Curiosity, NASA’s Mars Science Laboratory (MSL), has been wrapping things up in the “Pahrump Hills” region at the base of “Mount Sharp”, the mountain-sized mound of deposited material occupying the centre of Gale Crater.
For the last several months, the rover has been engaged on what geologists on Earth call a “walkabout”, zigzagging back and forth across the area, looking for targets of interest for follow-up investigations, and allow the science team to better understand the geology and form of the region.
This method of activity is a change from how Curiosity has largely operated to date, which has seen the rover primarily move from point-to-point along its route, only re-visiting sites as a part of its onward movement towards the goal of reaching and climbing “Mount Sharp” (such as when travelling into, and then back out of the “Glenelg” and “Yellowknife Bay” regions Curiosity first explored in 2012 / 2013).
In this respect, and as Aileen Yingst, the Deputy Principal Investigator with the Mars Hand Lens Imager (MAHLI) on the rover, describes, Curiosity has been demonstrating just how much of an avatar it is for the science team, allowing them to careful investigate, examine and catalogue “Pahrump Hills” in a rich, practical way using the very human technique of the “walkabout”, which will serve the mission well as the ascent up “Mount Sharp” continues.
Most recently, and since collecting samples from “Mojave 2″, the area of rock displaying interesting crystalline elements within it, Curiosity has been looking at an area geologists dubbed “pink cliffs”, which shows further signs of the crystalline structures, and might be a candidate for further investigation. If so, it will be the last stopping point in “Pahrump Hills” before Curiosity continues its climb up “Mount Sharp”.
Oppy Reaches 11
January 25th, 2015 saw NASA’s Mars Exploration Rover, Opportunity, reach it’s eleventh anniversary on Mars. The rover, one of two MER vehicles, arrived on Mars at January 25th, 2004 (Universal Time), ready to start a mission initially planned to last just 90 days.
Since then, and up to its anniversary, “Oppy” has travelled a distance of some 41.7 kilometres (25.9 miles). While this doesn’t sound that much (and in truth, a human science team could have travelled that far in just a few days, including time for any science carried out along the way), remember that “Oppy’s” forward speed is measured in centimetres per hour.
As one of two solar-powered MER rovers (the second, Spirit having finally succumbed to the hostile environment on Mars around March 215th, 2011), Opportunity has carried out an incredible amount of work, and greatly contributed to our understanding of the planet, returning compelling evidence about wet environments on ancient Mars.
The rover marked its anniversary by reaching the summit of “Cape Tribulation”, an uprising close to the rim of 20 kilometre (13.7 mile) wide Endeavour Crater, which the rover has been gradually circumnavigating. This involved a change in elevation for “Oppy” of about 135 metres (440 feet), and afforded it a panoramic view of the crater and the land around it, presenting a unique opportunity for geological observations of the crater and its rim.
A New Mars Mystery
That night, too, there was another jetting out of gas from the distant planet. I saw it … That night another invisible missile started on its way to the earth from Mars, just a second or so under twenty-four hours after the first one.
– The narrator, H.G. Wells’ The War of the Worlds
Okay, so it’s unlikely to be the sign of an impending invasion of Martians possibly ticked-of at the way we’re cluttering-up their planet with our probes and landers and rovers, but recent events high in the atmosphere of Mars have given rise to some excitement.
The images, originally capture in 2012, show huge plumes rising some 250 kilometres (156 miles) into the most tenuous reaches of Mars’ thin atmosphere.
The plumes occurred on two separate occasions in March and April 2012, and were spotted by amateur astronomers. Each time, they developed with relative rapidity, rising upwards and outwards to cover areas of some 1000 x 500 kilometres (625 x 312.5 miles) in a period of around 10 hours before remaining visible for up to 10 days at a time, their structure and form changing on a daily basis.
Unfortunately, neither event was seen from orbit about Mars, occurring so high on the planet’s limb as to be effectively out-of-sight for the NASA and ESA orbital vehicles, and by the time word had spread sufficiently about the observations, the events were largely over.
However, investigations into images of the planet taken by the Hubble Space Telescope in orbit around the Earth have revealed similar plumes being imaged in the past. However, with the exception of an image captured in 1997, none have been anywhere near as high or dramatic as the 2012 events.
So what might have caused this plumes to occur? The answer to that question is uncertain.
“At about 250 km, the division between the atmosphere and outer space is very thin, so the reported plumes are extremely unexpected,” says Agustin Sanchez-Lavega of the Universidad del País Vasco in Spain, lead author of the paper reporting the observations and subsequent study in the science journal Nature. “One idea we’ve discussed is that the features are caused by a reflective cloud of water-ice, carbon dioxide-ice, or dust particles, but this would require exceptional deviations from standard atmospheric circulation models to explain cloud formations at such high altitudes.”
What might be a more likely explanation is that the plumes could be a form of auroral emission, somewhat akin to those we see here on Earth and the result of interactions between solar particles and the Earth’s magnetic field. While Mars has an almost negligible magnetic field, there have been large anomalies detected it the planet’s crustal magnetic field, one of which is directly under the locations where the 2012 plumes occurred, so the possibility of some form of solar / aero-magnetic activity occurring cannot be discounted.
