Radar imaging at NASA's Goldstone Solar System Radar on June 12 and 14, 2009, revealed that near-Earth asteroid 1994 CC is a triple system. Image Credit: NASA/JPL/GSSR
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Radar images have shown that a near-Earth object is actually a triple system; an asteroid with two small moons. NASA’s Goldstone Solar System Radar on June 12 and 14, 2009, revealed the new informaton about Asteroid 1994 CC. It came within 2.52 million kilometers (1.56 million miles) on June 10. Prior to the flyby, very little was known about this celestial body. 1994 CC is only the second triple system known in the near-Earth population. A team led by Marina Brozovic and Lance Benner, both scientists at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., made the discovery.
Asteroid 1994 CC encountered Earth within 2.52 million kilometers (1.56 million miles) on June 10. Prior to the flyby, very little was known about this celestial body. Image Credit: NASA/JPL/GSSR
1994 CC consists of a central object about 700 meters (2,300 feet) in diameter that has two smaller moons revolving around it. Preliminary analysis suggests that the two small satellites are at least 50 meters (164 feet) in diameter. Radar observations at Arecibo Observatory in Puerto Rico, led by the center’s director Mike Nolan, also detected all three objects, and the combined observations from Goldstone and Arecibo will be utilized by JPL scientists and their colleagues to study 1994 CC’s orbital and physical properties.
The next comparable Earth flyby for asteroid 1994 CC will occur in the year 2074 when the space rock trio flies past Earth at a distance of two-and-a-half million kilometers (1.6 million miles).
Of the hundreds of near-Earth asteroids observed by radar, only about 1 percent are triple systems.
Ed von Renouard working at Honeysuckle Creek Tracking Station in Australia was the first person to see images from the Apollo 11 moonwalk. Image courtesty of Bruce Ekert.
Six hundred million people, or one fifth of humanity at the time, watched Neil Armstrong’s first steps on the Moon in 1969. But seeing live transmissions from that historic event wouldn’t have been possible – and the Apollo missions wouldn’t have possible either – without reliable communications and accurate tracking capabilities.
To support the Apollo Program, NASA built the Manned Space Flight Network (MSFN) with three 85 foot (26 meter) antennas equally spaced around the world at Goldstone, California, Honeysuckle Creek, Australia and Fresnedillas (near Madrid), Spain.
Because of the movie “The Dish” however, most people think the Parkes Radio Antenna was the only dish used in Australia. But the Honeysuckle Creek dish was the real star of the Apollo missions. Most notably, it supplied voice and telemetry contact with the lunar and command modules but it also provided the first televised pictures of the Apollo 11 moonwalk.
“It was a job well done by many people all over the world,” said Bruce Ekert, a technician with the Honeysuckle Creek Tracking Station. “When I reflect that we were part of history, it is still amazing that it came together and worked so smoothly.”
The Honeysuckle Creek Tracking Station (HSK) was a radio-quiet location in the Australian Alps surrounded by granite peaks 32km southwest of Canberra, Australia’s capital.
Ekert helped install a microwave relay link from HSK to the Red Hill Radio Terminal in Canberra. “This link was the “missing link” as at that time, there was only a telephone line from HSK to Canberra, and this was unsuitable for TV pictures,” Ekert told Universe Today.
Apollo antenna coverage. Credit: NASA
Ekert was working for the government telecommunications department and in April 1969 he was told his next job would be to install a microwave link so that when Australia’s side of the world was pointed toward the Moon, all the communications to the Moon and back could be relayed to NASA and mission control in Houston.
Honeysuckle Creek Tracking Station during Winter (July) 1969. Photo courtesy Bruce Ekert
It may have been summer in the US, but in Australia it was winter. 1969 was cold and snowy, especially in snow country at 1200m (3600ft) up in the mountains, making the work difficult.
“It was cold and we had a lot of snow that year,” Ekert said, “Aligning microwave dishes on towers in cold weather, the bolts tend to lock up, and it’s difficult to move them around to get the best signal. Moving them with cold hands and cold steel is not the easiest things to do. But we installed microwave dishes on towers and equipment in the buildings. We also had to install a temporary tower with two dishes on it to redirect the signal through the mountains to get it out to the rest of the world.”
