Comets


Comet 2

Possible naked-eye comet will visit Earth for first time in 50,000-years

The comet C/2022 E3 (ZTF) could be bright enough to be spotted with the naked eye as it passes the sun and Earth at the end of the first month of 2023.
Comet C/2022 E3 (ZTF)
© Hisayoshi Sato via NASA/JPL-CaltechAn image of the Comet C/2022 E3 (ZTF) taken by astrophotographer Hisayoshi Sato as seen in a still image from a NASA video.
At the start of 2023 Earth will be visited by a newly discovered comet that may just be bright enough to be spotted with the naked eye.

The comet, named C/2022 E3 (ZTF), is currently passing through the inner solar system. It will make its closest approach to the sun, or perihelion, on Jan. 12, and will then whip past Earth making its closest passage of our planet, its perigee, between Feb. 1 and Feb. 2.

If the comet continues to brighten as it currently is, it could be visible in dark skies with the naked eye. This is difficult to predict for comets, but even if C/2022 E3 (ZTF) does fade it should still be visible with binoculars or a telescope for a number of days around its close approach.

According to NASA, observers in the Northern Hemisphere will be able to find the comet in the morning sky, as it moves in the direction of the northwest during January. C/2022 E3 (ZTF) will become visible for observers in the Southern Hemisphere in early February 2023.

Arrow Down

This asteroid impact simulator lets you destroy the world

A web app from Neal.Fun is a choose-your-own-adventure for planetary annihilation.
Impact Site
© Screenshot: Gizmodo/Neal.FunI aimed a 1,500-foot iron asteroid traveling at 38,000 miles per hour with a 45-degree impact angle at Gizmodo’s office in Midtown, Manhattan.
Hundreds of thousands of asteroids lurk in our solar system, and while space agencies track many of them, there's always the chance that one will suddenly appear on a collision course with Earth. A new app on the website Neal.fun demonstrates what could happen if one smacked into any part of the planet.

Neal Agarwal developed Asteroid Simulator to show the potentially extreme local effects of different kinds of asteroids. The first step is to pick your asteroid, with choices of iron, stone, carbon, and gold, or even an icy comet. The asteroid's diameter can be set up to 1 mile (1.6 kilometers); its speed can be anywhere from 1,000 to 250,000 miles per hour; and the impact angle can be set up to 90 degrees. Once you select a strike location on a global map, prepare for chaos.

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HAARP to bounce signal off asteroid in NASA experiment

HAARP in Alaska
© UAF/GI photo by JR AnchetaWith temperatures falling to 40 degrees below zero, a frosty landscape surrounds antennas at the High-frequency Active Auroral Research Program site in Gakona, Alaska, on Dec. 20, 2022. HAARP conducted a run-through on that date to prepare for the Dec. 27 asteroid bounce experiment.
An experiment to bounce a radio signal off an asteroid on Dec. 27 will serve as a test for probing a larger asteroid that in 2029 will pass closer to Earth than the many geostationary satellites that orbit our planet.

The High-frequency Active Auroral Research Program research site in Gakona will transmit radio signals to asteroid 2010 XC15, which could be about 500 feet across. The University of New Mexico Long Wavelength Array near Socorro, New Mexico, and the Owens Valley Radio Observatory Long Wavelength Array near Bishop, California, will receive the signal.

This will be the first use of HAARP to probe an asteroid.

"What's new and what we are trying to do is probe asteroid interiors with long wavelength radars and radio telescopes from the ground," said Mark Haynes, lead investigator on the project and a radar systems engineer at NASA's Jet Propulsion Laboratory in Southern California. "Longer wavelengths can penetrate the interior of an object much better than the radio wavelengths used for communication."

Knowing more about an asteroid's interior, especially of an asteroid large enough to cause major damage on Earth, is important for determining how to defend against it.

"If you know the distribution of mass, you can make an impactor more effective, because you'll know where to hit the asteroid a little better," Haynes said.

Many programs exist to quickly detect asteroids, determine their orbit and shape and image their surface, either with optical telescopes or the planetary radar of the Deep Space Network, NASA's network of large and highly sensitive radio antennas in California, Spain and Australia.

