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Comet Makes a Pit Stop Near Jupiter's Asteroids
NASA ^ | 02/25/2021 | Claire Andreoli, Donna Weaver / Ray Villard,Calla Cofield

Posted on 02/25/2021 9:12:36 PM PST by BenLurkin

After traveling several billion miles toward the Sun, a wayward young comet-like object orbiting among the giant planets has found a temporary parking place along the way. The object has settled near a family of captured ancient asteroids, called Trojans, that are orbiting the Sun alongside Jupiter. This is the first time a comet-like object has been spotted near the Trojan population.

The unexpected visitor belongs to a class of icy bodies found in space between Jupiter and Neptune. Called "Centaurs," they become active for the first time when heated as they approach the Sun, and dynamically transition into becoming more comet-like.

Visible-light snapshots by NASA's Hubble Space Telescope reveal that the vagabond object shows signs of comet activity, such as a tail, outgassing in the form of jets, and an enshrouding coma of dust and gas. Earlier observations by NASA's Spitzer Space Telescope gave clues to the composition of the comet-like object and the gasses driving its activity.

"Only Hubble could detect active comet-like features this far away at such high detail, and the images clearly show these features, such as a roughly 400,000-mile-long broad tail and high-resolution features near the nucleus due to a coma and jets," said lead Hubble researcher Bryce Bolin of Caltech in Pasadena, California.

Describing the Centaur's capture as a rare event, Bolin added, "The visitor had to have come into the orbit of Jupiter at just the right trajectory to have this kind of configuration that gives it the appearance of sharing its orbit with the planet. We’re investigating how it was captured by Jupiter and landed among the Trojans. But we think it could be related to the fact that it had a somewhat close encounter with Jupiter."

The research team's computer simulations show that the icy object, called P/2019 LD2 (LD2), probably swung close to Jupiter about two years ago. The planet then gravitationally punted the wayward visitor to the Trojan asteroid group's co-orbital location, leading Jupiter by about 437 million miles.

The research team's computer simulations show that the icy object, called P/2019 LD2 (LD2), probably swung close to Jupiter about two years ago. The planet then gravitationally punted the wayward visitor to the Trojan asteroid group's co-orbital location, leading Jupiter by about 437 million miles.

The nomadic object was discovered in early June 2019 by the University of Hawaii's Asteroid Terrestrial-impact Last Alert System (ATLAS) telescopes located on the extinct volcanoes, one on Mauna Kea and one on Haleakala. Japanese amateur astronomer Seiichi Yoshida tipped off the Hubble team to possible comet activity. The astronomers then scanned archival data from the Zwicky Transient Facility, a wide-field survey conducted at Palomar Observatory in California, and realized that the object was clearly active in images from April 2019.

They followed up with observations from the Apache Point Observatory in New Mexico, which also hinted at the activity. The team observed the comet using Spitzer just days before the observatory's retirement in January 2020, and identified gas and dust around the comet nucleus. These observations convinced the team to use Hubble to take a closer look. Aided by Hubble's sharp vision, the researchers identified the tail, coma structure and the size of the dust particles and their ejection velocity. These images helped them confirm that the features are due to relatively new comet-like activity.

Although LD2's location is surprising, Bolin wonders whether this pit stop could be a common pull-off for some sunward-bound comets. "This could be part of the pathway from our solar system through the Jupiter Trojans to the inner solar system," he said.

The unexpected guest probably will not stay among the asteroids for very long. Computer simulations show that it will have another close encounter with Jupiter in about another two years. The hefty planet will boot the comet from the system, and it will continue its journey to the inner solar system.

"The cool thing is that you're actually catching Jupiter flinging this object around and changing its orbital behavior and bringing it into the inner system," said team member Carey Lisse of the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. "Jupiter controls what's going on with comets once they get into the inner system by altering their orbits."

The icy interloper is most likely one of the latest members of the so-called "bucket brigade" of comets to get kicked out of its frigid home in the Kuiper belt and into the giant planet region through interactions with another Kuiper belt object. Located beyond Neptune's orbit, the Kuiper belt is a haven of icy, leftover debris from our planets' construction 4.6 billion years ago, containing millions of objects, and occasionally these objects have near misses or collisions that drastically alter their orbits from the Kuiper belt inward into the giant planet region.

