OrbitalHub

ESA dixit:

“Animation visualizing milestones during the launch of the ExoMars 2016 mission and its cruise to Mars. The mission comprises the Trace Gas Orbiter and an entry, descent and landing demonstrator module, Schiaparelli, which are scheduled to be launched on a four-stage Proton-M/Breeze-M rocket from Baikonur during the 14–25 March 2016 window.

About ten-and-a-half hours after launch, the spacecraft will separate from the rocket and deploy its solar wings. Two weeks later, its high-gain antenna will be deployed. After a seven-month cruise to Mars, Schiaparelli will separate from TGO on 16 October. Three days later it will enter the martian atmosphere, while TGO begins its entry into Mars orbit.

[The second animation presents] The paths of the ExoMars 2016 Trace Gas Orbiter (TGO) and the Schiaparelli entry, descent and landing demonstrator module arriving at Mars on 19 October (right and left, respectively). The counter begins at the start of a critical engine burn that TGO must conduct in order to enter Mars orbit. The altitude above Mars is also indicated, showing the arrival of Schiaparelli on the surface and the subsequent trajectory of TGO. The orbiter’s initial 4-day orbit will be about 250 x 100 000 km. Starting in December 2016, the spacecraft will perform a series of aerobraking manoeuvres to steadily lower it into a circular, 400 km orbit (not shown here).”

Video credit: ESA

ESA dixit:

“The Sentinels are a fleet of satellites designed to deliver the wealth of data and imagery that are central to the European Commission’s Copernicus programme.

This unique environmental monitoring programme is making a step change in the way we view and manage our environment, understand and tackle the effects of climate change and safeguard everyday lives. It serves European citizens, both directly through its products and applications, and indirectly through social, economic and environmental benefits.

Carrying a suite of cutting-edge instruments, Sentinel-3 will measure systematically Earth’s oceans, land, ice and atmosphere to monitor and understand large-scale global dynamics. It will provide essential information in near-real time for ocean and weather forecasting.

The mission is based on a two identical satellites orbiting in constellation for optimum global coverage and data delivery. For example, with a swath width of 1270 km, the ocean and land colour instrument will provide global coverage every two days.

With a focus towards our oceans, Sentinel-3 measures the temperature, colour and height of the sea surface as well as the thickness of sea ice. These measurements will be used, for example, to monitor changes in sea level, marine pollution and biological productivity.

Over land, this innovative mission will provide a bigger picture by monitoring wildfires, mapping the way land is used, provide indices of vegetation state and measure the height of rivers and lakes – complementing the high-resolution measurements of its sister mission Sentinel-2.

While Sentinel-3 will provide enhanced continuity of satellites such as Envisat and Spot, the sheer breadth of data from this new mission means that it is set to be the workhorse for Copernicus.

The mission is the result of close collaboration between ESA, the European Commission, Eumetsat, France’s CNES space agency, industry, service providers and data users.

As a prime example of Europe’s technological excellence, the two Sentinel-3 satellites have been designed and built by a consortium of around 100 companies under the leadership of Thales Alenia Space, France.

Once commissioned in orbit, ESA and Eumetsat will manage the mission jointly, where ESA processes land products and Eumetsat the marine products for application through the Copernicus services. Data are free of charge and open to users worldwide.”

Video credit: ESA

NASA dixit:

“Dwarf planet Ceres is shown in these false-color renderings, which highlight differences in surface materials. Images from NASA’s Dawn spacecraft were used to create a movie of Ceres rotating, followed by a flyover view of Occator Crater, home of Ceres’ brightest area.”

Wikipedia dixit:

“Ceres (minor-planet designation: 1 Ceres) is the largest object in the asteroid belt, which lies between the orbits of Mars and Jupiter. Its diameter is approximately 945 kilometers (587 miles), making it the largest of the minor planets within the orbit of Neptune. The thirty-third-largest known body in the Solar System, it is the only one identified orbiting entirely within the orbit of Neptune that is a dwarf planet. Composed of rock and ice, Ceres is estimated to comprise approximately one third of the mass of the entire asteroid belt. Ceres is the only object in the asteroid belt known to be rounded by its own gravity. From Earth, the apparent magnitude of Ceres ranges from 6.7 to 9.3, and hence even at its brightest, it is too dim to be seen with the naked eye, except under extremely dark skies.

Ceres was the first asteroid discovered, by Giuseppe Piazzi at Palermo on 1 January 1801. It was originally considered a planet, but was reclassified as an asteroid in the 1850s when many other objects in similar orbits were discovered.

Ceres appears to be differentiated into a rocky core and icy mantle, and may have a remnant internal ocean of liquid water under the layer of ice. The surface is probably a mixture of water ice and various hydrated minerals such as carbonates and clay. In January 2014, emissions of water vapor were detected from several regions of Ceres. This was unexpected, because large bodies in the asteroid belt do not typically emit vapor, a hallmark of comets.

