Universe Today

February 11, 2008December 26, 2015 by Tammy Plotner

Celebrate Valentine’s Day With Eros!

It’s a day meant for celebrating love, and what better way to mark the occasion than to take a look at asteroid Eros! While its mythical name is fitting of the holiday, exploring the famous asteroid went into history on February 14, 2000 when the NEAR spacecraft was successfully inserted into orbit around 433 Eros, becoming the first artificial satellite of an asteroid – an asteroid you can visit with just a telescope!

The Near Earth Asteroid Rendezvous mission had begun its journey on February 17, 1996 as the first of NASA’s Discovery missions to rendezvous with asteroid 433 Eros. During the journey to Eros, NEAR flew within 1212 kilometers of asteroid Mathilde on June 27, 1997 and was to continue onto Eros and obtain orbit in December of 1998. But, as luck would have it, a computer malfunction stopped the rendezvous burn of NEAR’s bipropellant engine and it flew past the asteroid on December 23, 1998. Mission operators quickly reprogrammed the spacecraft to obtain scientific flyby information and set up an orbit that would carry NEAR back to Eros in February 2000.

On the first Valentine’s Day of the new millennium, NEAR went into operation again about an hour after reaching its orbital destination and sent its own Valentine card back towards Earth – the first images of an asteroid taken from an orbiting spacecraft. Features as small as a 330 meters came to life and notably a prominent, sharp-rimmed crater which may have been caused by an impact. Inside the crater walls are subtle variations in brightness that hint at some layering of the rock in which the crater formed. Narrow grooves that run parallel to the long axis of Eros cut through the southeastern part of the crater rim. A house-sized boulder is present near the floor of the crater which appears to have rolled down the bowl-shaped crater wall. A large number of boulders are also seen in other areas of the old asteroid’s heavily cratered surface.

After a year orbiting Eros, NEAR was about out of fuel. Only designed to orbit the asteroid, the spacecraft wasn’t equipped to land and the plan was to simply let it eventually crash onto the surface. Having met all of its research objectives, scientists had a developed fondness for NEAR project and decided to try to land – a procedure which would allow them to test complex maneuvers and get close-up pictures of the surface. These pictures would allow scientists to see objects as small as 10 cm in diameter. The command was given and NEAR slowed its circular orbit and executed a series of braking turns as it approached the surface. The landing site was in the saddle-shaped middle of the asteroid where temperatures vary from 100 C during the day to -150 C) at night – a day that last less than five and half hours! Although the weak gravity only provided an escape velocity of a mere 22 mph, it held the survival ticket of the automobile-sized NEAR on February 12, 2001. Then the probe made space history by successfully landing atop the space rock, more than 316 million kilometers from Earth.

Why not celebrate this Valentine’s Day Anniversary by taking a look at Eros yourself? The 33 kilometer long, 13 kilometer diameter rock is the second largest near-Earth asteroid and is easily seen in larger backyard telescopes. Holding an average magnitude 11.5, you’ll find Eros hanging out in the circlet of Pisces just after sunset. For those with GoTo telescope systems or setting circles, finding Eros is as easy as entering RA 23h 20m 11s Dec 3Â°2’13”! Enjoy your journey to Eros tonight… and wish NEAR a happy anniversary!

February 10, 2008December 26, 2015 by Ian O'Neill

Video of Space Shuttle Atlantis (STS-122) Pitch Maneuver Prior to ISS Docking

In a superb video released by NASA, the Space Shuttle Atlantis’ 360 degree pitch maneuver is captured prior to docking with the International Space Station (ISS) on Saturday. Atlantis’ mission to the station is to deliver and install the European Space Agency’s (ESA) Columbus science laboratory to the station tomorrow (Monday) despite the first spacewalk being postponed due to an undisclosed medical problemÂ with one of the STS-122 astronauts, Hans Schlegel.