“We were running by the seat of our pants at one stage,” Ekert continued. “It was all thrown together and we knew it would work, but still, since we threw it together we hoped it would work according to plan.”
Ekert and his co-workers had to make sure the temporary links stayed working for the duration of the Apollo 11 mission.
“We maintained the equipment in a hands-off position,” he said. “As we say now, if it ain’t broke don’t fix it. We worked for the complete duration of the mission, but we weren’t allowed to touch anything if it was working – just let it run. If it had failed, then we would have had to fix it, but since everything just coasted along and there weren’t any problems, we just watched and waited like everyone else.”
But those at HSK had one little advantage. “The staff at Honeysuckle Creek actually were the first people in the world to see the pictures coming from the Moon, by a few milliseconds,” Ekert said. “So that is our claim to fame.”
Ed von Renouard, working at HSK was the first man in the world to see the pictures from the Moon as they came from the receiver in the dish. (See top image of Ed back in 1969, and below is Ed with Bruce Ekert)
Louise from the HSK reunion organizing committee, Bruce Ekert, and Ed von Renouard at the Apollo 11 celebrations in Australia. Photo Courtesy Bruce Ekert.
But then after 8 minutes, NASA decided the larger 64meter Parkes Radio Telescope, 300 kilometers away, was getting a clearer signal and switched over for the remaining coverage of the spacewalk for the next two-and-a-half-hours.
Yes, there was a wind storm at Parkes, which threatened to blow the dish off course, as portrayed in “The Dish,” but Ekert said the movie was a typical Hollywood type creation.
“There were no crises where they were going to lose communications,” he said. “There was a big storm, where they had winds up to 60 mph (100 kph) at Parkes not long after the landing happened. They did fear the dish might be blown off course, but they always had the standby of Honeysuckle Creek, which was still receiving pictures, and at that point the moon had risen higher in the sky and pictures were actually better. So if the Parkes dish had actually been blown off course, they would have immediately switched back to Honeysuckle Creek.”
The original Honeysuckle dish now at Tidbinbilla. Courtesy Bruce Ekert.
Parkes was part of MSFN’s “wing” stations to provide back-up and additional coverage. This meant that each of the three locations around the world would have two stations capable of communicating with Apollo spacecraft at lunar distances. In addition to just redundancy, there was another reason for having two Apollo-capable stations at each location. For project Apollo, communications used the higher frequency S-Band (around 2.2GHz), and the beam width of the 85 foot antennas at those frequencies was only 0.43 degree. Ideally, one antenna would track the Command Service Module in Lunar orbit and the other would track the Lunar Module to the surface.
Parkes was also called in to assist with the Apollo 13 emergency.
In addition, a number of other stations supported Apollo, including a facility at Tidbinbilla, 20 km away from HSK, which also had dedicated Apollo equipment and people to operate as an additional receive/transmit facility.
More permanent microwave relays were installed, and HSK was part of all the Apollo missions, and in 1974 at the conclusion of the Skylab program, HSK Creek joined the Deep Space Network as Deep Space Station 44, working deep space missions like Viking, Voyager, Pioneer and more. It was closed in December 1981, with its 26 meter antenna relocated to the Canberra Deep Space Communications Complex at Tidbinbilla, and renamed Deep Space Station 46, where it is still in use today.
The original HSK site has been leveled, and only the concrete foundations remain, but in 2001 an outdoor display was added. During Apollo 11 celebrations in July of this year, Ekert joined about 200 other people who worked at HSK, Parkes and Tidbinbilla to commemorate their achievements with Apollo.
