Category: Satellites

Jim Oberg has written a very interesting article at MSNBC.com, commemorating the 50th anniversary of the launch of mankind’s fourth artificial satellite, Vanguard 1. While it is no longer functioning or communicating, it is the oldest satellite still in orbit. Jim says, “Vanguard 1 was the first artificial earth satellite powered by solar cells, and its small suite of instruments provided unprecedented information on Earth’s size and shape, air density and temperature ranges, and the micrometeorite density in space. Tracking its orbit helped geophysicists realize that Earth is not round but slightly pear-shaped, with a slight, symmetric equatorial bulge.”

Jim has a lot of good history included in the article, but most intriguing, Jim reports Vanguard 1 could become the first satellite brought home, for museum display, by a new generation of robotic space vehicles. That would be incredible! Such an attempt would be a demonstration of robotic space vehicles’ capabilty, in addition to providing an Earth orbit (and highly exciting) version of retrieving Gus Grissom’s Liberty Bell 7 from the ocean floor. Do check out Jim’s article.

Jim Oberg, of course, is a noted journalist, author, linguist (sorry, inside joke) and space consultant for NBC News.

Just a quick piece of sad news. SES Americom reported that its AMC-14 satellite failed to reach its orbit on Saturday after it was launched by a Russian Proton Breeze-M rocket. Despite the failure, though, there might be hope that the satellite will be broadcasting HD television eventually.

The company said that the problem happened during the second burn of the fourth stage, and resulted in the satellite – built by Lockheed Martin – not reaching its geostationary transfer orbit.

With this failure, the company has suspended plans to ship the next satellite to the launch site, and its April launch will be postponed until a thorough investigation can be done. Dish Network was originally planning to lease the entire capacity of the satellite to increase the number of high-definition television channels that it broadcasts. They were planning to launch three new satellites in 2008.

It’s not a hopeless situation, however. SES Americom president Edward Horowitz said he’s working with Lockheed Martin engineers to figure out a way to get AMC-14 back into its correct orbit. The downside is that the fuel used to get the satellite into its proper orbit will shorten its broadcast lifetime, since it’ll have less fuel for station keeping.

Original Source: SES Americom News Release

The shoot down of US spy satellite USA 193 was condemned by some quarters of the international community. However, the fact remains, this was a resounding success for the US military. Observers of the operation to destroy the potentially dangerous satellite likened it to “trying to fire a missile through the eye of a needle”. After all, the dead satellite was orbiting at a height of about 250 km, and the satellite-killing missile was fired from a boat; assuring impact with an object the size of a small bus was never going to be easy. But the mission was a success and the satellite disintegrated into bits (no bigger than a football). Now the task of tracking the debris is under way, and the fallout from last months fireworks are impacting the scheduled launch of other space missions…

According to CelesTrak, there are 52 catalogued bits of USA 193 orbiting the Earth. The pieces range in altitude from 167 km (at the closest approach) to over 2,600 km (at apogee – the highest point of orbit) and they are being tracked with great accuracy (pictured above).

The 5,000 pound (2,300 kg) satellite apparently disintegrated into many small pieces of debris, each no bigger than the volume of a football (equivalent to a circle with a diameter of 20 cm). Anything smaller than 10 cm cannot be tracked with any degree of accuracy, so an analysis by CelesTrak (pictured left) shows the upper and lower bounds of debris that can be tracked and how long they are likely to stay in orbit.

As a rule, larger pieces of debris will remain in orbit for longer, whilst the smaller objects will have less momentum to stay above the Earths atmosphere. As can be seen, most of the debris can be expected to burn up through atmospheric re-entry within 30 days, but there is a massive difference in the lifetime of the remaining 10 cm debris when compared with the 20 cm debris. The remaining 5% of large chunks of satellite are projected to stay in orbit for 50 days longer than their smaller cousins.

Tracking these bits of debris is an arduous task, but the monitoring continues. The destruction of USA 193 has influenced the scheduled launch of rockets since February 20th, and disruption is likely to continue should these larger pieces of debris pass through spacecraft launch windows. The launch of a US National Reconnaissance Office NROL-28 reconnaissance satellite last Friday from Vandenberg Air Force Base in California, has been postponed for two weeks until the USA 193 debris poses no threat of collision.