It is always amazing to witness the Space Shuttle in Earth orbit, especially when carrying out docking maneuvers or maintenance tasks. With the help of the crew on-board the ISS in the Russian Zvezda service module (pictured), Space Shuttle Atlantis’ rendezvous pitch maneuver (RPM) is videoed before the shuttle began its final approach to the station yesterday (Saturday). The maneuver, where Atlantis performs a “backflip” at a rate of three quarters of a degree per second, exposes the shuttle’s heat shielding on its underside. The ISS crew could then take a series of high-definition photographs to see if there was any damage to the protective layer.

Watch the 9-minute long NASA video of the whole pitch maneuver sequence (includes communication to and from STS-122)
Watch the BBC high-speed footage of the pitch maneuver (standalone Windows Media format, no sound)

A small protrusion of Atlantis’ thermal blanket was discovered on Friday (8th Feb.) during a standard arm checkout and payload bay survey (pictured), but it is not believed to be a problem after the more detailed survey from the RPM.

Space Shuttle Atlantis finally made it into space after a series of delays. It was launched on Thursday (7th Feb.), and you can see the launch in another NASA video (from lift-off to booster rocket separation). Always exciting to watch…

The new Columbus module will be prepared for installation at 9:35am on Monday by Mission Specialists Rex Walheim and Stanley Love during a space walk. Their first task will be the installation of the Power Data Grapple Fixture on the new module, allowing the ISS robotic arm to grab the laboratory and position it at the station’s Harmony module. We will be watching the events as they unfold…

Sources: BBC, NASA

February 9, 2008December 26, 2015 by Ian O'Neill

Building a Moon Base: Part 2 – Habitat Concepts

Plans are afoot to build a manned base on the Moon. As you probably would have guessed, there are quite a few hazards and dangers with sending humankind back to establish lunar “real estate”. However, once our intrepid lunar colonists begin to build, the hazards will become less and development will accelerate. This is all very well, but how will we gain that first foothold in the lunar regolith? What will be the best form of habitat structure that can be built to best suit our needs? These questions have some obvious and not-so-obvious answers from the structural engineers already publishing their ideas and building prototypes…

In Part 1 of this mini series on “Building a Moon Base”, some of the dangers facing astronauts and future colonists were outlined. Moon dust could (in all probability) be a health risk, micrometeorites and other speeding projectiles could burst pressurized structures, highly energetic particles from the Sun could irradiate unprotected settlements, damage to machinery could be caused by the vacuum… generally a mixed bag of bad news. But if anything else, we humans have the ability to beat the odds and succeed (if politics and finances allow of course!). This second installment deals with the habitat structural concepts that are being planned to best serve the first, interim and permanent settlements on the Moon when we overcome all the odds.

“Building a Moon Base” is based on research by Haym Benaroya and Leonhard Bernold (“Engineering of lunar bases“)

Many types of structure have been proposed for lunar colonies. However, the main focus for mission planners center on cost and efficiency. Structures fabricated on Earth, while viable, would have to be very lightweight to allow for easy launch out of the Earth’s deep gravitational well. It is generally envisaged that the first bases to be established on the lunar surface will be built on Earth, but once a base of operations is set up, with a contingent of human (and perhaps robot) workers/settlers, local materials should be mined and habitats fabricated in-situ (i.e. built on the Moon). Some of the structures currently being considered are detailed below.

Inflatable designs

Inflatable habitats have always been a favorite, optimizing living space whilst using lightweight materials. As the Moon has no atmosphere (apart from some very tenuous gases being “outgassed” from its surface), any habitat would need to be highly pressurized to simulate the terrestrial atmosphere (to approximately 1 atmosphere or 101,325 Pa) and atmospheric gas quantities. Due to the high forces acting outwards (by the maintained gas pressure), structural integrity of an inflatable can be assured. Assuming the membrane of the inflatable is strong enough, risk of depressurization should be low.