Bruce Ekert on July 21, 2009 at the Honeysuckle Creek site, taken from the position of the communications tower. Below is the concrete pad which marks the position of the building. At the very back of the photo is the place where the HSK Dish was situated. Courtesy Bruce Ekert
“We traveled to the site of the HSK tracking station, for a ceremony unveiling a new plaque to show visitors and tourists where history was made on 21st July, 1969,” said Ekert. “We then moved over to another part of the site and a time capsule was filled with memorabilia from 1969 until now. My wife, who is Russian, put in a 50 Ruble note, with the words that there is not a “Cold War” anymore. The time capsule was buried, with instructions for the park rangers that it is to be dug up in 60 years time to mark the 100th anniversary of man’s first footsteps on the moon.”
Neil Armstrong also sent a note of congratulations for the ceremony, touching on the misconceptions the rest of the world might have because of things portrayed in the movie “The Dish.”
“Some of you, I expect, may have had mixed emotions about the film, THE DISH. I understand, because as technical people, we like things to be correct and accurate. And the film did not always accurately capture the roles of those of you at Honeysuckle Creek, those of you at Parkes, and those of you at Tidbinbilla. But for most of the viewers of the film around the world, those were not the details that they would remember anyway. What they will remember is that down in Australia there were some very dedicated people, with some very big antennae and complex electronic equipment that did remarkable things that were instrumental in the success of man’s first flights to the moon. They will have a sense that you were having a great time doing what you were doing. And what they remember will, in fact, be the truth.”
—from Neil Armstrong’s message to the Canberra Deep Space Communications Complex
The celebrations continued in Australia in Canberra and at exactly 12.51pm local time, they showed a replay of the moon walk, with Neil Armstrong jumping down off the ladder of the lunar module to the surface of the Moon at exactly 12.56pm.
Some of the Honeysuckle team underneath the old antenna, DSS-46, at Tidbinbilla on Monday 20th July 2009. Credit: Honeysucklecreek.net
“The audio came over the auditorium sound system, and the atmosphere was awesome,” Ekert said. “It was a great celebration, where we patted ourselves on the back and had a salutatory drink to the whole situation.”
And a well deserved drink it was. The rest of the world sends its thanks to those who made watching television from the Moon possible.
Greetings, fellow SkyWatchers! Have you been watching Jupiter and the Moon make a pass at each other in the early morning sky? What an incredible sight. With the slightly later rise of Selene during the weekend hours, we can take advantage of the earlier evening to do some deep sky studies. However, if you’re just in the mood to kick back in a lawn chair and do a little stargazing, you’ll probably spot some early Perseid meteors gracing the night. I’ll give you a full report on the watching the Perseid Meteor shower just a little bit closer to the date so you won’t forget! For now… Why not join me in the back yard? We’ve got a little history, a little mystery and a telescope waiting for you…
Friday, August 7, 2009 – Today marks the 1726 birth of James Bowdoin, astronomer and friend of Benjamin Franklin. Although Bowdoin suffered many years from consumption, which was finally the cause of his death, he was always vigorous in public affairs. He was one of the founders, and first president, of the American academy of arts and sciences, and left it his valuable library. He also aided in founding the Massachusetts humane society, and in 1779 was made a fellow of Harvard College. He was given the degree of LL.D. by the University of Edinburgh, and was a fellow of the royal societies of London and Edinburgh. Several of his papers appear in the memoirs of the society, among which is one whose object is to prove that the sky is a real concave body enclosing our system, and that the Milky Way is an opening in this, through which the light of other systems reaches us.
What do you think he would have thought if he could be with us tonight as we return to our studies with the globular M14, one of the clusters nearer to the galactic center? Located about 16 degrees (less than a handspan) south of Alpha Ophiuchi (RA 17 37 36 Dec +03 14 45), this 9th magnitude, Class VIII cluster can be spotted with larger binoculars, but only fully appreciated with the telescope.
