Mercury is a poisonous metallic element that is liquid at room temperature.

There's nothing like producing a controversial story on some favorite food group to have a profound effect on one's appetite. I gave up chicken after doing a story on factory farms (I already didn't eat beef or pork or I would have eliminated those as well.) Now, fish, too, has fallen from grace. Ignorance was bliss.

I've known for quite some time that some fish, especially tuna, were high in mercury. But discovering the extent of the problem, and that halibut and sea bass were also on the “do not eat too much of” list, was eye-opening for me. Now I count fish servings like some people count calories. Japanese cuisine, one of my favorites, has lost some of its glow, as well as its frequency in my dining-out plans.

Many of you have practical questions, as did I. How big a crimp does this have to put in my diet? How much is too much? How often is too often? Can I still enjoy that tuna sashimi and not worry about mercury overload?

Because there wasn't time in the QUEST TV segment on mercury in the bay to include information on safe fish eating practices, below are the guidelines, along with web links, to help you get plenty of Omega 3s and still keep your mercury levels low.

Here's what California's Office of Environmental Health Hazard Assessment says about eating fish from the San Francisco Bay and Delta Region.

• Women beyond childbearing age and men should eat no more than two meals per month of San Francisco Bay sport fish, including sturgeon and striped bass caught in the delta. (One meal for an adult is about eight ounces).
• Women beyond childbearing age and men should not eat any striped bass over 35 inches.
• Women of childbearing age, pregnant, nursing mothers, and children should not eat more than one meal of Bay fish per month. In addition, they should not eat any striped bass over 27 inches or any shark.
• This advisory does not apply to salmon, anchovies, herring, and smelt caught in the bay; other sport fish caught in the delta or ocean; or commercial fish.
• Richmond Harbor Channel area: In addition to the above advice, no one should eat any croakers, surfperches, bullheads, gobies or shellfish taken within the Richmond Harbor Channel area because of high levels of chemicals detected there.

Here’s a summary of the joint fish advisory published by the FDA and EPA for women who are pregnant, breastfeeding or may become pregnant and for children. This is a general advisory not exclusive to any water body.

• Do not eat Shark, Swordfish, King Mackerel, or Tilefish because they contain high levels of mercury.
• Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in mercury. Five of the most commonly eaten fish that are low in mercury are shrimp, canned light tuna, salmon, pollock, and catfish.
• Another commonly eaten fish, albacore ("white") tuna has more mercury than canned light tuna. So, when choosing your two meals of fish and shellfish, eat only up to 6 ounces (one average meal) of albacore tuna per week.
• Check local advisories about the safety of fish caught by family and friends in your local lakes, rivers, and coastal areas. If no advice is available, eat up to 6 ounces (one average meal) per week of fish you catch from local waters, but don't consume any other fish during that week.
• Follow these same recommendations when feeding fish and shellfish to your young child, but serve smaller portions.

Also, check for local advisories for each water body in California that has fish consumption guidelines. They vary by water body.

And lastly, here’s some practical advice from Dr. Jane Hightower, the medical doctor who we feature in the mercury story.

• “If you’re genetically susceptible, it’s really important to know that if you are an autoimmune-prone patient, Lupus, MS, thyroiditis, these kinds of things, then you should not consume mercury on a regular basis or at all. … And then the cardiac patients. You know, mercury can cause a reaction in vessels that leads to inflammation. So you want to have your Omega 3 fatty acids, which is anti-inflammatory. And not have mercury which is pro-inflammatory…. If you want to avoid significant mercury and you just don’t know what the mercury content is in the fish, a rule of thumb is to eat the small fish. Not a piece of the fish. If it comes in a steak, you want to know how big the fish was that the steak came from. You want the whole fish to fit on your plate. Don’t buy a bigger plate. Get a smaller fish. With the exception of salmon. Salmon can have elevated mercury, but very rarely.”

Good luck, good health, and and watch out for bones!




