Shark monitoring with new space agency tags

From WPTV TV in Florida, USA:

The importance of great white sharks; scientific community is testing & tagging sharks off Florida

Jan 30, 2018

There is important research underway right now off the Florida coast.

Researchers fear the great white shark population may be declining, and if that’s the case, lots of other fish species will decrease. That would have a great impact on all of us.

Mary Lee, Hilton, George and Savannah are just some of the eastern seaboard great white sharks that have been on the Ocearch floating lab, and researchers say they need more.

Savannah pinged off our coast a few times in January, including near Port St. Lucie on Jan. 9. Her last known location was near Key West.

“Ship of opportunity for researchers like myself,” Dr. Bob Hueter, a senior scientist at the Mote Marine Lab in Sarasota and chief science advisor for Ocearch.

This is day eight of 25. Ocearch is in the middle of its 31st shark expedition, and Hueter’s 10th. …

Fischer says this is the only ship in the world that can board a great white, test it, tag it and release it without dying.

“The lift really is what makes the impossible possible,” Fischer said.

The scientists on board take samples of the shark. If she’s pregnant, an ultrasound.

They’ll attach a tracker to the dorsal fin. When it surfaces, it’s pinged by a satellite.

Savannah last buzzed our coastline earlier this month.

“She showing us where the nursery of tweener type shark is living and how big that is and we know how to manage it”, Fischer said,

Whites are born at about 4.5 feet and aren’t mature until they’re about 15 feet. Savannah is about 8 feet.

“As you see more and more white sharks in Florida and more and more other species of sharks, you’re going to see more and more fish,” Fischer said.

On this day — we didn’t catch any sharks. They only need one in their 25 days to make their expedition worth it.

The next shark they catch will feature a new transmitter, created by the European Space Agency. It’s never been used on an animal before, but Ocearch says it will provide more data and the battery lasts longer.

The next expedition is set for May, called the Gulf Stream drift starting off the coast of Miami and headed north.

Today, Dutch Vroege Vogels radio told 4 February 2018 is the last day of the expedition, and so far they had not caught sharks; as the sea water this winter is colder than usually, so the sharks are absent from where they are usually. The new tags invented by ESA would be able to provide much more information than the older tags, about depths at which sharks swim etc.

Saturn’s strange radio waves

This video is called 5.6k Saturn Cassini Photographic Animation.

From the Daily Galaxy:

May 12, 2012

Weekend Feature: “Saturn‘s Strange Voice” — Radio Waves Vary at Its North and South Hemispheres

Data from NASA’s Cassini spacecraft show that the variation in radio waves controlled by the planet’s rotation is different in the northern and southern hemispheres. Moreover, the northern and southern rotational variations also appear to change with the Saturnian seasons, and the hemispheres have actually swapped rates.

Click to hear Saturn‘s Eerie Voice.

“The rain of electrons into the atmosphere that produces the auroras also produces the radio emissions and affects the magnetic field, so scientists think that all these variations we see are related to the sun’s changing influence on the planet,” said Stanley Cowley, co-investigator on Cassini‘s magnetometer instrument.

“These data just go to show how weird Saturn is,” said Don Gurnett, Cassini’s radio and plasma wave science instrument team leader, and professor of physics at the University of Iowa, Iowa City. “We thought we understood these radio wave patterns at gas giants, since Jupiter was so straightforward. Without Cassini’s long stay, scientists wouldn’t have understood that the radio emissions from Saturn are so different.”

Saturn emits radio waves known as Saturn Kilometric Radiation, or SKR for short that sound like bursts of a spinning air raid siren, since the radio waves vary with each rotation of the planet. This kind of radio wave pattern had been previously used at Jupiter to measure the planet’s rotation rate, but at Saturn, as is the case with teenagers, the situation turned out to be much more complicated.

