Jupiter And Earth Imaged Together By NASA’s STEREO/HI-1A / Via

There’s been a rather startling decision today amongst the SETI (search for extraterrestrial intelligence) researchers.

Seth Shostak, senior astronomer at the SETI Institute, announced to his peers at a conference today that it’s time to begin what’s known as ‘active SETI’.

This is when we actively broadcast and effectively ‘alert’ potential neighbors to our presence.

Needless to say, this was a very polarizing conference.

People from Stephen Hawking all the way to science fiction writer David Brin have spoken out against broadcasting our presence into interstellar space.

They both have made comparisons to what happened when industrial civilizations first encountered indigenous peoples. Things never went well for the locals.

David Brin spoke at the conference and said, “The arrogance of shouting into the cosmos without any proper risk assessment defies belief.  It is a course that would put our grandchildren at risk.”

I was initially sidelined by the idea. SETI Institute has never broadcasted into space in an attempt to make humanity’s presence obvious to alien observers. I hadn’t therefore really considered the topic much and shared the same worries as David Brin initially.

In my opinion though Dr. Shostak put an end to that worry:

“I don’t see why the aliens would have any incentive to do that.

Beyond that, we have been telling them willy-nilly that we are here for 70 years now. They are not very interesting messages but the early TV broadcasts, the early radio, the radar from the Second World War - all that has leaked off the Earth.

Any society that could come here and ruin our whole day by incinerating the planet already knows we are here.”

The point is if there’s a hostile and capable alien presence nearby, they would already know about us. The technology required to get to Earth even from the nearest star system is far more advanced than anything we can even dream up at the moment. Detecting our presence at that point is a cake walk.

Active SETI, would be a redundant risk as we’re clearly visible to those significantly advanced civilizations already (if there are any). That we’re here at all still suggests there are none.

To any nearby neighbors stuck on their home planets or solar systems, we are now going to be actively broadcasting messages.

The search is on.

Read more about today’s meeting at BBC World News.

(Image credit: ESO)

What’s Enceladus?

Before we tell you about Enceladus, let’s first talk about our Cassini spacecraft…

Our Cassini mission to Saturn is one of the most ambitious efforts in planetary space exploration ever mounted. Cassini is a sophisticated robotic spacecraft orbiting the ringed planet and studying the Saturnian system in detail.

Cassini completed its initial four-year mission to explore the Saturn System in June 2008. It has also completed its first mission extension in September 2010. Now, the health spacecraft is making exciting new discoveries in a second extension mission!

Enceladus

Enceladus is one of Saturn’s many moons, and is one of the brightest objects in our solar system. This moon is about as wide as Arizona, and displays at least five different types of terrain. The surface is believed to be geologically “young”, possibly less than 100 million years old.

Cassini first discovered continually-erupting fountains of icy material on Enceladus in 2005. Since then, the Saturn moon has become one of the most promising places in the solar system to search for present-day habitable environments.  

Scientists found that hydrothermal activity may be occurring on the seafloor of the moon’s underground ocean. In September, it was announced that its ocean –previously thought to only be a regional sea – was global!

Since Cassini is nearing the end of its mission, we are able to make a series of three close encounters with Enceladus, one of Saturn’s moons.

Close Encounters

On Oct. 14, Cassini performed a mid-range flyby of Enceladus, but the main event will take place on Oct. 28, when Cassini will come dizzyingly close to the icy moon. During this flyby, the spacecraft will pass a mere 30 miles above the moon’s south polar region!

This will be the deepest-ever dive through the moon’s plume of icy spray, where Cassini can collect images and valuable data about what’s going on beneath the frozen surface.

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SpaceX “Just Read the Instructions” droneship ready for Sunday launch & landing attempt http://space-pics.tumblr.com/ source:http://imgur.com/r/space/pANdna4

Curiosity moved approximately 8.0m ESE (119º) on Sol 1151. Quick stitch of the available end-of-drive Navcams. More info to follow

http://space-pics.tumblr.com/

There Will Be A Supernova In The Sky In 2016

A supernova will appear in the sky in the first few months of 2016, according to astronomers working on the Hubble Space Telescope. The prediction is possible because they first saw the star explode in 2014 in a gravitationally lensed galaxy, which will make it visible again next year.

Gravitational lenses happen when a massive object (or objects such as a cluster of galaxies) magnifies and distorts the light of background galaxies. In this case, the galaxy cluster is so massive that it deforms space and time so that it acts like a gigantic magnifying glass.

Sometimes, these distortions produce multiple images of the same object. Although they belong to the same galaxy, the images we see were not emitted at the same time. Because light travels at a finite speed, photons will take a different amount of time to travel around the massive object depending on the path they follow – with some routes taking longer than others.

The supernova explosion that we will see in 2016 is a re-run of the 2014 one, known as the Refsdal Supernova. It was generated in a galaxy nine billion light-years away, and the lens is created by a massive galaxy cluster, called MACS J1149+2223, five billion light-years from us.

