The Research Staff of the North Carolina Museum of Natural Sciences includes experts in a wide variety of scientific disciplines who conduct exciting research investigations, maintain and expand the Museum’s natural science Research Collections, and participate in the Museum’s public education and outreach mission. Check this blog often to learn about all of the great science happening at the Museum!
by Meg Lowman
If aviation engineers could apply the wisdom of the chimney swift, several troublesome problems of aeronautics could be solved. Pilots, for example, would never have to worry about the amount of gasoline in their tanks. The chimney swift refuels on the wing, spends almost its entire waking life in the air, and never, except by accident, touches the earth.
Every autumn, many millions of birds migrate from northern breeding grounds to equatorial locations. This annual flight is not only extraordinary in terms of time and energy, but also raises questions about the physiological issue of sleep. Some birds migrate long distances, while others only shift regionally. So how do birds rest during migration, and what are the consequences for migratory sleep deprivation?
In 2011, the Swiss Ornithological Institute affixed electronic sensors to alpine swifts to monitor their movements. This species spends summers breeding in Europe, but winters in Africa, many thousands of miles away. Thanks to electronic tagging, scientists found that these birds were always aloft in the winters, feeding in the air columns. The tags only recorded data every 4 minutes, so these birds could have landed intermittently. But these results indicate that the swifts go long periods without sleep in the conventional sense.
Sleep is incredibly diverse across the animal kingdom, with some animals sleeping two hours, and others sleeping 20. Many factors influence sleep in wild animals, including food, predation, and trophic level (position in a food chain). It is generally thought that every species has a specific sleep “quota,” or an average amount that they sleep every day. However, recent research has shown that there is some flexibility in sleep requirements for some species.
Just prior to migration, white-crowned sparrows reduce their sleep time by two-thirds, yet do not show any of the cognitive impairment generally associated with sleep deprivation. This migratory restlessness has been observed in other bird species, and can be induced in the lab by artificially shortening the length of day. During the very short Alaskan summer, pectoral sandpipers stay awake for almost 2 weeks to maximize breeding opportunities. The males that sleep the least sire the most offspring – a rare case where sleep deprivation is an evolutionary advantage.
One of the big topics of discussion in my undergraduate Astrobiology class at Appalachian State University (ASU) is the question of intelligent life beyond Earth, as it is, in my view, probably the single most intriguing question in astrobiology. Indeed, the prospect of life existing beyond Earth has fascinated humankind for centuries, with the first scientific thinking on the subject dating back to the Ancient Greeks. Advanced modern technology has led to formalized study on the Search for Extraterrestrial Intelligence (abbreviated, SETI), and the popularization of this topic over the last several decades has been spurred on from the pioneers of SETI, most notably the astronomers Frank Drake and Jill Tarter of the SETI Institute in Mountain View, CA, and the late astronomer Carl Sagan.
While we have no evidence whatsoever for life of any kind, even the most simplest microbes, beyond our planet, humans seem to be drawn to this search, and in so doing, ponder the possibilities of what could be out there, and what such a discovery would mean for life on Earth. A recent boost in proponents of SETI came just earlier this month with a report from a new data analysis from NASA’s Kepler spacecraft which revealed that there could be as many as 40 billion Earth-like planets in our Galaxy, alone. This means that one out of every five Sun-like stars in the Galaxy could house a potentially habitable planet!
(You can interact with some of Kepler’s discoveries with this cool animation tool).
So, then where is everybody? This apparent contradiction in seemingly high estimates for extraterrestrial intelligent life in the Galaxy and our lack of evidence for such life was famously questioned by the physicist Enrico Fermi in 1950, and is known as the Fermi Paradox, which has several proposed theoretical solutions. In spite of this paradox, many scientists remain hopeful that extraterrestrial intelligence is out there, with a reasonable chance of detecting it, with modern estimates for potential communicative civilizations achieved through the Drake Equation (sometimes called the Sagan-Drake Equation).
