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Category Archives: Comets

Comets: Zoom Astronomy – Enchanted Learning

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PARTS OF A COMET Nucleus: The nucleus is the frozen center of a comet's head. It is composed of ice, gas, and dust. The nucleus contains most of the comet's mass but is very small (about 1 to 10 km across - or more).

Coma: The coma is the roughly spherical blob of gas that surrounds the nucleus of a comet; it is about a million km across. The coma is comprised of water vapor, carbon dioxide gas, ammonia, dust, and neutral gases that have sublimed from the solid nucleus. The coma and the nucleus form the head of a comet.

Ion Tail: A tail of charged gases (ions) always faces away from the sun because the solar wind (ions streaming from the sun at high velocities) pushes it away (it is also called the plasma tail). When the comet is approaching the Sun, the ion tail trails the comet: when the comet is leaving of the Sun, the ion tail leads. The tail fades as the comet moves far from the Sun. The ion tail can be well over 100 million km long.

Dust Tail: The dust tail is a long, wide tailcomposed of microscopic dust particles that are buffeted by photons emitted from the Sun; this tail curves slightly due to the comet's motion. The tail fades as the comet moves far from the Sun. Hydrogen Envelope: Hydrogen gas surrounds the coma of the comet and trails along for millions of miles (it is usually between the ion tail and the dust tail). The hydrogen envelope is about 10 million km across at the nucleus of the comet and about 100 million km long. It is bigger when the comet is near the Sun.

A COMET'S ORBIT Comets orbit the Sun in highly elliptical orbits. Their velocity increases greatly when they are near the Sun and slows down at the far reaches of the orbit. Since the comet is light only when it is near the Sun (and is it vaporizing), comets are dark (virtually invisible) throughout most of their orbit. The solar wind pushes the tail away from the Sun.

Some comets crash into the Sun or get so close that they burn up; these comets are called sungrazers.

COMET EXPLORATION NASA's Stardust Mission will visit the Comet Wild 2 in 2004. It will take a sample of comet particles and return them to Earth. The small spacecraft (about 770 pounds = 350 kg) was launched February 7, 1999 and rendezvoused with comet Wild 2 in January, 2004. It will return to Earth on January 15, 2006, and land in western Utah, USA. Comet Wild 2 (aka Comet 81P) is a short-period comet that was discovered by the Swiss astronomer Paul Wild on January 6, 1978. The comet's nucleus is about 3 miles (5 km) across. Wild 2 orbits the Sun every 6.39 years; its elliptical orbit ranges from about Mars' orbit to Jupiter's orbit.

COSMIC SNOWBALLS There is a new and very controversial theory that comets (composed of frozen water) are constantly bombarding the Earth. These "cosmic snowballs" have (perhaps) been seen by the visible imaging system of the Polar Satellite. In theory, these frozen comets vaporize in the atmosphere, adding water vapor to the environment.

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Comets: Zoom Astronomy - Enchanted Learning

Workington Comets suffer heavy defeat at Sheffield

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Last updated at 11:04, Friday, 05 September 2014

Sheffield 52 Workington Comets 40: Workington Comets slumped to a heavy defeat against the bottom side in the Premier League.

Kyle Howarth, front, battles with Sheffield's Ben Wilson

The Comets had been looking at the very least for a bonus point but they returned home with nothing, falling away after a bright start to the meeting.

After six heats the two sides were all square at 18-18 but from that point the Tigers pulled clear and a 5-1 to the Comets in the last heat was scant consolation for what had gone before.

The Comets had also lost 52-40 at Owlerton in a League Cup meeting early in the season, so to that degree they were at least consistent.

Before the last heat maximum the visitors had grabbed a 5-1 in heat five and the only other race advantage came when a second place from Josh Grajczonek as a tac ride helped them to a 5-3.

Co-promoter Steve Whitehead was acting team manager and admitted he was disappointed by the defeat.

He said: I know they are bottom of the league but they rode better than that tonight. Simon Stead is still class; Nico Covatti had his best meeting for them and all the other chipped in well.

Kyle Howarth had declared himself unfit on Tuesday after a crash on Monday but today he said he was ready to go. We sorted that and he was excellent. He desperately wanted to ride in heat 15 and he followed Josh round for a 5-1.

