Space Sunday: day of remembrance, seeing Mars and flying over Ceres

This week marked a sombre period in the annals of NASA’s history. In a period of just 7 days – albeit spread across 50 years – America lost 17 astronauts in just three space flight related tragedies. Every year, the US space agency marks this loss of life – the results of the Apollo 1, Challenger and Columbia accidents – with a special Day of Remembrance on the 27th January. This year’s event was particularly poignant in that 2016 marks the 30th anniversary of the Challenger disaster.

It was on January 27th, 1967, that NASA suffered the first of these tragedies when, during a pre-launch rehearsal of what was intended to be the first manned flight of the Apollo Command and Service modules, a fire broke out inside the Command Module as the vehicle sat on the pad of Cape Kennedy Air Force Station Launch Complex 34. A combination of a pure oxygen atmosphere at a high internal PSI, and highly flammable materials used in the vehicle’s interior construction resulted in the deaths of Command Pilot Virgil I. “Gus” Grissom, Senior Pilot Edward H. White II, and Pilot Roger B. Chaffee in just 16 seconds.

Apollo 1: (l-to-r) Virgil I. "Gus" Grissom, Edward H. White II, and Roger B. Chaffee standing before the Apollo 1 launch vehicle, on January 17th, 1961
Apollo 1: (l-to-r) Virgil I. “Gus” Grissom, Edward H. White II, and Roger B. Chaffee standing before the Apollo 1 launch vehicle, on January 17th, 1961

Nineteen years later, on January 28th, 1986, NASA suffered its largest loss of life in a space mission up until that point in time. It occurred when Space Launch System mission 51L, the 25th flight in the space shuttle programme and the 10th flight of the shuttle orbiter vehicle Challenger – regarded as the veteran of the fleet, having flown more orbital missions than the other three orbiter vehicles at that time – exploded 73 seconds after launch, resulting in the loss of all seven crew.

The Challenger 7: (l-to-r) Sharon Christa McAuliffe, Gregory Jarvis, Judith Resnik, Francis "Dick" Scobee, Ronald McNair, Michael Smith and Elison Onizuka, during a countdown training exercise on January 9th, 1986
The Challenger Seven: (l-to-r) Sharon Christa McAuliffe, Gregory Jarvis, Judith Resnik, Francis “Dick” Scobee, Ronald McNair, Michael J. Smith and Ellison Onizuka, during a countdown training exercise on January 9th, 1986

Tragedy struck the space shuttle programme again on February 1st, 2003, when the space shuttle Columbia broke-up following re-entry into the Earth’s atmosphere at the end of mission STS-107, killing all seven crew. On board were Commander Rick Husband, Pilot William McCool, Payload Commander Michael Anderson, Mission Specialists Laurel Blair Salton Clark, Kalpana Chawla, David M. Brown, and Payload Specialist  Ilan Ramon, a colonel in the Israeli Air Force and the first Israeli astronaut.

The official STS-107 crew photo (l-to-r): Brown, Husband, Clark, Chawla, Anderson, McCool, Ramon
The official STS-107 crew photo (l-to-r): David M. Brown, Rick Husband, Laurel Blair Salton Clark, Kalpana Chawla, Michael P Anderson, William C. McCool, and Ilan Ramon

There have of course been other lives lost within the fraternity of astronauts and cosmonauts over the decades. However, these three tragedies perhaps stand larger than others because NASA has always undertaken its missions in the full glare of the public and media spotlight. Apollo 1, for example, was the headline mission for America meeting President Kennedy’s requirement for “landing a man on the Moon and returning him safely to the Earth” before the end of the decade. Similarly, STS-51L, the Challenger mission, had been specifically engineered to be in the public eye, featuring as it did the first teacher in space, Sharon Christa McAuliffe.

McAuliffe had been selected from more than 11,000 applicants to participate in NASA’s Teacher in Space Project, initiated by US Present Ronald Reagan and intended by NASA to rejuvenate public interest in the space programme, which has been declining steadily since the first space shuttle flight in 1981. The gamble paid off and McAuliffe, became a media sensation, attracting world-wide public interest in STS-51L; so much so that it has been estimated that around 17% of Americans watched Challenger’s lift-off live on television as a direct result of McAuliffe’s presence on the mission, and that around 85% heard about the disaster within an hour of it occurring (and if that doesn’t sound unusual, remember 1986 was well before the Internet and media revolution what has placed information and news at our fingertips wherever we are).