The bucket brigade of icy relics endure a bumpy ride during their journey sunward. They bounce gravitationally from one outer planet to the next in a game of celestial pinball before reaching the inner solar system, warming up as they come closer to the Sun. The researchers say the objects spend as much or even more time around the giant planets, gravitationally pulling on them—about 5 million years—than they do crossing into the inner system where we live.

"Inner system, 'short-period' comets break up about once a century," Lisse explained. "So, in order to maintain the number of local comets we see today, we think the bucket brigade has to deliver a new short-period comet about once every 100 years."

Seeing outgassing activity on a comet 465 million miles away from the Sun (where the intensity of sunlight is 1/25th as strong as on Earth) surprised the researchers. "We were intrigued to see that the comet had just started to become active for the first time so far away from the Sun at distances where water ice is barely starting to sublimate," said Bolin.

Water remains frozen on a comet until it reaches about 200 million miles from the Sun, where heat from sunlight converts water ice to gas that escapes from the nucleus in the form of jets. So the activity signals that the tail might not be made of water. In fact, observations by Spitzer indicated the presence of carbon monoxide and carbon dioxide gas, which could be driving the creation of the tail and jets seen on the Jupiter-orbiting comet. These volatiles do not need much sunlight to heat their frozen form and convert them to gas.

Once the comet gets kicked out of Jupiter's orbit and continues its journey, it may meet up with the giant planet again. "Short-period comets like LD2 meet their fate by being thrown into the Sun and totally disintegrating, hitting a planet, or venturing too close to Jupiter once again and getting thrown out of the solar system, which is the usual fate," Lisse said. "Simulations show that in about 500,000 years, there's a 90% probability that this object will be ejected from the solar system and become an interstellar comet."

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, in Washington, D.C. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, managed the Spitzer mission for NASA's Science Mission Directorate in Washington, D.C. Science operations were conducted at the Spitzer Science Center at IPAC at Caltech. Spitzer's entire science catalogue is available via the Spitzer data archive, housed at the Infrared Science Archive at IPAC. Spacecraft operations were based at Lockheed Martin Space in Littleton, Colorado.


TOPICS: Astronomy; Science
KEYWORDS: asteroid; asteroids; astronomy; centaurs; co; co2; comet; comets; jupiter; p2019ld2; science
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1 posted on 02/25/2021 9:12:37 PM PST by BenLurkin
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To: BenLurkin
In before the obligatory Uranus jokes. This is really fascinating, thanks for posting.

the Kuiper belt is a haven of icy, leftover debris from our planets' construction 4.6 billion years ago, containing millions of objects

So that's where the missing socks went...

2 posted on 02/25/2021 9:19:14 PM PST by Billthedrill
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To: Billthedrill

Comets are simply balls of condensed gases that accumulate on socks that are transported by the washing machine/transporter to the Kuiper belt.

(True fact)


3 posted on 02/25/2021 9:39:40 PM PST by 17th Miss Regt
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To: BenLurkin

Forget about that comet. The real problem is all the methane you guys are releasing!

4 posted on 02/25/2021 9:50:01 PM PST by TigersEye (Will the Younger Dryas Impact you? )
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To: BenLurkin

The James Webb Space Telescope, scheduled to be launched, October 2021 will have a primary mirror of 6.5 meters (21.3255 feet)in diameter. The Hubble has a primary mirror of 2.4 meters (7.87402 feet) in diameter. Think of the detail the James Webb will have with its 6.25 times more collecting area! Also, the James Webb has tremendous infra red capabilities (from 0.6 to 28 micrometers) while the Hubble studies objects in the ultraviolet spectrum. As the James Webb studies further into the cosmos, light shifts into the infrared spectrum.


5 posted on 02/25/2021 10:33:59 PM PST by jonrick46 ( Leftnicks chase illusions of motherships at the end of the pier.)
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To: BenLurkin

That doesn’t jibe with what I understood about the Trojan points. I thought the Trojan points were where the Sun, planetary, and moons gravity cancelled each other out and the objects in them were locked in place. So how can Jupiter throw the comet out again?


6 posted on 02/26/2021 1:34:46 AM PST by rxh4n1
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To: 17th Miss Regt

I hope someday some one can answer the question as to why when you put a pair of socks into the dryer only one ever comes out.


