Space Sunday: probing inside other worlds

CuriosityIn December 2014, I wrote about the Curiosity science team reporting they had detected odd “spikes” in methane levels in the Martian atmosphere as a result of analyses undertaken by the SAM (Sample Analysis at Mars) mini laboratory within the Mars rover.

Methane had first been definitively detected on Mars by the 2008 Phoenix Lander, although its presence had long been suspected and indicated. However, Curiosity’s discovery of two sudden sharp increases in the normal levels of traceable methane to some 7 part per billion – a ten time increase of the expected levels – suggested it had perhaps happened across some localised methane-producing source, possibly of organic nature (notes that “organic” in this case doesn’t actually mean “living things”).

However, the results have recently had some doubt cast upon them, and from within NASA itself. Kevin Zahnle, a scientist at NASA’s Ames Research Centre in California has been studying the data and suggested that the methane spikes could have come from a very localised source – a leaf of Earthly air previously trapped somewhere in the rover’s insides.

Could a small pocket of air carried from Earth have leaked into one of the spectrometers aboard Curiosity's SAM instrument and caused spurious  methane counts?
Could a small pocket of air carried from Earth have leaked into one of the spectrometers aboard Curiosity’s SAM instrument and caused spurious methane counts? Image: NASA / JPL

Depsite rigorous decontamination processes prior to launch, is is possible for air and gas pockets to get trapped inside a robot vehicle. This is actually what happened at the start of Curiosity’s sojourn on Mars: during its initial analysis of the atmosphere around it, the rover also detected abnormally high levels of methane, only for it to be tracked back to tiny amount of air carried aboard the rover leaking into the spectrometer carrying out the methane measurements. Zahnle suggests that a similar leak cannot yet be ruled-out as the cause of the 2013 and 2014 spikes.

Members of the Curiosity science team argue that as a result of the initial leak, they have taken every caution to prevent being misled again, and are confident that only the most exceptional of circumstances could result in SAM’s findings being the result of methane “trapped” somewhere inside the rover only get released well over a year after its arrival on Mars. However, they also admit that the potential for such a situation cannot be entirely ruled-out.

One of the arguments for the spikes being the result of contamination from within the rover is that similar readings haven’t since been recorded. A counter argument to this is that the levels SAM recorded could be the result of a yet-to-be-understood seasonal phenomena. To this end, the rover is going to be sniffing the air around it very carefully during late 2015 / early 2016 to see if it can detect any similar spikes.

Insight (in) to Mars

An artist's impression of InSight on Mars
An artist’s impression of InSight on Mars.  Image: NASA / JPL

NASA’s next mission to Mars is scheduled to launch a March 2016. In keeping with the agency’s (roughly) alternating approach to surface mission to the planet, which switch between landers craft and rovers, the InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) mission is a lander mission.

As the full version of its name suggests, InSight is intended to probe the deep interior of Mars. In doing so, it is hoped the mission will not only add to our understanding of Mars, but also our understanding of the processes that shaped the rocky planets of the inner solar system (including Earth) more than four billion years ago.

Following its launch, InSight will cruise to Mars in a flight of roughly 6 months, landing on the surface in September of that year. After a check-out and calibration period, the science mission will commence in October 2016, with the overall surface mission expected to last 700 Sols (roughly 720 Earth days).

The solar arrays on NASA's InSight lander are deployed in this test inside a clean room at Lockheed Martin Space Systems, Denver. This configuration is how the spacecraft will look on the surface of Mars.Image Credit: NASA/JPL-Caltech/Lockheed Martin
The solar arrays on NASA’s InSight lander are deployed in this test inside a clean room at Lockheed Martin Space Systems, Denver. This configuration is how the spacecraft will look on the surface of Mars.Image: NASA / JPL / Lockheed Martin

The reason Mars is being used in this way, rather than scientists simply studying the Earth to better understand the processes involved in shaping the rocky worlds of the solar system is that Mars are far less geologically active than Earth, it retains a more complete record of its history in its own basic planetary building blocks: its core, mantle and crust than does Earth.

The Lander for the mission is based on the successful design of the 2008 Phoenix mission, and will include technology and instruments that will be deployed onto the surface of Mars, including the HP3 “mole” which will burrow its way deep below the surface (see the artist’s impression under the headline to this piece) in an attempt to more accurately measure the amount of heat flowing outwards from the planet’s core.

As a part of preparations for the mission launch, the end of May saw InSight commence seven months of extensive testing which will involve it experiencing extreme temperatures, vacuum-space conditions with near-zero air pressure, and simulated Martian surface conditions, in order to assess the vehicle’s various elements and systems and ensure as far as possible that they are ready for the rigours of space flight and operating in the Martian environment. Also during the tests, the lander will be exposed to the stresses of a simulated launch and undergo extensive electrical testing to ensure the robustness of its electronics.

Europa Clipper Mission Update

In  February I wrote about NASA’s Europa Clipper mission, which is intended to explore one of the most enigmatic places in the solar system – Jupiter’s icy moon Europa. Planning for such a mission has been underway for some time, and in 2013 and 2014, the US Congress increased the amount NASA was able to spend on such planning, and it was believed this would continue through the 2016 budget (which commences in October 2015) as well.