Watch the Mercury in San Francisco Bay television story online.

Which is worse for you, a can of tuna or a broken CFL bulb? Sorry, Charlie… image by Dave LifsonA paper expected to be published in the August issue of the lighting industry journal, LD+A, may quiet some of the controversy over the dangers of mercury in compact fluorescent lights (CFL). I’ve argued in this blog that the cut in mercury emissions from power plants due to the electricity saved when traditional incandescent bulbs are replaced with CFLs, greatly outweighs the amount of mercury that could escape from broken CFLs, plus what is emitted during the making and transportation of CFLs. But the paper, by Robert Clear, Francis Rubinstein, and Jack Howells, who do research at Lawrence Berkeley National Laboratory (LBNL), goes a step farther by showing that even a person who breaks a lamp is more at risk from mercury in the environment than from the mercury in the lamp itself.

The researchers point out that there is a distinction between the kind of mercury that you are exposed to from broken CFLs—elemental mercury—and the mercury emitted from power plant smokestacks after it finds it’s way into waterways and oceans, where it becomes methyl mercury. Methyl mercury accumulates all up the food chain, so that large fish like tuna can contain a lot of it. Methyl mercury crosses the blood-brain barrier and passes through a pregnant woman’s placenta to her fetus. Methyl mercury is responsible for developmental problems, while elemental mercury, which is inhaled, appears to be more of a hazard for adults and children, and only then in the case of severe or prolonged exposures. In most mild cases, when the elemental mercury exposure ends, the bad effects diminish and go away. This is unfortunately not true for the developmental problems caused by methyl mercury.

The startling conclusion of the paper is that in a worse case scenario—you break a CFL in a closed, unventilated room; you vacuum the carpet, throwing mercury into the air; you set the vacuum in a corner; and then sit in the room breathing for eight hours—the amount of mercury exposure is about equivalent to the exposure you’d get from eating a can of Albacore tuna.

Eating a can of tuna has positive health effects as well as the negative health effects from the mercury. There are no positive health effects from a broken CFL, and you can reduce your exposure. The researchers suggest that in the case of a broken CFL, you should immediately open a nearby window. You can limit contamination by gathering up the large pieces of the broken bulb into a bag and set the bag outside. The room should then be left to air out for an hour or so. If the lamp broke on a carpet you can vacuum, but it should be done quickly while the room is being ventilated, the vacuum cleaner should be removed to an outside area, and again the room should be left vacated for an hour or so. Once the vacuum cleaner has cooled, you can empty the contents of the vacuum cleaner bag into the bag with the broken bulb. Take the bag to your nearest recycling center.

MESSENGER's color filter imaging capability reveals variations
in color on Mercury too subtle for the human eye.
Photo credit: NASA/MESSENGERLike a snow-bird relative vacationing in warmer climate localities and sending back picture postcards of their trip, NASA's MESSENGER spacecraft has made yet another swing past our Solar System's innermost planet, Mercury. But, like the traveler who just can't seem to get enough sightseeing in, this was another whirlwind flyby set to the furious tempo of a camera snapping pics–about 1200 in all…

Did MESSENGER find anything new, since its first flyby back in January? Here are a few highlights:

• Prominent "ejecta" rays streaking out from several large craters–previously revealed only by radar imaging from Earth, now photographed for the first time.

• 30% more of Mercury's largely unexplored surface than had been revealed by the Mariner 10 flybys in the 70's and MESSEGNER's own first flyby last January (spacecraft–namely Mariner 10 and MESSENGER–have now imaged 95% of Mercury's surface).

• "Hyper-color" (my own word) imaging of surface features that reveal variations in color too subtle for the human eye to notice, providing information on soil and rock composition.

