MARS: S putovanja rovera OPPORTUNITY

sol 4746 ....zanimljiva odluka.

OPPORTUNITY UPDATE:  Walkabout Above 'Perseverance Valley'
- sols 4746 to 4752, May 31, 2016 - June 6, 2017:
Opportunity is at the top of "Perseverance Valley" on the rim of Endeavour Crater. The plan before proceeding down the valley is to perform a walk-about survey above the valley.

To start the walkabout, on Sol 4746 (May 31, 2017) Opportunity drove about 82 feet (24.9 meters) mostly south toward a chosen waypoint. Images for extensive panoramas were collected with the Navigation Camera (Navcam) and the Panoramic Camera (Pancam). On Sol 4748 (June 2, 2017), the rover took advantage of an opportunity to address some long-standing liens by imaging the grind bit of the Rock Abrasion Tool (RAT) and by collecting some Microscopic Imager (MI) sky flats, both of which require extensive robotic arm movement. On Sol 4750 (June 4, 2017), the plan was to perform a short, tight backward arc, but the left-front steering actuator stalled. With the left-front wheel steered to more than 30 degrees from straight, the focus of the team is first to assess whether this stall was a terrain related phenomenon. So, on Sol 4752 (June 6, 2017), the rover arced back without steering the left-front wheel and imaged the location of the steering stall. Although there is evidence to suggest a terrain effect, it is not conclusive. The next step will be a careful attempt to straighten the left-front wheel. The plan on Sol 4754 (June 8, 2017) is to gently turn the wheel straight.

As of Sol 4752 (June 6, 2017), the solar array energy production is 362 watt-hours with an atmospheric opacity (Tau) of 0.788 and a solar array dust factor of 0.530.

Total odometry as of Sol 4752 is 27.87 miles (44.86 kilometers).

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Oboje boldano je veoma loše...Ne čudi nakon svega što je vozilo prošlo.

What created this unusual hole in Mars? Actually, there are numerous holes pictured in this Swiss cheese-like landscape, with all-but-one of them showing a dusty, dark, Martian terrain beneath evaporating, light, carbon-dioxide ice. The most unusual hole is on the upper right, spans about 100-meters, and seems to punch through to a lower level. Why this hole exists and why it is surrounded by a circular crater remains a topic of speculation, although a leading hypothesis is that it was created by a meteor impact. Holes such as this are of particular interest because they might be portals to lower levels that extend into expansive underground caves. If so, these naturally-occurring tunnels are relatively protected from the harsh surface of Mars, making them relatively good candidates to contain Martian life. These pits are therefore prime targets for possible future spacecraft, robots, and even human interplanetary explorers.
Image Credit: NASA, MRO, HiRISE, JPL, U. Arizona

kic wrote:


What created this unusual hole in Mars? Actually, there are numerous holes pictured in this Swiss cheese-like landscape, with all-but-one of them showing a dusty, dark, Martian terrain beneath evaporating, light, carbon-dioxide ice. The most unusual hole is on the upper right, spans about 100-meters, and seems to punch through to a lower level. Why this hole exists and why it is surrounded by a circular crater remains a topic of speculation, although a leading hypothesis is that it was created by a meteor impact. Holes such as this are of particular interest because they might be portals to lower levels that extend into expansive underground caves. If so, these naturally-occurring tunnels are relatively protected from the harsh surface of Mars, making them relatively good candidates to contain Martian life. These pits are therefore prime targets for possible future spacecraft, robots, and even human interplanetary explorers.
Image Credit: NASA, MRO, HiRISE, JPL, U. Arizona

Bilo bi veoma jednostavno objasniti ako ne bi onog uzorka bilo i u krateru.
Ono što bi za sada ja mogao reći je da je ovaj bijeli materijal bio sastavni dio tijela koje je udarilo u tlo Marsa.
Druga mogućnost je da je rupa ostatak vrela iz kojeg je isticalo ovo bijelo, šta vidimo...carbon-dioxide ice, ili šta već.

sol 4766...nakon velikih problema s kotačem prevozio 6 m.
Pitanje je koliko dugo će ovo funkcionirati.Ako su "četkice" na motoru u pitanju onda nema nade...

U ekipi koji upravljaju roverom je bilo razmišljanja da  bi problemi sa kotačem mogli značiti i "početak kraja".
Na svu sreću uspjelo se stvari izanalizirati i povuci-potegni i evo sad opet tradi.

Glavni RoverDriver, Paolo Belutta, na forumu UMSF, kaže uz ostalo i ov:

" The wear and tear on the brushes is proportional to each actuator use. If you take the current rover odometer, divide by one wheel circumference and multiply by 1500 (the gear ratio) you get a decent number (100 million revs) which is not too shabby but not too out of specs...." 
Pošto sam iz ovog područja u struci, mogu samo reći da znamo kako se materijali ponašaju kod 1 do najviše 5 milijuna ponavljanja.
Kod 100 milijuna nitko ne zna...

Putanja kretanja vozila u naslednjih par tjedana, kad nastupa solarna konjukcija i relativno mirovanje, dok ta ne prođe. 

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Publish Date: 
Wednesday, June 21, 2017 - 2:30pm
Opportunity is doing a geologic walkabout at the entrance to Perseverance Valley. There is an odd trough-like feature leading into the entrance of the valley and the natural suspicion is that it could be the water course that supplied the valley. We would like to get a look at the geologyto see if that is what formed the trough. Also, once Opportunity starts descending the valley, it will not be driving back up slope. We fully intend to exit out the bottom of the valley inside Endeavour crater. So any questions we have about bwhat went into the valley to form it, we need to ask and answer now.
Mean while, there is the mater of solar conjunction coming up in  a few weeks. Solar conjunction is a period of two to three weeks during which Mars is behind the sun or nearly so, and communications wibetween Earth and Mars is a bit sketchy. We have decided to wait outside the valley until solar conjunction is over. Then Opportunity will begin the descent in ernest. That will be around the beginning of August.

sol 4769

sol 4772

sol 4772  ...ispravak gornje rute!

sol 4775

sol 4779 ...ovdje će najvjerojatnije sačekat da konjukcija prođe.

sol 4781

Predpostavljam da će se spustiti do ovog kraterčića ispod i tu se zadržati dok se konjukcija ne završi.

sol 4782    ...baš kako sam i predpostavio.