NASA bounces laser beams off of Lunar Reconnaissance Orbiter
After a decade of failed attempts, scientists successfully bounced photons off of a reflector aboard the Lunar Reconnaissance Orbiter, some 240,000 miles from Earth.
- Laser experiments can reveal precisely how far away an object is from Earth.
- For years scientists have been bouncing light off of reflectors on the lunar surface that were installed during the Apollo era, but these reflectors have become less efficient over time.
- The recent success could reveal the cause of the degradation, and also lead to new discoveries about the Moon's evolution.
NASA's Lunar Reconnaissance Orbiter (LRO) has been orbiting the Moon about a dozen times per day since 2009. The craft carries six high-tech instruments that have helped scientists create detailed maps of the moon, and learn more radiation and temperatures on the lunar surface.
But the craft also carries a rather simple instrument: a reflector the size of a paperback novel.
Over the past decade, scientists have been shooting laser beams from Earth to the LRO's reflector, some 240,000 miles away, hoping to catch a return signal. On Monday, NASA scientists and their French colleagues announced that they successfully received that return signal for the first time.
What can scientists learn by bouncing lasers off the LRO? For one, it reveals precisely how many seconds it takes for photons to travel there and back — an average of 2.5 seconds. Scientists can use this duration to tell exactly how far away an object is. Also, by measuring tiny fluctuations in the duration, they can study subtle movements of the Moon.
A close-up photograph of the laser reflecting panel deployed by Apollo 14 astronauts on the Moon in 1971.
The technology isn't quite new. During the Apollo era, astronauts installed on the lunar surface five reflecting panels, each containing at least 100 mirrors that reflect back to whichever direction it's coming from. By bouncing light off these panels, scientists have been able to learn, for example, that the Moon is drifting away from Earth at a rate of about 1.5 inches per year.
"Now that we've been collecting data for 50 years, we can see trends that we wouldn't have been able to see otherwise," Erwan Mazarico, a planetary scientist from NASA's Goddard Space Flight Center in Greenbelt, Maryland, said. "Laser-ranging science is a long game."
NASA's Lunar Reconnaissance Orbiter (LRO)
But the long game poses a problem: Over time, the panels on the Moon have become less efficient at bouncing light back to Earth. Some scientists suspect it's because dust, kicked up by micrometeorites, has settled on the surface of the panels, causing them to overheat. And if that's the case, scientists need to know for sure.
That's where the recent LRO laser experiment comes in. If scientists find discrepancies between the data sent back by the LRO reflector and those on the lunar surface, it could reveal what's causing the lunar reflectors to become less efficient. They could then account for these discrepancies in their models.
Studying the Moon's core
More precise laser experiments could also help scientists learn more about the moon's core. By measuring tiny wobbles as the Moon rotates, past laser experiments revealed that the satellite has a fluid core. But inside of that fluid could lie a solid core — one that might've helped to generate the Moon's now-extinct magnetic field.
However, confirming that hypothesis will require more precise measurements — and the continued success of laser experiments involving the LRO, or reflecting panels installed on the Moon during future missions.
"The precision of this one measurement has the potential to refine our understanding of gravity and the evolution of the solar system," Xiaoli Sun, a Goddard planetary scientist who helped design LRO's reflector, told NASA.
Researchers have just discovered the remains of a hybrid human.
90,000 years ago, a young girl lived in a cave in the Altai mountains in southern Siberia. Her life was short; she died in her early teens, but she stands at a unique point in human evolution. She is the first known hybrid of two different kinds of ancient humans: the Neanderthals and the Denisovans.
These thought leaders, founders, and entrepreneurs are propelling the kind of future we want to be a part of.
- The tech industry may be dominated by men in terms of numbers, but there are lots of brilliant women in leadership positions that are changing the landscape.
- The women on this list are founders of companies dedicated to teaching girls to code, innovators in the fields of AI, VR, and machine learning, leading tech writers and podcasters, and CEOs of companies like YouTube and Project Include.
- This list is by no means all-encompassing. There are many more influential women in tech that you should seek out and follow.
Most said they want to act on their desire someday. But do open relationships actually work?
- The study involved 822 Americans who were in monogamous relationships at the time.
- Participants answered questions about their personalities, sexual fantasies, and intentions to act on those fantasies.
- Research suggests practicing consent, comfort, and communication makes open relationships more likely to succeed.
Consensual non-monogamy fantasies<p>For the new study, published in <a href="https://link.springer.com/article/10.1007/s10508-020-01788-7" target="_blank">Archives of Sexual Behavior</a>, researchers asked 822 people in monogamous relationships to:</p><ul><li>Describe their favorite sexual fantasy, defined as "mental images you have while you are awake that you find to be sexually arousing or erotic."</li><li>Select which themes apply to that fantasy, such as having sex with multiple people at the same time, experimenting with taboos, or engaging in a sexually open relationship.</li><li>Answer whether they intended to carry out these fantasies, and discuss them with their partner.</li><li>Complete assessments on relationship satisfaction, erotophilia and personality, as measured by the Big Five Personality inventory.</li></ul><p>The results showed that 32.6 percent of participants said being part of a sexually open relationship was "part of their favorite sexual fantasy of all time." More surprising is that, of that one-third, 80 percent said they want to act on this fantasy in the future.</p>
Pretzelpaws via Wikipedia Commons<p style="margin-left: 20px;">"The present research confirms the important distinction between sexual fantasy and sexual desire in that not everyone wanted to act on their favorite sexual fantasy of all time," study author Justin J. Lehmiller told <a href="https://www.psypost.org/2020/09/one-third-of-people-in-monogamous-relationships-fantasize-about-being-in-some-type-of-open-relationship-study-suggests-58102" target="_blank">PsyPost</a>. "This suggests that fantasies may serve different functions for different people."</p><p>Even though most participants said they want to act out their fantasy in the future, far fewer reported acting out sexual fantasies in the past. Other findings included:</p><ul><li>Men were more likely to fantasize about CNMRs.</li><li>So were people who scored high in <a href="https://en.wikipedia.org/wiki/Erotophilia#:~:text=Erotophilia%20is%20a%20personality%20trait,ranging%20from%20erotophobia%20to%20erotophilia." target="_blank">erotophilia</a> and sociosexual orientation.</li><li>The psychological predictors of fantasizing about CNMRs differed from predictors about infidelity fantasies.</li></ul>
Do open relationships work?<p>A <a href="https://www.tandfonline.com/doi/full/10.1080/00224499.2019.1669133" target="_blank">2019 study</a> from psychologists at the University of Rochester suggests it <em>is </em>possible<em>, </em>but especially when both partners practice a trio of behaviors: consent, communication, and comfort — or, the Triple-C Model.<br></p>But the study also suggests not all forms of open relationships are equally viable. For example, people in one-sided CNMRs — where one partner stays monogamous, the other seeks outside sexual relationships — were nearly three times more dissatisfied in their relationships than the monogamous group <em>and </em>the consensual non-monogamous group.
The results of this study showed depressive symptoms being highest in adolescence, declining in early adulthood and then climbing back up again into one's early 30s.