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Workington Comets suffer heavy defeat at Sheffield

What Comets, Parking Lots and Charcoal Have in Common

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In this delightful portrayalof Comet 67P/Churyumov-Gerasimenko, we see the 2.5-mile-wide object close to true colorwith downtown Los Angeles, Calif. for size reference.Compare to the same image (below) as viewed from space. Despite appearances in photos, comets are coal-black objects. Credit: ESA and anosmicovni

All the pictures weve seen of Rosettas target comet 67P/C-G show it reflecting brightly against the background of outer space. And well they should. Space is black as night. But if we were to see the comet against a more familiar earthly backdrop, wed be shocked by its appearance. Instead of icy white, Rosettas would appear the color of a fresh asphalt parking lot. Most comets, including Rosettas, are no brighter than the charcoal briquettes you use to grill hamburgers.

Astronomers rank an objects reflectivityby its albedo (al-BEE-do). A body that reflects 100% of the lightis said to have an albedo of 1.0.Venus albedo is .75 and reflects 75% of the light it receives from the sun, while the darker Earths average is 30%. Trees and thedarker-toned continents reflect much less light compared to Venus pervasive cloud cover. In contrast, the coal-dark moon reflects only 12% of the sunlight falling on it and fresh asphalt just 4% smack in the middle ofthe 2-6% range of most known comets.

Photo of Comet 67P/C-G taken by Rosetta on August 6, 2014. Against the blackness of space, it appears whitish-grey. Credit: ESA

The brightest object in the solar system is Saturns icy moon Enceladus with areflectivity of 99%.So why are comets so dark? Its funny because before we sent the Giotto spacecraft to snap close-up pictures of Halleys Comet in 1986, astronomers thought comets, being made of reflective ice, were naturally white.Not Halley and not every comet seen up close since then.

Comets are as dark as charcoal but appear light only because the sun illuminates them against the blackness of outer space. I shone a flashlight on a charcoal briquette (left) to simulate comet lighting.The same charcoal, when viewed in normal light, appears black. Credit; Bob King

Astronomers hypothesizethat a comet grows a dark skin both from accumulated dust andirradiation of its pristine ices by cosmic rays. Cosmic rays loosen oxygen atoms from water ice, freeing them to combine with simple carbon molecules present on comets to form larger, more complex and darker compounds resembling tars and crude oil.

Comet colored parking lots have been the rage for years. Both comets and fresh asphalt reflect about the same amount of light. Credit: Bob King

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What Comets, Parking Lots and Charcoal Have in Common

Saturday serve: Can the Comets work in Canberra? Mike Valetta says yes

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Saturday Serve

Michael Bevan of NSW, Jamie Cox of Tasmania, Darren Lehmann of South Australia, Paul Reiffel of Victoria, Adam Gilchrist of Western Australia, Rod Tucker of Canberra and Stuart Law of Queensland launch the 1999-2000 Mercantile Mutual Cup. Photo: Getty Images

Does anyone remember big Swervin' Mervin Hughes steaming in at Manuka Oval?

All zinked up, marvellous mo, a bit heavier than when he was in his prime, but the great man was still an Australian hero and the marquee man for the Canberra Comets.

Then there was young gun Brad Haddin, a brash Queanbeyan junior ready to take the cricket world by storm.

Merv Hughes in the field for the ACT Comets in 1997. Photo: Pat Scala

It's been 14 years of waiting, wondering and hoping, but the Comets are (almost) back sans big Merv, of course.

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It's easy to get caught up in the romance of a sporting comeback, be it a legend coming out of retirement or a defunct team being revived after more than a decade.

Anyone in Canberra sport remembers the Comets, the Cannons and the Cosmos. Everyone in Canberra wants a cricket team, an NBL side and an A-League franchise.

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Saturday serve: Can the Comets work in Canberra? Mike Valetta says yes

Blue Comets top Cougars in three

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ASHEBORO Southwestern Randolph and Asheboro High School are in the same county, the same town and the same conference.

So any time the schools face off, its tough to predict the outcome.

Thursday night, the varsity volleyball teams met at AHS and, in the end, the Blue Comets notched a 25-14, 25-20, 25-20 win to improve to 4-0 in the Mid-Piedmont Conference.

The competition was great, Asheboro coach Karen Blanchard said. There were a lot of rallies. The girls just practice hard every day. Im pleased with how they played together. Everybody played up to par and we were able to work in every offensive play.