It could be argued – particularly with regards to Challenger, and also with Apollo 1, that the disaster could have been avoided. Warnings about the precise type of failure which caused the loss of Challenger date back as far as 1971, which tests carried out in 1977 revealing the risk of what because known as an O-ring failure being inherent in the design of the shuttle’s solid rocket boosters.

Things are less clear in the case of the Columbia tragedy; while it has been suggested that a rescue mission might have been mounted using the shuttle orbiter Atlantis, which was being prepared for a mission due to lift-off at the start of March, 2003. However, in order to get the vehicle flight ready for a launch ahead of the February 15th deadline (the point at which lithium hydroxide, a critical part of the systems used to remove carbon dioxide from the air in a space vehicle, would run out aboard Columbia), was itself fraught with risks.

But whether they could be avoided or not, these three disasters remind us that the cost of becoming a space faring civilisation – something which could be vital to our survival – is not without risk. Which is why I’ll close this part of Space Sunday with the words of Francis R. Scobee, the Commander of STS-51L, written shortly before his death aboard the Challenger:

Continue reading “Space Sunday: day of remembrance, seeing Mars and flying over Ceres”

Space update: seeking planet X, examining comets and sifting sand

CuriosityNASA’s Curiosity rover has been sampling the sands of the “Namib Dune” the vehicle has been studying / circumnavigating for the last few weeks as it studies an extensive dune field which is slowly making its way down the slopes of “Mount Sharp” on Mars at the rate of about a metre per year.

“Mount Sharp”, more formally called Aeolis Mons, is the huge mound of material gathered against the central impact peak of Gale Crater. It forms the rover’s primary mission target in its quest to better understand conditions on Mars down through the ages, and to look for areas which at some point in the planet’s past, may have had all the right conditions – minerals, chemicals, water, heat, shelter, etc., – which might have allows life to arise.

The dune field on the north-east flank of “Mount Sharp” is of considerable interest to scientist, as it is the first genuine dune field to be studied on another world, and obtaining a clearer understanding of how the Martian wind moves sand could lead to a clearer picture of how big a role the wind plays in depositing concentrations of minerals often associated with water across the planet, and by extension, the behaviour and disposition of liquid water across Mars.

Tracks on a sand dune: this image from Curiosity's front Hazard Avoidance Camera (Hazcam) shows the rover's tracks on the same of "Namib Dune" as it starts sample gathering
Tracks on a sand dune: this image from Curiosity’s front Hazard Avoidance Camera (Hazcam) shows the rover’s tracks on the same of “Namib Dune” as it starts sample gathering

On January 12th, the rover reached a target area for sample gathering dubbed “Gobabeb”, and even this presented a challenge. Curiosity had to manoeuvre up onto the dune, and then turn in place in order to start sample gathering operations. This meant a cautious approach to the location, initially “scuffing” the sand to obtain and indication of its depth and composition (loose firm material). After this the rover gently edged onto the sand and deployed the robot arm to use its small scoop in only its second major sample gathering exercise, which took place on January 14th.

The sand gathered by the operations well be sorted within the CHIMRA system inside the robot arm, which uses a series of sieves to divide the sand grains by coarseness. Once sorted, the samples are delivered to the rover on-board chemical and analysis systems  – ChemMin, the Chemical and Mineralogical laboratory and SAM, the Sample Analysis at Mars suite – for examination.

A second sample of sand was gathered on January 19th, and is currently awaiting processing.

CHIMRA
CHIMRA – the Collection and Handling for In-Situ Martian Rock Analysis device attached to the turret at the end of Curiosity’s robotic arm, processes samples acquired from the built-in scoop (red) and the drill, which is not shown but is also part of the turret. CHIMRA also delivers samples to the analytical lab instruments inside the rover. Two paths to get material into CHIMRA are shown (the scoop delivers material to the location marked at the bottom, and the drill deposits material to the sample transfer tube shown at top). Also marked are the location of the vibration mechanism used to shake the turret and cause the sample to move inside CHIMRA, and the portion box (yellow) from which the material processed through a sieve is delivered to the analytical lab instruments.