In late May NASA gave a further boost to the mission by announcing Europa Clipper’s science payload. In all, nine instruments will be carried aboard the vehicle, which will be launched some time in the early-to-mid 2020s and will orbit Jupiter, allowing it to make multiple fly-bys of Europa over a period of 3 – 3.5 years.

The primary aim of these instruments will be to image and probe Europa’s water ice crust to try to shed light on the satellite’s surface composition and the nature of its salty subsurface sea. The later is thought to extend down as far as Europa’s core, and is thought to be kept liquid by tidal flexing. This, it is believed, might also give rise to deep-water volcanism and thermal venting on the ocean floor, creating chemical and mineral rich “hotspots” where basic life could conceivably arise and thrive for as long as the hotspots are active – as is the case here on Earth, as shown in the video below.

NASA Issues First Order for US Commercial Crew Launch to ISS

NASA has placed its first order for a US commercial launch vehicle to lift a crew to the International Space Station.

Following the retirement of the space shuttle, NASA opted to hand over the task of carrying crews to the ISS from US soil and returning them to the Earth to the private sector, leaving itself free to focus on deep-space human missions such as to cislunar space and, in the 2030s, to Mars.

Two companies eventually secured contracts to build the craft to fly crews to / from the space station: SpaceX and NASA’s long-term partner Boeing; a decision which itself was controversial when made at the end of 2014.

Boeing's CT-100 launch system - each vehicle is designed to make up to 10 flights
Boeing’s CST-100 launch system – each vehicle is designed to make up to 10 flights

At that time, there were four of potential candidates in the running for a NASA contract, with Boeing seemingly lagging behind, despite gaining the lion’s share of funding to that point. As a result, Sierra Nevada Corporation, another company in the running, lodged an official protest with the US Government over the selection of Boeing, citing the fact that their own vehicle, Dream Chaser, was further along in development and represented a lower overall cost to NASA. However, the complaint was overturned, allowing Boeing and SpaceX to proceed in developing their respective capsule vehicles.

SpaceX has been very much in the public eye with their Dragon 2 crewed vehicle, which on May 6th, 2015, underwent a public and very successful test of its launch abort system which is designed to push the crewed vehicle free of its launch rocket in the event of a malfunction with the latter. Boeing, meanwhile has been more circumspect in the development of their CST-100 capsule vehicle, so the news given on May 29th that they had received the first confirmed order to launch a crew to the ISS, while not unexpected in the scheme of things, was still a surprise; many had thought SpaceX would get the first confirmed order – they are now expected to receive theirs later in the year.

A Boeing CST-100 test article undergoing drop and floatation tests in 2014
A Boeing CST-100 test article undergoing drop and floatation tests in 2014. Image: Boeing Aerospace

However, the order given to Boeing doesn’t necessarily mean they will be the first to launch a crew to the ISS, which are due to start in early 2017; that honour still has to be decided, but it does now mean that they are likely to make a crewed launch to the ISS before the end of 2017.

Currently, crewed launches to the ISS are limited to 3 crew at a time via the Russian Soyuz space vehicle. But two recent failures with Russian launch systems (neither of which resulted in loss of life) has meant that launch schedules for both crewed launches out of Russia and uncrewed Progress resupply missions have been subjected to delay – making NASA more keen to have the two private sector vehicles, with their large (6 person) capacities, keep to schedule.

LightSail Update

In my last Space Sunday report, I wrote about LightSail, a publicly-funded attempt to prove the effectiveness of using solar sails as a means of propulsion.

The first phase of the project is currently in orbit about the Earth, comprising a little CubeSat, the size of a loaf of bread, into which is packed a 32 square metre (344 square feet) solar sail. The mission is intended to test the means of deploying the sail, which is just 4.5 microns thick, ahead of a planned 2016 test flight which will see a similar sail deployed and used as a means of propulsion, “sailing” the solar wind of charged particles flowing outward from the sun.

An artist's impression of a Lightsail CubeSat with its sail fully deployed
An artist’s impression of a Lightsail CubeSat with its sail fully deployed. Image: The Planetary Society

However, following launch, a software bug caused the tiny satellite’s memory buffer to overload, “freezing” all operations and preventing communications with ground control. Unable to order the CubeSat to reboot itself – a process that would have cleared the buffer and allowed the upload of a software patch to fix the problem – the mission team were left hoping that a fast-moving charged particle might strike the electronics components in the satellite in just the right way, causing LightSail 1 to reboot itself.

While the odds of this happening might seem – and pardon the term – astronomical, it has in fact happened in the past to spacecraft. And it is also precisely what appears to have happened to LightSail 1. At 21:21 UTC on Saturday, May 30th, after almost a week of silence, the little satellite started communicating again. As one commentator from the Planetary Society put it, “A little nuclei, maybe from a supernova, just travelled hundreds of millions of years to help us out and restart the computer on LightSail 1”.

The Planetary Society announced the news via a picture Tweet:

The Planetary Society announces Lightsail 1 back in communication, May 30th, 2015
The Planetary Society announces Lightsail 1 back in communication, May 30th, 2015

The priority now is to upload a software patch to prevent the glitch recurring, and then it is likely the craft will be checked out and revised plans drawn-up to deploy the sail. I’ll hopefully have a follow-up next week.