NASA’s Europa Mission Secures Further Funding
Europa is one of the four large moons orbiting Jupiter and which were first observed by Galileo in 1610, and which are still known as the Galilean moons to this day.
Slightly smaller than our own Moon, Europa is unique in a number of ways. Firstly, it is entirely covered in water ice, and has a very tenuous oxygen-rich atmosphere. Secondly, while criss-crossed with cracks and crevasses, the ice is almost uniformly smooth, leading to speculation that it is sitting over a deep liquid water ocean surrounding Europa’s solid core, and that tidal flexing is generating heat deep within Europa, which keeps the ocean under the ice in motion, thus given rise to the cracks and crevasses as the ice is is subjected to the stresses of that motion.
Most intriguingly, it is believed that this tidal flexing may also give rise to deep water volcanism, which could result in mineral-rich “hotspots” on the ocean floor where life might arise (just as it does in regions of deep-sea volcanism here on Earth), making Europa a considerable target for detailed scientific examination.
The idea that the ocean under the ice may be rich in chemicals and minerals suitable for life gained a boost at the end of 2013, when NASA was able to confirm that the brown discolouration seen over much of Europa’s surface is caused by clay-like minerals, notably phyllosilicates, which can be associated with organics. These, together with the moon’s very tenuous, oxygen-rich atmosphere, are likely being outgassed from the ocean through the cracks in the ice.
Given this, it should come as no surprise that Europa is a place scientists want to explore in greater detail. Currently, the European Space Agency is currently planning a mission, called JUICE (for JUpiter ICy Moon Explorer), which will do this in the 2030s, as well as study Jupiter’s other icy moons, Ganymede and Callisto. NASA’s own plans were also given a further boost in February, when the White House announced that of the US $18.5 billion awarded to the US space agency’s 2016 budget, $30 million is to be specifically targeted at planning for a Europa mission.
The most likely candidate for such a mission would be Europa Clipper, a probe which would be placed in orbit around Jupiter such that over 3.5 years, it would be able to make up to 48 fly-bys of the Moon at a range of altitudes and conduct intensive studies aimed at further determining Europa’s potential habitability and to conduct survey missions for a possible follow-up lander mission.
While NASA’s 2016 budget (which commences on October 1st, 2015), has yet to be approved by Congress, it seems like the Europa mission budget for 2016 will gain approval; in 2013, Congress approved US $75 million being awarded to preliminary mission studies, and in 2014 increased US $15 million awarded for further studies to a total of US $100 million.
SpaceX Leases Launch Complexes
As I noted in my last Space update, SpaceX, the private enterprise space company is working to develop a reusable launcher system, which includes a first stage of the Falcon rockets which is capable of flying back to a safe landing after use in a launch. While the development of this capability is still very much under-way, SpaceX recently demonstrated their confidence in reaching their goal.
In January, the US Air Force confirmed that the company has leased Space Launch Complex 4W (SLC-4W) at the USAF’s space launch centre at Vandenberg AFB, California. SLC-4W sits alongside the facilities SpaceX already use for their Pacific coast launches (SLC-4E), and work has apparently already started in converted SLC-4W into a landing facility for returning Falcon rocket stages.
The Vandenberg confirmation was followed In February by a US Air Force announcement that SpaceX had leased Launch Complex 13 at the Canaveral Air Force Station in Florida, and that the arrangement includes an agreement to convert it into a landing site for Falcon rocket stages launched from Florida’s Space Coast.
ESA Focuses ATV Attention on Orion
After the recent successful flight of their IXV vehicle, ESA has now said “farewell” to the last of their Automated Transfer Vehicles (ATVs), as the Georges Lemaître departed the International Space Station on Valentine’s Day 2015, before burning-up in the Earth’s atmosphere the following day.
With five missions spread across seven years, the ATV has been one of the most advanced automated space vehicles operated in space thus far. Capable of hauling up to 8 tonnes of supplies to the space station at a time, and fully able to refuel the station’s attitude control thruster systems, the ATV has proven itself an invaluable workhorse since 2008, but its legacy doesn’t lay with the final flight.
While no further resupply ATVs are planned, the technology used to develop the vehicle will be carried forward and enhanced as ESA now shifts the programme’s focus entirely towards building the Service Module element of NASA’s upcoming Multi-Purpose Crewed Vehicle, Orion, which sits at the focal-point of that agency’s deep-space crewed space flight hopes.
The Orion capsule itself was successfully flown in an uncrewed test mission in December 2014.
If all goes according to plan, the next flight – in 2018 – will see the Orion capsule mated to the ATV derived Service Module in an uncrewed flight around the Moon, ahead of initial crewed missions, slated to start in 2021.
The Service Module is critical to the Orion System, in that it will provide the capsule with its life support, electrical and environmental power, and provide propulsion.
Unless otherwise stated, all images and video courtesy of NASA / JPL.