When studied spectroscopically, globular clusters are found to be much lower in heavy element abundance than stars such as own Sun. These earlier generation stars (Population II) began their formation during the birth of our galaxy, making globular clusters the oldest formations we can study. In comparison, the disk stars have evolved many times, going through cycles of starbirth and supernova, which in turn enriched the heavy element concentration in star-forming clouds. Of course, as you may have guessed, M14 breaks the rules. M14 contains an unusually high number of variable stars—in excess of 70—with many of them known to be the W Virginis type. In 1938, a nova appeared in M14, but it was undiscovered until 1964, when Amelia Wehlau of the University of Ontario was surveying the photographic plates taken by Helen Sawyer Hogg. The nova was revealed on eight of these plates taken on consecutive nights and showed itself as a 16th magnitude star—andwas believed to be at one time almost five times brighter than the cluster members. Unlike 80 years earlier with T Scorpii in M80, actual photographic evidence of the event existed. In 1991, the eyes of the Hubble were turned its way, but neither the suspect star nor traces of a nebulous remnant were discovered. Then, 6 years later, a carbon star was discovered in M14. To a small telescope, M14 will offer little to no resolution and will appear almost like an elliptical galaxy, lacking in any central condensation. Larger scopes will show hints of resolution, with a gradual fading toward the cluster’s slightly oblate edges. A true beauty!
Saturday, August 8, 2009 – On this date in 2001, the Genesis Solar Particle Sample Return mission was launched on its way toward the Sun. On September 8, 2004, it returned with its sample of solar wind particles. Unfortunately, a parachute failed to deploy, causing the sample capsule to plunge unchecked into the Utah soil. Although some of the specimens were contaminated, many did survive the mishap. So what is ‘‘star stuff?’’ Mostly highly charged particles generated from a star’s upper atmosphere flowing out in a state of matter known as plasma.
Before moonrise, let’s study one of the grandest of all solar winds as we seek out an area about three finger-widths above the Sagittarius teapot’s spout as we have a look at the magnificent M8 (RA 18 03 37 Dec +24 23 12). Visible to the unaided eye as a hazy spot in the Milky Way, fantastic in binoculars, and an area truly worth study in any size scope, this 5,200-light-year-diameter area of emission, reflection, and dark nebulae has a rich history. Its involved star cluster—NGC 6530—was discovered by Flamsteed around 1680 and the nebula by Le Gentil in 1747. Cataloged by Lacaille as III.14 about 12 years before Messier listed it as number 8, its brightest region was recorded by John Herschel, and dark nebulae were discovered within it by Barnard.
Tremendous areas of starbirth are found in this region, while young, hot stars excite the gas in a region known as the ‘‘Hourglass’’ around the stars Herschel 36 and 9 Sagittarii. Look closely around cluster NGC 6530 for Barnard Dark Nebulae B 89 and B 296 at the nebula’s southern edge. . .and try again on a darker night. No matter how long you choose to swim in the ‘‘Lagoon,’’ you will surely find more and more things to delight both the mind and the eye!
Sunday, August 9, 2009 – On this date in 1976, the Luna 24 mission was launched on a return mission of its own, not to retrieve solar winds’ samples but lunar soil! Remember this mission as we take a look at its landing site in the weeks ahead. Tonight we’ll return to the nebula hunt as we head about a finger-width north and just slightly west of M8 for the ‘‘Trifid’’ (RA 18 02 23 Dec +23 01 48).
M20 was discovered by Messier on June 5, 1764, and much to his credit, he described it as a cluster of stars encased in nebulosity. This is truly a wonderful observation, since the Trifid could not have been easy to spot, given his equipment. Some 20 years later William Herschel (although he usually avoided repeating Messier objects) found M20 of enough interest to assign separate designations to parts of this nebula—IV.41, V.10, V.11, V.12.
The word ‘‘Trifid’’ was used to describe its beauty by John Herschel. Although M20 is a very tough call in binoculars, it is not impossible with good conditions to see the light of an area that left its home nearly a millennium ago. Even smaller scopes will pick up this faint, round, hazy patch of both emission and reflection, but you will need aversion to see the dark nebula that divides it. This was cataloged by Barnard as B 85. Larger telescopes will find the Trifid as one of the very few objects that actually appears much in the eyepiece as it does in photographs—with each lobe containing beautiful details, rifts, and folds best seen at lower powers. Look for its cruciform star cluster and its fueling multiple system while you enjoy this triple treat tonight!