Europe Joins Dream Chaser

In my last Space Sunday report, I covered the news that Sierra Nevada Corporation (SNC) will be joining SpaceX and Orbital ATK in supporting US work to delivery supplies to, and remove waste from, the International Space Station.

As a part of a new contract which commences in 2019 and runs until 2024, the expected end of ISS operations, SNC will utilise an unmanned cargo version of its Dream Chaser “mini shuttle”, which is based on a lifting body design, to carry up to 5 tonnes of material to the space station. Now Europe has officially joined SNC as a strategic partner.

The Drem Chaser Cargo, bult by SNC, and the International Berth and Docking Mechanism, to be supplied to SNC for Dream Chaser flights by the European Space Agency
The Dream Chaser Cargo, built by SNC, and the International Berth and Docking Mechanism, to be supplied to SNC for Dream Chaser flights by the European Space Agency

SNC and Europe have been looking at options for Dream Chaser development since SNC lost out to SpaceX and Boeing to supply the crewed version of Dream Chaser to NASA for ferrying crews back and forth between the ISS and US soil. Confirmation that NASA will be using Dream Chaser for the resupply flights means that ESA can nor push ahead with developing an International Berthing and Docking Mechanism (IBDM) for Dream Chaser.

Continue reading “Space update: seeking planet X, examining comets and sifting sand”

Space Sunday: Dream Chasers Falcons, and spacewalks

The Dream chaser alongside NASA's space shuttle Atlantis
The Dream Chaser flight test article alongside NASA’s space shuttle Atlantis in 2010 (image: NASA / SNC)

NASA has announced a renewal to the current US private sector contracts to provide uncrewed resupply missions to the International Space Station (ISS) – and it came with something of a surprise.

SpaceX and Orbital ATK are the two US companies currently flying cargo resupply missions to the ISS, operating alongside Russian Progress vehicles and the Japanese H-II “Kounotori” Transfer Vehicle. Europe, which previously operated the largest cargo vehicle, the Automated Transfer Vehicle, ended ISS resupply missions in February 2015, and is now focused on supplying NASA with the Orion Service Module.

Both SpaceX, who can both launch and return up to 3.3 tonnes of cargo and trash to / from the space station using their Dragon cargo vehicle, and Orbital ATK,who can transport up to 3.5 tonnes of cargo / trash aboard their Cygnus vehicle (which burns-up on re-entering Earth’s atmosphere) have their resupply contracts renewed from 2019 through 2024, matching the extended lifetime of ISS operations. While this had been expected, the inclusion of a third vehicle, the Dream Chaser vehicle being developed by Sierra Nevada Corporation SNC surprised some.

Dream Chaser was unique among the commercial crew transportation proposals as it was based on a "lifting body" design , allowing to re-enter the Earth's atmosphere and glide to a landing on a conventional runway - aspects which still make it a very flexible vehicle
Dream Chaser was unique among the commercial crew transportation proposals as it was based on a “lifting body” design rather than a capsule system. Although launched atop a conventional rocket, the design allows it to re-enter the Earth’s atmosphere and glide to a landing on a conventional runway, making it an exceptionally versatile craft (image: SNC)

Dream Chaser was originally designed as part of NASA’s Commercial Crew Development (CCDev) programme aimed at having private sector companies provide the means of carrying crews back and forth between the space station and US soil. One of four proposals put to NASA under the programme, it was ruled out of the final selection in September 2014, with SpaceX and Boeing being chosen by NASA despite the fact that on paper, Dream Chaser offered potentially a better deal than Boeing’s CT-100 capsule.

While SNC lodged a complaint with the US Government Accountability Office (GAO) as a result of the decision, citing interference in the selection process by William Gerstenmaier, NASA’s top human exploration official, the GAO upheld the selection of SpaceX and Boeing for the crewed transport vehicles. However, NASA continued to work with SNC on various ideas for Dream Chaser, alongside of SNC looking at other options for the vehicle’s crew carrying capabilities to be put to use.