The robotic NASA spacecraft Dawn entered orbit around Ceres on 6 March 2015. Pictures with a resolution previously unattained were taken during imaging sessions starting in January 2015 as Dawn approached Ceres, showing a cratered surface. Two distinct bright spots (or high-albedo features) inside a crater (different from the bright spots observed in earlier Hubble images) were seen in a 19 February 2015 image, leading to speculation about a possible cryovolcanic origin or outgassing. On 3 March 2015, a NASA spokesperson said the spots are consistent with highly reflective materials containing ice or salts, but that cryovolcanism is unlikely. On 11 May 2015, NASA released a higher-resolution image showing that, instead of one or two spots, there are actually several. On 9 December 2015, NASA scientists reported that the bright spots on Ceres may be related to a type of salt, particularly a form of brine containing magnesium sulfate hexahydrite (MgSO4·6H2O); the spots were also found to be associated with ammonia-rich clays.”

Video credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

ESA dixit:

“Liftoff of Vega VV06 carrying LISA Pathfinder from Europe’s Spaceport, French Guiana, at 04:04 GMT/05:04 CET on 3 December 2015. Vega will place LISA Pathfinder into an elliptical orbit around our planet. Then, the spacecraft will use its own propulsion module to raise the highest point of the orbit in six stages. The last burn will propel the spacecraft towards its operational orbit, around a stable point called L1, some 1.5 million km from Earth towards the Sun.

Once on its final orbit, LISA Pathfinder will test key technologies for space-based observation of gravitational waves. These ripples in the fabric of spacetime are predicted by Albert Einstein’s general theory of relativity but have not yet been directly detected.

To demonstrate the fundamental approach that could be used by future missions to observe these elusive cosmic fluctuations, LISA Pathfinder will realize the best free-fall ever achieved in space. It will do so by reducing all the non-gravitational forces acting on two cubes and monitoring their motion and attitude to unprecedented accuracy.”

Video credit: ESA/Arianespace

ESA dixit:

“The AIM spacecraft will be launched in October 2020 on board a Soyuz-Fregat launch vehicle from Kourou. After launch and one or more deep-space manoeuvres, AIM will arrive at Didymos in June 2022, some months before DART’s impact.After arrival, the AIM spacecraft will transition into a heliocentric co-flying orbit, from which it will observe the binary system to derive a high-resolution 3D model of the asteroid, determine its mass and dynamical state, and characterise its surface and shallow sub-surface properties by means of a thermal infrared imager and high-frequency radar. This first characterisation phase would last for a couple of months and be conducted from a distance of between 35 to 10 km from the asteroid. Following this, the AIM spacecraft will release a number of CubeSats and a lander which is based on DLR’s MASCOT lander used for the JAXA Hayabusa-2 mission. The lander will carry out a detailed characterization of the deep-interior structure of the asteroid by means of a low-frequency bistatic radar. Approximately two weeks before DART impact, the AIM spacecraft would be moved to an orbit about 100 km from the asteroid to safely conduct impact observations. After the impact, a second characterisation phase would conclude the mission.

The AIM spacecraft is based on a very simple design with fixed solar arrays and a fixed high-gain antenna. The baseline propulsion system uses a bi-propellant (MMH/MON) fuel with 24 thrusters each capable of producing 10 N of thrust. A separate Helium tank would keep the four 60 l propellant tanks pressurized. Power is generated by two deployable, fixed solar arrays with an output of 165 W each at a distance of 2.2 AU from the Sun, and a total panel surface of 5.6 m². The total spacecraft dry mass would be about 420 kg and the propellant mass about 292 kg.

The target of the AIM mission is asteroid 65803 Didymos (1996 GT), an Apollo-type near-Earth orbit (NEO) with a perihelion that is just below the aphelion radius of Earth orbit. Didymos is a binary body; the primary body has a diameter of around 750 m and a rotation period of 2.3 hours, while the secondary body had a diameter of around 170 m and rotates around the primary at a distance of 1.2 km in 12 hours. Study of the Didymos moon should offer valuable insights into the origins of our Solar System, and help scientists develop planetary defence strategies against any incoming asteroids in the future. Informally called ‘Didymoon’, the asteroid is nearly three times larger than the body thought to have caused the 1908 Tunguska impact in Siberia, the largest impact in recorded history. An equivalent asteroid striking Earth would be well into the ‘city-killer’ class, leaving a crater of at least 2.5 km diameter and causing serious regional and climate damage. The 2013 Chelyabinsk airburst, whose shockwave struck six cities across Russia, is thought to have been caused by an asteroid just 20 m in diameter.”

Video credit: ESA

NASA dixit:

“Researchers at NASA’s Jet Propulsion Laboratory are developing the Buoyant Rover for Under-Ice Exploration, a technology that could one day explore oceans under the ice layers of planetary bodies. The prototype was tested in arctic lakes near Barrow, Alaska.”

Video credit: NASA JPL