Archive for the ‘SECCHI’ tag

The Secchi Dip-In

By July 20th, 2013 at 11:57 am | Comment 1

Water Testing

Calling all water monitoring groups! It is time for the annual Secchi Dip-In. From now until July 22, volunteer and professional water monitoring groups are being asked to take transparency measurements in a local body of water.

Secchi DiskA secchi disk is a common tool for measuring water turbidity, or water cloudiness. Turbidity is caused by small particles suspended in the water and is a reflection of water quality. To take turbidity measurements, on a calm and bright day the user lowers the disk into the water until the disk is no longer visible. The depth of the disk is used to calculate turbidity. Land erosion from construction or mining, pollution run-off or increases in algae all lead to higher turbidity.

Started in 1994 at Kent State University, Ohio, the Dip-In always takes place during the first few weeks of July. Participants only have to take one transparency per body of water with their secchi disk. The project helpfully provides links for purchasing disks if you do not already have one.

While project organizers prefer that measurements are taken during the “official” dip-in period, participants are welcome to add data from anytime of the year as well as past years. Currently over 2,000 water bodies are being tracked, most of which are in North America. The data are accessible to anybody interested.

In addition to transparency measurements, participants are asked to give their general impressions of the water quality as well as the area’s general aesthetics and recreational properties. These qualitative data help project researchers ascertain the potential sources affecting water quality.

To learning more or to participate, visit  Secchi Dip-In.


Find other environmental projects (and over 600+ other citizen science projects) using our Project Finder.


Dr. Carolyn Graybeal earned her PhD in neuroscience from Brown University in partnership with the National Institutes of Health. After graduating, she became a Christian Mirzayan Science & Technology Policy Fellow with the National Academies of Science where she had the opportunity to immerse herself in the policy side of science. In addition the human brain, she is interested in the influence of education and mass media in society’s understanding of science. Originally from California, she is learning to identify the four seasons of the East Coast and is getting pretty good at it.

Comet Lovejoy grazes the sun!

By December 22nd, 2011 at 3:38 pm | Comment

In this video from the U.S Naval Research Laboratory (NRL), Comet Lovejoy takes a death-defying journey through several-million degree solar corona as it passes the Sun on December 15th, 2011 (EST). The comet defied the expectations of many experts by not only surviving its solar plunge but re-emerging as strong and bright as before.

“It’s absolutely astounding,” says Karl Battams, computational scientist at NRL. “I did not think the comet’s icy core was big enough to survive plunging through the several million degree solar corona for close to an hour, but Comet Lovejoy is still with us.”

Comet Lovejoy zooms toward the sun. This is the SECCHI COR-1 (inner coronagraph) image on the STEREO-B satellite. (Image: STEREO/SECCHI image courtesy NASA/NRL)

Comet Lovejoy zooms toward the sun. This is the SECCHI COR-1 (inner coronagraph) image on the STEREO-B satellite. (Image: STEREO/SECCHI image courtesy NASA/NRL)

The imagery used for this video was gathered from NRL’s Sun-Earth Connection Coronal and Heliospheric Investigation (SECCHI)/EUVI-A instruments, which are a part of the NASA Solar Terrestrial RElations Observatory (STEREO) mission. STEREO consists of two space-based observatories – one ahead of Earth in its orbit, the other trailing behind. With this new pair of viewpoints, scientists are able to see the structure and evolution of solar storms as they blast from the Sun and move out through space.

Why am I telling you all of this? Well, Comet Lovejoy was discovered on Dec. 2,  2011, by a citizen scientist — Terry Lovejoy of Australia. As it turns out, it’s not all that uncommon for comets to be discovered by citizen scientists from the public. For years, NRL’s Sungrazing Comets Project has asked people to help discover new comets.

Read the rest of this entry »