. 24/7 Space News .
IRON AND ICE
The Bee-Zed asteroid orbits in the opposite direction to planets
by Staff Writers
Sao Paulo, Brazil (SPX) Jun 28, 2017


Bee-Zed is unusual because it shares a planet's orbit, because its own orbit is retrograde, and above all, because it has been stable for millions of years. "Instead of being ejected from orbit by Jupiter, as one would expect, the asteroid is in a configuration that assures stability thanks to co-orbital resonance, meaning its motion is synchronized with the planet's, avoiding collisions," Morais said.

In our solar system, an asteroid orbits the Sun in the opposite direction to the planets. Asteroid 2015 BZ509, also known as Bee-Zed, takes 12 years to make one complete orbit around the Sun. This is the same orbital period as that of Jupiter, which shares its orbit but moves in the opposite direction to the planet's motion.

The asteroid with the retrograde co-orbit was identified by Helena Morais, a professor at Sao Paulo State University's Institute of Geosciences and Exact Sciences (IGCE-UNESP). Morais had predicted the discovery two years earlier, so much so that the article describing observations of the asteroid published in Nature, is noted by Morais in the News and Views section of the same issue of the journal.

"It's good to have confirmation," Morais told. "I was sure retrograde co-orbits existed. We've known about this asteroid since 2015, but the orbit hadn't been clearly determined, and it wasn't possible to confirm the co-orbital configuration. Now it's been confirmed after more observations that reduced the number of errors in the orbital parameters. So, we're sure the asteroid is retrograde, co-orbital and stable."

In partnership with Fathi Namouni at the Cote d'Azur Observatory in France, Morais developed a general theory on retrograde co-orbitals and retrograde orbital resonance.

The paper by Paul Wiegert of the University of Western Ontario, Canada, published in March in Nature, describes how object 2015 BZ509, detected in January 2015, using the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) in Hawaii, was tracked using the Large Binocular Telescope in Arizona. The confirmation that its orbit is retrograde and co-orbital with Jupiter came from these additional observations.

Retrograde orbits are rare. It is estimated that only 82 of the more than 726,000 known asteroids are orbiting the "wrong way". By contrast, prograde co-orbitals that move 'with traffic' are nothing new; Jupiter alone is accompanied by some 6,000 Trojan asteroids that share the giant planet's orbit.

Bee-Zed is unusual because it shares a planet's orbit, because its own orbit is retrograde, and above all, because it has been stable for millions of years. "Instead of being ejected from orbit by Jupiter, as one would expect, the asteroid is in a configuration that assures stability thanks to co-orbital resonance, meaning its motion is synchronized with the planet's, avoiding collisions," Morais said.

The asteroid crosses Jupiter's path every six years, but owing to their co-orbital resonance, they never come closer than 176 million km, far enough to avoid major disturbances to the orbit of the asteroid, although Jupiter's gravity is essential to keeping the planet and Bee-Zed in a 1:1 retrograde resonance.

All the planets and most of the asteroids in the solar system orbit the Sun in the same direction because the solar system emerged from a revolving cloud of dust and gas, most of the constituent objects of which continue to revolve as they did before.

"The vast majority of retrograde objects are comets. Their orbits are typically inclined as well as retrograde. The most famous, of course, is Halley's comet, which has a retrograde orbit with an inclination of 162 , practically identical to that of 2015 BZ509," Morais said.

In the final stages of planetary formation, she explained, small bodies were expelled far from the Sun and planets, forming the spherical shell of debris and comets known as the Oort cloud.

"At these distances, the Milky Way's gravitational effects disturb small bodies. To begin with, they orbited close to the plane of the ecliptic in the same direction as the planets, but their orbits were deformed by the galaxy's tidal force and by interactions with nearby stars, gradually becoming more inclined and forming a more or less spherical reservoir," Morais said.

If the orbits of these bodies are disturbed - by a passing star, for example - they return to paths close to the planets of the solar system and can become active comets. "The icy small bodies warm up as they approach the Sun, and the ice sublimes to form a coma [a dense cloud of gas and dust particles around a nucleus] and often a tail, making the comets observable," she explained.