An artist's concept of the Dream Chaser Cargo docked with the ISS during a resupply flight
An artist’s concept of the Dream Chaser Cargo docked with the ISS during a resupply flight (image: SNC)

The new resupply contract will see SNC provide NASA with the uncrewed “Dream Chaser Cargo” variant of the vehicle, capable of flying up to 5 tonnes of cargo to / from orbit, As with the original crewed variant, the Dream Chaser Cargo will launch atop a rocket, but return to earth to make a conventional runway landing.

How many missions each of the three resupply vehicle types will fly is unknown; vehicles will be selected on the basis of flight / payload requirements and cost. The total cost of the contract, spilt between the three companies, is expected to be US $14 billion over the 5 years.

The Ice Volcanoes of Pluto

Scientists with NASA’s New Horizons mission have assembled the highest-resolution colour view of one of two potential cryovolcanoes spotted on the surface of Pluto, as the spacecraft hurtled by the little world in July 2015.

Informally called “Wright Mons”, the feature is about 150-160 kilometres (90-100 miles) across at its base, and about 4 km (2.5 miles) high. If it is in fact a volcano, it will be the largest such feature discovered in the outer solar system.

The feature has members of the New Horizons science team intrigued on two counts. The first is that there is a very sparse distribution of red material on its flanks. The second is that it apparently only has a single impact crater. This latter point suggests “Wright Mons” is relatively new surface feature on Pluto, while the former might suggest it is active, with ice ejected by eruptions covering the red material over time.

"Wright Mons" (the large dimple in the image on the right) and as seen in context with the rest of Pluto, may be one of two enormous cryovolcanoes on the tiny world (image: NASA/JPL / JHU/APL / SwRI)
“Wright Mons” (the large dimple in the image on the right) and as seen in context with the rest of Pluto, may be one of two enormous cryovolcanoes on the tiny world (image: NASA/JPL / JHU/APL / SwRI)

The images of “Wright Mons” were returned to Earth from New Horizons in November 2015. Since then, data from the Ralph instrument suite aboard the spacecraft has been used to add the colour details to the images, which have been composed into a new mosaic of the feature. If it and “Piccard Mons” are cryovolancoes, then they present further evidence that Pluto was (and might still be) geologically active.

Continue reading “Space Sunday: Dream Chasers Falcons, and spacewalks”

Space Sunday: dunes, rockets and asteroids

CuriosityNASA’s Mar Science Laboratory rover, Curiosity, continues to perform the first up-close study ever conducted of extraterrestrial sand dunes as it slowly explores the slopes of “Mount Sharp” dubbed the “Bagnold Dunes”.

Located on the north-west slope of the mound which lies at the centre of Gale Crater, the dunes differ from those drifts and sand fields the rover has previously encountered on Mars in terms of both their size and height – some cover an area the size of a football field and are 2 storeys high – and their general shape, something which marks them out as “classic” sand dunes.

This latter point is most evident by the dunes exhibiting a steep, downwind slope, referred to as the slip face, and which exhibits certain features of its own, such as gain fall, ripples and grain flow, as well as the dune as a whole exhibiting typical features such as the horn and toe.

For the last couple of weeks, the rover has been working its way around one dune in particular, dubbed “Namib”, which is somewhat smaller than the “high dunes” images at the start of December, but which still rises to a height of some 5 metres (16 ft). The leeward side of “Namib” in particular demonstrates the classic features of a sand dune, and helps to confirm the fact that the dunes are slowly progressing down the slope of “Mount Sharp” at a rate of about 1 metre (39 inches) a year.

The leeward side of Namib:
The leeward side of “Namib”:Horn – where sand is escaping the main dune and escaping downhill, as indicated by the ripples; Toe – the downwind extent of the dune; ripples – signs of the sand bouncing sideways over the dune as the wind blows it downslope towards the horn;  Brink – the ridge between the windward, gentle slope of the dune and the leeward, steeper slope of the dune; Grail Fall – areas where sand is blown / falls from the brink and comes to rest on the leeward slope; Gain Flow – tongue-like area indicating where large amounts of sand have slumped down the side of the dune towards the toe, again indicative of a dune in motion

The dune-investigation campaign is designed to increase understanding about how wind moves and sorts grains of sand in an environment with less gravity and much less atmosphere than well-studied dune fields on Earth. Such an understanding of how the wind moves sand could lead to a clearer picture of how big a role the Martian wind played in depositing concentrations of minerals often associated with water across the planet, and by extension, the behaviour and disposition of liquid water across Mars.

