This dark, tangled web is an object named SNR 0454-67.2. It formed in a very violent fashion — it is a supernova remnant, created after a massive star ended its life in a cataclysmic explosion and threw its constituent material out into surrounding space. This created the messy formation we see in this NASA/ESA Hubble Space Telescope image, with threads of red snaking amidst dark, turbulent clouds.
SNR 0454-67.2 is situated in the Large Magellanic Cloud, a dwarf spiral galaxy that lies close to the Milky Way. The remnant is likely the result of a Type Ia supernova explosion; this category of supernovae is formed from the death of a white dwarf star, which grows and grows by siphoning material from a stellar companion until it reaches a critical mass and then explodes.
As they always form via a specific mechanism — when the white dwarf hits a particular mass — these explosions always have a well-known luminosity, and are thus used as markers (standard candles) for scientists to obtain and measure distances throughout the Universe.
The Copernicus Sentinel-1 mission takes us over Mexico City. This huge, densely-populated capital can be seen in the top right of the image. It is home to almost nine million people, with the Greater Mexico City area recording a population of over 21 million. This makes it the largest Spanish-speaking city in the world.
This striking image has been created using three Copernicus Sentinel-1 acquisitions from 28 July, 27 August and 26 September 2018, overlaid in red, green and blue, respectively. Where we see explosions of colour, changes have occurred between the different acquisitions.
In the left of the image, three bodies of water are shown in black: Villa Victoria, Valle de Bravo, and Tepetitlán. Water is significant to the development of Mexico City, which is thought to have been built over a lake by the Aztecs around 1325.
Today, the city finds itself in a precarious situation in terms of water supply in spite of the regular flash floods and heavy rainfall it experiences during the wet season from June and September.
In the top right, we can see the round structure of El Caracol meaning ‘the snail’ in Spanish. Currently used as a reservoir for industrial facilities within Mexico City, there are plans for this to become a wastewater treatment plant. A 62 km-long sewer tunnel is also due to begin operating this year.
The Cumbres del Ajusco national park is shown to the southwest of the capital, in an area of the image that shows colourful dots forming a circle. Famous for being up to almost 4000 m above sea level at its highest elevation, it is one of many national parks surrounding the capital.
Volcanoes are also dotted around this area. Popocatépetl, to the south east of Mexico City, last erupted in September 2018.
Sentinel-1 is a two-satellite mission to supply the coverage and data delivery needed for Europe’s Copernicus environmental monitoring programme. The satellites each carry an advanced radar instrument to provide an all-weather, day-and-night supply of imagery of Earth’s surface.
This image is also featured on the Earth from Space video programme.
At just before 9pm Central European Time on 26 November, Mars will receive a new visitor: NASA’s InSight lander.
Short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, InSight will be the first Mars mission dedicated to studying the planet’s interior, including sensing Mars quakes. Learning about the interior of the planet will inform scientists about the early formation of the rocky planets in our own Solar System, as well as the evolution of exoplanets orbiting other stars.
Since InSight’s study is focused on sensing the planet’s interior, surface geology is not such an important factor in deciding the landing site as it is for other missions. Therefore, it is targeting a flat, stable surface in the Elysium Planitia region, which is captured in this wide field view from ESA’s Mars Express Visual Monitoring Camera taken on 29 February 2016 (click here for a labelled view).
InSight will target a landing site centred at 4.5ºN/135.9ºE, about 600 km from Gale Crater, the region that NASA’s Curiosity rover is exploring.
In the image shown here, Elysium Planitia is located roughly between the dark features at the bottom right (which includes Gale Crater), and the brighter arc-shaped feature above, to the right of the centre of the image, which is the location of volcano Elysium Mons. The north polar ice cap is seen at the top of the image.
ESA has already been supporting InSight’s mission with its ground station network throughout the cruise to Mars, following the mission’s launch in May 2018. The joint ESA-Roscosmos Trace Gas Orbiter (TGO) of the ExoMars mission, which arrived at Mars in October 2016, is ready to support data relay from InSight several times per day once it has landed safely, as required. Mars Express will also be prepared to support, on NASA’s request, ad hoc relay contacts with InSight in case of emergency needs.
TGO will also act as a data relay for the ExoMars rover mission in 2021, for which the landing site was recommended earlier this month as Oxia Planum. A region that is thought to have hosted vast volumes of water in the past, it is an ideal location to search for clues that may help reveal the presence of past life on Mars.
