1.Asteroid ‘99942 Apophis’
- On April 13, 2029, a near-Earth asteroid will cruise by Earth, about 31,000 km above the surface.
- The asteroid, called 99942 Apophis, is 340 m wide.
- At one point, it will travel more than the width of the full Moon within a minute and it will get as bright as the stars in the Little Dipper, according to NASA’s Jet Propulsion Laboratory.
- It is rare for an asteroid this size to pass by Earth so close.
- Although scientists have spotted small asteroids, on the order of 5-10 metres, flying by Earth at a similar distance, asteroids the size of Apophis are far fewer in number and so do not pass this close to Earth as often.
- Among potential lessons from Apophis, scientists are hoping they can use its flyby to learn about an asteroid’s interior.
- Apophis is one of about 2,000 currently known Potentially Hazardous Asteroids, and scientists also hope their observations might help gain important scientific knowledge that could one day be used for planetary defence.
2. Saturn’s moon Titan has 100-m deep methane lakes
- Saturn’s largest moon Titan has small liquid lakes that run more than 100 metres deep, perched atop hills and filled with methane, scientists have found using data from NASA’s Cassini spacecraft.
Methane Rains on Saturn
- Scientists have known that Titan’s hydrologic cycle works similarly to Earth’s — with one major difference. Instead of water evaporating from seas, forming clouds and rain, Titan does it all with methane and ethane.
- We tend to think of these hydrocarbons as a gas on Earth, unless they’re pressurized in a tank.
- However, Titan is so cold that they behave as liquids, like gasoline at room temperature on our planet.
3. Stephen Hawking’s hypothesis on black holes discarded
- An international research team including researchers from IUCAA, Pune has ruled out the possibility of primordial black holes being a major constituent of dark matter.
- This finding disproves a theoretical claim of Prof Stephen Hawking.
What is Dark matter?
- In the solar system, Mercury, the planet closest to the Sun, takes just 88 days to make one revolution around the sun, while Neptune, the farthest one, takes 165 years to make one round.
- In like manner, laws of gravity expect us to see stars closer to the centre of galaxies rotating faster than the stars on the edge.
- However, in most galaxies, the stars closer to the centre and the stars at the edge of the galaxies take almost same time to make one revolution.
- This implied that something invisible and enveloping the galaxies was giving an extra push to the outer stars, speeding them up.
- This entity has remained as one of the central unresolved puzzles in cosmology since 1930s. It is, no wonder, named `Dark Matter’.
4. GRAPES-3 Experiment
- For the first time in the world, researchers at the GRAPES-3 muon telescope facility in Ooty have measured the electrical potential, size and height of a thundercloud that passed overhead on December 1, 2014.
- GRAPES-3 (Gamma Ray Astronomy PeV EnergieS phase-3) is designed to study cosmic rays with an array of air shower detectors and a large area muon detector.
- It aims to probe acceleration of cosmic rays in the following four astrophysical settings.
- It is located at Ooty in India and started as a collaboration of the Tata Institute of Fundamental Research, Mumbai, India and the Osaka City University, Osaka, Japan.
5. Atmospheric Waves Experiment (AWE)
- NASA has selected a $42 million mission that will help scientists understand and, ultimately, forecast the vast space weather system around our planet.
Atmospheric Waves Experiment (AWE) mission
- AWE is a Mission of Opportunity under NASA’s Heliophysics Explorers Program, which conducts focused scientific research and develops instrumentation to fill the scientific gaps between the agency’s larger missions.
- The AWE mission will cost $42 million and is planned to launch in August 2022, attached to the exterior of the Earth-orbiting International Space Station (ISS).
- The new experiment will obtain global observations of an important driver of space weather in a dynamic region of Earth’s upper atmosphere that can cause interference with radio and GPS communications.
- The AWE will focus on colourful bands of light in Earth’s atmosphere, called airglow, to determine what combination of forces drive space weather in the upper atmosphere.
6. How the Moon got ‘sunburns’: A result of sheer magnetism
- The Moon has visible ‘sunburns’, or distinctive patterns of swirls on its surface.
- NASA has now analysed data to show that these are a result of interactions between the Sun’s damaging radiation with pockets of lunar magnetic field.