Read more ~ IFL Science

Image: This image shows the appearance of the Refsdal Supernova. The middle circle shows the predicted position of the reappearing supernova in early 2016.    Credit: NASA/ESA/HST  

In a real vector space, such as R, corresponding concept in an caffeine space. [2880x1800] http://space-pics.tumblr.com/

launched eighteen years ago, the cassini orbiter is set to crash in to saturn next september, ending its mission to collect data, including these true colour images, on saturn and it’s moons and rings. saturn’s main rings, composed mostly of ice, are thought to have formed only a few hundred million years ago, long after the planet, and the solar system itself, were birthed some four and half billion years ago. 

though a hundred and seventy million miles in diameter, the main rings are only half a mile thick, with the brighter bands showing areas of greater density, and the darker, less dense areas swept relatively clear by the gravity of saturns’ moons - clear enough, anyways, for the cassini orbiter to pass through one of the gaps basically unscathed.

there is no consensus on how the rings were created, but a medium sized moon, either shattered by a meteor or pulled apart by the planet’s gravity, would account for the entire mass of the rings. there is, however, more of a consensus that in about fifty million years, saturn’s gravity will have pulled in the rings and swallowed them up. (but at least mars should have a ring by then.) 

saturn has over forty moons, including one found within a ring gap. these photos show the distant rhea and titan - the latter of which is larger than mercury and has its own atmosphere and hydrocarbon lake - and the inner most mimas and enceladus - the latter being notable for its encompassing liquid ocean of water and geothermal activity.  

I can’t believe Mars has more water than California.

Mostly Mute Monday: The Glory of Saturn’s Rings

“Saturn is remarkable in a number of ways; among all the planets we know of, it’s the least dense, and also the only one with a spectacularly visible set of rings. Composed of icy, dust-like material, these rings are not solid at all, but made up of particles that pass each other, stick together briefly and then fly apart once again.

Snowballs and planetesimals coalesce, only to be torn apart by tidal forces exerted by Saturn and its passing moons. Gaps in the inner rings are caused by the gravitational presence of moons themselves, while many of the outer rings — like Saturn’s E-ring, below — are actually caused by the moons themselves.”

From their discovery in the 1600s, Saturn’s rings have been a source of wonder and puzzlement to skywatchers everywhere. The only ring system visible through most telescopes from Earth, Saturn’s main rings at more than 70,000 km long, yet no more than 1 km in thickness. Once thought to have only two gaps in them, the Cassini spacecraft has revealed over a thousand, teaching us that Saturn’s rings are likely as old as the planet itself, and will likely continue to exist for as long as our Sun shines.

10 Intriguing Worlds Beyond Our Solar System

In celebration of the 20th anniversary of the first confirmed planet around a sun-like star (aka exoplanet), a collection of some interesting exoplanets has been put together. Some of these are rocky, some are gaseous and some are very, very cold. But there’s one thing each these strange new worlds have in common: All have advanced scientific understanding of our place in the cosmos. Check out these 10 exoplanets, along with artist’s concepts depicting what they might look like. For an extended list of 20 exoplanets, go HERE. 

1. Kepler-186f

Kepler-186f was the first rocky planet to be found within the habitable zone – the region around the host star where the temperature is right for liquid water. This planet is also very close in size to Earth. Even though we may not find out what’s going on at the surface of this planet anytime soon, it’s a strong reminder of why new technologies are being developed that will enable scientists to get a closer look at distance worlds. 

More Info

2. HD 209458 b (nickname “Osiris”)

The first planet to be seen in transit (crossing its star) and the first planet to have it light directly detected. The HD 209458 b transit discovery showed that transit observations were feasible and opened up an entire new realm of exoplanet characterization.

More info

3. Kepler-11 system

This was the first compact solar system discovered by Kepler, and it revealed that a system can be tightly packed, with at least five planets within the orbit of Mercury, and still be stable. It touched off a whole new look into planet formation ideas and suggested that multiple small planet systems, like ours, may be common.

More info

4. Kepler-16b

A real-life “Tatooine,” this planet was Kepler’s first discovery of a planet that orbits two stars – what is known as a circumbinary planet.

More info

5. 51 Pegasi b

This giant planet, which is about half the mass of Jupiter and orbits its star every four days, was the first confirmed exoplanet around a sun-like star, a discovery that launched a whole new field of exploration.

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6. CoRoT 7b

The first super-Earth identified as a rocky exoplanet, this planet proved that worlds like the Earth were indeed possible and that the search for potentially habitable worlds (rocky planets in the habitable zone) might be fruitful.

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7. Kepler-22b

A planet in the habitable zone and a possible water-world planet unlike any seen in our solar system.

More info

8. Kepler-10b

Kepler’s first rocky planet discovery is a scorched, Earth-size world that scientists believe may have a lava ocean on its surface.

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9. Kepler-444 system

The oldest known planetary system has five terrestrial-sized planets, all in orbital resonance. This weird group showed that solar systems have formed and lived in our galaxy for nearly its entire existence.

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10. 55 Cancri e

Sauna anyone? 55 Cancri e is a toasty world that rushes around its star every 18 hours. It orbits so closely – about 25 times closer than Mercury is to our sun – that it is tidally locked with one face forever blistering under the heat of its sun. The planet is proposed to have a rocky core surrounded by a layer of water in a “supercritical” state, where it is both liquid and gas, and then the whole planet is thought to be topped by a blanket of steam. 

More info