There is however a massive problem with inflatables. In an environment as vacuum-like as the Moon’s, there is little protection from micrometeorites (small, natural space rocks or manmade space debris). Catastrophic depressurization could occur if a high velocity projectile causes a weakness in the membrane. There are some solutions, such as covering the inflatable habitats with a layer of protective regolith, and extensive fail-safes will need to be put in place.

One design (pictured left) uses inflatable “pillows” to create a cuboid shape (rather than the more natural spherical shape). Many of these pillows can be aligned and added on to create a growing settlement. They would maintain their shape by using high-tensile beams to battle against the bellowing membrane material. Protection from micrometeorites and solar radiation would be provided by regolith.

Erectables
Classic erectables have been extensively tested and are an established form of construction. With a focus on ease of assembly, one plan involves sending components into a low Earth orbit. A frame can be easily erected and act as a tetrahedral, hexahedral or octahedral shape by which to base the design of a simple habitat module. Once complete, the module could be shipped to the Moon where it will be controlled into a soft landing. This method uses existing technology and may be one of the more feasible concepts of beginning a Moon base. A basic structure could also be constructed on the lunar surface in a similar fashion.

Local materials
Ultimately, it is hoped that a settlement on the Moon will have an infrastructure capable of mining local materials, fabricating basic quantities and constructing structures with little or no input from Earth. This degree of autonomy would be required if a thriving Moon base is to succeed.

However, to maintain airtightness within the habitats, a new form of concrete would need to be manufactured. All components for a lunar concrete mix can be found on the Moon, although water (and therefore hydrogen) will be at a premium. As the Moon is sulphur-rich, a different type of concrete (minus the need for water) may be created to aid with the construction of arced and domed habitats. Some “geotextiles” may also be made via some advanced refining, creating filmy materials to seal habitat interiors.

Building using locally mined materials will most likely be one of the more advanced methods of construction on the Moon, so in the first stages at least, settlers will be dependent on the Earth for support.

Lava tubes
Ancient lava tubes under the lunar surface exist and may be utilized by colonists. Using natural cavern systems will have many benefits, principally that minimal construction would be required. Many advocates for this plan point out there are too many risks associated with above surface structures, why not use natural shelter instead? Lava tubes may be interconnected, allowing sizeable settlements, also they may be easily sealed, allowing for pressurized habitats. Lunar colonists will also be sufficiently protected from micrometeorites and solar radiation.

Rovers

To bridge the gap between an immobile base and a highly mobile rover, the first base may consist of settlers living and traveling in a roving Moon base. In fact, many designers suggest this solution may be a long-term answer to the future of a colony on the Moon. Unlike the current lunar “Moon Buggy” (pictured), future rovers would be large, accommodating several people within a pressurized cabin. Using rovers as a base may negatively affect processes only static, permanent bases can achieve (i.e. farming activities), but a roving base would allow settlers the freedom to move when and where required around the lunar landscape.

“Building a Moon Base” is based on research by Haym Benaroya and Leonhard Bernold (“Engineering of lunar bases“)

February 9, 2008December 26, 2015 by Nancy Atkinson

Medical Problem Delays Spacewalk

A medical issue with a member of the space shuttle crew has forced a change in personnel for the first scheduled spacewalk of the STS-122 shuttle mission to the International Space Station. The switch has also mandated that the spacewalk be delayed one day to Monday. NASA officials would not say which astronaut was experiencing any medical problems, but did confirm that Stan Love has replaced Hans Schlegel for the initial spacewalk.

“There was a medical issue with the crew,” said John Shannon, deputy shuttle program manager. “The flight surgeons do private medical conferences with the crew throughout the mission. The crew called down and asked for one during the rendezvous, which was a little bit of a surprise to us. They talked to the crew members, they understood what the issue was. I will just say it is not going to impact any of the objectives of this mission.”