NASA also just announced the landing site for its Mars 2020 rover, which is set to explore an ancient river delta in Jezero Crater. Moreover, the rover will collect rock and soil samples and store them in a cache on the planet's surface. NASA and ESA are studying future mission concepts to retrieve the samples and return them to Earth, setting the stage for the next decade of Mars exploration.
More information about InSight and how to follow the landing: https://mars.nasa.gov/insight/
This image of ESA astronaut Alexander Gerst training onboard the International Space Station, was shared on Alexander's social media channels on 24 November 2018.
Alexander said "Almost like an evening mountain bike ride in the forest. Oh well. What we do to develop new textiles and instruments that will help keep both astronauts and earthlings healthy."
Séance de questions/réponses informelle entre l'astronaute de l'ESA Léopold Eyharts et les jeunes passionnés d'espace dans le cadre du SpaceTalks Espace Air Passion à Angers (49).
This walking and hopping robot is currently being tested in ESA’s Mars Yard.
SpaceBok is a quadruped robot designed by a Swiss student team from ETH Zurich and ZHAW Zurich, under the supervision of Professor Marco Hutter and PhD student Hendrik Kolvenbach, for future missions to the Moon or Mars.
“Legged robots can traverse unstructured terrain and could be used to explore areas of interest, such as craters, which rovers are unable to reach,” explains team member Patrick Barton. “As they are very versatile, they can change gait to adapt to different terrain.”
“In contrast to other legged robots, SpaceBok is primarily built for hopping,” adds team member Elias Hampp. “While this is not particularly useful on Earth, it could reach a height of four metres on the Moon. This would allow for a fast and efficient way of moving forward.”
““We are currently implementing and testing vision sensors, to increase SpaceBok’s autonomy and robustness,” says team member Radek Zenkl.
ESA’s 8 x 8 m Mars Yard ‘sandbox’, filled with different sizes of sand, gravel, and rock, is part of the Planetary Robotics Laboratory at the Agency’s ESTEC technical centre in Noordwijk, the Netherlands.
See video of the SpaceBok here.
The sun set on a week of trials for the ExoMars rover prototype named Charlie (in the foreground). The first of two field trials for the mission, known as ExoFiT, took place in the Tabernas desert in Spain between 13-26 October.
While Charlie was located in Spain, mission operators and instrument scientists were based over 1000 km away at mission control in Harwell, UK, near ESA’s ECSAT centre where ExoFit was managed. The distance was crucial as teams operating a rover on the Martian surface must contend with infrequent communication possibilities and must run science operations with what little information they have. The rover itself is designed to carry out activities such as a traverse or observations in between communication blackouts as well as send data to Earth in preparation for the next martian day.
During the 10-day trial, the team practised driving the rover off its landing platform (in the background of this image), targeting sites of interest, and sampling rocks. Decisions were made based on data transmitted by the rover together with maps of the terrain.
Naturally, the team encountered technical difficulties, to be expected in real test conditions. Rainfall disrupted events and forced the team to adapt and optimise their time. In the second week, the team managed to finish activities scheduled for two martian days in a single day.
The scenarios in general tested the rover’s radar instrument, close-up imager, panoramic mast imager and drill, with more specific tests aimed at replicating what will be performed on the martian surface. Once on the Red Planet, the rover drill beneath the surface to look for signs of life.
A lot is learned during these simulation studies to fine-tune equipment and train mission specialists. The issues encountered in the field trial will be addressed and tested again in a second field campaign introducing more complex autonomous rover operations.
Set for February 2019, the second field trial will take place in the Atacama desert of Chile. Atacama is one of the most similar terrains on Earth to Mars, with the added benefit of drier weather and the nearby European Southern Observatory’s Paranal Observatory over the Tabernas desert.
The operational challenges observed provide valuable inputs for the ExoMars rover and other planetary rovers such as the Sample Fetch Rover of the NASA-ESA Mars Sample Return mission. Currently in the concept phase, ESA is working with international partners to achieve its vision of Europe’s expanding role in space exploration.
ESA astronaut Alexander Gerst captured this image of Mt. Taranaki from the International Space Station on shared it on his social media channels saying: "How come every time I climbed Mt Taranaki in New Zealand, it was covered in clouds?"
Week in images
26 - 30 November 2018