In the case of 2015 BZ509, the most surprising feature is its long period of stability. In their commentary in Nature, Morais and Namouni say the particularly long life of 2015 BZ509 in its retrograde orbit makes it the most intriguing object in the vicinity of Jupiter. "Further studies are needed to confirm how this mysterious object arrived at its present configuration," they conclude.

Wiegert speculates that Bee-Zed probably originated in the Oort cloud, like the Halley family comets. In any event, more research will be necessary to reconstruct Bee-Zed's epic voyage through the solar system.

"Actually, 2006 BZ8 might even enter into co-orbital retrograde resonance with Saturn in the future. Our simulations showed that resonance capture is more likely for objects with retrograde orbits than for those orbiting in the same direction as the planets," Morais said.

Bee-Zed is expected to stay in the same state for another million years. Its discovery has led researchers to suspect that asteroids in retrograde co-orbits with Jupiter and other planets may be more common than was previously thought, making the theory expounded by Morais and Namouni even more compelling.

IRON AND ICE
NASA's Asteroid-Hunting Spacecraft a Discovery Machine
Pasadena CA (JPL) Jun 06, 2017
NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) mission has released its third year of survey data, with the spacecraft discovering 97 previously unknown celestial objects in the last year. Of those, 28 were near-Earth objects, 64 were main belt asteroids and five were comets. The spacecraft has now characterized a total of 693 near-Earth objects since the mission wa ... read more

Related Links
Fundacao de Amparo a Pesquisa do Estado de Sao Paulo
Asteroid and Comet Mission News, Science and Technology


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

IRON AND ICE
NASA Statement on National Space Council

Don't look down: glass bottom skywalk thrills in China

Silicon-on-Seine: world's biggest tech incubator opens in Paris

India, Portugal Shake Hands on Space Cooperation

IRON AND ICE
After two delays, SpaceX launches broadband satellite for IntelSat

Aerojet Rocketdyne advocates solar electric propulsion as central element of deep space exploration

Ariane 5 launch proves reliability and flies new fairing

80th consecutive success for Ariane 5 with launch of Hellas Sat, Inmarsat and ISRO

IRON AND ICE
Mars Rover Opportunity continuing science campaign at Perseverance Valley

The Niagara Falls of Mars once flowed with lava

Russian Devices for ExoMars Mission to Be Ready in Fall 2017

No One Under 20 Has Experienced a Day Without NASA at Mars

IRON AND ICE
China heavy-lift carrier rocket launch fails: state media

Yuanwang-3 completes ship check mission, ready for Chang'e-5 lunar probe launch

China prepares to launch second heavy-lift carrier rocket

China to launch Long March-5 Y2 in early July

IRON AND ICE
SES Transfers Capacity from AMC-9 Satellite Following Significant Anomaly

HTS Capacity Lease Revenues to Reach More Than $6 Billion by 2025

Second launch doubles number of Iridium NEXT satellites in orbit to 20

OneWeb inaugurates production line Assembly, Integration, and Test of OneWeb satellites

IRON AND ICE
NIST 'noise thermometry' yields accurate new measurements of boltzmann constant

SES and MDA Announce First Satellite Life Extension Agreement

Space Debris Mitigation Mission Successfully Launched on June 23rd, 2017

True romance in the air at Tokyo virtual reality show

IRON AND ICE
Extreme Atmosphere Stripping May Limit Exoplanets' Habitability

Complex Organic Molecules Found On "Space Hamburger"

Why Does Microorganism Prefer Meager Rations Over Rich Ones

NASA diligently tracks microbes inside the International Space Station

IRON AND ICE
Mid-infrared images from the Subaru telescope extend Juno spacecraft discoveries

Earth-based Views of Jupiter to Enhance Juno Flyby

NASA's Juno Spacecraft to Fly Over Jupiter's Great Red Spot July 10

Topsy-Turvy Motion Creates Light-Switch Effect at Uranus









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.