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”
There’s no two-ways about it, the Universe is an extremely big place! And thanks to the limitations placed upon us by Special Relativity, traveling to even the closest star systems could take millennia. As we addressed in a previous article, the estimated travel time to the nearest star system (Alpha Centauri) could take anywhere from 19,000 to 81,000 years using conventional methods.
For this reason, many theorists have recommended that humanity rely on generation ships to spread the seed of humanity among the stars. Naturally, such a project presents many challenges, not the least of which is how large a spacecraft would need to be to sustain a multi-generational crew. In a new study, of international scientists addressed this very question and determined that a lot of interior space would be needed!
Continue reading “How Big Would a Generation Ship Need to be to Keep a Crew of 500 Alive for the Journey to Another Star?”
On July 14th, 2015, the New Horizons mission made history when it became the first robotic spacecraft to conduct a flyby of Pluto. On December 31st, 2018, it made history again by being the first spacecraft to rendezvous with a Kuiper Belt Object (KBO) – Ultima Thule (2014 MU69). In addition, the Voyager 2 probe recently joined its sister probe (Voyager 1) in interstellar space.
Given these accomplishments, it is understandable that proposals for interstellar missions are once again being considered. But what would such a mission entail, and is it even worth it? Kelvin F. Long, the co-founder of the Initiative for Interstellar Studies (i4iS) and a major proponent of interstellar flight, recently published a paper that supports the idea of sending robotic missions to nearby star systems to conduct in-situ reconnaissance.
Continue reading “What Would be the Benefits of an Interstellar Probe?”
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”
In 1961, famed astronomer Frank Drake created a formula for estimating the number of extra-terrestrial intelligences (ETIs) that could exist within our galaxy. Known as the “Drake Equation“, this formula demonstrated that even by the most conservative estimates, our galaxy was likely to host at least a few advanced civilizations at any given time. About a decade later, NASA officially kicked of its search for extra-terrestrial intelligence (SETI) program.
These efforts have experienced a major infusion of interest in recent decades thanks to the discovery of thousands of extrasolar planets. To address the possibility that life may exist out there, scientists are also relying on sophisticated tools to search for telltale indicators of biological processes (aka. biosignatures) and technological activity (technosignatures), which could indicate not only life but advanced intelligence.
Continue reading “NASA’s Technosignatures Report is Out. Every Way to Find Evidence of an Intelligent Civilization”
In their efforts to find evidence of life beyond our Solar System, scientists are forced to take what is known as the “low-hanging fruit” approach. Basically, this comes down to determining if planets could be “potentially habitable” based on whether or not they would be warm enough to have liquid water on their surfaces and dense atmospheres with enough oxygen.
This is a consequence of the fact that existing methods for examining distant planets are largely indirect and that Earth is only one planet we know of that is capable of supporting life. But what if planets that have plenty of oxygen are not guaranteed to produce life? According to a new study by a team from Johns Hopkins University, this may very well be the case.
Continue reading “Even if Exoplanets Have Atmospheres With Oxygen, it Doesn’t Mean There’s Life There”
According to current cosmological theories, the Milky Way started to form approximately 13.5 billion years ago, just a few hundred million years after the Big Bang. This began with globular clusters, which were made up of some of the oldest stars in the Universe, coming together to form a larger galaxy. Over time, the Milky Way cannibalized several smaller galaxies within its cosmic neighborhood, growing into the spiral galaxy we know today.
Many new stars formed as mergers added more clouds of dust and gas and caused them to undergo gravitational collapse. In fact, it is believed that our Sun was part of a cluster that formed 4.6 billion years ago and that its siblings have since been distributed across the galaxy. Luckily, an international team of astronomers recently used a novel method to locate one of the Sun’s long-lost “solar siblings“, which just happens to be an identical twin!
Continue reading “Astronomers Find One of the Sun’s Sibling Stars. Born From the Same Solar Nebula Billions of Years Ago”
They say there’s more than one way to skin an interstellar cat, and in astronomy there’s more than one way to find alien exoplanets orbiting a distant star. With the recent shut-down of NASA’s prolific Kepler mission and its windfall of discoveries, it’s time to look towards the future, and towards alternatives.
Continue reading “The Power of the Wobble: Finding Exoplanets in the Shifting of Starlight”