Recently, I gave my Astrobiology class an assignment to write whether they thought SETI — the ongoing search for intelligence beyond Earth — was a waste of time and/or money, knowing that, with the vast distances of space, any possible radio signal from an intelligent civilization could take thousands of years (which is likely a minimum) to reach us, if they were being sent at all?
This assignment was a contest, such that the most convincing response would be published on this astronomy blog site. Below are two chosen excerpts, and a third in its entirety. All students are sophomores in ASU’s Honors College, many are non-science majors, and all illustrate several of the prevailing viewpoints that span generations of scientists today.
Student Jack Schaufler cites the large gain in SETI against the small economic cost:
SETI will continue to expand, with new detectors suitable for optimal wavelengths predicted to increase the list of SETI targets to hundreds of thousands of stars. The potential implications of contacting intelligent life are huge. It would drastically change our lives here one Earth, causing an increase in scientific interest as well as a shock throughout the religious world. The risk involved with maintaining SETI is a mere 2.5 million dollars a year, equal to the price of 5 Tomahawk Cruise Missiles out of the 830 billion dollars the US spends on defense a year. Keeping SETI operational requires much less risk than the potential reward.
As a counter view, student Zachary Lachance thinks there is probably a very low likelihood for success with SETI:
Due to the idea that older intelligent life should have already existed in the universe and the lack of evidence to support the idea that this intelligent life has made contact with Earth, it is safe to assume that SETI will fail because intelligent life should have already colonized the galaxy…. Unless intelligent life is so rare that some form of it has yet to colonize the Galaxy or communicate, SETI will still most likely fail due to the small probability of intelligent life existing or the large distance between Earth and another intelligent civilization. Once you add in all of the planets that do not, as far as we can tell, contain intelligent life, finding intelligent life would still be similar to finding a needle in a large, seemingly never-ending haystack. Therefore, the prospects of SETI seem bleak and SETI is destined to fail.
The most convincing overall response was by student Jonathan Solomon. It is pro-SETI.
The Search for Extraterrestrial Intelligence (SETI) uses radio waves as a means of hopefully finding another civilization – one that is capable of receiving, deciphering, and transmitting radio signals of their own. The entire search relies upon several assumptions about other intelligent civilizations based on the history of the evolution of the human race’s technological capabilities and curiosities. One powerful assumption is that, evidenced by the age of the universe, Earth is in its infant stages regarding technology. If there is other intelligent life out there then it is reasonable that they are much older and more technologically advanced than humans are. Humanity has only had radio waves for about one hundred years, and the technological advances achieved during that period have been astounding. Roughly forty years after the advent of radio waves came nuclear technology. That is such an infinitesimally small time on the cosmic scale between harnessing to radio waves and having the capability of annihilating intelligent life as we know it. There are other assumptions about extraterrestrial intelligence that fuel debates between SETI proponents and opponents.
Many argue that if advanced alien civilizations exist, then they should have already made contact with Earth; if not the aliens themselves, then feasibly the aliens would have some form of self-replicating robots that would be capable of colonizing the universe. If, indeed, However, it is also possible that extraterrestrial civilizations could simply be thousands of light-years away and have simply not gotten close enough to us for humans to realize their presence. Another possible explanation is that interstellar travel is much more difficult than we currently assume. For instance, considering the high speeds that interstellar vehicles would have to travel, ensuring the safety of the vehicle would be extremely difficult (Shostak, 2002).
The importance of SETI, in my opinion, is that it brings hope. Knowing that somewhere out in the cosmos some intelligent civilization could have figured out how to coexist in such a way that it did not self-destruct would prove that humanity is not doomed. Ben Zuckerman, astrophysicist at UCLA, writes about how it is ironic that humanity is looking for extraterrestrial intelligence due to the overpopulation and overconsumption of our own planet (Zuckerman, 2002). I agree with him that humans need to change our consumption patterns if we wish to survive on this planet; however, I do not believe that the allocation of such a small amount of funds, when compared to the military budget, for example, is a waste. Rather, the spending of such a small amount of money on such a high reward is like a cosmic scratch card. If we do not end up winning, we did not expend many resources, and at least we tried; but if we end up hitting the jackpot, the implications are enormous.