This rather odd-looking image is a foreshortened 360-degree view of the area around Curiosity. In the immediate foregound is the rover's main deck, with the cylindrical, finned nuclear RTG at the back of it. Beyond this is the "Namib" dune, with a taller dune beyond it. The view was constructed froma series of images taken by the rover's Mastcam on December 18th, 2015 (Sol 1,197 on Mars), all of which have been white-balanced to present the view under normal Earth daylight conditions
This rather odd-looking image is a foreshortened 360-degree view of the area around Curiosity. In the immediate foreground is the rover’s main deck, with the cylindrical, finned nuclear RTG at the back of it. Beyond this is the “Namib” dune, with a taller dune beyond it. The view was constructed from a series of images taken by the rover’s Mastcam on December 18th, 2015 (Sol 1,197 on Mars), all of which have been white-balanced to present the view under normal Earth daylight conditions

Back to Sea for SpaceX

SpaceX, the private space launch company, is keeping itself busy. Following the successful launch of the Orbcomm mission from Florida’s Cape Canaveral Air force Station, together with the successful recovery of the first stage of the booster when it flew back to the Cape and performed a flawless vertical landing, the company’s next launch is scheduled for Sunday, January 17th.

The launch will take place from Vandenberg Air force Base, California, which is the company’s Pacific Coast launch operations centre. The primary aim of the mission is to place the third in a series of joint U.S.-European satellites into a near-polar orbit (for which Vandenberg AFB is ideally suited, as a polar launch from there does not pass over inhabited land during ascent, lessening the risk to human lives should a launch vehicle suffer a failure).

The Jason-3 series of missions is part of a very long-term series of studies (started in 1992) to study the topography of the ocean surface (i.e. the formation and movement of waves and the troughs between them), which can provide scientists with critical information about circulation patterns in the ocean, and about both global and regional changes in sea level and the climate implications of a warming world.

Jason-3, the latest in a series of joint US-European satellites studying the topography of the ocean's surface, is due for launch on December 17th, 2016, using a SpaceX Falcon 9 1.1 rocket
Jason-3, the latest in a series of joint US-European satellites studying the topography of the ocean’s surface, is due for launch on December 17th, 2016, using a SpaceX Falcon 9 1.1 rocket (image: NASA / CNES)

The polar orbit used for this kind of earth-observing mission, being almost perpendicular to the Earth’s rotation, allows the spacecraft to at some point travel over almost every part of the world’s oceans, vastly increasing its ability to gather data when compared to a vehicle in an equatorial orbit.

What is also significant about the mission is that it will use a SpaceX Falcon 9 1.1 booster, the first stage of which will once again attempt to return to Earth and make a safe landing. However, unlike the December 2015, this landing will once again be at sea, using a SpaceX droneship landing platform.

Continue reading “Space Sunday: dunes, rockets and asteroids”

Space Sunday: cosmic lightsabers, monkeys to Mars and junk in orbit

There were many remarkable space images published throughout 2015. However, perhaps one of the most memorable came at the end of the year, and coincided  with the release of Disney’s Star Wars: The Force Awakens. Captured by the Hubble Space Telescope, the image was immediately dubbed by the media as the “cosmic lightsaber” due to the manner in which part of the image resembles the double-sided lightsaber used by Darth Maul in an earlier Star Wars film.

It shows a new-born star laying within a cloud of dust, which is shooting out two beams of light from its poles and which seem to cut through the surrounding material and space.

Two beams of light slice through space from the polar regions of a new-born star. Captured by the Hubble Space Telescope, the image was immediately dubbed "the cosmic lightsaber" (image: ESA / NASA / D. Padgett / T. Megeath / B. Reipurth) - click for full size
Two beams of light slice through space from the polar regions of a new-born star. Captured by the Hubble Space Telescope, the image was immediately dubbed “the cosmic lightsaber” (image: ESA / NASA / D. Padgett / T. Megeath / B. Reipurth) – click for full size

The beams are no optical illusion, but the result of material from the surrounding dust cloud falling into the star, only to erupt into supersonic jets of material ejected up through the star’s poles and into space. As the jets travel outwards, so they encounter other dust and material, and distinctive arced shock waves form within the “beams”, which gradually give rise to knotted clumps of material called Herbig-Haro (HH) objects, and are ubiquitous in star-forming regions, although they are relatively short-lived in astronomical terms.