I'm a planet junkie–and Mercury has always had a special place in my imagination. One might think of Mercury as the least interesting planet, in our Solar System as well as among dozens of "exoplanet" systems yet discovered. After all, it's a small, dry, cratered, and airless lump of rock and dust, resembling for the most part Earth's Moon. Consider, however, the point of view of someone who's favorite place on Earth is dry, dusty Death Valley, and my enamorment might not come as such a surprise.

In my imagination I see towering cliffs, enormous, deep crevasses, wide, flat dusty plains, bright brights in sunlit patches and dark darks in shadow….

But it's really its differences from Earth that make Mercury such an appealing exotic vision. Being where it is, 36 million miles from the Sun (about a third the Earth-Sun distance), the sunlight striking the Mercurian landscape is six times brighter–imagine that! And not just the visible light spectrum, but all the wavelengths of light the Sun puts out are free to impact Mercury's surface, unimpeded by an atmosphere: infrared, ultraviolet, X-rays, and potent burst of gamma rays rain down intensely on the planet's plains, mountains, and craters.

Speaking of the Sun, its behavior in Mercury's skies is, to say the least, zany. Mercury orbits the Sun in about 88 days (Earth days), but rotates so slowly that a single Mercurian day (the time from one high noon to the next) is about 115 Earth days. Not only does that mean sun-up to sun-down lasts roughly a couple of months, but that Mercury's orbital motion has a greater effect than its rotation on the Sun's apparent motion through its sky. The complicated relationship between Mercury's year and its day also causes the Sun to go "retrograde" at times–that is, periodically halt its progress from one horizon to the other and temporarily go in the opposite direction.

So, our prodigal vacationer MESSENGER has its itinerary straight: a climate with the brightest, warmest sunlight, pristine landscapes, long sunny days, and big skies that perform tricks for its amusement. Now, if only there was a beach…

I've been a cheerleader for compact fluorescent lamps (CFL) in this blog and will abandon the technology in a millisecond. When it comes to technology, my loyalties are short lived. I'm writing this from Asilomar State Park in Pacific Grove, California, during the American Council for an Energy Efficient Economy (ACEEE) bi-annual Summer Study on energy use in buildings. Early in the week, the plenary speaker and a 2008 ACEEE Champion of Energy Efficiency, Philips Lighting's Kevin Dowling, Vice President for Innovation in Solid State Lighting, turned my head from CFLs to light emitting diodes (LEDs), my new little darling, hero, and true lighting love.

Philips Lighting was the first manufacturer to commercialize CFL bulbs in the 1970s, and has long been an innovator, as well as being the largest manufacturer of lighting products in the world. "We aren't even near the limits to this technology," said Dowling. Technically, solid-state lighting, or LED lighting, is ready to be the next big thing after CFLs. The challenge that remains is making LED lighting affordable and ubiquitous. That is a challenge when you consider that today's incandescents work in 1880s-style fixtures. Dowling proved it in a backroom of the Smithsonian in Washington D.C. And in the progressive Pacific Northwest, after 15 years on the market, CFLs have achieved only 8% market penetration.

But LEDs are an easy sell. Compared to incandescent lights, which produce 10–12 lumens per watt (lpw), and fluorescents, which produce 90-100 lpw, the best LEDs produce approximately 100 lpw, have the potential to reach the 150–200 lpw level, can last 35 years and don't release any mercury into the environment. History has shown that the cost of LED technology has decreased, while performance has increased– both exponentially. Dowling expects LED lighting performance to continue increasing 35% per year while the price decreases about 20% per year, and that in 24-36 months LED lighting will reach the level of linear fluorescent lights in light output per watt of energy use.

LEDs have evolved from mostly lighting that attracts attention to lighting that illuminates. LEDs can produce a range of color temperatures, from cool to warm. It has been installed in the Old North Church in Boston to rave reviews from the curators of the historic church. Legislation is supporting the evolution of the lighting technology. Legislation and guidelines will raise lighting efficacy to at least 45 lpw by 2020, according to Dowling, making LEDs an easy choice.

Goodbye CFLs, it was good while it lasted.

