Below are notable space developments that took place during 2015. Like last year, this list is broken down into quarters.
The list largely focuses on milestones in space flight and space science. A few other developmental milestones are sprinkled in so that future flights can be put into context. In addition, some general undercurrents of space science that permeated the year are listed at the bottom. A few space-related events with deep impressions in popular culture as also added this time.
[Updates: Dec 31 – Q4 add DAMPE.]
- Jan 6 – Kepler-438b was announced as a confirmed exoplanet. It is about 470 light-years away, in the constellation Lyra, and the most Earth-like exoplanet known to date.
- Jan 10 – After doing its part in the CRS-5 mission to the ISS, a Falcon 9 first stage made an unsuccessful landing attempt. Its target was an autonomous spaceport drone ship (ASDS), known as “Just Read the Instructions”, but cut too close on its open loop hydraulic fluid. [ More at Parabolic Arc ]
- Jan 16 – Elon Musk announced in Seattle that SpaceX would launch a new satellite Internet initiative.
- Jan 25 – Milestone prizes for the Google Lunar X Prize were awarded to: Astrobotic, Moon Express, Team Indus, Part Time Scientists, and Hakuto.
- Jan 31 – The Soil Moisture Active Passive (SMAP) satellite was launched by a Delta 2 rocket. SMAP measures moisture in the top layer of soil around the world, which is where the food we eat grows.
- Feb 11 – The DSCOVR spacecraft was launched. It will monitor solar wind from Sun-Earth L1, about 1.5 million km above Earth.
- Feb 27 – Leonard Nimoy, who played Spock in the original Star Trek series, died at age 83. His last tweet: “”A life is like a garden. Perfect moments can be had, but not preserved, except in memory. LLAP” (The last four letters stand for “live long and prosper”.)
- Mar 1 – A SpaceX Falcon 9 launched a pair of all-electric communication satellites to geosynchronous transfer orbit (GTO). Built by Boeing, the ABS 3A and EUTELSAT 115 West B satellites have no liquid propellants.
- Mar 3 – An electrical short caused Curiosity’s robotic arm to stop working. The likely cause several days later was an intermittent short in the percussion mechanism of the drill. It was working again on Mar 12.
- Mar 6 – The Dawn spacecraft began orbiting Ceres. Among the mysteries is a series of unusual bright spots on its surface.
- Mar 27 – Astronaut Scott Kelly and cosmonaut Mikhail Kornienko began a one-year trip in low Earth orbit to study the effects of prolonged zero-G space flight on the human body. As a bonus, Scott’s twin, Mark Kelly, will be studied concurrently on the ground.
- Apr 13 – ULA introduced its new Vulcan rocket. It will recover the first stage Blue Origin BE-4 main engines by using hypersonic decelerator, then parachute, then parafoil, then helicopter. [ More at Parabolic Arc ]
- Apr 14 – SpaceX flew its CRS-6 mission to the ISS, and attempted to land the first stage on the autonomous drone ship “Just Read the Instructions”. The stage touched down almost vertically, but had too much rotation to overcome, and ultimately fell over. [ YouTube video ]
- Apr 24 – Hubble celebrated its 25th anniversary in space. Launched in 1990, it was found to have blurry vision, which was corrected on the first astronaut serving mission in 1993. Four subsequent missions (1997, 1999, 2002, 2009) have improved instruments or replaced defective ones. The telescope continues to be in high demand. [ More at Hubble 25th ]
- Apr 29 – Blue Origin conducted its first developmental flight of its New Shepard spacecraft. The uncrewed went up to 93.5 km and reached Mach 3. [ YouTube video ]
- Apr 29 – A Russian Progress cargo ship bound for the ISS started to spin after separating from the third stage of a Soyuz launch vehicle. In spite of attempts to regain control, the ship was lost, and re-entered many days later. The next re-supply mission would be the SpaceX Falcon9 CRS-7 mission in June.
- Apr 30 – MESSENGER ended its mission by crashing into the surface of Mercury. It arrive at Mercury on Mar 18, 2011.
- May 6 – A SpaceX Crew Dragon successfully completed its pad abort test. The SuperDraco engines of the capsule yanked it and the Dragon trunk off the launch pad before jettisoning the trunk and deploying its chute. [ YouTube video ]
- May 14 – Singer Sarah Brighten postponed her trip to the ISS for “personal family reasons.”
- May 20 – An Atlas V launched the X-37B space plane and 10 CubeSats into orbit. One of the CubeSats was LightSail-A.
- May 26 – The Leonardo Permanent Multipurpose Module (PMM) of the ISS was moved from the Unity node to the Tranquilly node’s forward port. The PMM has a mass of about 10,000 kg (22,000 lbm).
- Jun 7 – The Planetary Society’s LightSail-A successfully unfurled its solar sail. Measuring 32 m2 in area, the sail was packed into a 3U CubeSat, along with electronics and deployment mechanisms. [ More at Planetary Society ]
- Jun 8 – DSCOVR reached its intended orbit, a Lissajous orbit at Sun-Earth L1.
