstrator. After a seven-month journey, the two spacecraft are closing in on their destination, with the main craft entering orbit around Mars and Schiaparelli landing on 19 October.

This image was taken on 16 October, a couple of hours before Schiaparelli separated from its mothership at 16:42 GMT. Following separation, Schiaparelli still has three days and some six million km to travel before entering the atmosphere on 19 October for a six-minute descent to a region in Meridiani Planum, close to the planet’s equator.

This recent view of the planet shows its southern pole, covered by a permanent ice cap consisting mainly of carbon dioxide. The target region for Schiaparelli’s landing is not visible, beyond the horizon on the left.

ExoMars will arrive when the planet is almost at its closest point to the Sun along its orbit, and during northern winter (southern summer). At this time in the year, wind speeds are likely to increase and could lead to regional or even global dust storms.

The image was taken with Mars Express’s simple, wide-angle camera, which was originally meant only to provide visual confirmation that its Beagle-2 lander had separated when they arrived at Mars in December 2003. Switched back on in 2007, the camera has since been used for outreach, education and citizen-science, and was eventually adopted as a professional science instrument by ESA earlier this year.

With its unique vantage point and wide field of view, this webcam can capture global images of the Red Planet, a capability currently available only on one other spacecraft operating there, India’s Mars Orbiter Mission.

Mars can be seen from Earth at the moment: it is visible as a red spot to the naked eye, low on the horizon towards the south in the early evening skies from the northern hemisphere, and reaching higher elevations in the evenings and early mornings from the southern hemisphere.

Amateur astronomers observing the Red Planet with a telescope can join the Mars focus group of the Pro-Am Collaborative Astronomy project, an international group sharing images of specific astronomical objects and events taken by the amateur community to support professional astronomers.

The Mars observing campaign originally started in 2014 to monitor the passage of Comet Siding Spring near the Red Planet, and later evolved into a group dedicated to observe Mars and to provide the astronomical community with a long timeline of Mars observations, especially during times of dust activity.

Source: European Space Agency

Wednesday, October 12, 2016

Images of the Day: The Seventh Sister...

A true-color image of my Seventh Sister drawing.

Just thought I'd share this illustration that I drew of the Seventh Sister, the 'Sith Inquisitor' who's voiced by Sarah Michelle Gellar on Disney XD's Star Wars Rebels. I've only watched this animated TV show once (it's pretty cool based on what I've seen), but the Seventh Sister herself caught my attention after viewing a Disneyland commercial—which aired around the time of The Force Awakens' theatrical release last December—showing a Cast Member wearing a live-action costume of the villain while engaging in mock lightsaber duels with little kids dressed as Jedi Younglings (see the photo at the very bottom of this entry). It would be so cool if the Seventh Sister made an appearance in Star Wars: Episode VIII or a future film...even though I don't know what her fate was on Star Wars Rebels (and she would be quite old considering that Rebels takes place more than 30 years before Rey and Finn join the Resistance to save the galaxy). Anyways, I can't decide if I should draw a Death Trooper from Rogue One: A Star Wars Story or Captain Phasma as my next artwork. We'll see. Happy Hump Day!

Another image of my Seventh Sister drawing...with some enhancements made via Photoshop.

Work-in-progress photos of my Seventh Sister drawing.

Disneyland Cast Members dressed as Darth Vader and the Seventh Sister.

Saturday, October 01, 2016

Rosetta Joins Philae in the History Books...

An artist's concept of the Rosetta spacecraft about to crash land onto the surface of Comet 67P/Churyumov–Gerasimenko.
ESA / ATG medialab

Mission Complete: Rosetta’s Journey Ends in Daring Descent to Comet (Press Release - September 30)

ESA’s historic Rosetta mission has concluded as planned, with the controlled impact onto the comet it had been investigating for more than two years.

Confirmation of the end of the mission arrived at ESA’s control centre in Darmstadt, Germany at 11:19 GMT (13:19 CEST) with the loss of Rosetta’s signal upon impact.

Rosetta carried out its final manoeuvre last night at 20:50 GMT (22:50 CEST), setting it on a collision course with the comet from an altitude of about 19 km. Rosetta had targeted a region on the small lobe of Comet 67P/Churyumov–Gerasimenko, close to a region of active pits in the Ma’at region.

The descent gave Rosetta the opportunity to study the comet’s gas, dust and plasma environment very close to its surface, as well as take very high-resolution images.

Pits are of particular interest because they play an important role in the comet’s activity. They also provide a unique window into its internal building blocks.

The information collected on the descent to this fascinating region was returned to Earth before the impact. It is now no longer possible to communicate with the spacecraft.

“Rosetta has entered the history books once again,” says Johann-Dietrich Wörner, ESA’s Director General. “Today we celebrate the success of a game-changing mission, one that has surpassed all our dreams and expectations, and one that continues ESA’s legacy of ‘firsts’ at comets.”