Universe Today coverage of the demise of satellite USA 193:

• US Cruiser Strikes Dead Spy Satellite
• US Planning to Shoot Down Dead Spy Satellite
• US Spy Satellite Could Crash To Earth In February

Original Source: CelesTrak

The zero-gravity of Earth orbit is a massive attraction to developers of new technologies. This highly controlled environment removes one of the key forces acting on experiments here on Earth, therefore allowing new techniques to be tried out. Although it can be great to get a highly sensitive experiment to test new technologies into orbit, the experiments must also be robust enough to cope with the massive forces and vibrations during a rocket launch into space.

The US Naval Academy has announced that two new technologies have succeeded in orbital experiments on board the MidSTAR-1 satellite, signifying these new high-tech methods can indeed be carried out in space, and as an added bonus, they may have revolutionary applications down here on Earth…

The US Naval Academy (USNA) satellite called MidSTAR-1 was launched from Florida’s Cape Canaveral Air Force Station on March 8th, 2007 as a part of the USNA’s Small Satellite Program (SSP). The SSP is intended to send miniature, inexpensive satellites into orbit where experiments and other operations can be carried out. The satellites and experiments are designed, constructed and controlled by officers in the US Navy.

Results from two experiments being carried out on MidSTAR-1 have just been announced, and they appear to be a resounding success. The first experiment uses nanotechnology  to detect dangerous chemical compounds in the air. Almost like a miniature smoke detector, the new method is designed for use in space environments (on board missions such as the International Space Station) as well as counter-terrorism activities here on Earth. The second experiment tests the response of a radiative film (no thicker than a plastic freezer bag) that could be used to regulate the temperature of spacecraft. Both technologies have never been tested in space and both appear to have functioned rather well.

In the nanotechnology experiment, the Nano Chemsensor Unit (NCSU) uses very thin nano-tube material (10,000 times thinner than a human hair) to detect poisonous gases in a space-borne environment, primarily protecting astronauts. In fact, this new detector is only the size of a pencil eraser, but has many times the sensitivity of a household smoke detector. The NCSU performed excellently, detecting the target contaminants repeatedly. It is hoped that tiny detectors such as this will be installed in future NASA missions to detect fuel leaks or contamination by common air pollutants such as nitrogen dioxide. Exposure to the vacuum of space, radiation and vibrations at launch do not seem to significantly affect the prototype sensor. Terrestrial applications of the system include atmospheric monitoring and even explosive residue detection during homeland security exercises.

The second technology to be successfully tested is a thin film that changes its characteristics depending on the amount of electric current that is passed across it. This revolutionary material could be used to “wrap” spaceships so their temperature can be regulated. The film can radiate waste heat away from the body of the spacecraft, or can insulate it, holding the heat inside. The science behind this material is known as electrochromics, and before this mission it had never been tested in space. The material is very lightweight, efficient and uses very little energy, a superb addition to any spaceflight mission. Terrestrial applications of this material include using an electrochromic film to coat buildings, making them energy efficient during the winter, but keeping homes cool during summer. This should reduce the amount of energy required to heat and cool buildings, cutting down on cost and the production of greenhouse gases.

Another exciting use of this film could be to use it to surround future robots exploring the solar system, optimizing the temperature for best performance. Also, this technology would be vital to the energy conservation on future manned Moon and Mars bases.

Whatever the application, these preliminary experiments are proving to be highly successful and may revolutionize some aspects of space- and terrestrial-based technology.

“MidSTAR is the seventh piece of hardware that the small satellite program has flown. It’s by far the most sophisticated and most ambitious. It’s proven to be the most productive and all four experiments operating in space are producing excellent data.” – Billy Smith, Director of the Small Satellite Program.

Source: Science Daily

Officials have confirmed that the US spy satellite, USA 193, has been hit by an anti-satellite missile fired from USS Lake Erie positioned west of the Hawaiian Islands in the mid-Pacific at 10.30pm (US Eastern Time) Wednesday night. Fears of the propellant hydrazine being released into the atmosphere prompted the military response. Although plans for the missile strike were hampered by bad weather, the launch appears to have gone ahead regardless.

The 10.30pm time window was chosen by the US so that should the first attempt fail, a second and then a third attempt could be carried out. The window was only 10 seconds long, and BBC correspondent Jonathan Beale, based in Washington, says this operation was hugely ambitious and likened it to “trying to fire a missile through the eye of a needle.”

