Liquid water lake discovered on Mars

No green men (or green women or LGBT) yet, but another scientific discovery on Mars that suggests some form of life could exist or could have existed.

Using radar the European Space Agency’s Mars Express has discovered liquid water 1.6km deep beneath the south polar region of Mars.

ESA: Mars Express Detects Liquid Water Hidden Under Planet’s South Pole

Radar data collected by ESA’s Mars Express point to a pond of liquid water buried under layers of ice and dust in the south polar region of Mars.

Evidence for the Red Planet’s watery past is prevalent across its surface in the form of vast dried-out river valley networks and gigantic outflow channels clearly imaged by orbiting spacecraft. Orbiters, together with landers and rovers exploring the martian surface, also discovered minerals that can only form in the presence of liquid water.

Early results from the 15-year old Mars Express spacecraft already found that water-ice exists at the planet’s poles and is also buried in layers interspersed with dust.

Scientists believe there could be a 20km-long lake siting under Mar's south polar ice cap.

The presence of liquid water at the base of the polar ice caps has long been suspected; after all, from studies on Earth, it is well known that the melting point of water decreases under the pressure of an overlying glacier. Moreover, the presence of salts on Mars could further reduce the melting point of water and keep the water liquid even at below-freezing temperatures.

But until now evidence from the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument, MARSIS, the first radar sounder ever to orbit another planet, remained inconclusive.

Ground-penetrating radar uses the method of sending radar pulses towards the surface and timing how long it takes for them to be reflected back to the spacecraft, and with what strength. The properties of the material that lies between influences the returned signal, which can be used to map the subsurface topography.

The radar investigation shows that south polar region of Mars is made of many layers of ice and dust down to a depth of about 1.5 km in the 200 km-wide area analysed in this study. A particularly bright radar reflection underneath the layered deposits is identified within a 20 km-wide zone.

“This subsurface anomaly on Mars has radar properties matching water or water-rich sediments,” says Roberto Orosei, principal investigator of the MARSIS experiment and lead author of the paper published in the journal Science today.

“This is just one small study area; it is an exciting prospect to think there could be more of these underground pockets of water elsewhere, yet to be discovered.”

Mars Express launched 2 June 2003 so has been in orbit for nearly fifteen years. This is an impressive mission.

If you want to have a look for yourself, Mars will be at it’s closest to Earth soon.

This year, the Red Planet will come the closest to Earth it will be for the next 17 years, making it bigger and brighter than usual.

Both Earth and Mars follow elliptical (oval-shaped) orbits around the Sun. Because Earth is closer to the Sun than Mars, it speeds along its orbit more quickly than the Red Planet. We take two trips around the Sun in about the same time it takes Mars to take one! When Earth lines up directly between Mars and the Sun, we say that Mars is in opposition.

This happens every two years or so, and this year will occur on 27 July. Mars perihelion is the point when the planet is closest to the Sun in its orbit. When this occurs within a few weeks of opposition, we get a perihelic opposition and Mars appears bigger and brighter than usual.

These perihelic oppositions are not nearly as common, happening only every 17 years or so. The last one was in 2003 and the next chance to spot Mars this close won’t be until 2035. The closest approach will occur on 31 July.

However, viewing Mars during this exciting celestial event is not just restricted to the 27th or 31st of July…you will still catch superb views for about six weeks on either side of the date of opposition. Throughout July and August, Earth and our neighbour in space will only be around 58 million kilometres apart.

https://www.stardome.org.nz/mad-about-mars/

Mars is visible (if there’s no clouds) throughout the night.It wil be one of the brightest objects in the sky, and is red tinged. There’s a massive dust storm on Mars at the moment so that helps reflect light, but will make it harder to see the lake.

See for planet viewing times: https://www.timeanddate.com/astronomy/night/new-zealand/dunedin

The Beagle had landed

In 2003 the ESA Beagle-2 spacecraft failed to confirm it had successfully landed on Mars.

Mission failure

Although the Beagle 2 craft successfully deployed from the Mars Express “mother ship”, confirmation of a successful landing was not forthcoming. Confirmation should have come on 25 December 2003, when Beagle 2 should have contacted NASA’s 2001 Mars Odysseyspacecraft that was already in orbit. In the following days, the Lovell Telescope at Jodrell Bank also failed to pick up a signal from Beagle 2.

The Beagle disappeared. It was not known if it had failed before landing or had crash landed or just failed to communicate.

But eleven years later Beagle-2 has been found safely landed on Mars but it’s solar panels and communications failed to deploy properly.

European Space Agency has announced Beagle-2 lander found on Mars:

The UK-led Beagle-2 Mars lander, which hitched a ride on ESA’s Mars Express mission and was lost on Mars since 2003, has been found in images taken by a NASA orbiter at the Red Planet.