Given the nature of the HH object seen by Hubble (officially designated HH24), it is thought that the star causing it is very young – just a few thousand years old. It lies in a “stellar nursery” some 1,350 light-years away “in” the constellation of Orion, and which has one of the highest concentrations of HH objects yet found in our galaxy.

Another view of the "stellar nursery" where stars are being formed, captured by Hubble. HH24 can be seen at the top left, with further HH objects just visible in the lower right. Both this image and the one above were captured in infrared, allowing Hubble to "look through" the intervening clouds of dust and "see" the jets
Another view of the “stellar nursery” where stars are being formed, captured by Hubble. HH24 can be seen at the top left, with further HH objects just visible in the lower right. Both this image and the one above were captured in infra-red, allowing Hubble to “look through” the intervening clouds of dust and “see” the jets

Monkeys to Mars?

There is a mounting effort to see humans set foot on Mars some time within the next 25 years; however, Russia is apparently set on getting “crew” to Mars by 2017, in the form of four macaque monkeys.

The simians have been selected on the basis of their cognitive and learning abilities, and have been undergoing 3 hours a day of training for a possible flight to Mars, with news of the proposal first reaching the public domain in October 2015. The training is has been taking place at the Institute of Biomedical Problems in Moscow, and initially comprised training the monkeys to operate a joystick system to “shoot” targets on a screen, as indicated by a cursor.  Successful “hits” saw the monkeys rewarded with a sip of juice.

This has been followed by training the monkeys to solve simple puzzles and mathematical problems. “What we are trying to do,”  Inessa Kozlovskaya, responsible for the team training the monkeys, “is to make them as intelligent as possible so we can use them to explore space beyond our orbit,”

The Russian plan is to send the monkeys on a six-month voyage to Mars, during which their heath and ability to function during a prolonged stay in zero gravity conditions will be assessed, together with their exposure to cosmic radiation. However, Russian officials have refused to indicate whether the mission will include a return trip to Earth.

Rhesus macaques are one of the least endangered, most familiar of the "old world" monkeys, and are known for their intelligence and their social bonds (image: "carcoalfeather", deviant art)
Rhesus macaques are one of the least endangered, most familiar of the “old world” monkeys, and are known for their intelligence and their social bonds (image: “carcoalfeather”, deviant art)

Sending animals into space isn’t new. The very first animal to enter space was in fact a rhesus macaque called Albert. He flew a short-duration ballistic flight atop a US V2  in 1948, but died of suffocation mid-flight. His successors were no less fortunate. Alberts II, and IV were killed on impact when their capsule parachutes failed to deploy, and Albert III died when his V2 exploded on the edge of space.

Continue reading “Space Sunday: cosmic lightsabers, monkeys to Mars and junk in orbit”

Space Sunday: bringing a rocket home; uncovering Ceres

A second from touchdown: the Falcon 9 first stage booster, with landing legs deployed, about to make a successful landing at "Landing Zone 1", Cape Canaveral Air Force Station, having been launched from the space facility 10 minutes earlier as a part of a flight to deploy 11 Orbcomm telecommunications satellites
A second from touchdown: the Falcon 9 first stage booster, with landing legs deployed, about to make a successful landing at “Landing Zone 1”, Cape Canaveral Air Force Station, having been launched from the space facility 10 minutes earlier as a part of a flight to deploy 11 Orbcomm telecommunications satellites

On Monday, December 21st, the private space launch company SpaceX achieved a remarkable first in the annals of space flight: they successfully launched a payload carrying rocket into orbit, and then returned its first stage to a safe landing back on Earth, close to its original launch point.

The Falcon 9 rocket, in its first launch since June 2015 when a fuel tank failure lead to the vehicle’s destruction together with the Dragon resupply vehicle it was lifting to the International Space Station, was lifting a total of 11 communications satellites into orbit on behalf of Orbcomm.