Sunburns on Moon
- Every object, planet or person travelling through space has to contend with the Sun’s damaging radiation.
- Research using data from NASA’s ARTEMIS mission suggests how the solar wind and the Moon’s crustal magnetic fields work together to give the Moon a distinctive pattern of darker and lighter swirls.
- The Sun releases a continuous outflow of particles and radiation called the solar wind.
- Because the solar wind is magnetised, Earth’s natural magnetic field deflects the solar wind particles so that only a small fraction of them reach the planet’s atmosphere.
- But the Moon has no global magnetic field; magnetised rocks near the lunar surface do create small, localised spots of magnetic field.
7. NASA’s Opportunity Rover
- NASA has announced the end of the Opportunity rover’s mission.
- Opportunity rolled out on to the Martian surface in 2004, 20 days after its twin, Spirit, had landed on the other side of the Red Planet.
- Over the next 14 years, it got successes that made it one of the most overachieving explorer robots ever built.
Spirit and Opportunity Rovers
- Spirit and Opportunity were identical, golf-cart-sized, solar-powered rovers.
- Spirit landed at Gusev Crater; Opportunity followed, landing on the opposite side of Mars at Meridiani Planum.
- Contact with Spirit was lost in March 2010, and the mission was declared over in May, 2011.
- Opportunity worked on Mars for over 14 years, longer than any other robot. Both rovers were originally supposed to have only 90-day missions.
- Opportunity travelled 45.16 km on the surface of Mars, more than any other rover.
- Its equipment have been compromised by the storm, which struck while the rover was at a site called Perseverance Valley.
8. Ultima Thule: Farthest object ever visited, what secrets does it hold?
- Recently NASA’s New Horizons spacecraft carried out a historic flyby of a distant object called Ultima Thule followed by beaming back of the first images.
- It is the most distant object ever visited, which is one of the reasons that make the mission special.
- Officially named (486958) 2014 MU69, it earned the nickname Ultima Thule following a public contest in 2018.
- It is located in the Kuiper Belt, a disc in the outer Solar System (beyond Neptune) that consists of small bodies including Pluto.
- 2014 MU69 was discovered in June 2014 by astronomers using the Hubble Space Telescope but is so distant that many of its characteristics remain to be understood.
9. China’s Chang’e-4 lunar rover lands on moon’s far side
- China’s Chang’e-4 lunar rover scripted history when it made the first-ever soft landing on the far side of the moon.
- Chang’e-4 named after a Chinese moon goddess and comprising a lander and a rover, touched down at the preselected landing area at 177.6 degrees east longitude and 45.5 degrees south latitude on the far side of the moon.
- The lunar explorer landed on the far side of the moon and has already sent back its first pictures from the surface.
- The pioneering achievement is another demonstration of China’s ambitions to be a space power.
- The robotic spacecraft is carrying instruments to analyse the unexplored region’s geology and will conduct biological experiments.
- The probe was launched by a Long March-3B carrier rocket on December 8 from the Xichang Satellite Launch Centre in Sichuan Province.
- It landed on the Von Karman crater in the South Pole-Aitken basin and then sent back a picture of the landing site shot by one of the monitor cameras on the probe’s lander, marking the world’s first image taken on the moon’s far side.
- The scientific tasks of the Chang’e-4 mission include low-frequency radio astronomical observation, surveying the terrain and landforms, detecting the mineral composition and shallow lunar surface structure, and measuring the neutron radiation and neutral atoms to study the environment on the far side of the moon.
10. China’s BeiDou navigation satellite, rival to US GPS, starts global services
- China’s BeiDou Navigation Satellite System (BDS), touted as a rival to the widely-used American GPS, has started providing global services.
BeiDou Navigation Satellite System (BDS)
- Named after the Chinese term for the ‘Big Dipper’, the BeiDou system started serving China in 2000 and the Asia-Pacific region in 2012.
- It will be the fourth global satellite navigation system after the US GPS, Russia’s GLONASS and the European Union’s Galileo.
- The positioning accuracy of the system has reached 10 metres globally and five metres in the Asia-Pacific region.
