My Science School

The dinosaur-killing crash threw huge amounts of debris into the air and caused massive tidal waves to wash over parts of the American continents. There is also evidence of substantial fires from that point in history.

For a long time it was thought that the non-bird dinosaurs died out 65 million years ago.

But Paul explains, 'The dating of those layers of clay around the world is very accurate - it's estimated to within a couple of thousands of years.

As originally proposed in 1980 by a team of scientists led by Luis Alvarez and his son Walter, it is now generally thought that the K–Pg extinction was caused by the impact of a massive comet or asteroid 10 to 15 km (6 to 9 mi) wide, 66 million years ago, which devastated the global environment, mainly through a lingering impact winter which halted photosynthesis in plants and plankton.

The blame can't solely rest on the asteroid. Prior to its crash landing, Earth was experiencing a period of climate change. This was making things harder for life on our planet.

In what is now central India, there was substantial volcanic activity that, although unrelated to the asteroid impact, was causing problems of its own. The resulting lava outcrop is now known as the Deccan Traps.

Paul says, 'For two million years there was a huge amount of volcanic activity going on, spewing gases into the atmosphere and having a major impact on global climate.

 

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China's Five-hundred-meter Aperture Spherical Radio Telescope, known as FAST, is the world's most sensitive listening device.  For the review to be successful, FAST must meet the specifications initially laid out in the proposed design in 2008, such as the telescope's sensitivity and performance. NAOC ran an internal review earlier this year, demonstrating that the telescope is as - if not more - sensitive as planned.

The construction of FAST, while solely funded by the Chinese government, involved collaboration with international organizations, including Australia's Commonwealth Scientific and Industrial Research Organization, but exactly who in the international community will be able to use FAST - and to what extent - is still to be decided. While both LI and JIANG stressed the importance of international collaboration (they have both conducted research using data from radio telescopes in Australia and in Puerto Rico), the decision lies with the Chinese government.

That work could include the detection of pulsars, for example. When a giant star collapses in on itself, it forms a dense neutron star that rotates, flashing a beam of intense radiation every so often. The beam is called a pulsar, and it can't be visually observed. However, because that flash is a radio signal, scientists can listen it for using a radio telescope like FAST. Once they detect a pulsar, they can use it to identify and measure the behavior of other physical phenomena, such as gravitational waves.

 

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With the Artemis program, NASA will land the first woman and next man on the Moon by 2024, using innovative technologies to explore more of the lunar surface than ever before. We will collaborate with our commercial and international partners and establish sustainable exploration by the end of the decade. Then, we will use what we learn on and around the Moon to take the next giant leap – sending astronauts to Mars.

NASA’s powerful new rocket, the Space Launch System (SLS), will send astronauts aboard the Orion spacecraft nearly a quarter million miles from Earth to lunar orbit. Astronauts will dock Orion at the Gateway and transfer to a human landing system for expeditions to the surface of the Moon. They will return to the orbital outpost to board Orion again before returning safely to Earth.

While Mars remains our horizon goal, we have set our sights first on exploring the entire surface of the Moon with human and robotic explorers. We will send astronauts to new locations, starting with the lunar South Pole.

The femininity of the name is a deliberate choice as well: The Apollo missions were crewed exclusively by men, though they relied on many women for their success. This time around things are different: Both women and men have now explored and set records in space, and no doubt those of other identifications will do so soon as well.

 

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Indian astronomers have discovered one of the farthest star galaxies in the universe! In a key achievement for the Indian space programme, a team of astronomers headed by Dr Kanak Saha, from Pune-based Inter-University Centre for Astronomy and Astrophysics (IUCAA), discovered a galaxy called AUDFs01. The information was shared by Union Minister Dr Jitendra Singh on Tuesday. He said that the first Multi-Wavelength Space Observatory by India, “AstroSat”, found the galaxy, which is located at a distance of 9.3 billion light years from the Earth, by detecting extreme UV light from it.

The statement said that the uniqueness of this feat was the AstroSat/UVIT detector’s background noise was much less than the detector placed on the US-based NASA’s Hubble Space Telescope.

The Indian Space Research Organisation (ISRO) had launched the AstroSat on September 29, 2015. The development of the country’s maiden space observatory had been undertaken by a team led by Shyam Tandon, a Professor at IUCAA, and the project had been supported by the Indian space agency.

 

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The Venera program was the name given to a series of space probes developed by the Soviet Union between 1961 and 1984 to gather information about the planet Venus. 

The probe was equipped with scientific instruments including a flux-gate magnetometer attached to the antenna boom, two ion traps to measure solar wind, micrometeorite detectors, and Geiger counter tubes and a sodium iodide scintillator for measurement of cosmic radiation. An experiment attached to one solar panel measured temperatures of experimental coatings. Infrared and/or ultraviolet radiometers may have been included. The dome contained a KDU-414 engine used for mid-course corrections. Temperature control was achieved by motorized thermal shutters.

