Where Are The Aliens?

As humanity continues to make heady progress in space exploration, the question of whether life exists elsewhere in the universe is naturally becoming more pertinent. Of course, by life, we generally mean organisms as sentient and advanced as us, if not more so — not that the existence of other lifeforms as simple as bacteria would not still be amazing.

The debate about extraterrestrial lifeforms is hardly a new one, even if it does have great significance now that we are making great inroads in observing an ever-expanding proportion of the universe. Perhaps one of the most famous participants in the discussion is Nobel Prize-winning Italian physicist Enrico Fermi, who in the 1950s conceived of the Fermi Paradox: If the universe was teeming with intelligent, technological civilizations, where are they?

More to the point, even if we grant that said life has simply not reached Earth yet, why have we not seen evidence of their colonization or arrival elsewhere in the universe? NPR explores the matter further:

The most important thing to understand about Fermi’s paradox is that you don’t need faster-than-light travel, a warp-drive or other exotic technology to take it seriously. Even if a technological civilization built ships that reached only a fraction of light speed, we might still expect all the stars (and the planets) to be “colonized.”

For example, let’s imagine that just one high-tech alien species emerges and starts sending ships out at one-hundredth of the speed of light. With that technology, they’d cross the typical distance between stars in “just” a few centuries to a millennia. If, once they got to a new solar system, they began using its resources to build more ships, then we can imagine how a wave of colonization begins propagating across the galaxy.

But how long does it take this colonization wave to spread?

Remarkably, it would only take a fraction of our galaxy’s lifetime before all the stars are inhabited. Depending on what you assume, the propagating wave of colonization could make it from one end of our Milky Way to the other in just 10 million years. While that might seem very long to you, it’s really just a blink of the eye to the 10-billion-year-old Milky Way (in other words, the colonization wave crosses in 0.001 the age of the galaxy). That means if an alien civilization began at some random moment in the Milky Way’s history, odds are it has had time to colonize the entire galaxy.

In other words, even if the galaxy, let alone the whole universe, is conceivably too big for even an advanced species to explore or propagate, it is not necessarily so big as to preclude any kind of mark left by an intelligent, space-faring race.

Granted, there is no shortage of explanations and counterarguments to this paradox: that the aliens have not reached space-faring capabilities, that for one reason or another they have chosen not to travel beyond their world, etc. But the article goes on to suggest a more unsettling conclusion worth at least considering: maybe we truly are alone out there, at least within our Milky Way galaxy (anything farther than that would be unfathomably unreachable and visa versa).

On the one hand, it’s possible that no other species has ever reached our state of development. Our galaxy with its 300 billion stars — meaning 300 billion chances for self-consciousness — has never awakened anywhere else. We would be the only ones looking into the night sky and asking questions. How impossibly lonely that would be.

On the other hand, it’s also possible that other species have made it to where we stand today. But no one has made it much farther. Say that like a “great filter,” something like war or environmental collapse keeps anyone, anywhere, from reaching beyond our stage of technological development. If that’s true then we, like all who have come before us, are doomed.

Personally, I still like to hold out hope that intelligent life does exist “out there”, or at the very least once did (there is no reason to believe that such a species did not destroy itself or otherwise go extinct from some sort of natural catastrophe). The probability of some sort of organism existing elsewhere in our galaxy seems high, but whether it (or they) is intelligent is apparently still an open question.

What are your thoughts?

The farthest confirmed galaxy observed to date.

Astronomers Reach New Milestone: Farthest Galaxy Ever Measured

The above photo, courtesy of the New York Times, may not look like much, but it represents an amazing achievement in the field of astronomy and in our understanding of the universe. Here’s more from the Times:

The [pictured] galaxy, more than a few billion light-years on the other side of the northern constellation Boötes, is one of the most massive and brightest in the early universe and goes by the name of EGS-zs8-1. It flowered into stardom only 670 million years after the Big Bang.