“Thanks to a huge international, decades-long endeavour, we have achieved our mission to take a world-class science laboratory to a comet to study its evolution over time, something that no other comet-chasing mission has attempted,” notes Alvaro Giménez, ESA’s Director of Science.

“Rosetta was on the drawing board even before ESA’s first deep-space mission, Giotto, had taken the first image of a comet nucleus as it flew past Halley in 1986.

“The mission has spanned entire careers, and the data returned will keep generations of scientist busy for decades to come.”

“As well as being a scientific and technical triumph, the amazing journey of Rosetta and its lander Philae also captured the world’s imagination, engaging new audiences far beyond the science community. It has been exciting to have everyone along for the ride,” adds Mark McCaughrean, ESA’s senior science advisor.

Since launch in 2004, Rosetta is now in its sixth orbit around the Sun. Its nearly 8 billion-kilometre journey included three Earth flybys and one at Mars, and two asteroid encounters.

The craft endured 31 months in deep-space hibernation on the most distant leg of its journey, before waking up in January 2014 and finally arriving at the comet in August 2014.

After becoming the first spacecraft to orbit a comet, and the first to deploy a lander, Philae, in November 2014, Rosetta continued to monitor the comet’s evolution during their closest approach to the Sun and beyond.

“We’ve operated in the harsh environment of the comet for 786 days, made a number of dramatic flybys close to its surface, survived several unexpected outbursts from the comet, and recovered from two spacecraft ‘safe modes’,” says operations manager Sylvain Lodiot.

“The operations in this final phase have challenged us more than ever before, but it’s a fitting end to Rosetta’s incredible adventure to follow its lander down to the comet.”

The decision to end the mission on the surface is a result of Rosetta and the comet heading out beyond the orbit of Jupiter again. Further from the Sun than Rosetta has ever journeyed before, there would be little power to operate the craft.

Mission operators were also faced with an imminent month-long period when the Sun is close to the line-of-sight between Earth and Rosetta, meaning communications with the craft would have become increasingly more difficult.

“With the decision to take Rosetta down to the comet’s surface, we boosted the scientific return of the mission through this last, once-in-a-lifetime operation,” says mission manager Patrick Martin.

“It’s a bittersweet ending, but in the end the mechanics of the Solar System were simply against us: Rosetta’s destiny was set a long time ago. But its superb achievements will now remain for posterity and be used by the next generation of young scientists and engineers around the world.”

While the operational side of the mission has finished today, the science analysis will continue for many years to come.

Many surprising discoveries have already been made during the mission, not least the curious shape of the comet that became apparent during Rosetta’s approach in July and August 2014. Scientists now believe that the comet’s two lobes formed independently, joining in a low-speed collision in the early days of the Solar System.

Long-term monitoring has also shown just how important the comet’s shape is in influencing its seasons, in moving dust across its surface, and in explaining the variations measured in the density and composition of the coma, the comet’s ‘atmosphere’.

Some of the most unexpected and important results are linked to the gases streaming from the comet’s nucleus, including the discovery of molecular oxygen and nitrogen, and water with a different ‘flavour’ to that in Earth’s oceans.

Together, these results point to the comet being born in a very cold region of the protoplanetary nebula when the Solar System was still forming more than 4.5 billion years ago.

While it seems that the impact of comets like Rosetta’s may not have delivered as much of Earth’s water as previously thought, another much anticipated question was whether they could have brought ingredients regarded as crucial for the origin of life.

Rosetta did not disappoint, detecting the amino acid glycine, which is commonly found in proteins, and phosphorus, a key component of DNA and cell membranes. Numerous organic compounds were also detected ­by Rosetta from orbit, and also by Philae in situ on the surface.

Overall, the results delivered by Rosetta so far paint comets as ancient leftovers of early Solar System formation, rather than fragments of collisions between larger bodies later on, giving an unparalleled insight into what the building blocks of the planets may have looked like 4.6 billion years ago.

“Just as the Rosetta Stone after which this mission was named was pivotal in understanding ancient language and history, the vast treasure trove of Rosetta spacecraft data is changing our view on how comets and the Solar System formed,” says project scientist Matt Taylor.

“Inevitably, we now have new mysteries to solve. The comet hasn’t given up all of its secrets yet, and there are sure to be many surprises hidden in this incredible archive. So don’t go anywhere yet – we’re only just beginning.”

Source: European Space Agency

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Rosetta's final image of 67P/Churyumov–Gerasimenko before the spacecraft crash-landed onto the comet's surface...on September 30, 2016.
ESA / Rosetta / MPS for OSIRIS Team MPS / UPD / LAM / IAA / SSO / INTA / UPM / DASP / IDA