Doberman

1 dead, 1 hurt in dog attacks in West Memphis, Arkansas

dog attack
A man was killed and a woman badly injured by a pack of dogs in two separate attacks in West Memphis, Arkansas.

READ: https://wreg.com/news/local/dog-pack-...


Popcorn

Cryovolcanic eruption on comet 29P/Schwassmann-Wachmann reported

comet 29P/Schwassmann-Wachmann
The British Astronomical Association (BAA) is reporting a new outburst of cryovolcanic comet 29P/Schwassmann-Wachmann. On Nov. 22nd, amateur astronomer Patrick Wiggins watched 29P increase in brightness by more than 4 magnitudes--a sign that a major eruption was in progress. On Nov. 23rd, André Debackère used the Faulkes Telescope North in Hawaii to photograph the expanding shell of debris:

The Pac-Man shape of the ejecta shows that this is not a uniform global eruption. Instead, it is coming from one or more discrete sources on the comet's surface.

This fits a leading model of the comet developed by Dr. Richard Miles of the British Astronomical Association. Miles believes that 29P is festooned with ice volcanoes. There is no lava. The "magma" is a cold mixture of liquid hydrocarbons (e.g., CH4, C2H4, C2H6 and C3H8) akin to those found in lakes and streams on Saturn's moon Titan. The cryomagma is suffused with dissolved gases N2 and CO, much like carbonation in a soda bottle. These bottled-up volatiles love to explode when a fissure is opened by the warming action of sunlight.

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Fireball 5

New research reveals space debris, invisible meteors and near-Earth asteroids

In a new thesis from the Swedish Institute of Space Physics and Umeå University, unique methods for the analysis of radar data and simulations of meteoroids in the solar system are presented. The methods have been applied to confirm the existence of rare high-altitude meteors as well as to measure space debris from the Kosmos-1408 satellite. On November 25, Daniel Kastinen defends his doctoral thesis.
Daniel Kastinen
© Martin Eriksson / Daniel Kastinen (illustrationDaniel Kastinen's thesis presents results that pave the way for future research and cross-disciplinary studies on meteors as well as on space debris and near-Earth asteroids.
"My primary goal has been to carefully analyze radar measurements of meteors and space debris and evaluate the precision of the measurements. This is to improve further analysis and use the results together with the new dynamical simulations. The work paves the way for future research and allows cross-disciplinary studies on meteors as well as on space debris and near-Earth asteroids", says Daniel Kastinen.

Every day, 10-200 tons of material from space, consisting of dust- sized particles and larger pieces of material - meteoroids, fall into the Earth's atmosphere. These particles come from parent bodies such as comets and asteroids and thus date back to the time when the solar system was formed. When a meteoroid hits the Earth's atmosphere and burns up in the form of a meteor, the material is dispersed in the atmosphere. Most of these meteors are invisible to the eye but can be detected by radar.

Arrow Up

'Planet killer' asteroid found hiding in sun's glare may one day threaten Earth

"Only about 25 asteroids with orbits completely within Earth's orbit have been discovered to date because of the difficulty of observing near the glare of the sun."

Asteroid behind Sun
© DOE/FNAL/DECam/CTIO/NOIRLab/NSF/AURA/J. da Silva/SpaceengineAsteroids in the inner system are notoriously hard to detect because of the glare of the sun.
Astronomers have discovered a giant asteroid hiding in the glare of the sun that might one day cross paths with Earth

The 0.9-mile-wide (1.5 kilometers) asteroid is the largest potentially hazardous asteroid spotted in the past eight years and astronomers have dubbed it a "planet killer" because the effects of its impact would be felt across multiple continents.

The asteroid, named 2022 AP7, managed to avoid detection for so long because it orbits in the region between Earth and Venus. To spot space rocks in this area, astronomers have to look in the direction of the sun, and that is notoriously difficult due to the sun's luminosity. For example, flagship telescopes such as the James Webb Space Telescope and the Hubble Space Telescope never look toward the sun, as the star's brightness would fry their sensitive optics.