[References: Shostak, Seth. SETIs Prospects Are Bright. Mercury. 2002. Print; Zuckerman, Ben. Why SETI Will Fail. Mercury. 2002. Print].
One of the most thought-provoking views on extraterrestrial civilizations comes, in my opinion, from Carl Sagan. This short video is excerpted from his original Cosmos broadcasts, and to me best summarizes the profound implications of finding life beyond Earth, within the context of a strong scientific platform:
If you believe life is out there and want to help in the search for ET signals, learn more about how you can participate in the SETI@home citizen science project that uses personal computers to search for and analyze radio signals.
While there’s bound to be some disaster in my kitchen this Thanksgiving, one thing I doubt will happen is that the food will float away. This Thursday, while we’re gobbling up various treats on the table, my mind will likely wander about 250 miles above the Earth to the International Space Station (ISS) and the astronauts there with their floating bags of various Thanksgiving goodies, wondering if perhaps some cranberries flew about beyond the table, or pieces of pumpkin pie perchance got stuck to the ceiling?
A few days ago, ISS Expedition Crew 38 beamed down a Thanksgiving message to us Earth-dwellers, giving us a taste of their holiday feast enjoyed in near-Earth orbit. While the cans look vaguely reminiscent of what I gave my cat for breakfast today, I can only surmise that it is probably the view that far surpasses the cuisine.
Happy Out-Of-This-World Thanksgiving!
By Meg Lowman
Teach your children well.
— Crosby, Stills, Nash & Young
The year 2013 marks the 100th birthday of the British Ecological Society (BES), so the International Congress of Ecology recently met in London to mark this auspicious occasion. Like many scientific professionals, ecologists reluctantly come away from their field sites or computer screens to exchange expertise on new tools, best practices and future priorities. But centennial conferences are once-in-a-lifetime events. What were the concerns of 3,000-plus global ecologists, as they spent a week discussing priorities for the next 100 years?
In her keynote address, BES president Georgina Mace, professor at University College of London, summarized the changing links between humans and their environments, explaining how past generations focused solely on preserving species and beautiful landscapes.
Only more recently are ecologists beginning to view conservation with an economic lens, defining the dollar values of fresh water, minerals, plant-based medicines and carbon storage as part of conservation planning. These products are called ecosystem services, whereby healthy natural landscapes provide benefits to humans. She explained that we need to acknowledge that conservation is directly tied to humans, and environmental solutions need to be human-driven. She also noted the importance of engaging multiple scientific disciplines to solve complex environmental issues.
In addition to the pervading consensus that ecology needs human drivers to promote sound decision-making, three other major priorities took center stage at the conference.
One was the announcement of a new manifesto for forest conservation. Acknowledging that past efforts to conserve tropical forests have not succeeded, 50 global forest ecologists co-authored a white paper declaring a new forest management paradigm — that leadership should be placed in the hands of local communities to minimize continued degradation of global forests. The manifesto also prioritized placing new technologies into the hands of local leaders for effective solutions.
Another priority for the next 100 years of ecology is citizen science, whereby non-scientists collect information for larger-scale environmental monitoring. Ranging from moth sighting to star-gazing, citizen science has been popular with amateurs for centuries in Britain. Emerging mobile technologies have made citizen science one of the fastest-growing, most innovative aspects of ecology, and ecologists are capitalizing on its popularity.
Perhaps most important for ecology’s future, a third priority was recognizing the next generation of scientists. A newly launched group called the International Network of Next-Generation Ecologists (INNGE) provided inspiration, energy and enthusiasm for the future of the discipline. As one of a handful of North Carolinians at this meeting, I believe the future is in good hands.
UPDATE: The solar eclipse of November 3, 2013, has ended. If you caught it (we saw the last few minutes with a makeshift pin-hole camera), or if you missed it altogether, you can see some stunning images here, many of which are from North Carolina.