A limb shot of Mercury's horizon taken by the
MESSENGER spacecraft on January 14, 2008.
Photo Credit "NASA/MESSENGER"

If you can take a name like "Mercury Surface, Space Environment, Geochemistry and Ranging" and craft it into a neat acronym like MESSENGER, then you may have a future working with NASA….

And no, this blog isn't about NASA acronymizations, but rather the heat-resistant robot behind one of them. MESSENGER is the space probe that NASA sent to Mercury to give the Solar System's innermost planet the first up-close look since 1975, when Mariner 10 flew by.

Though MESSENGER's main mission will begin in earnest when it returns to Mercury and finally settles into an orbit around the planet, on March 18th 2011, we were given a tantalizing peak last January 14th when the probe made its initial flyby.

What did this quick, on the fly snapshot tell us that we didn't know before? Well-a lot, considering Mercury has been one of the least understood planets in the Solar System, and was for a long time thought to be similar in character to our own Moon. Mercury is shaping up to be a lot less like Earth's Moon than its gray, cratered, airless appearance would mislead.

One key difference: density-how much material is packed into the planet; or how heavy a standard sized chunk of it would be. Our Moon is a lightweight on this score, with an average density of only 3.4 grams per cubic centimeter, while Mercury weighs in at a hefty 5.427 g/cc-almost as dense as Earth.

Another key difference: magnetic field. Planets like Earth and the Gas Giant worlds (Jupiter et al) generate respectable magnetic force fields, useful for everything from deflecting plasma flowing from the Sun (the "solar wind") to properly directing magnetic compass needles. Venus, Mars, and our Moon do not possess magnetic fields worth mentioning, as it turns out.

Mercury, on the other hand, does. Planetary magnetic fields are believed to be generated by currents in a planet's liquid outer core-like how the electric current in the wire coil of an electromagnet generates a magnetic field. Mercury's magnetic field suggests it still has some activity in its core-molten metals circulating in currents as the core slowly cools off. And speaking of Mercury's core, it appears to comprise 60% of the planet's mass-about twice what is "typical" for Terrestrial (solid) planets.

I've often imagined Mercury to be a cosmic goldmine, with its apparent richness in metals and its density. I wonder if an astronaut could just walk along and pick up chunks of gold from its surface….

Another interesting find by MESSENGER is that some of the flat plains on Mercury may have been formed by volcanoes, long ago. In particular, MESSENGER imaged a number of volcanoes along the edge of the Caloris Basin, a large impact basin-one of the largest in the Solar System, at 1550 kilometers across.

The news coming out of the innermost region of the Solar System makes me giddy. Too bad I have to wait until 2011 for my next look at Mercury. These things take time.

NASA's MESSENGER spacecraft at Mercury-artist concept.

Photo by: NASA

I've been waiting for the "whole story" on Martian ice at the Phoenix lander site to unfold more completely, but the chemical analyses have not yet run their full courses-so I've decided to widen the focus on this blog to give a status report on current active robotic exploration of planets going on around the Solar System.

Limiting my scope to only planetary spacecraft, the list is still respectable. In no particular order, here's the round-up:

Spirit: Mars Exploration Rover Spirit's activities on the Martian surface have been reduced to save on power, but the robot remains alive. With the arrival of Martian winter, Spirit spends more power running heaters to keep key electronic and power equipment healthy. Spirit remains in the giant Gusev Crater, where it will spend its entire life on Mars.

Opportunity: Exploring a much smaller crater of its own, Victoria Crater-Spirit's twin, Opportunity, continues its investigation of the rock layers of Mars' geological history. As of June 10, Opportunity has clocked in at 7.26 miles of total "roving" on Mars, since its landing back in 2004.

Phoenix: The brand-spankin'-new Mars Phoenix lander has been digging into one of Mars' greatest scientific mysteries: water. Detailed chemical analysis of samples taken at Phoenix's site near the northern polar ice cap is underway, but the big question– is Phoenix standing on frozen Martian water– has been answered: yes.

