NASA releases arbitrary deadline to revive Mars Rover

The dust storm on Mars is over, but Opportunity has yet to wake up. In early summer, the rover was forced to hibernate by an extreme Martian dust storm that darkened the red planet's sky to a level we have never seen before. Most of the time, Mars has a tau – a scientific term that denotes the opacity of the Martian atmosphere – from 1 to 2. At the biggest dust storm we've ever seen, the tau was about 6. This time, the tau of the massive storm has reached 10.8 – and Opportunity is powered by solar energy.

NASA has now announced that the window of opportunity is remarkably short. In 45 days, if NASA has not heard from the mobile or has not been able to contact it, it will end the mission. And this time interval has a lot of engineers and scientists upset, given the working mechanism of dust and dust storms on Mars.

In the 14 years since its launch on Mars, Opportunity's power levels have fluctuated wildly for two main reasons. First, the solar energy dependence of the rover means that the amount of energy it receives depends on the position of Mars relative to the Sun. The distance of Mars from the Sun varies from 1.38 AU to 1.67 AU, and the long Martian winters generally provide much less power. Secondly, the same wind that occasionally covers the dust rover has also been known to clean and polish solar panels, sometimes bringing them back to almost total power. The graph below shows how Opportunity's power levels have fluctuated in 2017-18.

Image by Wikipedia

On June 3, Opportunity produced 468 Wh of energy. On June 6th, this figure had fallen to 133 Wh as the dust storm approached. On June 10, only 22 Wh of energy was available. Whether the rover wakes up will depend in part on the clarity of the solar panels. And the members of the team working on Opportunity point out that NASA's 45-day limit seems to have come from nowhere. When Spirit was killed in 2010, NASA spent 10 months actively trying to communicate with the mobile and five months passively listening to his communication. The 45-day clock will not start until the tau above the mobile is confirmed at 1.5 or less, but L & # 39; Atlantic The details, many members of the NASA Opportunity team are unhappy with the idea of ​​abandoning the project without spilling all the stones and doing everything to make the robot operational.

You're joking. 45 days after a Tau of 1.5. This can not be based on a real analysis of the situation.

Someone in the MER project, the Mars program or elsewhere must try to kill the mission for non-technical reasons.#SaveOppy #WakeUpOppyhttps://t.co/Zill7w0Gmx

– Mike Seibert (@mikeseibert) August 30, 2018

There are two ways to look at this question. On the one hand, maintaining an active mission around Opportunity costs money and NASA does not have a ton. You could argue that after 14 years, there are simply different places to allocate those dollars. The other argument is that it's incredibly dear to put a new rover on Mars. It is best to extract each scientific observation from an available instrument because the new instruments are an extremely rare event. There is also no guarantee that any attempt to place a new mobile on Mars does not explode on the launch pad or fails en route. Which of these arguments is right will depend on where NASA should prioritize its spending, but the cost of taking over Opportunity represents a fraction of the cost of replacing the mobile. You can make a convincing case for a more aggressive attempt at contact for these reasons alone.

One of the reasons engineers are calling for a longer active listening session is that the mobile clock may have failed and may not know when to call home for instructions. When NASA listens actively, it means that it sends a periodic communication pulse to order the mobile to call home, if it happens to be alive and its radio is functional. Passive monitoring simply means that you listen to the frequencies that the router can use (apparently, these can drift) and hope that it will try to contact you.

Hope that Opportunity will wake up alone, avoiding the argument. For now, NASA's plan to get by in 45 days does not win any organizer.

Now read: NASA loses contact with opportunity as Storm unleashes, opportunities remain silent as the dust storm disappears, opportunities have now worked for 5,000 Martian days