Archive for the ‘Habitable zone’ Tag

Proxima B – Life in the Habitable Zone?   26 comments

Historic Potentially Earth-Like World Proxima B

The historic discovery of potentially Earth- like world Proxima-b was announced 24 August 2016. Orbiting Proxima Centauri, a Red Dwarf star in the habitable zone and the nearest star to our own Sun Proxima-b marks not only the closest alien planet ever found but also with the potential to be habitable.

Proxima b

This artist’s impression shows what the sky might look like on Proxima Centauri b if the planet has a surface. The exoplanet orbits the red dwarf star Proxima Centauri, currently the closest star to the solar system at 4.2 light-years. The other two members of the Alpha Centauri triple, Alpha Centauri A and B, would appear in the sky, too.
ESO / M. Kornmesser

 

 

 

 

 

 

 

 

 

If this proves to be the case, then there is no shortage of time for some form of life to originate based on the fact that red dwarf stars such as Proxima Centauri burn for trillions of years.

From the point of view of the average Earth-based visitor stopping by for a summer vacation, Proxima-b runs the risk of being a rather boring holiday resort. The sun-tan would be awesome, not so much so the destruction of the biological cells exposed to the intensely dodgy UV radiation that is present. Combined with the prospect of heavy duty sun-screen to protect from the sun’s constant bombardment of energy flares bouncing around the planetary surface probably wouldn’t be classed as entirely awesome either. On top of which the Proxima Centauri flares would also banish any hope of using mobile phones, tablets, X-boxes or any other such devices thanks to its electronics-disabling qualities. so no ET calling home and definitely no Skype!

Proxima b _Bustle DarkBAlthough it is a tidally locked planet– roasting hot on its star- facing side, freezing cold on the other, there is also enough wind around in the atmosphere to circulate the heat, balancing out the extreme temperatures that would otherwise exist. None-the-less a visit to the the planetary darkside, where it is bathed in perpetual night could prove to be the safest, and possibly the only option.

 

 

 

 

 

 

 

 

 

Unfortunately astronomers are choosing to be particularly pessimistic about this little world following the initial euphoria and have currently decided it is probably a dead, airless rock that will never harbour life due to it’s close proximity sun (20x nearer than Earth to the Sun) creating a risk of it boiling off the water and thereby stripping away the planet’s atmosphere. Researchers its oxygen will be gone in about 10 million years. Life on Earth took billions of years to develop.

Young M Dwarf StarsYoung M dwarf stars can unleash dangerous flares, (“planet-frying radiation”) that strip off atmosphere-forming oxygen spelling doom for closely orbiting planets. NASA Goddard Space Flight Center / S. Wiessinger

 

 

 

 

 

 

 

proxima bImage: NASA Goddard/Conceptual Image Lab

However hope lives eternal. Theoretically it is possible life could advance to endure the high levels of radiation, by altering the worst of Proxima Centauri’s emissions into inoffensive visible light. We know this is plausible, because due to a process known as biofluorescence this —has already happened on many occasions on Earth.

 

 

 

 

 

Ultimately It is expected that the 2018 launch of The James Webb Space Telescope, will provide answers to the critical question of whether there is any chance at all that Proxima b is capable of supporting life.

Proxima b – Habitable ‘Ocean Planet’??

Another possibility is the Proxima b could be an ocean world whose entire surface consists of a liquid ocean. This may bear a similarity to the Jupiter and Saturn moons that are icy worlds with subsurface oceans.

On the other hand the more optimistic researchers suggest that Proxima b may in fact be habitable after all. So don’t put the suitcases back in the attic just yet intrepid cosmic holiday makers! If Proxima b had in reality formed further out from it’s sun than its current position this would also offer a high possibility of there being water. This idea is based on the outer realms of planetary systems being more likely to form ice. If it then moved inwards for a up closer and more personal relationship with its sun then this ice could melt and form seas. Maybe 😉

Sea

Proxima b – A Desert World??

be8a53dc8479400431b0270a3d2ef730But it still seems most likely, according to Victoria Meadows (University of Washington), that this exoplanet is a desert world since the radiation bombarding it would almost certainly have evaporated the majority of the water. This process could have collected the oxygen and hydrogen in the water and created an atmosphere rich in oxygen. Then again it could a 2nd Venus with an atmosphere rich in Carbon Dioxide, or even another Uranus or Neptune.

The Other Closest Habitable-Zone Worlds

If all else fails cosmic holiday makers may wish to try some of the nearbyProxima Wolf 3, potentially habitable exoplanet worlds, for size….: Kapteyn b (13 light-years away) and Wolf 1061 c (14 light-years). Both planets are just over half again as wide as Earth, with minimum masses of 4 to 5 Earths, and both are in their stars’ habitable zones. Wolf 1061 c does not look at all hopeful in terms of habitability. But Kapteyn b looks good. It’s about 3½ times farther from its sun than Proxima b is from its sun so potentially it could be far enough out of reach of its sun’s rather violent output to provide a half decent holiday resort!

