Asteroid 2003 SD220 will safely fly past Earth on Dec. 24 at a distance of 6.8 million miles (11 million kilometers). Scientists at NASA's Jet Propulsion Laboratory in Pasadena, California, have generated the highest-resolution images to date of this asteroid using the Deep Space Network's 230-foot (70-meter) antenna at Goldstone, California. The radar images were acquired between Dec. 17 and Dec. 22, when the distance to this near-Earth object (NEO) was narrowing from 7.3 million miles (12 million kilometers) to almost the flyby distance.
"The radar images data suggest that asteroid 2003 SD220 is highly elongated and at least 3,600 feet [1,100 meters] in length," said Lance Benner of JPL, who leads NASA's asteroid radar research program. "The data acquired during this pass of the asteroid will help us plan for radar imaging during its upcoming closer approach in 2018."
Three years from now, the asteroid will safely fly past Earth again, but even closer, at a distance of 1.8 million miles (2.8 million kilometers). The 2018 flyby will be the closest the asteroid will get to Earth until 2070, when it is expected to safely fly past our planet at a distance of about 1.7 million miles (2.7 million kilometers).
"There is no cause for concern over the upcoming flyby of asteroid 2003 SD220 this Christmas Eve," said Paul Chodas, manager of NASA's Center for NEO Studies at JPL. "The closest this object will come to Santa and his eight tiny reindeer is about 28 times the distance between Earth and the moon."
Radar has been used to observe hundreds of asteroids. When these primitive denizens of the solar system pass relatively close to Earth, radar is a powerful technique for studying their sizes, shapes, rotation, surface features and roughness, and for improving the calculation of their orbits.
JPL hosts the Center for Near-Earth Object Studies for NASA's Near-Earth Object Observations Program within the agency's Science Mission Directorate.
Source: NASA press release
After 50 years of sending rockets, satellites, and payloads into orbit, humanity has created something of a “space junk” problem. Recent estimates indicate that there are more than 170 million pieces of debris up there, ranging in size from less than 1 cm (o.4 in) to a few meters in diameter. Not only does this junk threaten spacecraft and the ISS, but collisions between bits of debris can cause more to form, a phenomena known as the Kessler Effect.
Scientists recently discovered the hottest planet ever found – with a surface temperature greater than some stars. As the hunt for planets outside our own solar system continues, we have discovered many other worlds with extreme features. And the ongoing exploration of our own solar system has revealed some pretty weird contenders, too. Here are seven of the most extreme.
When you consider that age of the Universe – 13.8 billion years by our most recent counts – and that which is “observable” to us measures about 27.6 billion light years in diameter, you begin to wonder why we haven’t found signs of extra-terrestrial intelligence (ETI) beyond our Solar System. To paraphrase Enrico Fermi, the 20th century physicists who advanced the famous Fermi Paradox – “where the heck are all the aliens?”
From prayer and sacrifice to sunbathing, humans have worshipped the sun since time immemorial. And it’s no wonder. At around 150m km away, it is close enough to provide the light, heat and energy to sustain the entire human race. But despite the fact that our parent star has been studied extensively with modern telescopes – both from home and in space – there’s a lot we don’t know about it.
Scientists have long tried to explain the origin of a mysterious, large and anomalously cold region of the sky. In 2015, they came close to figuring it out as a study showed it to be a “supervoid” in which the density of galaxies is much lower than it is in the rest of the universe. However, other studies haven’t managed to replicate the result.
Collapsing stars are a rare thing to witness. And when astronomers are able to catch a star in the final phase of its evolution, it is a veritable feast for the senses. Ordinarily, this process consists of a star undergoing gravitational collapse after it has exhausted all of its fuel, and shedding its outer layers in a massive explosion (aka. a supernova). However, sometimes, stars can form black holes without the preceding massive explosion.
The announcement of a seven-planet system around the star TRAPPIST-1 earlier this year set off a flurry of scientific interest. Not only was this one of the largest batches of planets to be discovered around a single star, the fact that all seven were shown to be terrestrial (rocky) in nature was highly encouraging. Even more encouraging was the fact that three of these planets were found to be orbiting with the star’s habitable zone.
Since it was first proposed in the 1960s to account for all the “missing mass” in the Universe, scientists have been trying to find evidence of dark matter. This mysterious, invisible mass theoretically accounts for 26.8% of the baryonic matter (aka. visible matter) out there. And yet, despite almost fifty years of ongoing research and exploration, scientists have not found any direct evidence of this missing mass.
Since the late 1920s, astronomers have been aware of the fact that the Universe is in a state of expansion. Initially predicted by Einstein’s Theory of General Relativity, this realization has gone on to inform the most widely-accepted cosmological model – the Big Bang Theory. However, things became somewhat confusing during the 1990s, when improved observations showed that the Universe’s rate of expansion has been accelerating for billions of years.
The extra-solar planet known as Proxima b has occupied a special place in the public mind ever since its existence was announced in August of 2016. As the closest exoplanet to our Solar System, its discovery has raised questions about the possibility of exploring it in the not-too-distant future. And even more tantalizing are the questions relating to its potential habitability.