In video shown on NASA TV, Schlegel showed no noticeable illness as the shuttle crew come on board the ISS after shuttle docking. Reports on news wires suggested that Schlegel lost his voice, but that claim was not corroborated by Shannon.

Communication during the spacewalk would be critical. Schlegel appeared to talk with the ISS crew as he entered the station, and floated easily through the Harmony node. About half of all people who fly in space experience Space Adaptation Syndrome, which include symptoms such as nausea, dizziness and headaches. But citing medical privacy policies, Shannon refused to answer any questions about the nature of the medical issue, or whether Schlegel would be available for the second spacewalk of the mission, now slated for Wednesday.

“You guys can fish all day, but I won’t bite,” Shannon said.

The spacewalk will help install the new Columbus science module, brought up in Atlantis’ payload bay. Installation of the module is the primary goal of this mission.

The shuttle docked at 12:17 pm EST on Saturday. As the shuttle approached the station, the ISS crew took photos of the shuttle to check for any damage to Atlantis. They were asked to take special note of a small tear in the insulation blanket of the Orbital Maneuvering System rocket pod along the tail of the shuttle. Shannon said the tear is probably not critical, but that it’s being looked at.

“Nobody is very excited about this one,” he said. “I don’t expect this to be an issue but the team will continue to work it.”

The insulation blankets on the OMS pods experience temperatures around 700 to 1,000 degrees Fahrenheit during peak heating of re-entry. A similar tear on an earlier shuttle flight was repaired by a spacewalking astronaut using surgical staples. Three spacewalks are planned during Atlantis’ current mission and a staple gun is on board if needed.

On a final note, for any Prairie Home Companion fans out there, the shuttle crew wake-up call on Saturday morning was the Powdermilk Biscuit song.

Original News Source: NASA TV

February 9, 2008December 26, 2015 by Nancy Atkinson

Testing a Europa Probe Prototype

While NASA doesn’t have any definite plans to send a probe to study Jupiter’s moon Europa, many planetary scientists consider the exploration of this enticing moon to be a high priority. Evidence from the Voyager and Galileo spacecraft suggests Europa contains a deep ocean of salty water under an icy outer shell. NASA is, however, helping to fund a prototype of an underwater autonomous vehicle to investigate ice covered lakes here on Earth, to demonstrate if such a vehicle could operate in an environment similar to Europa. The next test of the vehicle will take place Feb. 12-15, 2008 in Lake Mendota on the campus of the University of Wisconsin, Madison.

The Environmentally Non-Disturbing Under-ice Robotic Antarctic Explorer, also known as Endurance, will swim untethered under ice, and collect data to create three-dimensional maps of underwater environments. The probe also will look at the conditions in those environments and take samples of microbial life. Later this year, researchers plan to ship the probe to a permanently frozen lake in Antarctica for more operations. The probe is a follow-up to the Deep Phreatic Thermal Explorer, a NASA-funded project that completed a series of underwater field tests in Mexico in 2007.

“We’re using extreme environments on Earth as our laboratory,” says Peter Doran, associate professor at the University of Illinois at Chicago. “Ice-covered lakes are good, small-scale analogs to what we might find on Europa.”

Mendota Lake is only 25 meters deep, while the lake in Antarctica, West Lake Bonney is 40 meters deep. Scientists believe that Europa’s ocean could be up to 100 kilometers deep.

Hot water drills will bore a hole for Endurance to enter the water. If all goes well, the probe will be tested again in 2009.

But many hurdles remain before an underwater vehicle could possibly head to Europa. Presently, Endurance is too massive to send on interplanetary travel. Scientists will also have to come up with a way to drill through Europa’s icy crust and lower the sub safely through the ice.

And before a probe would be sent to land on Europa, many scientists feel that an orbiting spacecraft would be the best way to study the moon. The Jet Propulsion Laboratory is currently working on a concept called the Europa Explorer which would deliver a low orbit spacecraft to determine the presence (or absence) of a liquid water ocean under Europa’s ice surface. It would also map the surface and subsurface for future exploration.

