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‘It is within our grasp’

first_imgWith a bit of luck and a new space telescope, within five years we could know the answer to a question that humanity has pondered for millennia: Is there life beyond Earth?With initial results from the planet-finding Kepler satellite to be released in coming months, and the prospects of taking a closer look at those planets in the coming years with the Webb space telescope, Harvard-Smithsonian Center for Astrophysics (CfA) astronomer Lisa Kaltenegger said the chance for discovery of small, rocky Earth-like planets with the potential to harbor life is pretty good.“It is within our grasp to do this,” Kaltenegger said during a talk Wednesday (Sept. 15) sponsored by the Harvard Origins of Life Initiative.Kaltenegger’s enthusiasm for her subject was reflective of the current excitement among astronomers who’ve spent years searching for planets around other stars. A major focus has been to answer the question of whether there are other Earth-like planets out there and whether those planets might harbor life.Recent advances in technology and technique have put those answers just beyond our fingertips. Kaltenegger’s optimism stands on three scientific legs.The first is the Kepler Mission. Kepler is a space telescope launched in 2009 that is dedicated to finding small, rocky planets around other stars. Like Earth, such planets are thought to have the best chance of harboring the conditions favorable to life. In June, Dimitar Sasselov, co-principal investigator of Kepler’s science mission and professor of astronomy at the CfA, announced that Kepler has already found more than 700 candidate planets. Researchers are conducting follow-up studies and expect to announce how many of them are confirmed in the coming months.The second leg will be the James Webb Space Telescope. Set to be launched in 2014, Webb has a 6.5-meter mirror, which Kaltenegger said is large enough to let scientists take a closer look at the planets found by Kepler.The third leg is the ability of scientists to read the atmosphere of planets around other stars. As first demonstrated in 2007 by Harvard astronomy professor David Charbonneau and colleagues, researchers can measure the light coming from the star as the planet passes in front of it. By looking at how the starlight is altered when it passes through the planet’s atmosphere, scientists can tell what the atmosphere is made of.The presence of certain compounds in the atmosphere is indicative of life, Kaltenegger said, because on Earth at least, the compounds are either important for life or present in the atmosphere because of living things. One of the biggest is oxygen, which is released by plants and microbes during photosynthesis. Other chemicals that are potential signatures of life include methane, carbon monoxide, and nitrous oxide, which are produced by bacteria. Water vapor is another important signature to look for, because water is important for life on Earth.“I love biota, but what I love even more is biota that modifies the atmosphere,” Kaltenegger said.Other factors will be important as well, Kaltenegger said. A planet’s orbit has to be in the so-called Goldilocks Zone — not too close to the star, which would make it too hot to support life, and not too far away, which would make it too cold. Where the planet is in its evolution is important as well, Kaltenegger said. The composition of the Earth’s atmosphere has changed over time, with six very distinct epochs that would show up differently to observers looking at the Earth from far away. Fortunately, Kaltenegger said, the Earth’s example has shown that the conditions favorable to life aren’t fleeting; some signs have existed in the Earth’s atmosphere for two billion years.Major volcanic events may also be possible to detect, Kaltenegger said — explosions 10 to 100 times the Mount Pinatubo eruption should be detectable. Since volcanism and plate tectonics are thought to be important geologic processes supporting life, Kaltenegger said, they are another indicator that can be viewed from far away.last_img read more

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Blocking fear

first_imgSince the campus was cleared in response to the COVID-19 pandemic, Adeleye is back home in Memphis, though not removed from Alzheimer’s research or even patients. She can still analyze data from afar. And her best friend from childhood, whose grandmother was starting to show signs of dementia, asked the neuroscience major for advice. “You’re never prepared,” Adeleye said. But, “It’s not just you going through that experience but all those around you.”On the Harvard volleyball team, Adeleye played middle blocker. The player in that position — center court, closest to the net — is typically loud and enthusiastic, the team trumpeter. “I’m naturally a really loud person,” Adeleye said, “so it fit well with my personality.” When she returned to the court in September 2019 after almost a year of recovery, the 6-foot-1-inch senior achieved career highs of 14 kills and seven blocks against Sacred Heart.Asked if juggling athletics, science, and a brain injury ever felt overwhelming, Adeleye said, “Anything you’re going to do is going to be challenging. Anything worth doing is going to have some obstacles.”Adeleye is looking for a job as a neurology clinic researcher and will apply to medical school in two years. This is one in a series of profiles showcasing some of Harvard’s stellar graduates.Sope Adeleye went up for a block and everything went black.“I just got hit in the face,” she said, describing that fateful moment during volleyball practice in October 2018.Adeleye had performed that jump thousands of times before, but this time her head got there faster than her hands.She was diagnosed with a severe concussion. The neuroscience major knew better than most that head traumas come with a shadowy threat — an increased risk of dementia.“So much of where I’ve gone in life is based on what I’ve been able to do with my brain,” she said. “That’s so much of who I am, and the idea of losing that, slowly but surely, that sense of self, the sense of who you are …”Growing up in Memphis, a younger sister to two athletic brothers and the daughter of two medical professionals — her father is a nephrologist and her mother a nurse practitioner — Adeleye knew she wanted to be both an athlete and a doctor. In addition to volleyball, she played basketball, soccer, and tennis.Around the same time, Adeleye said, she fell in love with the brain — a sheep’s brain to be exact. The summer before her junior year in high school, she enrolled in a neuropsychology course at Columbia University. There, she dissected a sheep brain and got her first look at how it controls an animal’s behaviors, learning ability, and sensation.“You have this thing in your head that literally controls everything,” Adeleye said. “We know so much about it, but we also know just so little.”,Adeleye decided to study neuroscience before she enrolled at Harvard, but she didn’t choose a research track until after her concussion. In spring of 2019, she joined Tracy Young-Pearse’s lab at Brigham and Women’s Hospital where she studies the neuronal characteristics that differentiate healthy individuals from those with late onset Alzheimer’s disease.“With studying human disease and the brain,” she said, “you can’t go two steps without hearing about Alzheimer’s disease. It’s estimated that 40 million people have Alzheimer’s disease right now worldwide and the number is only going to increase exponentially by 2050 because of the aging population.”In 2018, Adeleye started volunteering with the nationwide program Alzheimer’s Buddies (the Phillips Brooks House Association runs Harvard’s chapter). Almost every Sunday, she and the other volunteers visited a nursing home to spend an hour chatting with a “Buddy,” a patient living with a form for dementia. Though some patients have family members and friends nearby who come to visit, some live in relative isolation, which can aggravate their disease. Adeleye said the program taught her how much it means for someone to just be there. “You have this thing in your head that literally controls everything. We know so much about it, but we also know just so little.” — Sope Adeleye ’20last_img read more

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