It is hoped that the modified Standard Missile-3 (SM-3) successfully destroyed the large orbiting mass, containing 450kg (1,000lbs) of the poisonous propellant hydrazine. The SM-3 does not carry a warhead; it depends on its high velocity and weight to destroy the target. Travelling at a velocity of over 17,000 mph, on impact the missile and satellite should break up, creating debris and hopefully destroying the full fuel tank. Most of the debris is expected to burn up in the Earths atmosphere over the next 15 hours (or two Earth orbits), and all of it is expected to have re-entered over the next 40 days, eliminating the risk of the poisonous fuel falling to Earth. However, at least 24 hours will be needed to assess how successful the strike has been.

In an official statement, the Department of Defence has said, “A network of land-, air-, sea- and space-based sensors confirms that the U.S. military intercepted a non-functioning National Reconnaissance Office satellite which was in its final orbits before entering the Earth’s atmosphere […] At approximately 10:26 p.m. EST today, a U.S. Navy AEGIS warship, the USS Lake Erie, fired a single modified tactical Standard Missile-3, hitting the satellite approximately 247 kilometers (133 nautical miles) over the Pacific Ocean as it traveled in space at more than 17,000 mph.”

The missile strike has prompted anger from both Russia and China, as the nations see it as a provocative manoeuvre by the US, but US officials insist that the missile strike was not intended to showcase their anti-satellite technology and was not used to destroy any top-secret orbital weapon.

Sources: CNN, BBC

The US Navy is planning to shoot down a dead spy satellite that broke down shortly after it was launched in December 2006. Not only are there fears that the large satellite could survive re-entry through the Earth’s atmosphere causing damage and perhaps fatalities, the satellite is also carrying the poisonous hydrazine propellant that could be a health risk if inhaled. Therefore plans are afoot to destroy the craft in orbit rather than letting it fall to Earth some time late February or early March.

This has been a frustrating time for the US military. As previously reported on the Universe Today, one of their most advanced spy satellite systems broke down soon after it was launched into space, leaving mission controllers in the dark as to where the satellite was going. This is bad enough, but if the satellite fell to Earth, it could reveal potentially sensitive secrets about the US spying technology. And not forgetting the potential risk of damage or death should the chunk of high-tech scrap fall to Earth… the US military is now planning to take action rather than leaving it up to gravity to decide where the satellite will crash.

Officially, the reason for the planned shooting down of the craft is not to destroy top secret technology (as most of the sensitive material is likely to burn up) but to prevent deadly fumes from being produced from the propellants the craft has in abundance onboard (after all, it didn’t have much of a chance to use any of its fuel). This is an opportunity for the US Navy to use one of its ballistic missile launchers onboard one of its support vessels. The Arleigh Burke class destroyer, USS Decatur (pictured) underwent ballistic missile launch tests last year, built to intercept incoming missiles high in the atmosphere. The satellite, presumed to be in a low Earth orbit, may be reached by such a missile defence system.

The area affected by the hydrazine should the fuel tanks survive re-entry would cover two football pitches, and if inhaled, would have similar effects to chlorine or ammonia – causing a burning sensation in the lungs. If too much is breathed in, it could prove deadly. A US military general stated that should the plan go ahead, they will take one missile shot and then assess whether a second would be required during a two day window. He also added that the Space Shuttle Atlantis will have landed before any such interception attempt is made.

On Saturday night, the largest US rocket blasted off, carrying a 2.3 tonne Defense Support Program satellite into orbit. This was the second time a Delta IV-Heavy rocket has ever lifted off. With three core boosters strapped together, it’s like three rockets launched at once.

The launch was made even more spectacular because it was held at night. Launched at 0150 GMT Sunday (20:50 EST on Saturday), the 70-metre tall (230 feet) rocket has three separate engines, each of which can generate more than 2,900 kiloNewtons (650,000 pounds) of force. They guzzle a tonne of propellant every second.

On board the rocket was the Defense Support Program 23 spacecraft; the last in a program of Earth observation satellites designed to spot enemy missile launches and nuclear explosions.

Although the Delta IV-Heavy can carry 13 tonnes into a geostationary transfer orbit, it’s not a commercial provider – just military and government satellites. Europe’s Ariane 5 ECA is the most powerful commercial provider, able to blast off with 10 tonnes.

The Delta IV-Heavy first flew back in 2004. Boeing had originally proposed it as the vehicle that could carry the next wave of space exploration vehicles into orbit. In the end, though, NASA decided to go with the new Ares vehicle for its post-shuttle program.

During that previous test flight, the Heavy encountered a problem with its fuel lines, which caused the engines to go out early, and left the rocket lower than its intended orbit.

Just to put the capabilities of the rocket in perspective, though, the Saturn 5 could put out three times the thrust.

Original Source: United Launch Alliance