Original News Sources: NASA Press Release, Washington University Press Release

February 8, 2008December 26, 2015 by Ian O'Neill

Extremophile Hunt Begins in Antarctica, Implications for Exobiologists

An expedition has set off for Antarctica’s Lake Untersee in the quest to find bacteria living in one of the most extreme environments on Earth. The bacteria-hunting team are looking for a basic lifeform in a highly toxic location. Resembling the chemistry of Mars, moons of Jupiter and Saturn, even comets, the ice-covered lake may hold some clues to how life might survive, thrive even,Â beyondÂ the “normality”Â of our planet.

Lake Untersee is a strange place. For starters, it is always covered in ice. Secondly, the water’s pH level is so alkali that it resembles bleach rather than regular lake water. And third, it produces methane on a scale that dwarfs any other source on Earth. In fact, the chemistry of this terrestrial location has been likened to the high alkalinity, high methane environments on Mars, frozen moons and comets in our solar system neighborhood.

We already know that extreme life can thrive in the superheated conditions along volcanic vents in the oceans and they can live quite happily in nuclear reactors. Some bacteria areÂ content to be frozen for over 30,000 years before they are thawed to continue life as if nothing had happened. So theÂ search continues… can life thrive in conditions where the pH (a measure of a substances acidity or alkalinity) is considered to be toxic to life? The head scientist of the Antarctic team, Richard Hoover of NASA’s Marshall Space Flight Center, believes that although we consider life that we know to thrive in the “normal” conditions we know and experience ourselves, this may not be the “norm” for life elsewhere in the cosmos.

“One thing we’ve learned in recent years, is that you don’t have to have a ‘Goldilocks’ zone with perfect temperature, a certain pH level, and so forth, for life to thrive.” – Richard Hoover.

The team of US, Russian and Austrian scientists hope to identify additional extreme bacteria to add to their impressive accolade of discoveries. So far, previous teams headed by Hoover have found new species and genera of anaerobic microbial extremophiles in the ice and permafrost of Alaska, Siberia, Patagonia, and Antarctica. Now they hope to find life that is hardy enough to deal not only with the extreme cold of the Antarctic, but also with the “normally” poisonous pH and high methane in Lake Untersee. This will characterize the signature of extreme life, a great help to exobiologists when results come in from future life-hunting missions to Mars and other planetary bodies.

“With our research this year, we hope to identify some new limits for life in terms of temperature and pH levels. This will help us decide where to search for life on other planets and how to recognize alien life if we actually find it.” – Hoover.

Source: Physorg.com

February 8, 2008December 26, 2015 by Tammy Plotner

Asteroid Occulation Alert – Observers Wanted!

According to this morning’s recent alert by Dr. David Dunham of IOTA, observers throughout the Americas, and even westernmost Europe, have a chance to observe an occultation of an 11.3-magnitude star in Gemini by far-flung 20000 Varuna on Sunday night, February 10-11, 2008. This trans-Neptunian object (TNO) may be as large as 1,000 kilometers across.

Those in South America are especially encouraged to try to observe this event, since they have the highest probability for an occultation. The nominal path misses the Earth to the south, but the real uncertainties in the prediction are hard to assess, as Steve Preston (International Occultation Timing Association) notes. So there’s a chance for an event even in North America.

Occultations of stars this bright by such large TNOs are quite rare; so far, none beyond those by Pluto/Charon have been observed. Even if an occultation by Varuna doesn’t occur, there could be an occultation by a possible satellite of Varuna.

