International Space Station

(Click on this thumbnail picture for a larger image)

The International Space Station (ISS) flew over my home a few minutes ago. When you know where to look it is easy to pick out of a clear sky one or two hours before sunrise or one or two hours after sunset. The ISS circumnavigates our planet in approximately 90 minutes and appears from earth as a fast-moving light traveling from a westerly direction to an easterly direction. Today, at 5:39 am, it was very close to the centre of the sky, halfway between north and south. An app such as Sky Guide helps me keep track of ISS flyovers and the location of planets in the night sky. You can also go to the ISS Astroviewer to get an image of the present location of the ISS.

It is fascinating to think of the six astronauts racing overhead at 7.66 km/sec. Presently, the crew consists of three Russians (Roscosmos), two Americans (NASA), and one French (ESA); under the command of Robert Shane Kimbrough (NASA). This crew represents Expedition 50 and has been assigned to study several human biomedical research questions. NASA states that the purpose of this mission is to “investigate how lighting can change the overall health and well-being of crew members, how microgravity can affect the genetic properties of space-grown plants, and how microgravity impacts tissue regeneration in humans.”. The crew are the test-subjects in their research work. As the present mission nears completion, the crew have been in space for 120 to 150 days and a crew change is scheduled to occur in early May, 2017.

Cassini

Recently I wrote a sad lament for the Schiaparelli Lander, even as I praised those who had successfully inserted the Trace Gas Orbiter (TGO) into a near-perfect orbit around Mars. This orbiting communications relay and atmospheric laboratory will serve NASA scientists for the next several years and will eventually support a European Space Agency (ESA) rover on the planetary surface. TGO and the Schiaparelli lander had traveled to the Red Planet together but the lander’s fate was sealed when its landing rockets fired improperly.

On the other hand, NASA’s Cassini–Huygens spacecraft was launched in 1997 and arrived in orbit around Saturn in 2004 where both portions of the craft performed flawlessy. As planned, the Huygens lander made a successful touchdown on one of Saturn’s moons (Titan) and transmitted data throughout the landing and approximately 90 minutes of its initial time on the surface. This made Huygens the first Earth vehicle to land on the surface of any planet or moon beyond the asteroid belt of our solar system. Cassini went on to explore Titan and other moons before settling into an orbit around Saturn.

Since leaving Earth in 1997, Cassini has been an amazing spacecraft. Launched in a time when 1-mega-pixel cameras were state-of-the-art, that was the best high-resolution camera with which it could be equipped. Now, most cell-phones carry an 8 to 12 mega-pixel camera. Such are the changes that come with a 20-year mission. Cassini was the first spacecraft to orbit Saturn, and it has been able to map Saturn’s magnetosphere, has found new Saturnine moons, and studied Saturn’s atmosphere and rings with greater precision than ever before. But, the space-vehicle is getting old. In terms of how much space debris, radiation, and other hazards it has seen, relatively speaking, it is older than the last incarnation of Spock. Automobiles that are 20 years old and older are often considered antique and show up in enthusiast’s collections; this 20-year-old vehicle is still out there serving well.

Numerous remote repairs, software updates, and “farmer-fixes” have had to be performed on this machine to keep it on track; and, by the marvels of contemporary engineering, the technicians at NASA have indeed kept it on its mission. Cassini has two main engines and is still using its primary engine, but those who work on this machine had to switch it over to the back-up attitude-control-thrusters when the first set began to fail several months ago.

There is still an end of the road for even a highly successful mission like Cassini-Huygens. At the end of this month, Cassini’s thrusters will maneuver it into a position that will allow for 22 orbits close to the rings, through gaps between rings, and finally between the Saturnine atmosphere and the inner-most ring. As a Grand Finale (a term actually being used for the final days of this spacecraft), Cassini will plunge into the atmosphere in September of 2017 where it will be vaporized by the heat of friction and crushed by the pressure of the atmosphere. It will indeed be a magnificent curtain-call for one of the most successful space missions of all time.

Links used in researching this article:

https://saturn.jpl.nasa.gov/the-journey/timeline/#the-grand-finale

https://saturn.jpl.nasa.gov/the-journey/timeline

https://en.wikipedia.org/wiki/Cassini%E2%80%93Huygens

https://en.wikipedia.org/wiki/Huygens_(spacecraft)#Landing_site

https://saturn.jpl.nasa.gov/news/2947/care-and-feeding-of-an-aging-spacecraft/

An interesting hexagonal polar vortex at the north pole of Saturn:

A Robotic Spacecraft Dies

This week was supposed to be a week of good news for the Schiaparelli lander. It was expected that by this time, the Trace Gas Orbiter (TGO) would be relaying information from Schiaparelli to Earth and science experiments would be about to begin on the surface of Mars. The European Space Agency (ESA) did have success in inserting the TGO into orbit around Mars but Schiaparelli did not fare so well. Evidence points to a crash landing on Mars. ESA lost contact with the Schiaparelli craft shortly after its entry into the Martian atmosphere on October 19. ESA believes that two of three phases of the landing succeeded but that something went wrong with the third and final stage of the complex landing procedure.