- Its velocity accuracy is 0.2 metres per second, while its timing accuracy stands at 20 nanoseconds, he said.
- Pakistan has become the first country to use the BeiDou system ending its reliance on the Global Positioning System (GPS).
11. China launches first satellite for the space-based broadband project
- China on December 22 launched its first communication satellite to provide broadband internet services worldwide in an apparent bid to rival Google and other international firms.
- The Hongyun project, started in September 2016, aims to build a space-based communications network to provide broadband internet connectivity to users around the world, especially those in the underserved regions.
- The satellite was launched from a Long March 11 carrier rocket from the Jiuquan Satellite Launch Centre in north-western China.
- It is the first in the Hongyun project planned by China Aerospace Science and Industry Corp (CASIC).
- The spacecraft is tasked with verifying basic designs of Hongyun satellite and demonstrating low-orbit broadband communications technologies.
12. NASA’s HiRISE photographs Mars InSight lander from space
- NASA has pinpointed the exact landing location of its newly launched InSight lander, using a powerful camera onboard another of the agency’s spacecraft, hovering around the Red Planet.
After InSight’s landing
- On November 26, InSight landed within a 130 km ellipse at Elysium Planitia on Mars.
- However, there was no way to determine exactly where it touched down within this region.
- InSight was set to study the interior of Mars, and will explore valuable science as NASA prepares to send astronauts to the Moon and later to Mars.
- The spacecraft will operate on the surface for one Martian year, plus 40 Martian days, or sols, until November 24, 2020.
- The HiRISE (which stands for High Resolution Imaging Science Experiment) aboard Mars Reconnaissance Orbiter (MRO) spotted Martian landscape and ground around the lander.
- It released three new features on the Martian landscape, which appear to be teal.
- However, it is not their actual colour, but light reflected off their surfaces caused the colour to be saturated.
- The ground around the lander appears dark, having been blasted by its retro-rockets during descent.
13. NASA’s ICESat-2 maps Antarctic ice sheet melting
- NASA’s ICESat-2 launched less than three months ago has mapped melting ice sheets in Antarctica and the resulting sea level rise across the globe, which could help improve climate forecasts.
- The ICESat-2 stands for Ice, Cloud and land Elevation Satellite-2 .
- It is measuring the height of sea ice to within an inch, tracing the terrain of previously unmapped Antarctic valleys, surveying remote ice sheets, and peering through forest canopies and shallow coastal waters.
- With each pass of the ICESat-2 satellite, the mission is adding to datasets tracking Earth’s rapidly changing ice.
- As ICESat-2 orbits over the Antarctic Ice Sheet, the photon returns reflect from the surface and show high ice plateaus, crevasses in the ice 20 metres deep, and the sharp edges of ice shelves dropping into the ocean.
14. Soyuz: first manned mission to ISS since October failure
Mission to ISS
- A Soyuz rocket carrying Russian, American and Canadian astronauts took off from Kazakhstan and reached orbit in the first manned mission since a failed launch in October.
- It was the first manned launch for the Soviet-era Soyuz when a rocket carrying astronauts failed just minutes after blast-off, forcing the pair to make an emergency landing.
- They escaped unharmed but the failed launch as first such incident in Russia’s post-Soviet history raised concerns about the state of the programme.
- The Soyuz is the only means of reaching the ISS since the U.S. retired the space shuttle in 2011.
15. NASA’s InSight spacecraft lands on red planet after six-month journey
Landing on the Red Planet
- InSight, a NASA spacecraft designed to burrow beneath the surface of Mars landed on the red after a six-month, 482 million-km journey and a perilous, six-minute descent through the rose-hued atmosphere.
- It was NASA’s ninth attempt to land at Mars since the 1976 Viking probes. All but one of the previous U.S. touchdowns was successful.
- NASA last landed on Mars in 2012 with the Curiosity rover.
- The plan called for the spacecraft to go from 12,300 mph (19,800 kph) to zero in six minutes flat as it pierced the Martian atmosphere and settled on the surface.