7 posted on 02/26/2021 1:45:12 AM PST by jmacusa (Liberals. Too stupid to be idiots.)
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To: BenLurkin

Just passin’ through:

“Simulations show that in about 500,000 years, there’s a 90% probability that this object will be ejected from the solar system and become an interstellar comet.”


8 posted on 02/26/2021 1:47:51 AM PST by jacknhoo ( Luke 12:51; Think ye, that I am come to give peace on earth? I tell you, no; but separation. )
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To: rxh4n1
Perhaps because every object in the universe, stars and planets don't revolve in perfectly circular orbits.

They wobble, sometimes moving in elliptical orbits. Maybe in doing so any orbital bodies around them might have their orbits disturbed?

9 posted on 02/26/2021 1:48:37 AM PST by jmacusa (Liberals. Too stupid to be idiots.)
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To: jonrick46
....scheduled to be launched, October 2021 ...

Development began in 1996 for a launch that was initially planned for 2007 and a 500-million-dollar budget. They have now spent 10 billion dollars on this. I do hope it works someday but this is a prime example of how Government screws up everything it touches.

10 posted on 02/26/2021 2:17:49 AM PST by Nateman (Keep Liberty Alive! Article V)
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To: rxh4n1

I think you are thinking of LaGrange points.


11 posted on 02/26/2021 6:38:51 AM PST by brooklin
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To: rxh4n1

Each planet also has trojan points relative to its orbits and any moons it might have. I would imagine that the gravitational environment of Jupiter would be pretty darn complex. It has a lot of moons.


12 posted on 02/26/2021 7:03:24 AM PST by zeugma (Stop deluding yourself that America is still a free country.)
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To: jonrick46
I'm wondering if any attempt will be made to combine the Hubble and Webb telescopes. Not physically, obviously, but by having them both attempt to resolve the same object simultaneously, you would have an effectively much larger scope.
13 posted on 02/26/2021 7:05:22 AM PST by zeugma (Stop deluding yourself that America is still a free country.)
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To: jmacusa
I hope someday some one can answer the question as to why when you put a pair of socks into the dryer only one ever comes out.

I doubt it. It is an eternal conundrum. My solution to this spatial anomaly is to buy many pairs of socks that are all identical, so when one goes missing I don't notice, other than sometimes having an odd number of socks, when it should always be an even number.

14 posted on 02/26/2021 7:07:18 AM PST by zeugma (Stop deluding yourself that America is still a free country.)
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To: zeugma
There are other ground based, extremely large, telescopes in the works that will be monsters compared to what is being used today. One is the Giant Magellan Telescope (GMT) located in Chili's Las Campanas Observatory. With its Six off-axis 8.4 meter (27-foot diameter) segments surrounding a central on-axis 27-foot diameter segment, together forming a single optical surface creating an effective 80.38 foot diameter primary mirror, it will be able to study the atmospheres of planets orbiting stars. The closest star to earth is four light-years away. The GMT will reach far from our solar system to search for signs of biochemistry—alien life. You will have to wait for its results because the telescope is scheduled to have first light in 2029.

One of the most sophisticated engineering aspects of the telescope is what is known as “adaptive optics.” The telescope’s secondary mirrors are actually flexible. Under each secondary mirror surface, there are hundreds of actuators that will constantly adjust the mirrors to counteract atmospheric turbulence. These actuators, controlled by advanced computers, will transform twinkling stars into clear steady points of light. It is in this way that the GMT will offer images that are ten times sharper than the Hubble Space Telescope’s.

To keep this information interesting, Chili's Los Espantajo beaches can be seen due west of the GMT.

The Thirty Meter Telescope (TMT) is another extremely large telescope to be located on Hawaii's peak of Mauna Kea mountain. With its 98-foot primary mirror, it will study the universe through both visible and infrared light. Following the success of current large segmented-mirror telescopes--such as the Keck 10-m telescop--it will have 492 hexagonal glass segments. It will provide 12 times sharper resolution than the Hubble Space Telescope.

