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NASA

Human exploration of Mars won't be easy. Jennifer Stern, a space scientist for NASA and Martian expert, talks about the differences between Earth and Mars during a recent astronomy forum at Southern.

For those of us old enough to remember the Apollo space program of the 1960s and ’70s, the images of man walking on the Moon will forever be ingrained in our memories. It was a time of excitement, accomplishment, wonder and promise. After all, if we could make it to the Moon, then interplanetary travel could not be too far away, right? And Mars would logically be the next stop with astronauts walking on the Red Planet perhaps as soon as 1984 or 1990…but certainly by the turn of the century.

Well, obviously that didn’t happen. The national enthusiasm for the space program seemed to wane throughout the tumultuous 1970s. Budget restrictions limited NASA programs. And let’s face it, in the afterglow of successful missions to the Moon, maybe we underestimated what a similar voyage to Mars would entail.

The truth is, such a manned flight to and back from Mars is a huge undertaking. By comparison, a trip to the Moon is about 240,000 miles in length. A journey to Mars – even when Earth and Mars are in their closest proximity to each other – is about a 35 million-mile expedition. Flying to the Moon took about three days. A human flight to Mars, based on current technology, would take about six months, according to Jennifer Stern, a NASA space scientist who spoke at a recent forum at Southern, “Missions Possible: A Manned Flight to Mars, & Finding ‘New Earths’ in the Milky Way Galaxy.”

The forum examined both the Kepler Mission (the search for Earth-like plants in the Milky Way Galaxy), and what a manned flight to Mars would entail.

Part I of this series focused on the Kepler Mission. Today, we look at a future trip to Mars.

“This (manned flight to Mars) is going to happen in the next 20 years,” Stern said.

She said that while probes of the planet are of great value, it is only through human exploration of the planet that we can fully understand whether life could have existed on Mars, or might currently exist on Mars. “We need boots on the ground,” Stern said. “We need the human cognitive ability to make decisions, to take samples, to put things into context.”

She stressed that human exploration of Mars is a complicated endeavor. She pointed to three major challenges:

  • Getting and landing on Mars. – Mars has a very thin atmosphere, and it is therefore difficult to land large objects on the planet because there isn’t an adequate atmosphere to slow things down.
  • Living in space. – On Earth, people are protected against radiation by a magnetic field. But in space, the human body is exposed to very high doses of radiation. Part of the challenge is to assess how much radiation the human body can tolerate and how that level can be mitigated. Also, because there is no gravity in space, people lose bone density and muscle mass. That has to be addressed, as well.
  • Living on Mars – Scientists must learn how to use the natural resources of Mars to make oxygen, grow food, etc.

The audience at the forum included 650 people – including 425 high school students and 30 middle school kids. It also included 45 or so individuals from nearby senior centers. While there was a contrast in age of the audience, there wasn’t much difference in enthusiasm. Young, middle-aged and old alike made a point of asking questions of the speakers.

Kids growing up in the 1960s and early ’70s were excited about the prospect of going to the Moon. Some of them were in the audience. And watching the engaged high school and college students at the forum, you have to think that some of that enthusiasm will remain when these 15- and 20-year-olds are 30- and 35- and 40-year-olds, about the time that the first rocket to Mars – with humans aboard – is likely to be launched.

Stern said that those currently in high school or college are going to be part of this new mission in some way. She said that while only a small number of people will directly be involved in a Martian trip, many will be involved in the technology associated with it. And she said everyone will benefit from the research that’s done on bone density, radiation and other health and technological matters affiliated with the project. “It’s going to help the quality of life on Earth,” she said. “It’s going to help keep us strong as we age.”

And you have to wonder what the kids of the 2030s will be thinking when they see astronauts take those first steps in the Red Planet. Will they view that milestone the way that kids of the 1960s viewed Neil Armstrong and “Buzz” Aldrin walking on the Moon?

Time will tell, of course. But if the enthusiasm displayed by the kids of 2015 is any indication, it appears to be a likely prospect.