16. NASA’s Ralph and Lucy set to visit Jupiter’s Trojan asteroids in 2021
- NASA’s Ralph — a space instrument that has travelled as far as Pluto — is set to explore Jupiter’s Trojan asteroids, which are remnants from the early days of the solar system.
- Ralph was first launched aboard the New Horizons spacecraft in 2006 and obtained stunning flyby images of Jupiter and its moons.
- This was followed by a visit to Pluto where Ralph took the first high-definition pictures of the iconic minor planet.
- In 2021, Ralph is set to journey with the Lucy mission to Jupiter’s Trojan asteroids.
- The instrument will fly by another Kuiper Belt object called 2014 MU69 nicknamed Ultima Thule in January 2019.
- Ralph’s observations of 2014 MU69 will provide unique insights into this small, icy world.
Lucy and L’Ralph
- The Lucy spacecraft carries a near-twin of Ralph, called L’Ralph, which will investigate Jupiter’s Trojan asteroids.
- The L’Ralph instrument suite will study this diverse group of bodies.
- Lucy will fly by six Trojans and one Main Belt asteroid more than any other previous asteroid mission.
- L’Ralph will detect the Trojan asteroids’ chemical fingerprints.
- L’Ralph allows scientists to interpret data provided by the Sun’s reflected light that are the fingerprints of different elements and compounds.
- These data could provide clues about how organic molecules form in primitive bodies, a process that might also have led to the emergence of life on Earth.
17. Earth has two extra, hidden ‘moons’
Three Moons for Earth
- The existence of the two extra ‘moons’ was hotly debated for over 50 years but as per a recent National Geographic report, Hungarian astronomers and physicists have finally provided enough data to confirm.
- The moon has at least two other companions made entirely of dust.
- The team of researchers confirmed their presence through photographs of the natural bodies at a distance of approximately 250,000 miles more or less the same distance as our moon.
Facts about the newly discovered dust moons
- The presence of the dust ‘moons’ or Kordylewski Clouds had been inferred by researchers since long before
- The first glimpse of the clouds was seen only in 1961 by Polish astronomer Kazimierz Kordylewski, after whom the dust clouds were named
- The new findings note that each Kordylewski cloud is about 15 by 10 degrees wide, or equal to 30 by 20 lunar disks in the night sky
- They are spread over a space area that is almost nine times the width of Earth — about 65,000 by 45,000 miles in actual size
- The dust ‘moons’ are huge but they are made of tiny dust particles that barely measure one micrometre across.
18. Mission Mercury: How will twin probes reach there, and why?
- The European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) has successfully sent two probes on a joint mission to Mercury, the closest planet to the Sun.
- An Ariane 5 rocket, launched from French Guyana, lifted an unmanned spacecraft, BepiColombo, which is carrying the two probes.
- The spacecraft separated and went into orbit for the 7-year trip to Mercury.
Details of the Mission
- It is the first European mission to Mercury, and the first to send two spacecraft to make complementary measurements of the planet and its environment at the same time.
- The orbiters are ESA’s Mercury Planetary Orbiter (MPO) and JAXA’s Mercury Magnetospheric Orbiter (MMO, or ‘Mio’).
- The ESA-built Mercury Transfer Module (MTM) will carry the orbiters to Mercury using a combination of solar electric propulsion and gravity assist flybys.
19. Largest galaxy cluster in early universe found
- Astronomers have discovered the largest and most massive galaxy super cluster yet found in the early universe.
- It was formed just over two billion years after the Big Bang.
- The galaxy proto-supercluster, nicknamed Hyperion, was identified using the VIMOS instrument on European Southern Observatory’s (ESO) Very Large Telescope in Chile.
- Located in the constellation of Sextans, Hyperion was identified by a novel technique to analyse the vast amount of data obtained from the VIMOS Ultra-Deep Survey.
- Hyperion has a calculated mass more than one million billion times that of the Sun, making it the largest and most massive structure to be found so early in the formation of the universe.
- Surprisingly the galaxy was evolved in very less time when the universe was relatively young.
20. NASA probe to fly by most distant object ever visited by a spacecraft
Setting a New Record
- NASA’s New Horizons probe is on course to fly by the Kuiper Belt object nicknamed Ultima Thule, which is at a distance of 6.6 billion kilometers from Earth.
