With a huge and still-growing catalog of exoplanets, researchers are eager to take the next steps: trying to infer what conditions are like on them, either by imaging them directly or by capturing the light that has passed through their atmosphere. Both are substantial challenges, given the presence of stars that are far, far brighter than light that has come to us via the planet.

While telescopes can be fitted with devices called coronagraphs that block out much of a star's light, there are limits to their effectiveness, caused by noise from subtle variations in the telescope's configuration and pointing between observations. Now, researchers have developed a new software package that optimizes a physical model of the telescope in a way that allows us to better model these differences, producing low-noise imaging of exoplanets.

Point spreads

Central to this work is the concept of a point spread function. If you use a telescope to image a single point of light, it will not appear that way in the actual image. Instead, it will be slightly blurry and spread out, due to imperfections in the telescope hardware and the limits of our ability to keep it pointed accurately through the time it takes to image something. The mathematical description of how a telescope distorts a point of light is called its point spread function.

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It’s a regrettable reality that there is never enough time to cover all the interesting scientific stories we come across. So every month, we highlight a handful of the best stories that nearly slipped through the cracks. October’s list includes an epigenetic mechanism for why large dogs age faster than smaller ones; physicists who trapped a single particle of antimatter for months; and invisible tattoo inks that only show up under UV light.

Why large dogs age faster

In many mammalian species, larger creatures tend to have longer lifespans. Mice, for instance, live an average of just two years, while some whales can last for as long as 200 years. Dogs, however, buck this pattern; larger dogs tend to age faster and die younger than smaller ones, which makes canines an ideal model for biologists to study to learn more about aging in general. Arizona State University scientists report that these lifespan differences seem to be due to so-called "jumping genes," according to a paper published in the journal Science.

The authors used data from 864 dogs collected in the Dog Aging Project to map patterns of DNA methylation (which influences how much certain genes are turned on or off) across the entire genome. It's part of the epigenome, whose markers can change over time in response to stress and other environmental factors. Genetic sequences, by contrast, are largely fixed. So DNA methylation is a good chemical indicator of aging and DNA regulation.

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The Hubble Space Telescope still shines in the eyes of astronomers after 36 years in orbit, but it is not as nimble as it once was. Left alone, the observatory will plunge back into the atmosphere in the early-to-mid-2030s, closing the book on one of the most famous scientific instruments of the century.

NASA last raised the orbit of Hubble in 2002, when the Space Shuttle Columbia visited the observatory for a servicing mission. The final shuttle servicing flight in 2009 did not reboost the telescope's orbit, and with the retirement of the shuttle fleet two years later, Hubble has steadily lost altitude with no way to stave off eventual destruction.

The space agency released a Request For Information (RFI) on Thursday asking commercial companies for ideas on how to reboost, service, or conduct a controlled disposal of Hubble. Responses are due November 30. Specifically, NASA is looking for information about companies' current and near-term capabilities for capturing Hubble and boosting it to an altitude of at least 373 miles (600 km), enhancing the telescope's performance, or guiding Hubble to a controlled reentry.

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