Lifeboat Foundation

A comet that will make a (somewhat) close approach to the Earth in September 2024 is already creating excitement among amateur astronomers. Comets are unpredictable beasts, and a great many have proven disappointing – but C/2023 A3 (Tsuchinshan-ATLAS) has many of the characteristics required to put on the best display for at least a decade.

Comets visit the inner solar system quite frequently, but few can be seen with the naked eye. Most are either regular visitors (short period) that have been slowly losing material on previous approaches to the Sun and don’t have enough left to be very bright. Others never get close enough to Earth to put on a show.

Tsuchinshan-ATLAS passes both those tests. Its orbit is so long it there is debate as to whether it visited the inner solar system 80,000 years ago, or if it never has. At closest approach, it will be 58 million kilometers (36 million miles) or just under 0.39 AU (Earth-Sun distance) from the Earth.

By understanding how asteroids function, we can know more about how to knock them off course.

The DART mission moved an asteroid, setting the stage for planetary defense strategies that could avoid collision with more dangerous objects.

This larger-than-expected result shows the change in Dimorphos’ orbit was not just from the impact of the DART spacecraft. The larger part of the change was due to a recoil effect from all the ejected material flying off into space, which Ariel Graykowski of the SETI Institute and colleagues estimated as between 0.3 percent and 0.5 percent of the asteroid’s total mass.

A First Success

Continue reading “New Results From NASA’s DART Mission Confirm We Could Deflect Deadly Asteroids” »

What would we do if we spotted a hazardous asteroid on a collision course with Earth? Could we deflect it safely to prevent the impact?

Last year, NASA’s Double Asteroid Redirection Test (DART) mission tried to find out whether a “kinetic impactor” could do the job: smashing a 600kg spacecraft the size of a fridge into an asteroid the size of an Aussie Rules football field.

Early results from this first real-world test of our potential planetary defense systems looked promising. However, it’s only now that the first scientific results are being published: five papers in Nature have recreated the impact, and analyzed how it changed the asteroid’s momentum and orbit, while two studies investigate the debris knocked off by the impact.

For a few tense days this January, a roughly 70-metre asteroid became the riskiest observed in over a decade. Despite the Moon’s attempt to scupper observations, the asteroid is now known to be entirely safe.

*Join ESA, NASA and Asteroid Day LIVE from 19:00 CET this evening in “Killing asteroids — with the experts”, to find out more*.

Initial observations of an asteroid dubbed ‘2022 AE1’ showed a potential Earth impact on 4 July 2023 – not enough time to attempt deflection and large enough to do real damage to a local area should it strike.

A new model explains a possible route for the extraterrestrial rock before it blasted Earth.

Peptide chain formation from amino acids such as glycine is a key step in the emergence of life. Unlike their synthesis by living systems, how peptide chains grow under abiotic conditions is an open question given the variety of organic compounds discovered in various astrophysical environments, comets and meteorites. We propose a new abiotic route in the presence of protonated molecular dimers of glycine in a cold gaseous atmosphere without further need for a solid catalytic substrate. The results provide evidence for the preferential formation of mixed protonated dimers of glycine consisting of a dipeptide and a glycine molecule instead of pure protonated glycine dimers. Additional measurements mimicking a cosmic-ray impact in terms of internal excitation show that a single gas-phase collision induces polymerization via dehydration in both the mixed and pure dimer ions.

Based on analysis of preliminary information from several sources, NASA experts believe the object was a meteoroid about two feet in diameter weighing about 1,000 pounds. The angle and speed of entry, along with signatures in weather radar imagery, are consistent with other naturally occurring meteorite falls. Radar and other data indicate that meteorites did reach the ground from this event.

Although meteorites tend to hit Earth’s atmosphere at high speeds, they slow as they travel through the atmosphere, breaking into small fragments before hitting the ground. Meteorites cool rapidly and generally are not a risk to the public.

On Feb. 3, an asteroid more than three times as long as it is wide safely flew past Earth at a distance of about 1.1 million miles (1.8 million kilometers, or a little under five times the distance between the Moon and Earth). While there was no risk of the asteroid—called 2011 AG5—impacting our planet, scientists at NASA’s Jet Propulsion Laboratory in Southern California closely tracked the object, making invaluable observations to help determine its size, rotation, surface details, and, most notably, shape.

This close approach provided the first opportunity to take a detailed look at the asteroid since it was discovered in 2011, revealing an object about 1,600 feet (500 meters) long and about 500 feet (150 meters) wide—dimensions comparable to the Empire State Building. The powerful 230-foot (70-meter) Goldstone Solar System Radar antenna dish at the Deep Space Network’s facility near Barstow, California, revealed the dimensions of this extremely elongated asteroid.

“Of the 1,040 near-Earth objects observed by planetary radar to date, this is one of the most elongated we’ve seen,” said Lance Benner, principal scientist at JPL who helped lead the observations.