Smithsonian.com

Has it really been 10 years since we were all panicking about the Y2K bug? Yes, it’s the end of another decade, and as with any good publication, we’re going to overload you with lists as we pause to reflect. What’s first? The 10 greatest moments in science, in ascending order:

Hurricane Katrina (credit: Jeff Schmaltz, MODIS Rapid Response Team, NASA/GSFC )

10. Hurricane Katrina track forecasting: Lost in the stories of devastation across Mississippi and Louisiana, especially New Orleans, following Katrina’s landfall in 2005 was the story of the NOAA forecasters’ success. “The accuracy and timeliness of National Weather Service and National Hurricane Center forecasts prevented further loss of life,” wrote a U.S. House of Representatives Select Committee in 2006. Government hurricane scientists accurately predicted the storm’s track five days before landfall, giving what should have been ample time to governments and individuals to prepare.

9. Gene therapy: The idea of inserting a gene into a person to cure a disease has been around for ages, but it had hit a low point in 1999 with the death of gene therapy trial participant Jesse Gelsinger. In 2008, though, scientists used gene therapy to improve the eyesight of individuals with a kind of blindness called Leber’s congenital amaurosis. Other researchers have had success using the method to treat adrenoleukodystrophy and a type of severe combined immunodeficiency.

8. Solving the Poincaré Conjecture: Henri Poincaré came up with his famous problem—which is about the topology of a 3-dimensional sphere—at the beginning of the 20th century. It remained unsolved until Grigori Perelman published a series of papers in 2002 and 2003. Years of review followed, and Perelman’s proof was confirmed in 2006. That year, he was awarded a Fields Medal, the top honor in mathematics, but he turned it down.

7. “Intelligent design” struck down in a Pennsylvania court: When the Dover, Pennsylvania school board mandated the introduction of intelligent design into 9th-grade biology classes in the form of a disclaimer to be read to students, 11 parents sued. The case went to court in 2006, and in December, the judge ruled in favor of the parents, writing that intelligent design was not science and the disclaimer conveyed “a strong message of religious endorsement,” which violated the Constitution’s establishment clause.

A trench dug by Phoenix shows ice as it sublimates over days (credit: NASA/JPL-Caltech/University of Arizona/Texas A&M University)

6. Evidence of water on Mars: The satellite evidence for water on Mars was always intriguing—there appeared to be dry river beds and gullies. The NASA rovers Spirit and Opportunity found more clues, like hematite and silica, minerals that form in the presence of water. Real “proof,” though, came from the Phoenix lander, which in June 2008 found a few crumbs of ice that were buried beneath the surface layer of dirt and that sublimated over the next several days.

5. Clinical trials show hormone replacement therapy (HRT) has problems: For six decades, doctors prescribed a cocktail of hormones to older women to alleviate the symptoms of menopause, such as hot flashes and weight gain. Anecdotal evidence and comparison studies suggested that HRT protected women against heart disease and osteoporosis. That all fell away in 2002, though, with the release of results from two large, double-blind, placebo-controlled clinical trials by the Women’s Health Initiative that showed women taking HRT had a higher risk of breast cancer, heart disease and strokes. Why was this a great moment in science? Because science—in the form of clinical trials—worked, exposing the flaws in HRT and protecting millions of women.

4. Climate change research wins a Nobel Peace Prize: The Nobel committee awarded the 2007 Peace Prize to the Intergovernmental Panel on Climate Change (and Al Gore) “for their efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change.”

3. A spacecraft maps the remnants of the Big Bang: With the Wilkinson Microwave Anisotropy Probe (WMAP), launched in 2001, scientists mapped the oldest light in the universe (left over from the Big Bang), determined the age of the universe (13.73 billion years old), and determined that dark matter constitutes 23.3 percent of the universe and dark energy 72.1 percent.

2. The discovery of “Ardi,” our ancestor: The fossils of Ardipithecus ramidus were actually discovered in Ethiopia in 1994, but they didn’t come fully into the light of the science world until earlier this year. Ardi is older than Lucy (an Australopithecus) but unmistakably a hominin, with bits that are rather chimp-like but others that are even closer to humans. This discovery gives important insight into human evolution over the last six million years.

1. The sequencing of the human genome: Genome sequencing has become almost common, with new species being added to the list (the corn genome was published less than two weeks ago). But arguably the most important, sequencing of the human genome was completed in 2003, which gave scientists an important tool for research on human biology and disease.