The TMT will allow astronomers to study the farthest reaches of the Universe, up to the “dark ages” when the first sources of light were formed, just after the Big Bang. It also will study objects through time, such as first galaxies and massive black holes. It will also help astronomers better detect and characterize exoplanets, and may even lead to the first detections of biosignatures beyond Earth. Hold on to your hat! If you think this stuff is dull, just think! With its visible light capabilities, you will be also able to look at girls in bikinis on Honolulu's beaches on the south of the Island. Yes!

In 2009, the TMT collaboration selected Mauna Kea as the preferred site at an altitude of 13451.44 feet to build and operate the TMT. Building a telescope in the crater of a dormant volcano would block out light pollution from cities. The ocean water around the Big Island is consistently warm, which keeps the atmosphere stable. A stable atmosphere makes for a clearer telescope image. For that reason, a dozen telescopes already exist on the mountain. However,the site has been resisted by many native Hawaiians and activists. Traditionally, Mauna Kea is sacred land. Some Native Hawaiians believe it is where Wakea, the sky God, met with the Earth Goddess, Papa, and created the Big Island, the first child island of Hawaii. The religious resistance resulted in its construction permit issued a temporary stand-down by the liberal governor and terminated by the Hawaii Supreme Court. However, despite the hurdles, finally Hawaii's Supreme Cour ruled that the construction is legal and Gov. David Ige extended the window to begin construction from 60 days to two years. Construction was resumed and first light is planned on November 2, 2026.

The extremely European Large Telescope (ELT) on Mt. Cerro Armazones in Chile, with its 130 foot segmented primary mirror, will gather light in the visible light spectrum and you will be able to watch girls on Chili's Antofagasta's Balneario Municipal beach in their bikinis--LOL! It will have a 14 ft diameter secondary mirror, which will also be supported by adaptive optics, eight laser guided star units and multiple large science instruments. Wow! It has around 256 times the light gathering area of the Hubble Space Telescope and, according to the ELT's specifications, would provide images 16 times sharper than those from Hubble.

Like the Grand Magellan, it will advance astrophysical knowledge by enabling detailed studies of planets around other stars, the first galaxies in the Universe, supermassive black holes, and the nature of the Universe's dark sector, and to detect water and organic molecules in protoplanetary disks around other stars.

Hold onto your seat belts, the ELT will have first light in 2025.

Finally, a word of warning. Looking at girls with these telescopes, with today's Cancel Culture, may result in your termination from the observatory sight. Don's say I didn't warn you.

15 posted on 02/26/2021 2:44:38 PM PST by jonrick46 ( Leftnicks chase illusions of motherships at the end of the pier.)
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To: brooklin

Yes. That’s it. Close, but no cigar. Thanks.


16 posted on 02/26/2021 3:49:29 PM PST by rxh4n1
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To: jmacusa

The other one is usually hiding up in the leg of a pair of pants that was also in the dryer.


17 posted on 02/26/2021 5:04:13 PM PST by MachIV
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To: BenLurkin

Braking thrust.


18 posted on 02/26/2021 10:12:26 PM PST by Ozark Tom
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To: jonrick46; mewzilla; Chode; Lockbox; carriage_hill; tubebender; SkyDancer; Salamander; infool7; ...

Did they quadruple the check Grinding Spec’s on the Mirror ?

We don’t need a repeat of the fox paw on Hubble.

Hubble’s Mirror Flaw | NASA

https://www.nasa.gov/content/hubbles-mirror-flaw

Shortly after the Hubble Space Telescope’s launch in 1990, operators discovered that the observatory’s primary mirror had an aberration that affected the clarity of the telescope’s early images. Hubble’s primary mirror was built by what was then called Perkin-Elmer Corporation, in Danbury, Connecticut...

Ultimately the problem was traced to miscalibrated equipment during the mirror’s manufacture. The result was a mirror with an aberration one-50th the thickness of a human hair, in the grinding of the mirror.


19 posted on 02/26/2021 10:41:04 PM PST by mabarker1 ((Congress- the opposite of PROGRESS!!! A fraud, a hypocrite, a liar. I'm a member of Congress !!!!)
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To: MachIV

Hmmmm. Yes, more than likely. But still it IS strange, isn’t it, that one sock seems to just... I dunno... go off into some other dimension.


20 posted on 02/26/2021 10:48:46 PM PST by jmacusa (Liberals. Too stupid to be idiots.)
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