- Jun 8 – NASA’s Low-Density Supersonic Decelerator (LSDS) completed its second flight test when in splashed down off the coast of Hawaii. It was lofted by balloon to 120,000 feet, then rocketed to 180,000 feet, before descending and braking at Mach 3.
- Jun 10 – A thruster on a Soyuz spacecraft unexpectedly fired during a test, causing the ISS to move. It was quickly brought under control by other thrusters on the Russian section of the ISS.
- Jun 14 – Contact was re-established with the Philae lander on Comet 67P/Churyumov-Gerasimenko as its solar panels got enough sunlight to power it again. Philae used Rosetta as a relay to transmit its data to Earth.
- Jun 17 – UrtheCast released samples of live HD video of the Earth, including traffic in Boston and a moving vessels on the Thames.
- Jun 28 – A SpaceX Falcon 9 failed during CRS-7 mission launch. While first stage was still firing, 139 seconds into flight, the second stage LOX tank ruptured. A failed strut letting loose a helium tank was the likely cause. The first stage continued to fire for several seconds. The Dragon capsule continued to transmit telemetry, but was not programmed to deploy chutes in this sort of emergency. Planet Labs lost another 8 Dove satellites; it has lost 28 in the Orbital Antares failed launch of Oct 2014.
- Jul 9 – The last communication from the Philae lander was received. Attempts to give it new instructions were unsuccessful.
- Jul 14 – New Horizons made its closest approach of Pluto, which showed itself to be geologically active.[ APOD photo; taken on approach ]
- Jul 16 – DSCOVR, in the Sun-Earth L1 neighborhood, captured the Moon transiting in front of the Earth, with a clear view of the lunar “far side”. NASA released the collected images on Aug 5. [ YouTube video ]
- Jul 23 – NASA announced discovery of Kepler-452b, the first potentially rocky super-Earth in the habitable zone of a Sun-like star, and the six-most Earth-like exoplanet known to date.
- Aug 8 – Astronauts ate food grown on the ISS for the first time.
- Aug 12 – Mars Reconnaissance Orbiter has now spent 10 years in orbit around Mars.
- Aug 12 – Comet 67P/Churyumov-Gerasimenko reached perihelion as the Rosetta spacecraft orbiting it collected new data.
- Aug 19 – The Japanese resupply mission Kounotori 5 (aka HTV-5) was launched to the ISS. It carried 6,000 kg of cargo, including CubeSats (14 Planet Labs “Doves” of Flock-2b, SERPENS, S-CUBE, AAUSAT5, and GOMX-3).
- Sep 9 – Five teams passed the first “ground tournament” of the NASA Cube Quest challenge; 13 teams presented initial spacecraft designs in August. There will be three more increasingly difficult tournaments, leading to selection as secondary payloads on the SLS EM-1 mission in 2018.
- Sep 13 – The Solar and Heliospheric Observatory (SOHO), a joint project of NASA and ESA, imaged its 3,000th comet.
- Sep 28 – NASA announced evidence of liquid water flowing on Mars.
- Oct 2 – The movie The Martian was officially released to theaters. Engineer and botanist Mark Watney has to use his wits to survive being stranded on Mars. NASA mostly gave thumbs up to the movie, but also took to it as a teachable moment about Martain dust storms.
- Oct 7 – SpaceIL said it has signed a contract with SpaceX to launch its lunar lander on a Falcon 9 in the second half of 2017 from Vandenberg AFB.
- Oct 14 – NASA awarded Venture Class Launch Services (VCLS) contracts to three companies to launch microsatellites and nanosatellites (including CubeSats) into orbit. The three companies are: Firefly Space Systems, Rocket Lab USA, and Virgin Galactic.
- Oct 21 – The NASA Kepler spacecraft, repurposed for the K2 mission, has discovered a miniature planet being ripped apart as it spirals around a dying star. The planetesimal is the size of a large asteroid, and orbits white dwarf WD 1145+017 once every 4.5 hours.
- Oct 28 – Cassini flew 49 km above the surface of Enceladus, the closest fly-by of the mission. It is choreographed to sample the plumes of the geysers near the moon’s south pole.
- Oct 28 – NOAA officially took control of the DSCOVR spacecraft from NASA.
- Nov 4 – The experimental Super Strypi (formerly LEONIDAS) failed its first launch. It was intended to put 12 CubeSats and Hawaii’s HiakaSat into orbit.
- Nov 5 – New Horizons completed the last of four engine burns to direct it at 2014 MU69, a small body more than 1 billion miles beyond Pluto. It will arrive in Jan 2019.
- Nov 12 – NASA announced the first discovery of a gamma-ray pulsar in another galaxy. The NASA Fermi Gamma-ray Space Telescope found the pulsar on the outskirts of the Tarantula Nebula in the Large Magellanic Cloud, about 163,000 light-years away.