The Blue Comets (7-1 overall) went on a 13-0 run in the first game and never looked back. The Cougars pulled to within 10, but couldnt come closer as Asheboro took a 1-0 match lead.

Southwestern Randolph responded with a 4-0 run to start the second game, but the Blue Comets went on a seven-point streak to go ahead 10-8. The Cougars came back to tie it at 16-all on an Anna Laton kill, but Asheboro scored the next five points and kept Southwestern Randolph at bay to go ahead 2-0 in the match.

The third game was less streaky, featuring seven lead changes and eight ties before the Blue

Comets grabbed a 12-11 lead on a Courtney King hit. Asheboro proceeded to go on a 4-0 run and grew its lead to as many as six. The Cougars pulled within four points twice, but couldnt get over the hump as King ended the game with a kill for the match point.

We have a lot of young ones who play really timid, Southwestern Randolph coach Darby Kennedy said. When we play stron teams, especially Asheboro, they feel like they get in each others way. They need to trust each other. A lot of its that its Asheboro.

King led the Blue Comets with 19 kills, while Salem Davidson added eight and Amy Yates chipped in seven. Yates had 16 points, and Hannah Ferguson and King each had eight. Gilliam Foscue dished out 28 assists and Ferguson had nine.

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Blue Comets top Cougars in three

Comets, Meteors payments will help send teams into orbit

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Sara Hungerford will line up for the Meteors this weekend. Photo: Jeffrey Chan

ACT Meteors coach Andrew Dawson hopes the introduction of WNCL and Twenty20 match payments helps his squad rise to a new level this season as it targets a home grand final berth.

The Meteors will start their pre-season campaign when they play the NSW Breakers, South Australia Scorpions and Tasmania Roar at Blacktown this weekend.

Meteors players will earn match payments for the first time this season, boosting their earning potential and raising the standard within the squad.

Cricket Australia introduced a pay structure with the country's top athletes capable of earning up to $80,000 per season.

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The Meteors payments will be far less about $200 per 50 over match, $150 for a Twenty20 and $75 for each night away from home but Dawson said the team's training program has already stepped up in intensity.

"Everyone is going harder. There are overseas players coming in as well, so everyone is trying to ramp it up," Dawson said.

"There's definitely accountability. The girls put in so much time and effort and they've done it without getting paid. The money they receive now covers expenses, but it is a nice top-up. It's a starting point."

The ACT Comets will also play their first pre-season matches as they attempt to win selection for World Cup trial matches against Afghanistan and Ireland later this month.

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Comets, Meteors payments will help send teams into orbit

Cricket ACT and Country Cricket NSW form alliance for Comets promotion

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Merv Hughes in his glory days with the Comets in 1997. Photo: Pat Scala

Cricket ACT is poised to form a powerful alliance with Country Cricket NSW and Cricket NSW, strengthening its bid for the Comets to be re-admitted into the national one-day competition in the summer of 2015-16.

The ACT Comets were axed from the domestic one-day competition in 2000, but are set to be reincarnated as the ACT-NSW Country Comets in a united push to return to the highest level of domestic cricket by next year.

Cricket ACT, Country Cricket NSW and NSW Cricket met in Sydney this week to finalise details of a memorandum of understanding that will officially divide playing talent across NSW and the ACT.

Canberra's Jono Dean plays for Adelaide in the Big Bash League but may get more representative chances closer to home with the ACT-NSW Country Comets. Photo: Katherine Griffiths

While the NSW Blues would still be the major representative team based in Sydney, Canberra would be the central base for all NSW players outside the Sydney metropolitan area.

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It would more than double the population of the ACT's current catchment area to approximately 3 million, also aiding Cricket ACT's long-term ambition for expansion into the Big Bash League and Sheffield Shield.

Cricket ACT chairman Ian McNamee confirmed the proposal for a Comets team to join the 2015-16 national one-day competition would be an agenda item at Cricket Australia's board meeting in Melbourne on September 17-18.

Cricket ACT chairman Ian McNamee. Photo: Andrew Johnston

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Rock Around the Clock – Bill Haley & His Comets [Guitar tabs] – Video

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Rock Around the Clock - Bill Haley His Comets [Guitar tabs]
Rock Around the Clock - Bill Haley His Comets [Guitar tabs] Sheet music available on: https://www.jellynote.com/sheet-music-tabs/bill-haley-his-comets/rock-around-the-clock/504a13ead2235a3ff94ad4...