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There are two reasons to celebrate tomorrow’s dawn (Sunday, November 3, 2013) in the Eastern US. First, we get an extra hour of sleep due to Daylight Savings (which pleases this writer immensely); second (and perhaps more interestingly), a rare solar eclipse will be visible at sunrise (~ 6:39 AM EST), lasting for about 30 to 45 minutes, given clear skies. Viewing will be low in the sky, roughly 8 degrees from the East-Southeast horizon. (SEE THE WARNING AT THE END OF THIS POST ABOUT VIEWING THE SUN SAFELY).
North Carolinians are in luck: with weather forecasts predicted to be clear at dawn, the Southeastern US should have the best viewing in this part of the world.
A solar eclipse occurs when the Moon passes between the Earth and the Sun such that the Moon’s shadow blocks some portion of the solar disk along our line of sight from Earth. Usually solar eclipses are either partial (meaning only a portion of the Sun will be obscured) or total, from all parts of the world at the same moment in time.
Tomorrow’s event is highly unusual in that it will be a hybrid solar eclipse; that is, it will be partial in some parts of the world (the Eastern US and Canada), while total in others (Africa). The partial portion will be for the first several seconds, followed by the total eclipse in Africa for the remaining passage. Maximum eclipse will reach Uganda at 5:23 PM local time.
To watch the total eclipse from Africa, the Slooh Community Observatory in the Canary Islands will be hosting a live feed.
This will be the last solar eclipse of 2013.
This will be your final chance to witness a hybrid eclipse, too. Of the nearly 12,000 solar eclipses listed between 1999 BCE and 3000 ACE, only 4.8% are hybrids. The last one was on November 20, 1854, and the next won’t be until October 17, 2172.
The unusual path of this eclipse occurs due to the Moon’s umbra – the innermost and darkest part of its shadow — piercing the Earth at some locations while missing it entirely in others. The path’s geometry is due to the curvature of the Earth’s surface bringing some geographical locations into total shadow, while others in the path of partial shadow.
What does a solar eclipse look like from space? See below for gorgeous footage of the August 6, 2013 solar eclipse, taken by the Solar Dynamics Observatory, which images the Sun from an altitude above Earth of about 36,000 km.
This compilation is from helioviewer, a NASA/ESA solar viewing website.
WARNING! VIEWING THE SUN DIRECTLY, EVEN DURING AN ECLIPSE, CAN CAUSE SERIOUS EYE DAMAGE. CLICK HERE FOR SAFE VIEWING TIPS.
BOO! The origins of Halloween can be traced back to medieval European astronomical calendars.
Surprised? Indeed, there’s not much astronomy in sticky-fingered pint-sized ghosts knocking on your door begging for candy. But the historical roots between Halloween — or, Hallowe’en, a contraction of All Hallow’s Evening (or, All Hallow’s Eve) — and astronomy trace back to medieval astronomical divisions of a year, and to festivals with Gaelic, Pagan, and Christian influences. In fact, the assimilation into North American culture of Halloween as we know it today, with a wide range of both frightening and humorous costumes, as well as trick-or-treating, did not happen until the late 19th to early 20th centuries.
The astronomical roots of the Gaelic, or Celtic harvest festival, Samhain — known as the “Lord of Darkness” in Ireland, from which Halloween derives, are found in its placement in the medieval calendar year as one of four cross-quarter days, where it remains today. As the name implies, cross-quarter days fall between the four quarter days — days separated by roughly three months and near the two solstices (highest or lowest point of the Sun in the sky, in June and December) and two equinoxes (the point at which the Earth’s equatorial plane passes the center of the Sun such that the Earth is neither tilted toward nor away from the Sun, in March and September). Quarter days were originally religious festivals, and, while now limited in significance, leasehold payments and rents for land and premises in England are often still due on the old English quarter days.