The light from that galaxy has taken 13 billion years to reach telescopes on Earth. By now, however, since the universe has continued to expand during that time, the galaxy is about 30 billion light-years away, according to standard cosmological calculations.

The new measurements allow astronomers to see the galaxy in its infancy. Despite its relative youth, however, it is already about one-sixth as massive as the Milky Way, which is 10 billion years old. And it is getting bigger, making stars 80 times faster than the Milky Way is making them today. The discovery was reported in The Astrophysical Journal by Pascal Oesch of Yale University and his colleagues.

Imagine what more awaits once even more powerful tools like the James Webb Space Telescope and the Thirty Meter Telescope come into being.

Eleven Images That Capture The Sheer Vastness Of Space

Did you know that you could fit all seven of the other planets in the solar system between Earth and the moon — with room to spare. Note that Saturn and Jupiter, are nine and 11 times as wide as Earth, respectively. It goes to show impressive our landing on the moon was.

Find other facts about how incredibly large and unfathomable space is here.

Hat tip to Vox.com.

If You Thought Hubble Images Were Breathtaking…

…wait until NASA and its international partners launch the James Webb Space Telescope (JWST), which will be 100 times more power than its venerable 25-year-old predecessor. More from Business Insider:

The space telescope will weigh 6.4 tons. JWST’s main mirror will be 6.5 meters (yards) in diameter, three times as large as Hubble’s.

A joint project of NASA, the European, and Canadian space agencies, JWST will carry four instruments, including cameras and spectrometers that can capture extremely faint signals.

Infra-red capability will help it observe distant celestial bodies, and its camera shutter will be able to remain open for long periods, explained Matt Greenhouse, JWST project scientist for the science instrument payload.

“The Webb will have 70 times the light-gathering capacity of Hubble. So the combination of the large size and the infra-red capabilities will allow us to observe this epic of the universe past,” he said in an interview

An official statement by NASA describes the over $8 billion telescope as a “powerful time machine with infrared vision that will peer back over 13.5 billion years to see the first stars and galaxies forming out of the darkness of the early universe.”

Indeed, it is so powerful that may even be able to detect signs of life on distant exoplanets, down to the specific composition of their atmospheres.

Moreover, unlike the Hubble Space Telescope, which circles the Earth, the JWST will be 930,000 miles (1.5 million kilometers) away, at a place called LaGrange Point. That means it will be colder and thus suffer less interference from radiation and its own infra-red light.

The heavy telescope is scheduled to launch October 2018 atop an Ariane 5 rocket, made by the European Space Agency, from French Guiana.

Given the breathtaking images Hubble has given us over the last quarter-century, to say nothing of how much it has advanced our understanding of the universe, it is exciting to imagine what something 100 times as powerful will offer us.

And if NASA can pull something like this off, albeit with help from its foreign partners, imagine what it could do with more funding and public support…

It is also encouraging to see more international cooperation in space exploration. I have noted numerous times before how the technological and financial challenges of space travel necessitate humanity pooling together all its resources and expertise. The JWST will be a strong testimony to that.

The Launching of a Space Milestone: Mir

On this day in 1986, the Soviet Union launched Mir, the first continuously inhabited long-term research station to orbit Earth. Assembled during orbit from 1986 to 1996, it had greater mass than any previous spacecraft at the time, and remained the largest satellite in orbit until 2001, when it was succeeded by the International Space Station (ISS).

Mir

The station served as a microgravity research laboratory where crews conducted experiments in biology, human biology, physics, astronomy, meteorology and spacecraft systems. The goal was to develop technologies that would further permanent human occupation of space.

Mir set the record for the longest continuous human presence in space at 3,644 days, until it was surpassed by the ISS in 2010. It hosted the record for the longest single human spaceflight: Valeri Polyakov spent over 437 days on the station between 1994 and 1995. Mir had the capacity to support a resident crew of three, or larger crews for short term visits.

Polyakov really loves what he does.