Closest approach is at 4:26 Universal Time on February 11th in South America, and about 4:30 UT in North America. The formal uncertainty (1 sigma) in the time is about 5 minutes, but you should be prepared for at least a 3-sigma event. I would recommend monitoring/recording the star for at least 20 minutes before and after the predicted time for your station. If an occultation occurs, there will be a 9-magnitude drop lasting about 43 seconds for a central event. The star to be occulted is TYC 1913-00670-1 at right ascension 7h 18m 50.1s, declination +25Â° 43′ 19″ (equinox 2000.0). It lies 2.5Â° SSW of 5th-magnitude Iota (?) Geminorum and 1.3Â° WNW of 6th-magnitude 57 Geminorum. Detailed finder charts of different scales are on the event are located here. The site also has a view of the Earth as seen from Varuna that can be used to estimate your time of closest approach, as well as the altitude of the event above your horizon. Brian Skiff (Lowell Observatory) notes that the star to be occulted may be slightly fainter than given above, magnitude 11.9 rather than 11.3.

For more about observing occultations in general, check these articles – Reporting Your Observations. For occultations of stars by asteroids, we have special report forms (.xls versions preferred, but plain-text forms are available as well) here. Once you complete one of these forms, please send it to IOTA’s e-mail address for reporting asteroid-occultation observations. Additional resources for reporting your observations are available at the website of the North American Asteroid Occultation Program. Many thanks to Dr. David Dunham of IOTA for providing the information and please spread word of this event. Good luck with your observations!

February 7, 2008December 26, 2015 by Nancy Atkinson

STS-122 Space Shuttle Mission Rockets to Space

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Defying a bleak weather forecast, space shuttle Atlantis rocketed into space on Thursday, February 7, on its way to the International Space Station with a new science laboratory. The STS-122 mission had been delayed by a faulty fuel sensor, and was originally scheduled to launch last December. But today there were no problems with the sensor during fueling and the shuttle lifted off flawlessly at 2:45 p.m. EST. On board is a seven member crew and the European Space Agency’s $1.9 billion Columbus science module, Europe’s main contribution to the ISS. Atlantis will rendezvous with the station on Saturday, Feb. 9. The launch came seven years to the day after Atlantis carried NASA’ science laboratory named Destiny to the space station.

“It was a pretty clean launch,” astronaut Jim Dutton radioed the shuttle crew from mission control following the launch. “We did see, at about MET 2:13 (two minutes and 13 seconds after launch) a few piece of debris, they think at least three, that came off inboard of the LO2 (liquid oxygen) feedline just aft of the starboard bipod leg. The debris assessment team indicated they didn’t identify an impact at the time and it’s obviously under evaluation.”

The crew of Atlantis will now check out its systems and inspect the heat shield while chasing down the space station. There will be three spacewalks during the flight so astronauts can attach the Columbus lab and connect its power and fluid lines.

Atlantis’ liftoff came despite concerns that a weather front would interfere with the launch. But the weather cooperated for an on-time launch.

Installing Columbus, named after the 15th-century Italian explorer, is the main task for the 121st space shuttle mission.

“Columbus has discovered a new world, and I think that with Columbus we are discovering a totally new world,” Jean Jacques Dordain, ESA’s director general, said after the launch.

Atlantis’ seven-member crew includes two Europeans, Germany’s Hans Schlegel and France’s Leopold Eyharts. US astronauts are Commander Steven Frick, pilot Alan Poindexter, and mission specialists Leland Melvin, Rex Walheim, and Stanley Love.

“It’s great to have two laboratories in space,” said Bill Gerstenmaier, NASAâ€™s associate administrator for space operations.

The mission is scheduled to last 11 days.

Original News Source: NASA Press Release

February 7, 2008December 26, 2015 by Fraser Cain

Deep Impact Begins Searching for Extrasolar Planets

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NASA’s Deep Impact completed its main mission. Back in July 2005, the spacecraft’s impactor carved a hole great big hole out of Comet Tempel 1, helping scientists study what lies beneath its surface. But now its time for the spacecraft to re-enter the space workforce and help discover alien worlds.