For now, keep an eye on the sky for the coming of the annual Perseid Meteor Shower! You’ll see a great increase in activity beginning now – despite the moonlight. The peak will be mid-week, but I’ll be back with an update on who, when, where, why and how very soon… Until then? Wishing you clear skies!
This week’s awesome images are (in order of appearance): James Bowdoin (historical image), (credit—NOAO/AURA/NSF), Genesis Spacecraft (credit—NASA), M8: the Lagoon Nebula (credit—NOAO/AURA/NSF), Luna 24 launch (press release photo) and M20: the Trifid nebula (credit—Palomar Observatory, courtesy of Caltech). We thank you so much!
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Venus is the second planet from the Sun, orbiting at an average distance of 108.2 million km. Venus takes a total of 224.7 days to orbit the Sun.
The Sun and Venus are vastly different sizes, of course. The diameter of Venus is 12,103 km, while the diameter of the Sun is 1.4 million km. In other words, the Sun is 115 times larger than Venus. You could fit about 1.5 million planets the size of Venus inside the Sun.
Venus is a terrestrial planet. It has a metal core surrounded by a mantle of silica rock. This is surrounded by a thin crust of rock. The Sun, on the other hand, is a massive ball of hydrogen and helium gas. Temperatures at its core are hot enough to ignite nuclear fusion – more than 15 million Kelvin.
The Sun has an enormous impact on Venus. The radiation from the Sun is trapped by the thick atmosphere of Venus, raising average temperatures across the planet to around 460 °C. In fact, this makes Venus the hottest planet in the Solar System.
Both the Sun and Venus formed at the same time, 4.6 billion years ago, with the rest of the Solar System. They formed out of the solar nebula, a cloud of gas and dust that collapsed down to become the Sun and planets.
Because Venus orbits closer to the Sun than the Earth, we always see it close to the Sun in the sky. Venus is either trailing the Sun or leading it across the sky. The best times to see Venus are just before sunrise or just after sunset.
The XCOR X-Racer Prototype, built for the Rocket Racing League was flown at the AirVenture 2008, and XCOR just released a couple of videos. This is an onboard camera split view from one flight and its a lot of fun to watch. The pilot is Richard Searfoss, Astronaut (former) and Col. USAF (Ret.), and the Flight Test Engineer is Mark Street.
A conjunction of Venus occurs when Earth, Venus and the Sun are all lined up together. Imagine looking down at the Solar System from above and being able to straight line that goes through Earth, Venus and the Sun. That’s a conjunction of Venus.
There are two kinds of conjunctions that can happen: superior conjunction and inferior conjunction. A superior conjunction of Venus happens when Earth and Venus are on opposite sides of the Sun. Seen from above, it goes, Earth – Sun – Venus. An inferior conjunction of Venus occurs when Venus and Earth are on the same side of the Sun. So, if you drew a line it would go Sun – Venus – Earth.
From here on Earth, it’s not possible to see either inferior or superior conjunctions of Venus. When Venus is in a superior conjunction, it’s on the opposite side of the Sun, and the glare of the Sun is too bright to see it. The same situation happens with an inferior conjunction. In this situation, Venus is in between Earth and the Sun, and lost in the glare.
Because of the orbits of Venus and Earth, Venus very rarely passes directly in front of the Sun from our vantage point. This is called a transit of Venus, and it does occur every hundred years or so in pairs. The last transit of Venus was in 2004, and the next one will happen in 2012.
When there’s an inferior conjunction of Venus, the planet is approximately 41 million km away. It’s possible for Venus and Earth to get as close as 38.2 million km, but that happens rarely.
When seen through a telescope, Venus goes through phases, just like the Moon. When Venus is approaching its inferior conjunction, it becomes a thin sliver – but very bright. When it’s approaching a superior conjunction, we see it starting to look fully illuminated. It’s impossible to see Venus either in full inferior or superior conjunction because it gets lost in the glare of the Sun either way.
The period of rotation for Venus is 243 days. In other words, Venus takes 243 days to turn once on its axis so that the stars are in the same position in the sky.