Mars Reconnaissance Orbiter: The newest orbiter in the Martian fleet continues to send back its extreme-high-resolution imagery and its revealing chemical measurements, as well as to serve as a high-speed data and communication relay for other Mars-exploring robots.

Mars 2001 Odyssey: Credited with detecting the massive amounts of frozen water in Mars' northern hemisphere-the same ice that the Phoenix lander is now scraping at, Mars 2001 Odyssey continues its surveillance of Mars' chemistry and atmosphere.

Mars Express: The European orbiter that launched the ill-fated Beagle II lander has continued on a respectable career of exploration in its own right. Mars Express also helped support the landing of the Phoenix.

Cassini: Saturn's first robot-in-residence, Cassini, has concluded its initial 4-year mission and is now continuing on an extended mission. Cassini has given us unprecedented close-up images and measurements of many of Saturn's stunning moons, its complicated ring system, and the swirling, aurora-touched cloud formations of Saturn itself.

MESSENGER: The first spacecraft to visit the little-understood Mercury since 1975 made its first flyby of that planet last January, and will settle into a permanent orbit in March 2011. Even the few pics it snapped as it hurled by gave us far more detailed images of Mercury than ever before.

New Horizons: Launched a couple years ago on its outward bound, meteoric flight to Pluto, New Horizons has already performed some exploration duty, capturing images and data of Jupiter, Jupiter's volcanic moon Io, and Jupiter's long magnetic "tail." Now in "cruise mode," this little robot will fly past Pluto (dwarf planet; king of the Plutoids) in July 2015.

Voyagers 1 and 2: Do you remember the remarkable voyages of discovery made by the Voyager spacecraft, both launched in 1977? Since completing their primary missions of flying by the Gas Giant planets (Voyager 1 at Jupiter and Saturn, Voyager 2 at all four), these two veterans have continued to operate and send information back to Earth, and are now about 3 times more distant from the Sun than Pluto.

That's the wrap. If I missed anyone, my apologies!

Depiction of a major alignment of
the five visible planets in 1059 BCE.

Photo By Ben Burress

There are some pretty good "lineups" coming soon to skies above you.

First of all, "lineups," or alignments, go on in the heavens all the time, though most often they are alignments of objects too faint to easily notice, if at all. With that said, this summer holds some significant alignments of some of the brightest objects in the sky.

First on my hit list is the upcoming Saturn-Mars "near-miss". Though these two planets are not coming physically close to each other (the closest actual distance they come to each other is about 750 million miles), they will align so closely along the same line of sight that on July 11^th they will appear only ¾ of a degree apart-that's not much greater than the width of a Full Moon. The best time to see this pairing is after sunset on the evenings of July 10, 11, and 12, over the western horizon.

The next big ticket alignment is on August 1^st, when the Moon and the Sun occupy the same spot in the sky-the event we call a Total Solar Eclipse. As it happens, we won't be able to see this eclipse directly from the United States, as it will only be visible in Asia. However, NASA will be broadcasting live coverage of the eclipse from Northern China. We'll be showing NASA's broadcast in our planetarium at Chabot Space and Science Center, in case you'd care to come up and enjoy the spectacle. Don't let the fact that the live event goes on around 4:00 AM keep you away…it's worth getting up for!

A bit further out on the calendar is the September alignment of three planets: Venus, Mars, and Mercury. In the dusky twilight of mid-September evenings the three will be gathering. The closest grouping of the trio is on September 11^th, when they will be within about three degrees of each other-close enough that you can just about cover all three with your thumb. Mercury and Mars won't be very bright in the twilight-but Venus, bright enough to spot easily, can help guide your eye to the other two. Using a pair of binoculars will help a lot-but make sure you don't point them that way until after the Sun sets….

