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Two small moons have been discovered orbiting Pluto, bringing the planet’s retinue of known satellites to three. The new moons orbit about 27,000 miles (44,000 kilometers) from Pluto, more than twice as far as Charon, Pluto’s other satellite. They are 5,000 times dimmer than Charon. The new moons are between 30 and 100 miles (45 to 160 kilometers) in diameter while Pluto is 1,430 miles wide and Charon’s diameter is about 730 miles.
Preliminary observations suggest they are in circular orbits around Pluto and in the same plane as Charon.
The moons are catalogued as S/2005 P1 and S/2005 P2 for now. Once they are confirmed, the discoverers will suggest names, to be approved by the International Astronomical Union.
The moons were found using the Hubble Space Telescope.
Rocket is like a guiter, they both resonate.
When you pick up an acoustic guitar, one of the first things you’ll notice is the body is basically an air chamber. The shape of the chamber is designed to be ‘in tune’ with the sound from the strings. When one plucks the E string and the body of the guitar vibrates, producing “sympathetic” E-frequencies of its own. It is called ‘resonance’ and it’s a big part of what makes a great guitar.
Resonance may be great for guitars, but it can be disastrous for a spacecraft. When the shuttle lifts off, the main engines roar so loudly that a person standing near the pad would be killed—not necessarily by the heat of the exhaust, but by the sound of the engines. The engines “strum” the spacecraft with incredible force. Rumbling sound waves penetrate the shuttle and its cargo, seeking, probing, shaking.
The engines aren’t the only source of sound. After liftoff, the rocket rips its way through the atmosphere en route to space. Rushing air creates strong aerodynamic noise, which rattles the ship.
Even in space, the noises don’t stop. Vibrations can ripple through a spaceship when it docks with another ship, or when it fires its maneuvering thrusters. The goal of engineers is to make sure these vibrations die out quickly, before they do any harm. When one strums his guitar, the sound lasts a long time, that’s the sustain. Long-lasting vibrations are encouraged by the fabric of the guitar itself. Notice how the guitar is made of lightweight, flexible wood—a material that likes to vibrate.
Rockets are made of stiffer, heavier materials, that damp resonances and reduce sustain. But that’s not the only trick spacecraft designers use. Sometimes they modify the shape of the rocket, adding supports or filling in empty spots. The purpose: to detune the rocket from itself.
Detuning rockets isn’t easy because, as instruments, they’re much more complicated than guitars. A guitar is constructed from dozens of parts. A typical rocket, on the other hand, is made of thousands of parts. The space shuttle famously contains more than a million components. All these pieces vibrating together produce a cacophony of frequencies ranging from subsonic waves that only an elephant could hear to high-pitched whines akin to fingers scratching a blackboard.
Which frequencies might do the most damage? What parts of the spacecraft are most vulnerable to resonance? And how do you de-tune this complicated instrument?
To answer these questions, NASA engineers have developed “sound studios” for spacecraft. By observing the response of “test articles” to the sounds, engineers can discover resonances and make changes to squelch them.
Acoustic testing has been a regular part of rocket design since the Apollo program four decades ago.
A close flyby of Saturn’s grayish moon Dione reveals it is a mature, frigid world with hints of tectonic activity. The U.S.-European Cassini spacecraft flew within 310 miles (500 kilometers) of the Dione’s pale surface last week, showing it possessed a heavily cratered surface but no presence of an atmosphere.
Cassini scientists compared the frozen Dione to another Saturn moon, Enceladus, which recently was found to have active ice volcanoes and a significant atmosphere. Enceladus is the up-and-coming moon, complete with a recently active history, while Dione is the older, more mature moon.
Vandenberg Air Force Base is a sprawling space and missile hub, located on California’s Central Coast. Situated northwest of Los Angeles, the base is larger in acreage than the nearby cities of Lompoc, Santa Maria and Guadalupe combined. Vandenberg supports a population greater than 18,000, comprised of military, family members, contractors, and civilian employees.
The base was originally established in 1941 as the US Army’s Camp Cooke. The facility served as a training center for armored and infantry troops through World War II and again in the Korean War. The base was transferred to the US Air Force in 1957 and began its transformation into a space and ballistic missile test facility. The year after, the base was renamed after General Hoyt S. Vandenberg, second chief of staff of the Air Force.
In 1972, Vandenberg was selected as the West Coast Space Shuttle launch and landing site. Space Launch Complex 6 (SLC-6, pronounced as "Slick Six"), originally built for the abandoned Manned Orbiting Laboratory project, was extensively modified for Shuttle operations. SLC-6 was nearly ready for its first Shuttle launch (STS-62A) when the Challenger disaster grounded the program and set in motion a chain of events that led to the cancellation of all West Coast Shuttle flights. It has since been rebuilt to support polar-orbit satellite launches.
Operated by the Air Force Space Command’s 30th Space Wing, Vandenberg AFB is the only military base in the United States from which unpiloted government and commercial spacecraft are launched into polar orbit. It is also the only site from which intercontinental ballistic missiles (ICBMs) are routinely test fired into the Pacific Ocean.
For the 368th and last time, the United States launched a Titan rocket into space Wednesday. The blastoff of the 16-story, unmanned Titan IV signaled the end of an era that began in 1959, as the U.S. military converts to cheaper space boosters.
