Looking to the future, NASA and other space agencies have high hopes for the field of extra-solar planet research. In the past decade, the number of known exoplanets has reached just shy of 4000, and many more are expected to be found once next-generations telescopes are put into service. And with so many exoplanets to study, research goals have slowly shifted away from the process of discovery and towards characterization.
Unfortunately, scientists are still plagued by the fact that what we consider to be a “habitable zone” is subject to a lot of assumptions. Addressing this, an international team of researchers recently published a paper in which they indicated how future exoplanet surveys could look beyond Earth-analog examples as indications of habitability and adopt a more comprehensive approach.
Continue reading “Which Habitable Zones are the Best to Actually Search for Life?”
Since the Kepler Space Telescope was launched into space, the number of known planets beyond our Solar System (exoplanets) has grown exponentially. At present, 3,917 planets have been confirmed in 2,918 star systems, while 3,368 await confirmation. Of these, about 50 orbit within their star’s circumstellar habitable zone (aka. “Goldilocks Zone”) , the distance at which liquid water can exist on a planets’ surface.
However, recent research has raised the possibility that we consider to be a habitable zone is too optimistic. According to a new study that recently appeared online, titled “A Limited Habitable Zone for Complex Life“, habitable zones could be much narrower than originally thought. These finds could have a drastic impact on the number of planets scientists consider to be “potentially habitable”.
Continue reading “Complex Life Might Require a Very Narrow Habitable Zone”
On October 30th, 2018, after nine years of faithful service, the Kepler Space Telescope was officially retired. With nearly 4000 candidates and 2,662 confirmed exoplanets to its credit, no other telescope has managed to teach us more about the worlds that exist beyond our Solar System. In the coming years, multiple next-generation telescopes will be deployed that will attempt to build on the foundation Kepler built.
And yet, even in retirement, Kepler is still providing us with impressive discoveries. For starters, NASA started the new year by announcing the discovery of several new exoplanets, including a Super-Earth and a Saturn-sized gas giant, as well as an unusually-sized planet that straddles these two categories. On top of that, NASA recently released the “last lighty” image and recordings obtained by Kepler before it ran out of fuel and ended its mission.
Continue reading “This is Kepler’s Final Image”
In 2018, scientists announced the discovery of a extrasolar planet orbiting Barnard’s star, an M-type (red dwarf) that is just 6 light years away. Using the Radial Velocity method, the research team responsible for the discovery determined that this exoplanet (Barnard’s Star b) was at least 3.2 times as massive as Earth and experienced average surface temperatures of about -170 °C (-274 °F) – making it both a “Super-Earth” and “ice planet”.
Based on these findings, it was a foregone conclusion that Barnard b would be hostile to life as we know it. But according to new study by a team of researchers from Villanova University and the Institute of Space Studies of Catalonia (IEEC), it is possible – assuming the planet has a hot iron/nickel core and experiences enhanced geothermal activity – that this giant iceball of a planet could actually support life.
Continue reading “Geothermal Heating Could Make Life Possible on the Super Earth Planet at Barnard’s Star”
When exploring other planets and celestial bodies, NASA missions are required to abide by the practice known as “planetary protection“. This practice states that measures must be taken during the designing of a mission to ensure that biological contamination of both the planet/body being explored and Earth (in the case of sample-return missions) are prevented.
Looking to the future, there is the question of whether or not this same practice will be extended to extra-solar planets. If so, it would conflict with proposals to “seed” other worlds with microbial life to kick-start the evolutionary process. To address this, Dr. Claudius Gros of Goethe University’s Institute for Theoretical Physics recently published a paper that looks at planetary protection and makes the case for “Genesis-type” missions.
Continue reading “Seeding the Milky Way with Life Using Genesis Missions”
In recent years, the number of extra-solar planets discovered around nearby M-type (red dwarf stars) has grown considerably. In many cases, these confirmed planets have been “Earth-like“, meaning that they are terrestrial (aka. rocky) and comparable in size to Earth. These finds have been especially exciting since red dwarf stars are the most common in the Universe – accounting for 85% of stars in the Milky Way alone.
Unfortunately, numerous studies have been conducted of late that indicate that these planets may not have the necessary conditions to support life. The latest comes from Harvard University, where postdoctoral researcher Manasvi Lingam and Professor Abraham Loeb demonstrate that planets around M-type stars may not get enough radiation from their stars for photosynthesis to occur.
Continue reading “Habitable Planets Around Red Dwarf Stars Might not get Enough Photons to Support Plant Life”
Finding planets is old news, we now know of thousands and thousands of the places. But the terrible irony is that we can only see a fraction of the planets out there using the traditional methods of radial velocity and transits. But the new telescopes will take things to the next level and image planets directly.
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Our newest planet-hunting telescope is up and running at the ESO’s Paranal Observatory in the Atacama Desert in Chile. SPECULOOS, which stands for Planets EClipsing ULtra-cOOl Stars, is actually four 1-meter telescopes working together. The first images from the ‘scopes are in, and though it hasn’t found any other Earths yet, the images are still impressive.
Continue reading “New SPECULOOS Telescope Sees First Light. Soon it’ll be Seeing Habitable Planets Around Ultra-Cool Stars”
How many exoplanets are there? Not that long ago, we didn’t know if there were any. Then we detected a few around pulsars. Then the Kepler spacecraft was launched and it discovered a couple thousand more. Now NASA’s TESS (Transiting Exoplanet Survey Satellite) is operational, and a new study predicts its findings.
Continue reading “Now that TESS is Operational, Astronomers Estimate it’ll Find 14,000 Planets. 10 Could Be Earthlike Worlds in a Sunlike Star’s Habitable Zone”
Gathering detailed information on exoplanets is extremely difficult. The light from their host star overwhelms the light from the exoplanet, making it difficult for telescopes to see them. But now a team using cutting-edge technology at the Keck Observatory has taken a big leap in exoplanet observation and has detected water in the atmosphere of a planet 179 light years away.
Continue reading “Astronomers Detect Water in the Atmosphere of a Planet 179 Light-Years Away”