In ancient times (and in some cases not so ancient times), different cultures around the world have viewed alignments like these in different ways. Eclipses-both solar and lunar-were regarded by many cultures as bad omens, or bad occurrences (such as the Sun being devoured by a celestial animal-dragon, dog or other-in the case of a solar eclipse).

Planetary alignments were also given special consideration, sometimes being regarded as auspicious (for good or bad-usually the latter). One major alignment of the five visible planets (February 26, 1953 BCE) was believed to have "mandated" the creation of the Hsia Dynasty in China-the first great Chinese Dynasty. (Then, four centuries later, Mars, Mercury, Jupiter and Saturn apparently conspired to bring down that same dynasty-at least, their alignment on December 20, 1576 BCE was interpreted as an indicator of the dynasty's corruption, and it was overthrown by a revolt of believers…).

However you regard the lining up of celestial bodies (astronomically, astrologically, or aesthetically), these alignments are pleasing to watch, and times to reflect upon the constant and cyclic movement among the heavens. Enjoy….

You're as likely to be struck by lightning
as to have a severe reaction to a vaccine.

I was reading an article in Time last week about parents not vaccinating their children. The story was about how this phenomenon is becoming more widespread.

These kinds of stories are weird to me because vaccines are pretty safe. The risk of an adverse side effect is incredibly small. For example, the risk for anaphylaxis from the Hepatitis B Virus vaccination is around 1 in 600,000. This is about the same risk as being struck by lightning (1 in 700,000).

Of course, the article wasn't talking about known risks. Instead, it was referring to a hypothesized link between vaccines and autism.

People proposed this link when they noticed that cases of autism and the number of vaccinations were rising at the same time. Of course, just because two things happen to occur at the same time, this does not mean they are causally linked. For example, the increase in global temperature is not related to the decrease in the world's populations of pirates (despite what the Pastafarians say).

So how could an increased number of vaccinations cause an increase in the number of cases of autism? I have seen two ideas put forth. The first is that thimerosal is to blame. The second is that there are so many vaccinations now that we are stressing out the body's immune system. Most likely neither idea is valid.

Thimerosal is a mercury-based preservative that used to be used in vaccines. Even though there haven't been any good studies on the effects of thimerosal on brain development, everyone knows mercury is bad for the brain. So the idea behind thimerosal makes some sense.

Back in 2001, vaccine manufacturers decided to eliminate thimerosal from their vaccines. We would predict, then, that cases of autism should go down significantly if thimerosal was linked to autism. They haven't. In fact, in one California study, cases have continued to climb. So thimerosal is most likely not to blame.

Another point that has been made is that there are so many vaccines now that we are stressing out our bodies' immune systems. Again, this concern is unfounded.

Vaccines are injections of viral proteins. Our bodies see the proteins and raise antibodies to them. Then when a virus invades, we have antibodies that recognize the virus and target it for destruction.

It is the number of viral proteins that matter in terms of taxing the body's immune system and not the number of vaccinations. All of the current vaccines put together do not have as many viral proteins as the old smallpox vaccine (150 vs. 200). So the number of vaccines is unlikely to be the issue.

What all of this means is that vaccines are probably not responsible for the significant increase in the number of cases of autism. What is responsible? No one knows for sure.

It may be that the rise just comes from all of us recognizing the symptoms more. Or it could be due to some cause we don't know about or understand.

What we do know is that vaccines save many lives. I assume no one wants to go back to the early 20th century when polio epidemics swept the country. For example, 2,500 cases of polio ended up at one Los Angeles hospital between May and November of 1934. And in 1952, the U.S. had 21,000 cases of paralytic polio.

We can prevent this sort of thing from happening by making sure everyone is vaccinated. And yet there are people who choose to hide behind the people who take the miniscule risk of getting vaccinated.

Is this a matter of free choice? Should parents be allowed to opt out of vaccinating their children even if it risks society at large?