When NASA’s Voyager spacecraft visited Saturn in the early 1980s, the radiation emissions indicated the length of Saturn’s day was about 10.66 hours. But as its clocking continued by a flyby of the joint ESA-NASA Ulysses spacecraft and Cassini, the radio burst varied by seconds to minutes. A paper in Geophysical Research Letters in 2009 analyzing Cassini data showed that the Saturn Kilometric Radiation was not even a solo, but a duet, with two singers out of sync. Radio waves emanating from near the north pole had a period of around 10.6 hours; radio waves near the south pole had a period of around 10.8 hours.

A new paper led by Gurnett shows that, in Cassini data, the southern and northern SKR periods crossed over around March 2010, about seven months after equinox, when the sun shines directly over a planet’s equator.

The southern SKR period decreased from about 10.8 hours on Jan. 1, 2008 and crossed with the northern SKR period around March 1, 2010, at around 10.67 hours. The northern period increased from about 10.58 hours to that convergence point.

Seeing this kind of crossover led the Cassini scientists to go back into data from previous Saturnian visits. With a new eye, they saw that NASA’s Voyager data taken in 1980, about a year after Saturn’s 1979 equinox, showed different warbles from Saturn’s northern and southern poles. They also saw a similar kind of effect in the Ulysses radio data between 1993 and 2000. The northern and southern periods detected by Ulysses converged and crossed over around August 1996, about nine months after the previous Saturnian equinox.

Cassini scientists don’t think the differences in the radio wave periods had to do with hemispheres actually rotating at different rates, but more likely came from variations in high-altitude winds in the northern and southern hemispheres.

Two other papers involving Cassini investigators were published in December, with results complementary to the radio and plasma wave science instrument – one by Jon Nichols, University of Leicester, and the other led by David Andrews, also of University of Leicester.

In the Nichols paper, data from the NASA/ESA Hubble Space Telescope showed the northern and southern auroras on Saturn wobbled back and forth in latitude in a pattern matching the radio wave variations, from January to March 2009, just before equinox. The radio signal and aurora data are complementary because they are both related to the behavior of the magnetic bubble around Saturn, known as the magnetosphere.

The paper by Andrews, a Cassini magnetometer team associate, showed that from mid-2004 to mid-2009, Saturn’s magnetic field over the two poles wobbled at the same separate periods as the radio waves and the aurora.

As the sun continues to climb towards the north pole of Saturn, Gurnett’s group has continued to see the crossover trend in radio signals through Jan.1, 2011. The period of the southern radio signals continued to decrease to about 10.54 hours, while the period of the northern radio signals increased to 10.71 hours.

“These papers are important in helping to explain the complicated dance between the sun and Saturn’s magnetic bubble, something normally invisible to the human eye and imperceptible to the human ear,” said Marcia Burton, a Cassini fields and particles scientist at NASA’s Jet Propulsion Laboratory.

‘Magic island’ appears out of nowhere on Titan, Saturn’s biggest moon, then quickly disappears: here.

The European Space Agency (ESA) has announced a €1.1 billion unmanned mission to the ice moons of the planet Jupiter. A robotic spacecraft, named the JUpiter ICy moons Explorer (JUICE), is set to launch in 2022 and arrive at Jupiter in 2030. It will study Europa, Callisto and Ganymede, three of the four “Galilean satellites,” named after the Galileo Galilei, who first observed them in 1610: here.

Jupiter moon spouts “curtains of fire” in crazed series of eruptions: here.

Voyager spacecraft approaching interstellar space—35 years after launch: here.

NGC 4178 enjoyed the single life. Even though the flat, disc-shaped galaxy was getting on a bit, it had a svelte spiral figure to be proud of. Its central black hole was perfect: not too small, not too large. It had never been involved in a major merger with another galaxy, and wanted to keep it that way. None of the unsightly bulges and warps associated with too much socialising for NGC 4178: here.

Voyager 1 is going, going, but not quite gone from the Solar System: here.

In a historic scientific and technical accomplishment, NASA astronomers operating the Voyager 1 spacecraft confirmed on September 12 [2013] that after 36 years and 19 billion kilometers, humanity’s most distant object has entered interstellar space. Moreover, the findings of Voyager 1’s research team show that the probe left the solar system more than a year before: here.