 

References:

www.skyandtelescope.com

www.gizmodo.com

www.space.com

www.scinews.com

www.csmonitor.com

Kelper Mission Discovers Twin Earth! (Updated 28th April 2012)   31 comments

 

Gliese 667C – Kelper Mission Discovers Twin Earth!

Billions of potentially habitable alien planets in the Milky Way Smile

Double sunset from Gliese 667C

(Alien Landscape: Artists impression of sunset scene from the Super Earth orbiting the star Gliese 667C (GJ 667C) which is part of the triple star system. The two more distant stars Gliese 667A and Gliese 667B appear in the sky to the right of the image. Astronomers estimate there of tens of billions of small, rocky habitable worlds, in the Milky Way orbiting faint red dwarf stars within their ‘habitable zones,’ where surface water could support life, and dozens within 30 Light Years of Earth. Image Credit: L.Calgada/ESO)

“This was expected to be a rather unlikely star to host planets. Yet there they are very nearby, metal-poor examples of the most common type of star in our galaxy. The detection of this planet and so nearby, and this soon implies that our galaxy must be teeming with billions of potentially habitable rocky planets.” ~ Steven Vogt

Super-Earth Gliese 667C (GJ 667C)

GJ 667C is an M class red dwarf star in a triple star system. The alien ‘super-Earth’ is situated about 22 Light Years away where it is orbiting it’s red dwarf host star in a period of 28 days, and is about 4.5 times larger than Earth. It is temperate enough to allow liquid water to exist on its surface. It is accompanied by orange K class dwarf stars GJ 667A and B.

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GJ 667C receives 90% of light received by Earth, most of which is infra-red, so a higher percentage of incoming energy is absorbed by the planet.

Well worth checking out! Though given the distance it is not likely to be in our lifetime, unless warp speed becomes a reality anytime soon!

“This planet is the best candidate to support liquid water and perhaps life as we know it…”

~ Guillem Anglada-Escude

Artists impression of Super-Earth

About 80% of the Milky Way (160 billion) stars are red dwarfs so it is likely that there are around 65 billion stars with habitable Super Earth’s in our galaxy. About 100 lie within 10 parsecs (32.6 Light Years) of Earth.

“Because red dwarfs are so common – there are about 160 million of them in the Milky Way – this leads us to the astonishing result that there are tens of billions of these planets in our galaxy alone.”~ Dr Xavier Bonfils from Grenoble University in France, who led the international team.

Star spectral classes comparison

THE STUDY – Between February 2008 and April 2009 researchers at the European Southern Observatory, La Sill Observatory in Chile, studied 102 Class M (Red Dwarf) stars situated at a distance of less than 32.6 Light Years away. New planets, new life?New planets are discovered by detecting the subtle wobbles that occur when the planets are orbiting their star. 41% of them are orbiting their stars inside the habitable zone, where they could potentially support life.

GJ 667C was discovered by Astronomers from UC Santa Cruz, Steven Vogt and Eugenio Rivera, led by Guillem Anglada-Escude and Paul Butler of Carniegie Institution for Science.

The HARPS high-precision ‘Planet Hunter’ device works with the 3.6m telescope at the Silla Observatory in Chile to bring us these results.

When the information obtained via a telescope was input into the instruments nine super-Earth planets were detected by astronomers. These included Gliese (GJ) 581 and Gliese(GJ) 667C both of which are within the habitable zones of their stars.

clip_image012However, it should also be remembered that Red dwarf stars are not as super-hot as our star – The Sun. Consequently the super-Earth planets that orbit them must Flares from alien sundo so at a considerably closer range in order to obtain the necessary heat. With their habitable zones in such close proximity to their stars compared to the distance of Earth to the Sun there is a danger that the potential for life could be inhibited by the dangerous X-ray and ultraviolet flares emitted by their stars, which could successfully frazzle any life!

NEWS UPDATE: REPORTS CONFIRM EXISTENCE OF HABITABLE EXO-PLANET! (28TH APRIL 2012)

After re-evaluating information collected back in February, scientists reportedly confirmed on Friday that they had indeed discovered a planet outside of our solar system that is capable of supporting life.

On Friday, the Telegraph published a report confirming the findings.

“Re-analyzing data from the European Southern Observatory, the astronomers found Gliese 667Cc is a solid planet with roughly four and a half times the mass of Earth,” they said, adding that astronomers from the University of Göttingen and the University of California “have calculated the planet receives ten per cent less light from its red dwarf star than the Earth gets from the Sun.”

“It’s the Holy Grail of exo-planet research to find a planet orbiting around a star at the right distance so it’s not too close where it would lose all its water and not too far where it would freeze,” University of California astronomer Steven Vogt said, according to the UK publication. “It’s right there in the habitable zone — there’s no question or discussion about it. It is not on the edge. It is right in there.”

(Source: redOrbit)