One idea, I suppose, is to have people who choose not to be vaccinated to sign a waiver saying they accept full responsibility for their actions. In practice this would mean that health insurance and the government would not be responsible for their children's health care bills if they become ill with one of the diseases they refused to be vaccinated against.

And if your infant, grandma, or immuno-suppressed cousin came down with a disease these folks refused to be vaccinated against, then you could sue the un-vaccinated for damages. The common good isn't enough to encourage these folks. Perhaps threats to their pocketbook will be.

Infrared image of a zebra from the London Zoo.
Credit: Steve Lowe

Right now I am very excited about the possibility of working on a new small telescope in southern Utah. This telescope was funded by a private donation and will be run by the University of Utah. We even found a mountain top in the middle of nowhere that this telescope will call home.

Why this particular mountain? There are essentially three reasons:

It's dark
It's clear
It doesn't make the stars twinkle

The first two reasons are so obvious that I am almost embarrassed. The last reason is not quite so intuitive. What makes a star twinkle and why do we care? This goes back to a post I made a few months ago.

The basic idea here is that the churning atmosphere blurs your astronomical image. Local geography and weather patterns can either mitigate or exaggerate this effect. It is difficult to predict and many measurements need to be done to determine what is actually happening. Cameras were placed all around southern Utah on various mountain tops to observe the North Star over the course of the year. The mountain top that produced the highest resolution image of the star won the competition. That was Frisco Peak.

The telescope that will be placed on Frisco Peak was built by a very specialized company. This is quite rare–more typical are either large custom-made telescopes or small amateur telescopes. This telescope falls in the middle. It is bought off the shelf but is far superior to the commercially made amateur telescopes.

We are now discussing plans for this telescope, like the type of cameras that should be used. There is a strong interest in building an infrared camera. This allows us to see through large clouds of dust and allows us to see very distant galaxies.

Like most people, I am much more experienced with cameras in the visible spectrum. I work on CCDs in Berkeley and have barely used anything in the infrared. CCDs are made of silicon which is sensitive to light that can be seen with the naked eye (plus a little more red than what can be seen).

However, there is a lot of information in the sky that is too red to be seen with the naked eye and too red to be detected with a silicon detector. New materials are required for detectors in this wavelength range. One of the major new materials for infrared detectors is a blend of mercury, cadmium and telluride, usually called Mer-Cad-Tell in the astro community. The wavelength range of the detector can be tuned by changing the amount of mercury in the blend.

Clearly, a lot of the legwork has been done for this new telescope. We have the funding, we have a vendor, and we have a location. Now all that's left is to prioritize our science goals and to figure out how to get our hands on some mer-cad-tell.

Kyle S. Dawson is engaged in post-doctorate studies of distant supernovae and development of a proposed space-based telescope at Lawrence Berkeley National Laboratory.

Last week on QUEST, we took a look at the history of the San Francisco Bay's most dangerous toxin: mercury. This week, now that the mercury is here in the bay, how is it affecting us? The obvious place to go was the Berkeley Marina, one of the bay's most popular fishing spots. On the day I visited, halibut season had just begun and, even on a Monday morning, the pier was lined with anglers. Halibut contains high levels of mercury, just like other big SF Bay fish but – as you hear in the piece – you wouldn't know it from talking to the fishermen out that day.

Of course mercury is a problem in many big fish we eat, not just the ones in the San Francisco Bay. Dr. Jane Hightower is one of the leading local doctors diagnosing various levels of mercury poisoning in her patients – many of whom, as she says, do their fishing at places like Whole Foods. We only had time to use a short piece of that interview in the actual story, but anyone who eats fish will want to hear more from Dr. Hightower. A longer version of that interview – including Dr. Hightower’s surprising views on kid staples like canned tuna fish – is right here.

You may listen to the "Mercury in the Bay – Part 2″ Radio report online, as well as find additional links and resources.

Amy Standen is a Reporter for QUEST and Radio News at KQED-FM.