Carl Sagan’s famous quote says “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.” In that famous quote, Sagan makes reference to the whole universe started off with hydrogen and helium, all stars produce helium, and then stars over a certain mass threshold produce carbon, nitrogen, oxygen and lots of heavier elements – which are also the source of the life. The star stuff is inside us – every living thing on Earth.
But, even stars aren’t powerful enough to create heavy elements like silver, gold, and cesium. Since the 1950s, scientists have wondered: where do most of the elements in the periodic table come from?
Continue reading LIGO detects gravitational waves from neutron star merger
Launched on October 15, 1997, NASA’s Cassini spacecraft Notes 1 went into orbit around Saturn on July 1, 2004. Since then, it has taken thousands of photos of Saturn, the second-largest planet in the Solar System, its prominent rings, and moons. And on September 15, 2017, Cassini plunged into Saturn’s atmosphere and disintegrated. Here are the 20 most beautiful photos that the spacecraft has sent back to Earth during its 13-year voyage around the gas giant.
Cassini was destroyed by diving into the Saturn’s atmosphere on September 15, 2017. This method of disposal was planned to avoid potential biological contamination of Saturn’s moons, since Titan, Enceladus, and other icy moons of Saturn may harbor oceans and alien life.
Continue reading 20 Best Photos of Cassini’s voyage around Saturn
About 70,000 years ago, a wandering binary stellar system passed through the Solar System’s Oort cloudNotes 1, within 120,000 AU (0.58 pc; 1.9 ly) of the Sun. 70,000 years is just a blink of an eye compared to the Earth’s age, which is 4.543 billion years. Our ancestors were about to left Africa at that time. The binary system is dubbed as Scholz’s StarNotes 2, after its discoverer. Comets perturbed from the Oort cloud would require roughly 2 million years to get to the inner Solar System. So, in the distant future, some of these comets may hit the Earth and cause mass extinctions, like the “dinosaur killer” Chicxulub impactor which impacted a few miles from the present-day town of Chicxulub in Mexico around 66 million years ago.
Continue reading Now We Know When Stars Will Be Passing Close to the Sun
On Monday, August 21, an estimated 2 million to 7.4 million Americans traveled to see the first total solar eclipse in 99 years to go coast to coast in the United States, which went from Lincoln Beach, Oregon, to Charleston, South Carolina. But, some of them were unlucky, as the weather was overcast in some places. But, luckily for them (and for us), NASA captured some amazing and beautiful images of the eclipse and published them on their website.
Continue reading Total Solar Eclipse 2017 Images From Space
On February 22, 2017, NASA astronomers have announced that seven Earth-sized planets have been discovered around an ultra-cool dwarf star named TRAPPIST-1 which is located around 39 light-years from the Earth. And what’s more – three of them are orbiting their star in the habitable zone. Then, an international team of astronomers led by the Swiss astronomer Vincent Bourrier from the Observatoire de l’Université de Genève used the NASA/ESA Hubble Space Telescope to estimate whether there might be water on the planets of TRAPPIST-1 system. Now, on August 31, 2017, the team announced that their findings suggest that “the outer planets of the system might still harbor substantial amounts of water”, including the three planets within the habitable zone of the star – TRAPPIST-1e, f, and g. This result lends further weight to the possibility that these planets may indeed be habitable.
Continue reading TRAPPIST-1 System May Contain Water
On September 1, 2017, a potentially hazardous asteroid named 3122 Florence skimmed past Earth from a mere 4.4 million miles (7 million km) distance. The huge asteroid, which is around 2.7 mile (4.4 km) wide, was the “biggest object passed this close to Earth since the NASA program to detect and track near-Earth asteroids began”, according to Paul Chodas, manager of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory in Pasadena, California. The close flyby was captured with an amateur astronomer using an 80 mm F5 Apo telescope and a Canon 6D camera, and published on youtube.
Continue reading Huge Asteroid “3122 Florence” flyby video
The Earth rotates from west to east with a linear velocity of 465.1013 m/s (1674.365 km/h) at the equator. But what would happen if the Earth stopped rotating abruptly? Online magazine Tech Insider presented a video demonstrating the development of events in this case.
Continue reading What would happen if the Earth stopped rotating?
Related: What Would Happen If the Earth Started Spinning Backward?
You have probably heard references been made to the “dark side” of the Moon – there’s even a Pink Floyd album with that name. But, in fact, there’s no “dark side” of the moon. Because it is not illuminated by the Earth, it is illuminated by the Sun. All the surface of the moon lit by the Sun as the Moon rotates. But, yes, we see only one side of the moon and here’s why.
Continue reading Why do we see only one side of the Moon?
On June 19, 2017, NASA’s Kepler space telescope team has released a mission catalog of planet candidates. The final catalog introduces 219 new exoplanet candidates, and 10 of them are near-Earth-size and orbiting their stars in the circumstellar habitable zone. Notes 1
This the eighth release of the Kepler candidate catalog. With this release, there are now 4,034 planet candidates (as of June 21, 2017) identified by Kepler space telescope, which launched by NASA on March 7, 2009, to discover Earth-size planets orbiting other stars. Of those, 2,335 have been verified as exoplanets. Of roughly 50 near-Earth size habitable zone candidates detected by Kepler, more than 30 have been verified. All the Kepler’s catalog is publicly available on NASA Exoplanet Archive.
Continue reading NASA Announces 10 New Earth Sized Planets Orbiting in Habitable Zone
We, humans, are changing our planet drastically that scientists say the world entered a completely a new geological era called “Anthropocene”. But, it seems we are not shaping only the surface and the atmosphere of Earth, human activities are changing our near-space environment as well. The change is so big that NASA’s Van Allen probes have detected a human-made barrier surrounding Earth.
Continue reading NASA Detects a Human-Made Barrier Surrounding Earth