- Nov 23 – New Shepard reached 100 km. Both capsule and rocket achieved soft landing. Named for astronaut Alan Shepard, the capsule landed using parachutes 11 minutes later. The rocket fired its engines, setting down on its launch pad at about 2.0 meters/sec. [ YouTube video ]
- Dec 3 – NASA reported that the Hubble and Spitzer space telescopes have spotted a galaxy from 13.8 billion years ago, 400 million years after the Big Bang. The galaxy, nicknamed “Tayna” (first-born) This was only possible because of gravitational lensing by the galactic cluster MACS0416.1-2403.
- Dec 3 – A pair 2 kg cubes – one gold, one platinum – were part of the LISA Pathfinder spacecraft, launched by a Vega rocket from French Guiana. It should reach its destination, a halo orbit around Sun-Earth L1, around the end of Jan 2016. It is testing technologies for an eventual Evolved Laser Interferometer Space Antenna (eLISA), which would be the first space-based gravitational wave detector, to be launched in 2034. It was 100 years earlier, in December 1915, that Einstein published his General Theory of Relativity.
- Dec 6 – An Orbital-ATK Cygnus capsule was launched by a ULA Atlas V, and docked with the ISS on Dec 9. It was carrying over 3,000 kg of supplies, experiments, station hardware.
- Dec 9 – The JAXA Akasuki probe entered orbit around Venus, at an altitude of 440,000 km, five years after main engine failure on Dec 6, 2010. This time, it used four small thrusters. The spacecraft is imaging from a equatorial orbit, in contrast to ESA Venus Express, which was in a polar orbit, and ended its mission in Dec 2014.
- Dec 16 – India launched six Singaporean satellites on its PSLV-CA vehicle. The launch also tested the rocket’s fourth state restart capability, 17 minutes after cut-off.
- Dec 16 – China launched its DArk Matter Particle Explorer (DAMPE), also known as Wukong (Monkey King), after a character from ancient Chinese literature. The spacecraft also carries instruments from Switzerland and Italy.
- Dec 21 – The Falcon 9 returned to flight. This time, it launched 11 ORBCOMM satellites. The propellants were densified fuels by supercooling. Following an engine relight to reverse direction and hypersonic reentry, the first stage returned to land at Cape Canaveral. [ YouTube video ]
- Dec 30 – Oak Ridge National Laboratory (ORNL) has produced 50 grams of plutonium-238 (Pu-238), the first demonstration of the capability in the US since the late 1980s. The NASA Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) requires 4.8 kg of Pu-238 to produce about 120 watts of power.
Space science undercurrents
Perhaps the biggest lesson of the year was that the solar system is potentially a very wet place. Water seems to be pervasive, whether it be in liquid or solid form.
- The Moon: New results are still coming from Lunar Reconnaissance Orbiter (LRO). The Earth’s gravitational pull is opening up faults in the lunar crust. While tidal forces have been known for a while, but it was a surprise to find that the Earth is still helping to shape the Moon. China reported that instruments on Yutu (“Jade Rabbit“) rover were still functioning, although the rover itself has long been stationary. In March, data from Yutu pointed to a new type of mare basalt that differs from samples found on the US Apollo and Soviet Luna missions of 40 years ago.
- Mercury: MESSENGER ended its mission around Mercury in April. During its time there, it mapped the entire planet and found water ice at Mercury’s north pole. After the mission ended, it was reported that Mercury once had a magnetic field that may have been as strong as Earth’s.
- Mars: An armada of orbiters and rovers continues to study Mars. In April, it was reported that Curiosity detected perchlorates, which dramatically decrease the freezing point of water. In fact, during winter and spring on Mars, the water could be liquid. In September, NASA announced that evidence of liquid water flowing on Mars. The first evidence goes back to 2010, using data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), which is on-board the Mars Reconnaissance Orbiter. In November, NASA announced that solar storm likely stripped away the atmosphere of Mars. This finding comes from the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission.
- Ceres: With Dawn at Ceres, the biggest mystery is perhaps a bright spot, which at closer resolution is a series of bright spots. The otherwise flat dwarf planet also showed a conical mountain that is 6 km high.
- Europa: The geysers that Hubble saw in 2013 have not been seen since. In May this year, NASA reported that dark material on Europa’s surface might be sea salt exposed to radiation. Lab experiments on Earth show similar spectra.
- Ganymede: Jupiter’s largest moon may have more water beneath its surface than Earth has on its surface. This latest finding, announced in March, is based on Hubble data, but was hinted at by the Galileo spacecraft in the 1990s.
- Enceladus: Based on data from Cassini, a global ocean below the surface is now thought to feed the geysers.
- Pluto: New Horizons surprised everyone with a geologically active Pluto that also has a multi-layered hazy atmosphere. Because of its distance from Earth data continues from the encounter continues to stream back to Earth is it heads for its next destination, 2014 MU69. Pluto has a surprising range of subtle colors, with many landforms having their own distinct colors. In November, researchers studying New Horizons data reported on “what appear to be ice-spewing volcanoes on the surface of Pluto.”
- Comet 67P/Churyumov-Gerasimenko: Rosetta and Philae studied the comet as it reached perihelion. In its bumping landing, Philae picked up more samples of organics than it would otherwise. It picked up 16 organic compounds, of which 4 had never been seen in a comet before.