Mir was launched as part of an effort to maintain a long-term research outpost in space. While the vast majority its crew was Russian, several international programs made it host to astronauts from the United States, Canada, Japan, and several European nations; the first Syrian and first Afghan in space were Mir visitors. These collaborative efforts were the precursor to the development of the ISS, which evolved from separate U.S., European, and Russian projects.

Following the collapse of the USSR, Mir came under the operation of the new Russian Federal Space Agency (Roscosmos). Although the station was fairly resilient, as evidenced by its impressive lifespan, its age was showing, and Russia at the time could not afford to update it. The station was subsequently decommissioned and deorbited in 2001.

The first of many successors. 

VY Canis Majoris

VY Canis Majoris is the largest known star in the universe, being around one billion times bigger than our sun — which is one million times bigger than Earth — which in turn is already pretty immense. If it were to replace our sun, the star’s surface would reach up to Jupiter or Saturn. Imagine how the individual human matches up? We could scarcely register the scale of it all in our minds, much less physically grasp it with our senses.

The following short video further emphasizes how mindbogglingly vast our universe is — and how infinitesimally small we are by comparison.

The Profundity of Space Travel

I’m quite sure everyone imagines space travel to be an experience unlike anything imaginable. The impact it must have on one’s psyche and worldview (no pun intended) is incomparable to any other experience we can conceive of.

Imagine seeing everything we’ve ever known and experienced — the culmination of all histories, lives, and events — within a single frame of view. Imagine being so far away that you could put your hand up and see the Earth as smaller by comparison. It’s no wonder so many astronauts, from what I’ve seen, appear to be so philosophical and worldly.

There is a 20-minute video posted on Upworthy shows breathtaking images and videos of Earth from space, intersected with beautiful ruminations and narratives told by a variety of people, from astronauts and scientists to popular writers and academics. I highly recommend you watch it, as it’s worth every minute.

 

I hope to live to see the day when space travel is as easy as taking a plane. It’s hard to imagine what such a world would be like.

On This Day in History: The First Woman in Space

Fifty years ago today, Valentina Tereshkova became the first woman into space, having been selected from more than 400 applicants and 5 finalists to pilot the Vostok 6, the last mission of the Vostok program. Although Tereshkova experienced nausea and physical discomfort for much of the flight, she orbited the earth 48 times and spent almost 3 days in space. With a single flight, she logged more flight time than the combined times of all American astronauts who had flown before that date.

She was also the first civilian into space; whereas most astronauts and cosmonauts had military backgrounds, Tereshkova, who had humble origins, was employed as a textile worker. She chosen only for her skill and enthusiasm for skydiving, which she pursued as a hobby (she was made an honorary member of the Soviet Air Force after her mission). Talk about a career seque.

Even though there were plans for further flights by women, it took 19 years until the second woman on Earth, Svetlana Savitskaya, flew into space. Tereshkova now lives a quiet and low-key life in Russia, although she is a staple in many science conferences and political functions.

Learn more about her and the history of women in space here.

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Happy 540th Birthday to Nicolaus Copernicus

Happy 540th Birthday to Nicolaus Copernicus (19 February 1473 – 24 May 1543)

A name well-known to students across the western world, Copernicus (19 February 1473 – 24 May 1543) was a Renaissance mathematician and astronomer who formulated a comprehensive heliocentric model, which as opposed to the prevailing geocentric model of the time, placed the Sun, rather than the Earth, at the center of the universe. The model was also one of the first to describe the system’s mechanics in mathematical terms.

Just before his death, Copernicus published is magnum opus, De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres), which is considered a major event in the history of science. It began the Copernican Revolution and contributed importantly to the subsequent emergence of the Scientific Revolution.

In addition to his achievements in mathematics and astronomy, Copernicus was one of the great polymaths of the Renaissance — he was quadrilingual, a jurist with a doctorate in law, physician, classics scholar, translator, artist, Catholic priest, governor, diplomat and economist.