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Rock Around the Clock - Bill Haley & His Comets [Guitar tabs] - Video

Comets look to figure out depth in preseason

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After a week and a half of practice the MUCC Comets hit the road to play an exhibition game against he Lumsden Devils on Thursday, August 28. Although the Comets won the game 37-6 head coach Dave Rogers said it was about giving all the players an opportunity to compete. It indicated some points. We had some pretty good execution on offense in the beginning of the game. We also had some outstanding linebacker play in the game, he said. The game also helped the coaching staff figure out where each player fits into the teams depth chart. In addition to indicating positives, the game also shed some light on areas that the Comets need to improve upon before the start of the regular season later this week. We need to clean up the timing on offense, a little bit of pass rush moves on the defensive line. I think the other thing we need to clean up a little bit of special teams play and we need to emphasize some ball security. That is always important. Rogers said the coaching staff was pleased with how the players performed in the exhibition game but said making the jump to regular season on September 5 against the Tisdale Tornadoes in Tisdale at 4 p.m. is a big step. On Friday we are playing for real and we need to be able to move our team to the next level. Throughout the season it is going to be about the teams who improve the most week in and week out. The Comets are not doing anything specific to prepare for the Tornadoes rather they are focusing on their own team development. At this point the focus is totally about us and improving our execution on offense and we are going to work a little bit on tackling on defense. The game is also the first step on a road towards some lofty expectations set by the players. We have some talented players and some who are very committed to the program and the kids have set for themselves some high expectations. We are fortunate that we have a strong group of 12 grade 12s.who set high expectations.

greg.wiseman@sunmedia.ca @melfortjournal

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Six points keep Workington Comets play-off hopes alive

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By John Walsh

Last updated at 12:13, Monday, 01 September 2014

Scunthorpe 53 Workiington Comets 37: Workington Comets were unable to bring home a point from yesterdays trip to Scunthorpe as they completed a hectic three days of speedway.

Joe Jacobs leads Scunthorpes Josh Auty

A 10-point defeat at Plymouth on Friday was followed by a successful double-header at home on Saturday when they thrashed Rye House 63-31 and then beat Scunthorpe 49-41.

The management team had been looking for a minimum of six points from the weekend to maintain their play-off challenge and thats exactly what they got.

Co-promoter Steve Whitehead, who stood in as team manager at Scunthorpe for Tony Jackson who was unable to travel, was happy enough with the six points.

He said: We had to get the maximum points from both home matches which we did and it would have been nice to pick up bonus points on our travels but we didnt manage that.

However, we have moved up the table and we are still on target for a top-six place, building some momentum for the play-offs.

It was unfortunate that we were without two key riders at Scunthorpe, Josh Grajczonek and Rene Bach, because they were required to ride in a world event in Poland. Unfortunately, they got there but the meeting was rained off.

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Six points keep Workington Comets play-off hopes alive

Gruelling weekend ahead for Workington Comets

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Last updated at 11:21, Friday, 29 August 2014

This weekend can change Workington Comets season, insists owner Laura Morgan.

Comets face a gruelling four fixtures in under 48 hours and will want something from all of them to keep their play-off dream alive.

They ride away at Plymouth tonight, welcome Rye House and Scunthorpe tomorrow in a double-header followed by an away trip on Sunday.

Morgan said: Its a worry having double-headers. Its difficult for everybody including riders, mechanics and machinery. Financially they are not really good for the club either.

But its not impossible to reach the play-offs and it has been our aim this season. Weve not had consistent track time and have been a five-man team for quite some time.

Comets need to bounce back after a disappointing run of only one win in their last seven meetings, including a dismal trip to Ipswich last Thursday and an even more disappointing home defeat to Glasgow the following night.

Morgan said: I still cant believe what happened. It wasnt good enough. Even in the last heat the noise in the grandstand was incredible. The fans found it from somewhere and that is what it is all about.

But she is positive looking forward to the weekends fixtures.

She said: Historically we go well at Plymouth and I dont see why we cant get at least a point. Tomorrow I simply expect to win both.

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Gruelling weekend ahead for Workington Comets


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