During most of its flight, Venera 1 was spin stabilized. It was the first spacecraft designed to perform mid-course corrections, by entering a mode of 3-axis stabilization, fixing on the Sun and the star Canopus. Had it reached Venus, it would have entered another mode of 3-axis stabilization, fixing on the Sun and Earth, and using for the first time a parabolic antenna to relay data.

 

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The Lunar Reconnaissance Orbiter (LRO) was launched with the Lunar Crater Observation and Sensing Satellite (LCROSS) on the first U.S. mission to the Moon in over 10 years. Both were part of NASA’s now-canceled Lunar Precursor Robotic Program.

LRO’s primary goal was to make a 3D map of the Moon’s surface from lunar polar orbit as part of a high-resolution mapping program to identify landing sites and potential resources, to investigate the radiation environment, and to prove new technologies in anticipation of future automated and human missions to the surface of the Moon.

LRO gathered information on day-night temperature maps, contributed data for a global geodetic grid, and conducted high-resolution imaging. The spacecraft paid particular emphasis to the Moon’s Polar Regions where scientists suspected there might be water in the permanently shadowed areas. (In 2018 a team of scientists directly observed definitive evidence of water ice on the Moon’s surface. At the southern pole, most of the ice is concentrated at lunar craters, while the northern pole’s ice is more widely, but sparsely spread.)

 

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The carbon dioxide traps most of the heat from the Sun. The cloud layers also act as a blanket. The result is a “runaway greenhouse effect” that has caused the planet’s temperature to soar to 465°C, hot enough to melt lead. This means that Venus is even hotter than Mercury.

The surface of Venus has been mapped by radar. The maps show thousands of volcanoes and impact craters. There are two main upland areas, with a mountain range taller than Mt. Everest.

Dozens of spacecraft have visited Venus, but many mysteries remain. ESA’s Venus Express has been in near-polar orbit around the planet since it arrived in April 2006. Most of its instruments have been studying the dense atmosphere and rapidly moving clouds, or investigating how the Sun affects the planet. However, its infrared sensor has also been able to map some of the surface and show that active volcanoes may exist on Earth’s neighbour.

 

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The Moon is an average of 238,855 miles (384,400 km) away. How far away is that? That’s 30 Earths.

Why mention the average distance? Well, the Moon is not always the same distance away from Earth. The orbit is not a perfect circle.



When the Moon is the farthest away, it’s 252,088 miles away. That’s almost 32 Earths. When it's closest, the Moon is 225,623 miles away. That’s between 28 and 29 Earths.

Today, the moon is moving away from Earth at a rate of about 1.5 inches (4 cm) per year.

The moon is in synchronous rotation with Earth. In other words, the moon rotates on its axis in about the same amount of time it takes to revolve around Earth — 27 days 8 hours, which is called sidereal month. So we always see the same side of the moon; there is no "dark side of the moon." Instead, scientists refer to the side of the moon facing away from the planet as the "far side of the moon." The far side can be spotted by missions such as NASA's DSCOVR satellite, which captured a video of the moon "photobombing" Earth.

A lunar month, also called a synodic month, is the time it takes for the moon to complete a lunar cycle — full moon to full moon. A lunar month is about 29 days 13 hours.

 

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Something deadly might be wafting through the clouds shrouding Venus—a smelly, flammable gas called phosphine that annihilates life-forms reliant on oxygen for survival. Ironically, though, the scientists who today announced sightings of this noxious gas in the Venusian atmosphere say it could be tantalizing—if controversial—evidence of life on the planet next door.

As far as we know, on rocky planets such as Venus and Earth, phosphine can only be made by life—whether human or microbe. Used as a chemical weapon during World War I, phosphine is still manufactured as an agricultural fumigant, is used in the semiconductor industry, and is a nasty byproduct of meth labs. But phosphine is also made naturally by some species of anaerobic bacteria—organisms that live in the oxygen-starved environments of landfills, marshlands, and even animal guts.

Put simply, phosphine shouldn’t be in the Venusian atmosphere. It’s extremely hard to make, and the chemistry in the clouds should destroy the molecule before it can accumulate to the observed amounts. But it’s too early to conclude that life exists beyond Earth’s shores. Scientists caution that the detection itself needs to be verified, as the phosphine fingerprint described in the study could be a false signal introduced by the telescopes or by data processing.

 

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Io (Jupiter) is the densest moon in the Solar System.

Density is one of the simplest non-fundamental properties of matter you can imagine. Every object that exists, from the microscopic to the astronomical, has a certain amount of energy-at-rest intrinsic to it: what we commonly call mass. These objects also take up a given amount of space in three dimensions: what we know as volume. Density is just the ratio of these two properties: the mass of an object divided by its volume.

Our Solar System itself was formed some 4.5 billion years ago the way all solar systems are formed: from a cloud of gas in a star-forming region that contracted and collapsed under its own gravity. Recently, thanks to observatories such as ALMA (the Atacama Large Millimetre/submillimetre Array), we've been able to directly image and analyze the protoplanetary disks that form around these newborn stars for the first time.

 

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Using data from a NASA instrument onboard India’s Chandrayaan-1 mission, scientists have, for the first time, found the oxidised iron mineral hematite at high latitudes on the Moon.