Beagle-2 was released from its mother craft on 19 December 2003 and was due to land six days later. But nothing was heard from the lander after its scheduled touchdown, and searches by Mars Express and NASA’s Mars Odyssey mission were fruitless.

Now, over a decade later, the lander has been identified in images taken by the high-resolution camera on NASA’s Mars Reconnaissance Orbiter. The lander is seen partially deployed on the surface, showing that the entry, descent and landing sequence worked and it did indeed successfully land on Mars on Christmas Day 2003.

“We are very happy to learn that Beagle-2 touched down on Mars. The dedication of the various teams in studying high-resolution images in order to find the lander is inspiring,” says Alvaro Giménez, ESA’s Director of Science and Robotic Exploration.

“Not knowing what happened to Beagle-2 remained a nagging worry. Understanding now that Beagle-2 made it all the way down to the surface is excellent news,” adds Rudolf Schmidt, ESA’s Mars Express project manager at the time.

The high resolution images were initially searched by Michael Croon, a former member of the Mars Express operations team at ESA’s Space Operations Centre, ESOC, in Darmstadt, Germany, working in parallel with members of the Beagle-2 industrial and scientific teams.

The small size of Beagle-2 – less than 2 m across when fully deployed – meant this was a painstaking endeavour, right at the limit of the resolution of cameras in orbit around Mars.

After the identification of potential counterparts to Beagle-2 in the expected landing of Isidis Planitia, a large impact basin close the martian equator, further images were obtained and analysed by the camera team, the Beagle-2 team and NASA’s Jet Propulsion Laboratory.

The images show the lander in what appears to be a partially deployed configuration, with only one, two or at most three of the four solar panels open, and with the main parachute and what is thought to be the rear cover with its pilot/drogue parachute still attached close by.

The size, shape, colour and separation of the features are consistent with Beagle-2 and its landing components, and lie within the expected landing area at a distance of about 5 km from its centre

So the Beagle had landed.

Wikipedia: Beagle 2

Philae/comet update

It has been confirmed that after a couple of bounces Philae landed on it’s side on the comet with one of it’s three legs up in the ‘air’. It came to rest close to a cliff that prevents recharging of it’s batteries.

Now much (80%) of the science has been done the mission  is going to risk bouncing Philae into a sunnier position, with the last throw of the battery dice.

Rosetta scientists will order the dying Philae lander to “hop”. The order will be sent to Philae’s legs this evening in a bid to bounce the comet lander into a sunnier position to recharge its batteries. Read the full report here.

And:

Stuart has published his final news story of the day about the lander’s plight:

Scientists controlling the Philae lander on Comet 67P/Churyumov–Gerasimenko are preparing to make a last ditch attempt to “hop” the robotic probe into a sunnier spot on the comet’s surface.

If they fail, the lander will go into hibernation. Without sufficient sunlight on its solar panels, its mission will be over.

The lander’s legs have a built-in spring action that can be commanded to fire. These commands will be uploaded tonight during an expected communications window that opens at around 21:00 GMT. There is no guarantee of success. 

Read the rest of his story here.

The Guardian have a summary:

  • Simulations suggest battery power will last long enough for tonight’s data transmission from Philae between 21:00 and 23:00 GMT.
  • Esa is considering whether to spin Philae’s flywheel (designed to keep the craft upright during flight) to ‘bounce’ the lander into a new position where its solar arrays will get more sunlight to recharge its batteries.
  • 80-90% of the intended science will have been carried out, but there’s some doubt over whether all the data will be uploaded before the lander loses all power.
  • All the lander’s instruments are working well. MUPUS and APXS instruments were used last night and the drill was activated. Esa will know this evening whether drill samples have been taken successfully. There will be more CONSERT radar data tonight, which will be used to try to locate Philae.
  • As the comet reaches its closest approach to the sun next year, there may be enough power from Philae’s solar panels to wake up the lander.
  • 84 images of the comet are being awaited from Rosetta, which will be used to try to locate the lander. There will also be descent and touchdown images relayed from Philae to Rosetta.
  • A manoeuvre command has been sent to Rosetta to keep the Philae landing area in sight over the coming days.

Everything didn’t go to plan but it was always going to be a high risk mission.

The Philae mission looks almost certain to be coming to an end. Tomorrow we will know one way or the other whether it has survived the night.

It has been an extraordinary rollercoaster. Amid all the anxiety about the lander’s limited lifetime, behind the scenes, the science teams have been working. We are promised many fascinating results but the analysis will take time.

Even if the “hop” does not succeed and Philae ends tonight, there is no way that it can be seen as anything other than a success. History has been made. Science has been advanced. And we have taken a step closer towards understanding our cosmic origins.

It’s been a fascinating and fairly successful comet encounter.

Source: The Guardian Rosetta team makes final plans to save Philae lander – as it happened