The booster lifted-off from Florida’s Cape Canaveral Air Force Station at 20:29 EST on Monday, December 21st (01:29 UTC, Tuesday December 22nd).  At 2 minutes 27 seconds into the flight, having pushed the vehicle through the densest part of the atmosphere, the first stage engines shut down, and shortly afterwards, the first and second stages separated, allowing the latter’s Merlin engine to ignite.

As the second stage continued to accelerate up to deployment orbit, the first stage coasted upwards before using cold gas thrusters to effectively “flip” the booster around so it could use the first in a series of “boostback burns” of its main engines to slow itself down as well as pushing it back towards Cape Canaveral.

With this completed, the booster used the cold gas thrusters to again flip itself over so it would be descending engines first towards the ground, performing two further “boostback burns” to control its descent before making a final engine burn during the last few dozen metres of the descent and deploying its 4 landing legs and steering vanes for a successful touch down some 10 minutes after lift-off, which was captured by cameras on the ground and aboard an observing helicopter.

The SpaceX success came less than a month after Blue Origin, the private space company founded by Amazon billionaire Jeff Bezos, also landed the initial stage of their New Shephard launch system following a test launch. However, the latter is not intended to achieve orbital velocities at present, and so the booster stage – referred to as the “propulsion module” by Blue Origin – was not travelling nearly as fast as the Falcon 9 first stage, nor did it have to perform the complex “boostback” manoeuvres.

In the meantime, the second stage continued upwards, successfully deploying the Orbcomm satellites into LEO – low Earth orbit, at around 630 kilometres (just under 400 miles) altitude. With this part of the mission completed, the second stage booster also re-ignited its main engine, allowing it to achieve a geostationary transfer orbit and coast phase.

This was as important as the first stage landing because, while existing Falcon 9 rockets are capable of placing large payloads into geosynchronous equatorial orbit, some 36,000 km (22,000 miles) above the surface of the Earth, it has required the first stage of the rocket to do much more of the work, leaving it with insufficient fuel reserves to attempt a return to Earth and landing. The uprated second stage, tested as a part of this flight, alleviates the first stage of some of the booster phase work, allowing it to retain the fuel it needs to make a successful return to Earth.

The overall hope with the upgraded Falcon 9 and the new landing facilities at Cape Canaveral, is that they will allow SpaceX to lower launch costs to the benefit of customers, and allow them to make more efficient use of their boosters rather than just tossing them away into the Atlantic or Pacific after a single use.

However, even with this first successful landing, the company still has some significant hurdles to clear. One of these will be demonstrating it can refurbish used first stages at a fast enough pace to be able to maintain a launch cadence high enough to be attractive to commercial operators looking for launch opportunities, rather than risking them look to those companies able to offer a faster launch rate.

Nevertheless, SpaceX’s achievement is clear, and after the disappointments in trying to recover the Falcon 9 first stage at sea (initially seen as a “safer” option due to the negligible risk of civilian injuries if anything went wrong when compared to  returning a rocket to Earth near populated areas), deserves every congratulation.

Dawn over Ceres

Dawn mission patch (NASA / JPL)
Dawn mission patch (NASA / JPL)

Dawn, the NASA / ESA joint mission currently mapping Ceres, one of the solar system’s three “protoplanets” located in the asteroid belt between the orbits of Mars and Jupiter, reached its lowest planned orbital altitude in early December, ready to start the final phase of its mission.

The new orbit, just 385 km (230 miles) above Ceres mains the craft can image the surface at a resolution of 35 metres (120 feet) per pixel.

Of particular interest to the science team has been determining the mysterious bright patches seen within the crater Occator during Dawn’s approach to Ceres and during its higher mapping orbits. While perhaps the largest found, the bright spots in Occator are not alone – around 130 bright spots have been located, almost all of them within Ceres’ craters, and analysis now shows that the material  seems to be consistent with salts, such as sulfates, with silicate materials also very likely present.

A false-colour representation Occator Crater on Ceres reveals the short wavelength of the bright deposits in the crater, pointing to them being salts. Occator measures about 90 km (60 miles) across
A false-colour representation Occator Crater on Ceres reveals the short wavelength of the bright deposits in the crater, pointing to them being salts. Occator measures about 90 km (60 miles) across

Continue reading “Space Sunday: bringing a rocket home; uncovering Ceres”