Phase one of the landing was a controlled air-braking procedure in which a heat-shield allowed Schiaparelli to use the atmosphere to slow the craft and achieve a height of 10 km above the surface of the planet. Next, a 12-meter diameter parachute slowed the craft further, taking Schiaparelli to 1 km above Mars. The final phase of landing was to be a controlled burn of 9 hydrazine rockets which would fire for approximately 30 seconds and bring the craft to 2 meters above the surface, then shut-off and allow Schiaparelli to drop the last 2 meters to the surface with a relatively gentle impact.

What seems clear from the evidence gathered so far is that the hydrazine rockets fired early and did not fire long enough to allow Schiaparelli to slow to zero velocity at 2 meters above the surface. Instead, it is believed that the space-craft fell more than 2 km and landed with a velocity greater than 300 km/hr, crushing the delicate craft and perhaps causing it to explode upon impact. Images of the landing site, taken by the Mars Reconnaissance Orbiter (a NASA orbiter), show both the parachute and Schiaparelli on the surface with a larger than anticipated impact site for the spacecraft.

Meanwhile, the TGO is in its expected orbit around Mars and will go through a series of maneuvers in early 2017 to bring it into a low Mars orbit where it will begin its science missions. TGO will analyse the atmosphere of the planet looking for methane that may have been generated by life on the planet in some stage of its history. Methane could be an indicator of methane-producing bacteria that may have once thrived in water on the Martian surface thousands of years ago.

Despite the set-back of a crash landing, ESA will continue to work towards putting a rover on Mars in the year 2020. We look forward to much more Martian exploration in the years to come.

Schiaparelli

(Click on this thumbnail picture for a larger image.)

This week in solar system navigation, the Schiaparelli Lander was given the necessary software to allow it to land on Mars. Descent and soft touchdown on Mars will be guided by the commands that were uploaded on October 7^th.  The fact that such commands can be transmitted and incorporated into an on-board computer, more than 150 million km (9 light minutes) from Earth is a feat in itself. (Man, I would not want to pay those data roaming fees!) At the time, Schiaparelli and its parent vehicle, the Trace Gas Orbiter, were conjoined and enroute to the Red Planet. Together, these two spacecraft are part of the European Space Agency’s (ESA) ExoMars mission. Schiaparelli is scheduled to land on Mars on October 19 at 8:40 am MDT, while the Trace Gas Orbiter (TGO) will insert itself into orbit around Mars and relay information from the lander. The TGO will also have several science instruments on board with which it will analyze the thin atmosphere of the planet and will play a role in relaying data from other landing missions including a 2020 ESA Rover.

ESA is inviting media outlets to follow the progress of this mission including separation of the two vehicles on October 16^th, Schiaparelli landing on the 19^th, and summary on October 20^th. The media announcement can be seen here. Watch for more exciting news in the days to come, but for now you can watch an animation of the landing on the same media webpage.

The Future of Space Exploration

Jupiter and Europa

The 15^th to 18^th centuries were a time of unprecedented exploration of our world. Europeans, with a healthy sense of curiosity, and driven by a desire to conquer new worlds, were the primary instigators. Today, we live in a similar time of exploration as countries and private corporations turn their eyes to our solar system. Led by many organizations from around the world, there is a greater sense of cooperation in this age of discovery. The National Aeronautics and Space Agency (NASA), European Space Agency (ESA), Russian Federal Space Agency (RFSA), Chinese National Space Agency (CNSA), and Japan Aerospace Exploration Agency (JAXA) are all making a mark in space exploration.