- This event will set the record for the most distant object ever visited by a spacecraft.
- The spacecraft has successfully performed the three and half-minute manoeuvre on October 3 to home in on its location.
- The manoeuvre slightly tweaked the spacecraft’s trajectory and bumped its speed by 2.1 metres per second keeping it on track to fly past Ultima officially named 2014 MU69 on January 1, 2019.
- This manoeuvre has led the farthest exploration in world more than a billion miles beyond Pluto.
Trajectory Correction Maneuver
- New Horizons itself was about 6.35 billion km from earth when it carried out trajectory correction maneuver (TCM), the farthest course-correction ever performed.
- This was the first Ultima targeting maneuver that used pictures taken by New Horizons itself to determine the spacecraft’s position relative to the Kuiper Belt object.
- The TCM is done by determining the current trajectories and its target, and then calculating the manoeuvering required to put the spacecraft at the desired aim point for the flyby 3,500 km from Ultima at closest approach.
21. Japan drops new robot on asteroid
- The Hayabusa2 probe launched the French-German Mobile Asteroid Surface Scout, or MASCOT towards the Ryugu asteroid’s surface.
- The 10-kg box-shaped MASCOT is loaded with sensors.
- It can take images at multiple wavelengths, investigate minerals with a microscope, gauge surface temperatures and measure magnetic fields.
- The MASCOT got separated from the spacecraft as planned and got safely landed
- A Japanese probe launched a new observation robot towards an asteroid as it pursues a mission to shed light on the origins of the solar system.
- The Hayabusa2 is scheduled later this month to deploy an “impactor” that will explode above the asteroid, shooting a two-kilo copper object into it to blast a small crater on the surface.
- The probe will then hovers over the artificial crater and collect samples using an extended arm.
22. Parker, the world’s first mission to Sun lifts off
Parker Solar Probe
- NASA launched the Parker Solar Probe – the space agency’s first mission to the sun – that will explore the sun’s atmosphere and its outermost atmosphere, the corona.
- The spacecraft is named after 91-year old solar physicist Eugene Parker, 91, who was the first scientist to describe solar wind in 1958.
- The probe, about the size of a car, will fly through the Sun’s atmosphere and will come as close as 3.8 million miles to the star’s surface, well within the orbit of Mercury.
- It will be more than seven times closer than any spacecraft has come before. The Parker probe is expected to make 24 loops of the Sun over seven years.
23. NASA’s newest planet hunter starts operations
Transiting Exoplanet Survey Satellite (TESS)
- After a successful launch in April this year, NASA’s newest planet hunter, the TESS has now started its search for planets around nearby stars.
- TESS is NASA’s latest satellite to search for planets outside our solar system, known as exoplanets.
- The mission will spend the next two years monitoring the nearest and brightest stars for periodic dips in their light.
- TESS is expected to transmit its first series of science data back to Earth in August, and thereafter periodically every 13.5 days, once per orbit, as the spacecraft makes it closest approach to Earth.
- These events, called transits, suggest that a planet may be passing in front of its star.
- TESS is expected to find thousands of planets using this method, some of which could potentially support life.
24. Nasa unveils program to defend Earth from asteroid attack
- The US and other nations have long sought to track “near-earth objects,” or NEOs, coordinating efforts through the International Asteroid Warning Network and the United Nations
- The Trump Administration now wants to enhance those efforts to detect and track potential planet killers and to develop more capable means to deflect any that appear to be on a collision course
- The government unveiled new goals this week for Nasa’s work on countering NEOs over the next decade
- Nasa has documented roughly 96% of the objects large enough to cause a global catastrophe since work began in 1998
- More than 300,000 objects larger than 40 meters (131 feet) wide orbit the sun as NEOs, according to Nasa estimates
- Many of these were difficult to detect more than a few days in advance
- Forty meters is about the average size an object must be to make it through the atmosphere without burning up
Double Asteroid Redirection Test (DART) mission
- The goal of this mission is to impact the smaller “moonlet” of a binary asteroid called Didymos, to learn how well we may be able to alter the course of a future killer rock
- It is expected to be complete by 2021-2022