The high schools attending the forum were:

  • Abbott Tech (Danbury)
  • Amity (Woodbridge)
  • Berlin
  • Derby
  • East Haven
  • Haddam-Killingworth (Higganum)
  • Hand (Madison)
  • Hillhouse (New Haven)
  • Lyman Hall (Wallingford)
  • Maloney (Meriden)
  • Morgan (Clinton)
  • Newtown
  • North Haven
  • Stratford

The audience also included middle school students from the Columbus Family Academy in New Haven;  senior center organizations from Branford, Guilford and New Haven; members of Southern’s campus community and folks from the general public.

Venus is often referred to as Earth’s “sister planet.”

After all, they orbit the same sun. Venus is just a bit smaller than Earth. And the two are only about 26 million miles away from each other – veritable next-door neighbors in the cosmos.

But other than size and proximity, the two planets have little in common. The surface temperature on Venus is nearly 900 degrees Fahrenheit. (And you thought Florida was hot in the summer.) The atmosphere is almost entirely made of carbon dioxide. In short, astronomers are fairly certain life doesn’t exist on Venus.

So, other than perhaps the courtesy title of “sister,” you can cross Venus off the sibling list. In fact, the closest thing Earth may have to a solar system sibling would have to be Mars. While there is still no proof, some scientists believe it’s possible there is some form of life on the Red Planet, although it would almost certainly be microbial – bacteria and viruses than we would refer to on Earth as germs.

But astronomers have not given up hope that life – perhaps closer to what we have come to know on Earth — might exist on another planet outside of our solar system. In fact, NASA is taking steps to try to answer that age-old question with its Kepler mission. The Kepler spacecraft is in orbit around the sun, currently about 40 million miles away from Earth. From the spacecraft, the brightness of about 145,000 stars in a swath of the Milky Way Galaxy is being monitored. A very slight reduction in the brightness of an individual star is an indication that a planet might be orbiting around it.

Kepler-22b, the first confirmed planet outside our solar system to be orbiting its sun at a distance hospitable to life, is shown here in an artist's rendering of what it might look like. It is located 600 light years away and its radius is about 2.4 times that of Earth.Image credit: NASA/Ames/JPL-Caltech
Kepler-22b, the first confirmed planet outside our solar system to be orbiting its sun at a distance hospitable to life, is shown here in an artist’s rendering of what it might look like. It is located 600 light years away and its radius is about 2.4 times that of Earth.
Image credit: NASA/Ames/JPL-Caltech

Through the Kepler findings, astronomers are able to take a closer look at those “potential planets” to determine if they actually exist, and if so, how far they are away from their sun, according to Elliott Horch, associate professor of physics at Southern. Ground-based telescopes and equipment are used for this purpose. (One of the Earth-based devices used to prove or disprove the existence of a planet was actually developed by Horch with funding from the National Science Foundation.)

A “sweet spot” distance between a planet and its sun would increase the chances of the surface temperature on that planet being hospitable to life. That distance – known scientifically as a “habitable zone”– varies based on multiple factors, but a requirement is that water can exist as a liquid on that planet. The Earth is an average of about 93 million miles away from the sun.

Horch says the Kepler mission is already producing fascinating results. “It really is a remarkable project – one that may help us one day answer the age-old question, ‘Are we alone?’”

He points to several Kepler accomplishments:

  • A total of 105 planets have been found so far that are within the potential “life zone” distance from their sun. That number is expected to rise significantly in the months and years ahead. The first of these 105 “confirmed planets” orbiting in this habitable zone is known as Kepler-22b, located about 600 light years from the Earth.
  • About 2,700 stars are being closely studied as possibly having planets that could sustain life.
  • Based on results from the project so far, experts estimate that about 16 percent of stars similar to our sun have a planet similar in size to the Earth orbiting it.

So what? Just because a planet orbits a star within a certain range doesn’t prove that life exists on it, let alone any form of intelligent life, right?

That’s correct. But as Horch points out, it’s a significant step toward finding out. He notes that astronomers could then hone in more closely on those potential “Earth-like planets” to determine if life is likely, such as by conducting more research on the average density of those planets.

“After that, things gets much more difficult,” Horch acknowledges. “But perhaps a next-generation satellite or satellite array could determine a planet’s bulk atmospheric properties or even take an image of the planet.”

And those actions would move us closer, by far, in determining whether or not we are alone in the universe.

Do you think life exists on other planets? And if so, is there intelligent life out there?