NASA is presently developing an Asteroid Redirect Mission in which they will identify, capture, and redirect a near-Earth asteroid. The goal is to capture an asteroid and place it in orbit around the moon so that scientists might study it for generations to come.[1] NASA also plans to send a mission to Europa, one of the large moons orbiting Jupiter. It takes 7 to 10 years to reach the Jovian system and the plan is to launch in the early 2020s, so don’t expect results immediately, but Europa is considered one of the more likely locations for simple extra-terrestrial life because of its large frozen ocean.[2]

ESA too has plans for a Jovian mission. Their spacecraft will visit three of Jupiter’s moons: Ganymede, Callisto, and Europa. The rationale for this trip is that all three moons likely contain water and might support life.[3] ESA has also expressed interest in establishing a lunar base on our own moon that would serve as a research base, much like the International Space Station. It would make a great jumping off point for even greater space exploration that might include missions to other star systems.[4]

In 2013, the Chinese National Space Agency was the first agency to soft land a spacecraft on the moon since the Russians last did in 1976 (Luna 24). CNSA presently has a lunar rover called Chang'e 3 on the moon’s service and they have stated that they plan many more lunar missions including some sample return missions.[5]

JAXA, in collaboration with ESA, will soon launch a Mercury orbiter that will study the magnetosphere of that planet.[6] Because of its proximity to the sun, and the difficulty of shielding instrumentation from extreme radiation, little is known about this planet; and the JAXA mission will be highly significant.

All of these missions will be of great interest as we watch them unfold over the next decades. I plan to watch each with great expectation, starting with the ExoMars show that has already begun.

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[1] http://www.nasa.gov/about/whats_next.html

[2] http://www.nasa.gov/jpl/nasas-europa-mission-team-joins-forces-for-the-first-time

[3] http://all-that-is-interesting.com/europe-space

[4] http://all-that-is-interesting.com/europe-space

[5] https://en.wikipedia.org/wiki/Chang%27e_3

[6] http://global.jaxa.jp/projects/sat/bepi/index.html

ExoMars

ExoMars is a "Programme to investigate the Martian environment and to demonstrate new technologies paving the way for future Mars sample return missions."[1] The European Space Agency successfully launched their two craft on March 14 on a Russian Proton M rocket and has received signals indicating that the launch was successful. The two craft will continue to travel together for the next seven months and will then separate for two unique tasks shortly before arrival at Mars. The orbiter will measure trace gasses in the Martian atmosphere and will particularly look for gasses such as methane that could be evidence of life on the red planet. The orbiter will also seek to identify the source of these gasses.

Three days before orbit insertion, the two space-craft will separate allowing the Schiaparelli lander to aerobrake, deploy a parachute, use its heatshields, and land in the Meridiani Planum. This area is known to contain "hematite, an iron oxide that, on Earth, almost always forms in an environment containing liquid water."[2]

The Meridiani Planum region is significant because it has been explored by the Opportunity Rover[3] and a good deal of information about potential locations of water and minerals has been determined. If significant amounts of water can be located, it may be possible to use that water to generate electricity and rocket-fuel so that a spacecraft might make a return voyage. To this point, all missions to Mars have been one-way trips. This is what ESA means when they say that this mission could “pave the way for future Mars sample return missions.” ESA, NASA, SpaceX, and the entire scientific community will be watching this mission for the next several months.

Works Cited:

ESA: Robotic Exploration of Mars; “ExoMars.”

Science News, March 11, 2016

Wikipedia, “Meridiani Planum.”

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[1] Science News, March 11, 2016; "ExoMars Mission to Search for Signs of Life on the Red Planet"; accessed 2016-03-16; https://www.sciencenews.org/blog/science-ticker/exomars-mission-search-signs-life-red-planet?tgt=nr

[2] ESA: Robotic Exploration of Mars; “ExoMars”; accessed 2016-03-16; http://exploration.esa.int/mars/47852-entry-descent-and-landing-demonstrator-module/

[3] Wikipedia, “Meridiani Planum,” accessed 2016-03-16; https://en.wikipedia.org/wiki/Meridiani_Planum

Farewell Philae

The European Space Agency has had no new news on the Philae Lander since July 20^th. It seems safe to say that we should bid Philae a fond farewell. The Rosetta mission to Comet 67P/Churyumov-Gerasimenko has accomplished many of its aims; but, the lander achieved only a small portion of its goals due to a bouncy landing on the comet. The comet has very weak gravity and so it was difficult, to say the least, to achieve a landing. The landing could be compared to dropping a Wham O Superball off of a skyscraper and predicting where it would land. Philae was able to send back 57 hours of data and photos from three locations on the comet as it bounced, rocked, and rolled its way to an unstable resting place and then “collected its thoughts” regarding its unexpected position. ESA had expected that they would have much more time to collect data sent from Philae. The “little lander that could” was supposed to rest comfortably in a place where the sun would shine on its solar panels and provide it with plenty of power. But a troublesome cliff that blocked the activity of the solar cells proved too difficult to overcome.