Aside from Halloween, the other cross-quarter days are now known as Groundhog Day (February 2), May Day (May 1), and Lammas (August 1), and unless you get spooked by the slumbering Groundhog in early February, Halloween is probably the scariest of the cross-quarter days. The original Samhain traditionally marked the beginning of winter, and, in Western Christian cultures, included a feast for remembering the dead. All Hallow’s Eve was when saints (or, hallows), martyrs and faithful departed believers were thought to wander among the living. These departed souls were also believed to join the living during this one night to celebrate with their family, tribe or clan, then return to the land of the dead the following day (often referred to as All Saint’s, or All Hallow’s, Day).
Samhain marked the end of the harvest season and the beginning of winter. Traditionally the time to take stock of food and herb supplies, and was marked by various rituals, including bonfires and divination games, it also was the boundary between light and dark, the dead and the living. The lighting of a jack-o-lantern in fact originates back to the tradition of frightening evil spirits on All Hallow’s Eve.
History aside, there are other, perhaps more tangible, and certainly aesthetically beautiful connections between astronomy and Halloween. One particularly glorious example is the Witch Head Nebula, named for its resemblance to a fairy tale witch’s head (rightward facing, chin at bottom):
Another aptly spooky supernova remnant is the Veil Nebula. Near the constellation Cygnus, the portion of the Eastern Veil shown gloriously below, spans only about 1/2 degree in the sky, about the size of the Moon.
While perhaps “veil-like”, I see more of a bat with wings extended:
In the western part of the Veil lies another seasonal apparition, the Witch’s Broom, another portion of the same remnant, this time resembling, you guessed it, a witch’s broom, with the sweeping end of the broom facing bottom right of the image:
Finally, the “Ghost Head” Nebula, or NGC 2080, is a star-forming region staring menacingly from the Large Magellanic Cloud, a satellite galaxy of the Milky Way. The glowing eyes of the “ghost” are called A1, the western patch, called A1, which has a bubble in the center that was created by the young, massive star it contains. The eastern patch, called A2, is composed of a cluster of several young stars.
So how astronomically spooky will tomorrow night be? Well, the star Algol, fittingly known as the “Demon Star”, will be up for a few hours centered on 10:35 PM Eastern Time, in the constellation Perseus.
Algol is in fact a triple star system, with designated component stars, A and B. The animation below shows a ghost-like Algol B orbiting the brighter Algol A.
But worry not, the superstitious among you. Werewolves will be kept at bay while you trick-or-treat or otherwise celebrate this year’s All Hallow’s Eve — October 31, 2013 will be virtually Moonless.
So, if you celebrate Halloween in all its ghoulish glory, if it’s an afterthought, or even if you give it no thought at all, have a safe, happy, astronomically fun day tomorrow!
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Sly does it. Tiptoe catspaws. Slide and creep.
But why? What for? How? Who? When! Where did it all begin?
‘You don’t know, do you?’ asks Carapace Clavicle Moundshroud climbing out
under the pile of leaves under the Halloween Tree. ‘You don’t really know!”
—Ray Bradbury, The Halloween Tree
Greetings Blogophiles! Happy Fossil Friday!… What?… is this another thing to be aware of? Didn’t we just do cephalopod days and Earth science week? My brain is full, I want to go home. Sorry folks, science never sleeps. Turns out, every Friday is #FossilFriday on Twitter. What?…Why? … How can I be involved? Every Friday on Twitter, paleontologists and interested amateurs around the world tweet images of some of their favorite fossils and/or links to their blogs or scientific papers. This is a pretty cool, very quick way to expose people to some of the fossils which are stored in museum collections or are on exhibit, and to the research paleontologists are doing. Anyone with a Twitter account can do it. This Friday alone I have seen pictures of Parasaurolophus skeletons, a spiny trilobite, a knobby headed mammal (classified as a dinoceratan), some belemnites, and a Neanderthal Skull. If you’d like to participate by tweeting a picture of your favorite fossil or to just look at some spectacular fossils, go to twitter.com and in the search field type #FossilFriday. Perhaps you’ll see something you’ve never seen before.