That seems like a long time, and it is. Especially when you consider that a year on Venus only lasts 224.7 days. In other words, a day on Venus lasts longer than its year. Even stranger, Venus is rotating backwards from the rest of the planets. Seen from above its north pole, Venus is rotating clockwise, while the rest of the planets in the Solar System are turning counter-clockwise.
If you could actually stand on the surface of Venus, with the scorching heat and crushing atmospheric pressure, you would see the Sun rise in the West and then travel slowly across the sky, to set in the East. The total time from sunrise to sunrise is 116.75 days.
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Venus is similar to Earth in size, mass, density to Earth. In many ways it’s Earth’s twin planets. Of course its climate is completely different, with its hellish temperature and crushing atmospheric pressure. Oh, and don’t forget about the clouds that rain sulfuric acid. But does Venus have seasons like Earth.
No.
Obviously, Venus doesn’t have nice warm summers and cooler winters like Earth; in fact, the surface of Venus experiences no temperature variations at all. Everywhere you go in the entire planet, the temperature is the same average 460 °C. It doesn’t matter if you’re near the equator or near the poles. Whether you’re on the day side or the night side, the temperatures don’t change much from the global average of 460 °C.
Part of the reason is the fact that the axial tilt of Venus is only 2.7°. That means that the planet has very little difference between the angle of its axis during “summer” and “winter”. Our axial tilt here on Earth is 23.4°, and that significant tilt means that the hemisphere pointed towards the Sun gets a lot more energy than the hemisphere pointed away.
And the other part of the reason why Venus doesn’t experience any temperature variations is because of the thick atmosphere – 93 times more surface atmospheric pressure than we experience here on Earth. This carbon dioxide atmosphere traps the heat and distributes it around the planet.
Even though the planet rotates very slowly, with spots on the planet experiencing more than 50 days of night, the temperatures just don’t fluctuate.
And so, this is why there are no seasons on Venus.
Artist's impression of the Solar Nebula. Image credit: NASA
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Where did the planet Venus come from? What’s the origin of Venus. Actually, Venus and the rest of the planets in the Solar System all formed at the same time, out of the same nebula, about 4.6 billion years ago.
Let’s go back then, 4.6 billion years ago, before there was a Sun or any planets. In this region of space was a large diffuse cloud of cold molecular hydrogen. And then some event, like a supernova explosion, or gravitational disturbance of a passing star caused the cloud to collapse. As it collapsed, it broke up into knots of gas; each of which would eventually go on to form a star.
As the material collapsed down, it began to spin because of the conservation of momentum from all the particles in the cloud. The center of the cloud became denser and denser, eventually becoming our Sun. This was surrounded by a flattened disk of material; and within this disk is where the planets, including Venus formed. It’s believed that all the planets formed together, at the same time within this disk.
Once the Sun had enough temperature and pressure in its core to ignite fusion, it generated powerful solar winds that blasted away all of the leftover material in the Solar System. All that remained were the planets and their moons.
Astronomers know that all of the planets formed at the same time because of meteorites discovered here on Earth. No matter where in the Solar System they originally came from, all of these meteorites were formed at the same time; about 4.6 billion years ago.
So the origin of Venus is the same origin for all the planets in the Solar System. They all formed out of the solar nebula, billions of years ago.
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What planet gets closest to Venus? It actually depends on where the planets are in their orbits; but you might be surprised to know that Earth is the closest planet to Venus.
What, you were thinking Mercury gets closer to Venus? At their closest point, Mercury and Venus are separated by only 46 million km. Of course, that’s when the two planets are aligned on the same side of the Sun. When they’re on opposite sides of the Sun, Mercury and Venus are 178.7 million km away from each other.
When Earth and Venus are at their closest point, lined up on the same side of the Sun, they’re only separated by 39 million km. But when they’re on opposite sides of the Sun, Earth and Venus are separated by more than 250 million km. So for most of the time, Mercury and Venus are closer to one another.
But the planet that gets closest to Venus is Earth.
And that’s why Venus looks so large and bright from here on Earth. After the Sun and the Moon, Venus is the brightest object in the night sky. It can even shine so brightly that it casts shadows.
