From The Director

by Rex Parker, PhD

May 9 Meeting – Election of Officers.  Through our 60-year history we have elected officers (the Board of Trustees) for new 1-year terms at the May meeting as provided in the by-laws.  Nominations committee chair Lee Sandberg has reported that each of the current officers is willing to serve again, forming a slate for the election.  The 7 candidates for the Board positions are Rex Parker (Director), Larry Kane (Assistant Director), Michael Mitrano (Treasurer), Gene Allen (secretary), Victor Davis (Program Chair), Dave Skitt (Observatory Chair), and Bill Murray (Outreach Chair).  For your information, the constitution, by-laws, and position descriptions are on the website

After the Break.  The tradition each month is for a member to give an Unjournal Club, a ~10 minute excursion into astro thoughts and activities, to begin the second half of the meeting.  I call upon you to consider doing an Unjournal Club presentation to help the club as well as yourself get a little more involved in the flow of astronomy in AAAP.  You can use PowerPoint slides, JPEG’s, astro-images, travel pictures, book reviews — your imagination is the limit (note:  no need to bring a laptop computer, simply bring a USB memory stick).  To get onto the schedule for an upcoming meeting, please contact me or the program chair.

Insects Share a Big Problem with Astronomers.  Excess night lighting is as damaging to small flying creatures as it is for astronomers.  As the stars fade from view we are blinded from seeing ourselves in relation to the cosmos, losing our perspective — just as moths are trapped in the glare of lamps.  Entomologists are reporting that the decline of insect populations around the world is related to excess outdoor lighting at night.  Why are insects drawn to light to their demise?  This question becomes highly relevant amid recent increases in light pollution and the decline of insect populations, which threatens to crash entire ecosystems for which insects are an essential major component.

The underlying biological mechanism for nocturnal insects’ attraction and rapid flying around flames and lamps, often to their demise, has been difficult to determine.  The 3-D tracking of small moving objects in low light is technically difficult (a challenge well-shared by astro-imagers), and necessary tools did not exist before.  Previous theories include lunar navigation, escaping towards light as if it were a “gap” in the foliage, and blinding of sensitive eyes.  All flying animals need a reliable way to determine orientation to the external world, especially with reference to the direction of gravity.  Throughout insects long evolutionary history, the sky has been the brightest part of the visual field, making it a robust indicator of “up”. This is true also at night, especially at short wavelengths. 

A new report (posted April 12, 2023) on BioRxiv, the preprint server for biology, provides novel insight to how this happens (Fabian et al., Why flying insects gather at artificial light | bioRxiv).  This paper caught my eye upon return from a nature tour of Costa Rica – the authors’ field studies were conducted at Monteverde in Costa Rica.  Fabian and colleagues used high-speed (500 fps) and high-resolution imaging in the field and lab to study the kinematics of insect flights around artificial light. They show that artificial point light source induces abnormal flight behavior in insects.  But contrary to expectations of attraction, insects do not steer directly toward the light. Rather, they turn their backsides toward the light and fly perpendicular to the light source. They consistently fly orthogonal to the light source. Under natural sky light this dorsal tilting maintains proper flight attitude and control. But near artificial lamps, the dorsal light response causes steering around the light and traps the insect in endless loops.  

The authors conclude that the dorsal tilting causes the erratic flight paths of insects near lights, providing the most plausible model for why flying insects gather and become entrapped at artificial lights.  They suggest that light entrapment of insects at a local scale is due to a corruption of the insect’s attitude control rather than navigation.  Bright nearby lights disrupt this mechanism and cause unintentional course alterations in insect flight.  Reducing bright, unshielded, and upward facing lights will mitigate the impact on flying insects, simultaneously helping restore the sky to our own eyes and telescopes.

This entry was posted in May 2023, Sidereal Times and tagged , . Bookmark the permalink.

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