Meanwhile, Rosetta, the Comet orbiter and companion vehicle to Philae has sent back a wealth of data and photos. (See the links here and here as well.)  Rosetta is relaying information that shows how a comet responds to solar winds as it gets closer to our sun. Rosetta, along with Philae, has also shown that the comet itself is not magnetised, answering one of the great questions about comets and their activity.

The European Space Agency has truly sparked our collective imagination regarding comets in our solar system. They have faithfully exhibited the pioneering and exploratory spirit that shows humanity at its best. We thank them for their work and their expansion of our knowledge regarding science and the dynamics of comets.

Making Scientific Discovery Interesting

The Making of Ambition

Lukasz Sobisz, is the Technical Director of Simulation for Platige Image's film, Ambition. The film is directed by Tomek Baginski and stars Aidan Gillen and Aisling Franciosi. In an interview about the European Space Agency's Rosetta Mission and the accompanying film, Ambition, Sobisz expressed his surprise that the European Space Agency would need the creative skills of the film-making company for which he works.

I'm very surprised you need something like this at all now. Mankind sends a probe into space to catch a comet and land on it, and we need a great director, film, and actors to convince people this is interesting.1

Works Cited:
Ambition. Directed by Tomak Baginski. Performed by Platige Image. 2014.
The Making of Ambition. Directed by Wojciech Jagiello. Performed by Lukasz Sobisz. 2014.

1 (Sobisz 2014)

Rosetta and Philae: Hello My Friend, Hello

Rosetta and Philae Communicating Again

In November of 2014, the Rosetta spacecraft delivered the Philae lander to the surface of Comet 67P/Churyumov-Gerasimenko (see my previous blog here). This represented the first soft landing of a spacecraft onto a comet. This in itself was a great accomplishment despite the fact that the mission did not go quite as planned. The Philae lander was intended to send back data on the composition of the comet but landed in a region where its solar panels were shaded by a cliff and, after 57 hours of operation, it could not recharge sufficiently to achieve all of its science operations. The onboard computers powered down into hibernation mode and its orbiting partner, the Rosetta spacecraft lost radio contact with the lander.

However, as anticipated, as the comet has continued its approach to the sun, and solar energy has become more intense, the Philae lander has been able to recharge sufficiently to reconnect with the Rosetta orbiter. The European Space Agency (ESA) has confirmed that on June 19, 2015 several packets of lander information were delivered to Rosetta1. The two spacecraft are again communicating and this is a very hopeful sign for the mission analysts. The comet will make its closest approach to the sun on August 13 and the agency is hopeful that the increasing solar intensity will allow the lander to continue to gain charging capabilities and restart its science operations.

Meanwhile, the Rosetta spacecraft continues to send images and scientific data to earth as the ESA has extended its mission until September 2015. Rosetta will continue sending back images and data related to the comet while anticipating more data from the Philae lander. The European Space Agency continues to dream about how best to utilize both vehicles and is now considering landing Rosetta on the comet at the end of its lifespan. The ESA even has a cool mini-movie that addresses the importance of such missions that is designed to inspire ambition. Check it out here.

1 http://blogs.esa.int/rosetta/2015/06/19/rosetta-and-philae-in-contact-again/

Sleep in Heavenly Peace

"Oh little town of Bethlehem, how still we see thee lie. Above thy deep and dreamless sleep the silent stars go by."

Earlier this week, the Rosetta spacecraft reached the end of a ten year journey and delivered the Philae lander to the surface of Comet 67P/Churyumov-Gerasimenko. After a bouncy landing in the open planes, the lander came to rest too close to a cliff to recharge its batteries with solar panels. This caused the computers on the washing-machine sized vehicle to power down into hibernation mode. Mission scientists are hopeful that it may yet achieve a better position relative to our sun and charge its batteries enough to wake up. But, for now, it must slumber in deep heavenly, frigid, peace.

Meanwhile, the comet, barely perturbed by the added weight and jostlings to its orbital path, continues on in a slow arc around the sun. This trajectory will sling it close to the sun and then hurl it back out beyond the orbit of Jupiter. The Rosetta spacecraft, like a dog whose master has died, will remain close beside, looking for some sign of life. The little lander that could is now one more piece of interplanetary material circling the sun and waving to earth as it flies by each 6.5 years. As it sails past we salute the spirit of those who served her so long and so well. We greet with honour this marvel of engineering that has once more excited dreams of far off worlds and places unexplored.

"Silent night, holy night, all is calm, all is bright. . . . sleep in heavenly peace."