Rosetta will crash into the Ma’at region of Comet 67P/Churyumov–Gerasimenko. The yellow ellipse marks an approximate outline of the 700- × 500-meter (700- x 500-yard) target area. Image via ESA.
The Rosetta spacecraft – which has been orbiting Comet 67P/Churyumov-Gerasimenko’s since August, 2014 – is scheduled to complete its mission in a controlled descent to the comet’s surface on September 30, 2016. End of mission confirmation is predicted to be within 20 minutes of 11:20 UTC (7:20 a.m. ET) on that day. Translate to your time zone. Details of how, when and where to follow the key moments online can be found here.
The image above shows the target point, which is adjacent to an active pit that the mission team has informally named Deir el-Medina. In describing this image, ESA said:
The target area is home to several active pits measuring over 100 meters across and 60 meters deep [about 100 yards wide and 60 yards deep], from which a number of the comet’s dust jets originate. Some of the pit walls also exhibit intriguing meter-sized lumpy structures called ‘goosebumps’, which could be the signatures of early cometesimals [i.e, the building blocks of comets] that agglomerated to create the comet in the early phases of solar system formation.
Rosetta’s final descent may afford detailed close-up views of these features.
On September 29, there will be dedicated talks celebrating the scientific highlights of the mission. Tune in to them via:
On September 30, there will be a short transmission confirming Rosetta’s impact on the comet. It will be streamed via the three links just above.
More Rosetta end-of-mission activities here
View larger. | Compilation of the brightest outbursts seen at Comet 67P/Churyumov–Gerasimenko by Rosetta spacecraft between July and September 2015, via ESA.
Since August 9, ESA said, Rosetta has been flying elliptical orbits that bring it progressively closer to the comet. Sylvain Lodiot, ESA’s spacecraft operations manager, said in a September 9 statement:
Although we’ve been flying Rosetta around the comet for two years now, keeping it operating safely for the final weeks of the mission in the unpredictable environment of this comet and so far from the sun and Earth, will be our biggest challenge yet.
We are already feeling the difference in gravitational pull of the comet as we fly closer and closer: it is increasing the spacecraft’s orbital period, which has to be corrected by small manoeuvers.
But this is why we have these flyovers, stepping down in small increments to be robust against these issues when we make the final approach.
View larger. | See the red arced line, top of image? It’s a depiction of the Rosetta spacecraft in early 2016, leaving the inner solar system. Image via Where is Rosetta?
It’s sad to see this wonderful mission end, but exciting to see it go out with such a flourish. Who can forget the thrill two years ago, when Rosetta arrived at its comet? But ending the mission now is logical for several reasons.
For one thing, the comet and spacecraft are getting ever-farther from the sun. The craft is heading out towards the orbit of Jupiter and consequently it’s receiving less sunlight. The solar power needed to operate the craft and its instruments is waning, and there’s been a reduction in the bandwidth available to downlink scientific data back to the European Space Agency (ESA), which spearheaded the mission.
Plus … Rosetta and her instruments are aging. The mission launched on March 2, 2004, aboard an Ariane 5 rocket. On its way toward a rendezvous with its comet, Rosetta made four slingshot flybys to boost its speed via gravitational assist — one around Mars and three around Earth. Now Rosetta has been in the harsh environment of space for over 12 years, the last two of which were in the dusty environment of Comet 67P/Churyumov-Gerasimenko in the most volatile part of its orbit, as it swung in near the sun before and after its perihelion on August 13, 2015.
In addition, beginning around October 1, 2016, if the mission were to continue Rosetta’s operators would be facing reduced communications due to a conjunction of the comet and spacecraft. That is, the comet is now edging into the sun’s glare and will soon be behind the sun as seen from Earth. ESA said this is another contributing factor to concluding the mission in late September.
By September 30, 2016, Rosetta will be about 356 million miles (573 million km) from the sun and 447 million miles (720 million km) from Earth.
The one-way signal travel time will be about 40 minutes.
Before the Rosetta spacecraft mission, who knew comets looked like this? Four-image Rosetta NAVCAM mosaic, using images taken on September 19, 2014 when the spacecraft was 17.8 miles (28.6 km) from Comet 67P/Churyumov-Gerasimenko, via ESA.
View larger. | Rosetta’s location on September 30, 2016, the day of its planned controlled descent to surface of the comet it’s shadowed since August, 2014. The descent marks the end of the Rosetta mission. Image via ESA.
ESA said Rosetta’s final hours will be action-packed as the craft descends toward its comet:
[The descent] will enable Rosetta to make many once-in-a-lifetime measurements, including very-high-resolution imaging, boosting Rosetta’s science return with precious close-up data achievable only through such a unique conclusion.
Communications will cease, however, once the orbiter reaches the surface, and its operations will then end.
Farewell, Rosetta!
Read more from ESA about the grand finale of the Rosetta mission
Rosetta spacecraft ‘selfie’ with comet 67P/Churyumov–Gerasimenko, imaged Sunday, September 7, 2014. Image via ESA/Rosetta/Philae/CIVA.