NASA recently announced that they had extended Deep Impact’s mission to fly past another comet. This time it’ll be Comet Hartley 2 on October 11, 2010. Just like the previous mission, Deep Impact – now renamed EPOXI – will be studying the surface of the comet with its suite of scientific instruments.

But between now and then, the spacecraft has some time to kill. So astronomers searching for extrasolar planets are calling it into service.

The spacecraft will be focusing its largest telescope at five stars, hoping to catch a glimpse of a planetary transit. This is where a planet dims the light from its parent star as it passes in front.

EPOXI Deputy Principal Investigator Dr. Drake Deming of NASA’s Goddard Space Flight Center in Greenbelt, Md explains the technique:

“When the planet appears next to its star, your telescope captures their combined light. When the planet passes behind its star, your telescope only sees light from the star. By subtracting light from just the star from the combined light, you are left with light from the planet,” said Deming, who is leading the search for exosolar worlds with Deep Impact. “We can analyze this light to discover what the atmospheres of these planets are like.”

This search for extrasolar planets has already begun. Deming and his team directed EPOXI to begin making observations on January 22, 2008. It’s looking at stars which are already known to have transiting planets. The hope is that these stars actually contain multiple planets. Since planets seem to orbit on the same plane, if one passes in front of the star, the rest should too. Even if the planets don’t pass perfectly in front of the star, the spacecraft might be able to detect them from the gravitational influence they have on light coming from the star.

EPOXI will be looking for transiting planets down to the size of Earth, orbiting some of our closest neighboring stars.

Original Source: NASA News Release

February 7, 2008December 26, 2015 by Ian O'Neill

Are we sending a bit too much information into the cosmos?

On Monday (February 4, 7 pm EST) NASA’s Deep Space Network (DSN) sent a transmission toward the North Star, Polaris. The transmission sent was the song “Across the Universe” by the Beatles intended for any sufficiently advanced extra terrestrial life to listen to. Although this is a nice gesture and may nurture Beatles fans beyond our solar system, some scientists have expressed concerns for advertising our planet’s location to the universe, just in case the aliens listening in aren’t that friendly after all…

Scientists attending the Search for Extra-Terrestrial Intelligence (SETI) “Sound of Silence” meeting at Arizona State University in Tempe this week are worried. Their concern focuses on some aspects of the scientific community who want to advertise and educate sufficiently advanced lifeforms beyond Earth about our presence and location in the cosmos. Previous efforts have included information about our biology on the Voyager and Pioneer probes, and a broadcast by the Arecibo observatory in 1974. These attempts at communication plus accidental “leakage” of TV and radio signals can all travel vast distances through space and perhaps be received by aliens.

The main argument against trying to communicate with other civilizations is the possibility that if there are aliens out there listening in, then perhaps they might not be friendly. By giving away our location, critical facts about our society, biology and intelligence, we have already given possible alien aggressors a strategic advantage. This threat is obviously very far-fetched, but sending information about our current state of humanityÂ will be inaccurate when signals are received in hundreds, thousands or millions of year’s time, perhaps putting our future generations in a negative light.

“Before sending out even symbolic messages, we need an open discussion about the potential risks […] It’s very charitable to send out our encyclopedia, but that may short-change future generations.” – Douglas Vakoch of the SETI Institute, Mountain View, California.

Vakoch is not concerned that we are risking an alien invasion any time soon, but does highlight the need to discuss the implications of attempted extra-terrestrial communication in an open scientific forum before acting.

If there are any advanced alien beings out there however, they are keeping very quiet. The purpose of the “Sound of Silence” meeting is to discuss why the SETI project has, thus far, not found anything compelling to suggest there are any life forms transmitting their presence to the universe.

“Have we been looking in the wrong place, at the wrong time, in the wrong way?” asks Prof Paul Davies of Arizona State University. “The purpose of this meeting is to brainstorm some radically new thinking on the subject.“

Source: Telegraph.co.uk