Because of that, astronomers have only a limited understanding of the nature of asteroids lurking in this region, and sometimes, surprises may happen. In 2013, a much smaller asteroid, only 66 feet wide (20 m), arrived from the direction of the sun completely without warning. That asteroid exploded above the city of Chelyabinsk in southeastern Russia, shattering windows on thousands of buildings.

Fireball 5

Large, 'potentially hazardous' asteroid will zip through Earth's orbit on Halloween

The asteroid's upper size estimate is just short of the world's tallest building.
Asteroid
© Science Photo Library - ANDRZEJ WOJCICKI via Getty ImagesAn artist's impression of a near-Earth asteroid.
A newly discovered, "potentially hazardous" asteroid almost the size of the world's tallest skyscraper is set to tumble past Earth just in time for Halloween, according to NASA.

The asteroid, called 2022 RM4, has an estimated diameter of between 1,083 and 2,428 feet (330 and 740 meters) — just under the height of Dubai's 2,716-foot-tall (828 m) Burj Khalifa, the tallest building in the world. It will zoom past our planet at around 52,500 mph (84,500 km/h), or roughly 68 times the speed of sound.

At its closest approach on Nov. 1, the asteroid will come within about 1.43 million miles (2.3 million kilometers) of Earth, around six times the average distance between Earth and the moon. By cosmic standards, this is a very slender margin.

NASA flags any space object that comes within 120 million miles (193 million km) of Earth as a "near-Earth object" and classifies any large body within 4.65 million miles (7.5 million km) of our planet as "potentially hazardous." Once flagged, these potential threats are closely watched by astronomers, who study them with radar for signs of any deviation from their predicted trajectories that could put them on a devastating collision course with Earth.

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Fireball from Solar System's edge isn't what astronomers expected

Asteroid Comet
© ISTOCK / GETTY IMAGESThis stock image shows a comet hurtling through space, with an inset of a map of Canada. Scientists recently found that a space rock that lit up the skies over Canada in February 2021 wasn't actually a comet.
Just before dawn on 22 February 2021, a fireball lit up the skies across Canada's Alberta (see video below) province when a 2-kilogram space rock vaporized as it plunged through Earth's atmosphere. Although the object hailed from the Oort Cloud — a conglomeration of comets at the edge of the Solar System — it wasn't a comet, researchers now say. Data collected during its fall suggest the object was made of rock rather than ice and behaved more like an asteroid.

Independent observers of the new work say the find sheds light on the processes that formed our Solar System and challenges the conventional wisdom that the Oort Cloud only holds icy comets. "It's telling us that there was scattering and depositing of material from all over the Solar System into the Oort Cloud," says Karen Meech, a planetary scientist at the University of Hawaii's Institute for Astronomy.

The discovery could provide support for models that suggest objects from the asteroid belt were dispersed into the Oort Cloud soon after the Solar System's birth 4.6 billion years ago, says Bill Bottke, a Solar System dynamicist at the Southwest Research Institute. "This is very exciting," he says. "Now, we have to see what we can do to explain it."

First proposed by Dutch astronomer Jan Oort in 1950, the Oort Cloud is a spherical halo of comets that stretches out halfway to Proxima Centauri, the Sun's nearest neighbor, well beyond the view of even the largest telescopes. "Everything we know about it is indirect," says Denis Vida, a meteor astronomer at Western University who led the new study.

Scientists presume the Oort Cloud became populated with comets when the gravitational muscle of Jupiter and the other giant planets scattered far and wide the icy objects that were leftover from the formation of the outer Solar System. Occasionally, a passing star will gravitationally nudge an Oort Cloud object and send it plummeting into the inner Solar System. These objects are known as long-period comets, defined by their eccentric paths that take hundreds or even thousands of years to orbit the Sun.

Comet 2

30,000 near-Earth asteroids discovered, and rising - ESA

Asteroid Eros
Asteroid Eros, as seen by NEAR Shoemaker
We have now discovered 30,039 near-Earth asteroids in the Solar System - rocky bodies orbiting the Sun on a path that brings them close to Earth's orbit. The majority of these were discovered in the last decade, showing how our ability to detect potentially risky asteroids is rapidly improving.

In-depth What is a near-Earth asteroid?

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