Bottom line: The Rosetta comet mission will end its mission with a controlled descent to the surface of Comet 67P/Churyumov-Gerasimenko on September 30, 2016.
from EarthSky http://ift.tt/29MEGYC
Rosetta will crash into the Ma’at region of Comet 67P/Churyumov–Gerasimenko. The yellow ellipse marks an approximate outline of the 700- × 500-meter (700- x 500-yard) target area. Image via ESA.
The Rosetta spacecraft – which has been orbiting Comet 67P/Churyumov-Gerasimenko’s since August, 2014 – is scheduled to complete its mission in a controlled descent to the comet’s surface on September 30, 2016. End of mission confirmation is predicted to be within 20 minutes of 11:20 UTC (7:20 a.m. ET) on that day. Translate to your time zone. Details of how, when and where to follow the key moments online can be found here.
The image above shows the target point, which is adjacent to an active pit that the mission team has informally named Deir el-Medina. In describing this image, ESA said:
The target area is home to several active pits measuring over 100 meters across and 60 meters deep [about 100 yards wide and 60 yards deep], from which a number of the comet’s dust jets originate. Some of the pit walls also exhibit intriguing meter-sized lumpy structures called ‘goosebumps’, which could be the signatures of early cometesimals [i.e, the building blocks of comets] that agglomerated to create the comet in the early phases of solar system formation.
Rosetta’s final descent may afford detailed close-up views of these features.
On September 29, there will be dedicated talks celebrating the scientific highlights of the mission. Tune in to them via:
On September 30, there will be a short transmission confirming Rosetta’s impact on the comet. It will be streamed via the three links just above.
More Rosetta end-of-mission activities here
View larger. | Compilation of the brightest outbursts seen at Comet 67P/Churyumov–Gerasimenko by Rosetta spacecraft between July and September 2015, via ESA.
Since August 9, ESA said, Rosetta has been flying elliptical orbits that bring it progressively closer to the comet. Sylvain Lodiot, ESA’s spacecraft operations manager, said in a September 9 statement:
Although we’ve been flying Rosetta around the comet for two years now, keeping it operating safely for the final weeks of the mission in the unpredictable environment of this comet and so far from the sun and Earth, will be our biggest challenge yet.
We are already feeling the difference in gravitational pull of the comet as we fly closer and closer: it is increasing the spacecraft’s orbital period, which has to be corrected by small manoeuvers.
But this is why we have these flyovers, stepping down in small increments to be robust against these issues when we make the final approach.
View larger. | See the red arced line, top of image? It’s a depiction of the Rosetta spacecraft in early 2016, leaving the inner solar system. Image via Where is Rosetta?
It’s sad to see this wonderful mission end, but exciting to see it go out with such a flourish. Who can forget the thrill two years ago, when Rosetta arrived at its comet? But ending the mission now is logical for several reasons.
For one thing, the comet and spacecraft are getting ever-farther from the sun. The craft is heading out towards the orbit of Jupiter and consequently it’s receiving less sunlight. The solar power needed to operate the craft and its instruments is waning, and there’s been a reduction in the bandwidth available to downlink scientific data back to the European Space Agency (ESA), which spearheaded the mission.
Plus … Rosetta and her instruments are aging. The mission launched on March 2, 2004, aboard an Ariane 5 rocket. On its way toward a rendezvous with its comet, Rosetta made four slingshot flybys to boost its speed via gravitational assist — one around Mars and three around Earth. Now Rosetta has been in the harsh environment of space for over 12 years, the last two of which were in the dusty environment of Comet 67P/Churyumov-Gerasimenko in the most volatile part of its orbit, as it swung in near the sun before and after its perihelion on August 13, 2015.
In addition, beginning around October 1, 2016, if the mission were to continue Rosetta’s operators would be facing reduced communications due to a conjunction of the comet and spacecraft. That is, the comet is now edging into the sun’s glare and will soon be behind the sun as seen from Earth. ESA said this is another contributing factor to concluding the mission in late September.
By September 30, 2016, Rosetta will be about 356 million miles (573 million km) from the sun and 447 million miles (720 million km) from Earth.
The one-way signal travel time will be about 40 minutes.
Before the Rosetta spacecraft mission, who knew comets looked like this? Four-image Rosetta NAVCAM mosaic, using images taken on September 19, 2014 when the spacecraft was 17.8 miles (28.6 km) from Comet 67P/Churyumov-Gerasimenko, via ESA.
View larger. | Rosetta’s location on September 30, 2016, the day of its planned controlled descent to surface of the comet it’s shadowed since August, 2014. The descent marks the end of the Rosetta mission. Image via ESA.
ESA said Rosetta’s final hours will be action-packed as the craft descends toward its comet:
[The descent] will enable Rosetta to make many once-in-a-lifetime measurements, including very-high-resolution imaging, boosting Rosetta’s science return with precious close-up data achievable only through such a unique conclusion.
Communications will cease, however, once the orbiter reaches the surface, and its operations will then end.
Farewell, Rosetta!
Read more from ESA about the grand finale of the Rosetta mission
Rosetta spacecraft ‘selfie’ with comet 67P/Churyumov–Gerasimenko, imaged Sunday, September 7, 2014. Image via ESA/Rosetta/Philae/CIVA.
Bottom line: The Rosetta comet mission will end its mission with a controlled descent to the surface of Comet 67P/Churyumov-Gerasimenko on September 30, 2016.
from EarthSky http://ift.tt/29MEGYC
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