The findings come as a surprise to planetary scientists since the lunar surface is virtually devoid of any oxygen.

Iron is highly reactive with oxygen and forms rust, which is commonly seen on Earth. However, on the Moon, the hydrogen in solar wind blasts the surface, which acts in opposition to oxidation. This makes the presence of highly oxidised iron-bearing minerals, such as hematite, on the Moon an unexpected discovery.

According to researchers from University of Hawai’i, the lunar hematite may have formed with the help of oxygen from the Earth’s upper atmosphere that has been continuously blown to the lunar surface by solar winds during the past several billion years. 

 

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The Parker Solar Probe is a NASA Space Probe launched in 2018 with the mission of making observations of the outer corona of the Sun.

The Parker Solar Probe rocket lifted off from Cape Canaveral, Florida.

The probe is set to become the fastest-moving manmade object in history. Its data promises to crack longstanding mysteries about the Sun's behaviour.

It is the first space craft to be named after a living person - astrophysicist Eugene Parker, 91, who first described solar wind in 1958

Over the course of seven years, Parker will make 24 loops around our star to study the physics of the corona, the place where much of the important activity that affects the Earth seems to originate.

The probe will dip inside this tenuous atmosphere, sampling conditions, and getting to just 6.16 million km (3.83 million miles) from the Sun's broiling "surface".

 

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The Crab Nebula, the result of a supernova noted by Earth-bound chroniclers in 1054 A.D., is filled with mysterious filaments that are not only tremendously complex, but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion. The Crab Nebula spans about 10 light-years. In the nebula's very center lies a pulsar: a neutron star as massive as the Sun but with only the size of a small town. The Crab Pulsar rotates about 30 times each second.

This beautiful nebula is relatively easy to locate due to its location near a bevy of bright stars and recognizable constellations. Although it can be seen at some time of night all year except from roughly May through July when the sun appears too close, the best observing comes from late fall through early spring.

To find the Crab Nebula, first draw an imaginary line from bright Betelgeuse in Orion to Capella in Auriga. About halfway along that line you will find the star Beta Tauri (or Elnath) on the Taurus-Auriga border.

Having identified Beta Tauri, backtrack a little more than a third of the way back to Betelgeuse and you should find the fainter star Zeta Tauri easily. Scanning the area around Zeta Tauri should reveal a tiny, faint smudge. It is located about a degree from the star (that’s about twice the width of a full moon) more or less in the direction of Beta Tauri.

Binoculars and small telescopes are useful for finding the object and showing its roughly oblong shape, but are not powerful enough to show the filimentary structure or any of its internal detail.

 

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Jupiter's moon Ganymede is the largest satellite in the solar system. Larger than Mercury and Pluto, and only slightly smaller than Mars, it would easily be classified as a planet if were orbiting the sun rather than Jupiter.

Ganymede is the seventh moon and third Galilean satellite outward from Jupiter, orbiting at about 665,000 miles (1.070 million kilometers). It takes Ganymede about seven Earth-days to orbit Jupiter.

Daytime temperatures on the surface average minus 171 degrees Fahrenheit to minus 297 degree F, and night temperatures drop to -193 degree C. In 1996, astronomers using the Hubble Space Telescope found evidence of a thin oxygen atmosphere. However, it is too thin to support life as we know it; it is unlikely that any living organisms inhabit Ganymede.

Ganymede is the only satellite in the solar system to have a magnetosphere. Typically found in planets, including Earth and Jupiter, a magnetosphere is a comet-shaped region in which charged particles are trapped or deflected. Ganymede's magnetosphere is entirely embedded within the magnetosphere of Jupiter.

 

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Every year the world sends satellites and spacecraft to space to improve communications on Earth or to explore planets and moons. But how are these heavy objects sent to space?

A rocket ride

We launch things into space by putting them onto rockets that carry tonnes of propellants (fuel). These propellants give the rocket enough energy to boost away from Earth's surface. Because of Earth's gravitational pull the heaviest and the largest satellites or spacecraft need the biggest of rockets with most propellant.

Action and reaction

We now know that we need a rocket to send objects to space, but how does a rocket lift off? The most important idea behind a rocket's lift off is Issac Newton's over 300-year-old law, which states that for every action there is an equal and opposite reaction.

If you have seen photos and videos of a rocket launch, you would not have missed seeing exhaust streaming from the bottom of the rocket. This exhaust is the flames, hot gases and smoke that come from burning the rockets propellants. This exhaust pushes out from a rocket's engine down toward the ground. This is the action force. In response to this action, the rocket begins moving in the opposite direction, lifting off the ground. This is the reaction force.

Let's keep moving

While the rocket will lift off due to the reactive force of the exhaust, Earth's gravity will continue pulling it down. So how does the rocket continue moving upwards? When a rocket bums propellants and pushes out exhaust an upward force called thrust is created. To launch, the rocket needs enough propellants to create thrust that is greater than the force of the gravity pulling the rocket down. A rocket needs to speed up to at least 29,000 km/hr and fly above most of the atmosphere in a curved path around Earth. This will ensure that the gravity will not pull it back down.

 

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