The last Titan carried a secret payload for the National Reconnaissance Office, which oversees the nation’s spy satellites.
Titan’s past included many high-profile missions, including boosting Gemini manned spacecraft into orbit in the mid-1960s as preparation for the Apollo moon landings.
The workhorse rocket, originally designed as a weapon-bearing intercontinental ballistic missile for the Cold War, also sent many scientific craft on their way to Mercury, Mars and the outer planets.
Inadequate methods of applying and repairing foam on the space shuttle’s fuel tank probably contributed to the dangerous loss of a chunk of the insulation during Discovery’s launch 2 months ago, a NASA investigation team concluded Friday. So much work is needed to understand the problem and correct the deficiencies that shuttle flights are on hold until at least May, and possibly even next summer.
NASA’s Richard Gilbrech, head of the investigation team, said no one may ever know exactly what caused a 1-pound, 3-foot section of foam to break off Discovery’s external fuel tank in late July. It was a scary repeat of what happened during Columbia’s doomed flight in 2003.
Another possibility is that the one-inch layer of underlying foam may have cracked because of thermal stresses, causing the layer on top to pop off.
NASA already has introduced new techniques for applying foam and is limiting workers’ access to vulnerable areas.
Europe’s Venus Express will blast off aboard a Russian rocket from Baikonur Cosmodrome in Kazakhstan on 26 October. After about five months, Venus Express will reach its target and enter an elliptical polar orbit using science instruments to study the planet from space. The mission lasts two Venusian days, equivalent to about 500 of our own.
In the most comprehensive study of the Venusian atmosphere ever, Venus Express will address many open questions:
China’s second manned mission Shenzhou 6 flew 2 million miles in 115 hours and 32 minutes in space. The Shenzhou 6 is a modified version of Russia’s Soyuz capsule. China also bought Russian technology for spacesuits, life-support systems and other equipment. But space officials say all the items launched into orbit were Chinese-made.
China hopes to conduct a spacewalk in 2007, develope the ability to rendezvous and dock with other spacecraft. It also might recruit women into its next group of astronaut candidates.
The government already has announced plans to land an unmanned probe on the moon by 2010 and eventually send up an orbiting laboratory.
China said last year it would launch a moon-orbiting satellite in 2006. The 2-ton Chang’e satellite would orbit at least a year and record three-dimensional images of the lunar surface.
The lunar program — named Chang’e after a legendary Chinese goddess who flew to the moon — includes plans to land a vehicle by 2020 that would collect soil samples and conduct other tests, possibly in preparation for a manned moon base.
Russia’s Mission Control endured a brief but private scare during this week’s return of a Soyuz spacecraft from the international space station with three riders aboard. As the Soyuz descent module headed back to Earth, instruments indicated that air was leaking out — the same kind of failure that killed three cosmonauts in June 1971 on their way home from the world’s first space station, Russia’s Salyut 1.
It remained to be seen whether the air leak was real, or whether there was only a failure in the pressure sensor. A real pressure leak, apparently the first in more than 30 years, would raise questions about the airtightness of the Soyuz TMA-7 spacecraft that was launched Oct. 1 and is currently docked to the station as a landing vehicle for the space station’s current crew members, William McArthur and Valery Tokarev.
1956: China opens its first Missile and Rocket Research Institute.
1960: China develops its first rocket, aided by Russian scientists. It is the first of a series of rockets, all named CZ (for changzheng, or "long march").
1964: Four albino rats, four white mice and 12 tubes of biological samples are put on a T-7A-S rocket, which reaches an altitude of 70 kilometres.
1970: On 24 April, China becomes the fifth country in the world to send a satellite into orbit, as the DFH-1 is lifted into space on board a Long March rocket. The Soviet Union launched the first-ever satellite, Sputnik, in 1957.
1984: A new launch site opens in Xichang, in south-western China’s Sichuan province.
1988: Another launch site opens at Taiyuan in north China.
1995: China’s space programme suffers a setback when a CZ-2E rocket explodes after take-off from Xichang, killing at least six people on the ground.
1996: China signs an agreement for the acquisition of Russian space technology.
1999: The Shenzhou spacecraft is launched on 20 November on a CZ-2F rocket and returns to Earth after 14 orbits. It carries several kilograms of biological samples.
2001: Shenzhou II blasts off on 9 January, carrying microbes and several small animals. The capsule returns to Earth on 16 January, touching down in the Inner Mongolia region.
2002: Shenzhou III is launched on 25 March in the presence of President Jiang Zemin. On 1 April, after orbiting the Earth 108 times, the craft returns. Shortly afterwards, Beijing announces plans for a space station. On 29 December, Shenzhou IV is sent into orbit, and returns to Earth six days later.
2003: On 15 October, Shenzhou V blasts into orbit, carrying China’s first man in space, Yang Liwei. He returns after 21 hours and 14 trips around the Earth.
2005: On 12 October Shenzhou VI blasts off for a five-day mission carrying two taikonauts.
Mo'nonymous on New companion of Nep...
Mo'nonymous on New companion of Nep...
Mo'nonymous on New companion of Nep...
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