Universe Today

June 16, 2013December 23, 2015 by Ken Kremer

Cosmonaut Valentina Tereshkova; 1st Woman in Space 50 Years Ago! Ready for Mars

Soviet Cosmonaut Valentina Tereshkova was the first woman launched to space 50 years ago aboard Vostok on June 16, 1963. Credit: Roscosmos

50 Years ago today, Soviet Cosmonaut Valentina Tereshkova made history and became the first woman ever fly in space, when she launched aboard the Vostok-6 capsule on June 16, 1963.

The then 26 year old Tereshkova blasted off from the Baikonur Cosmodrome – following in the historic footsteps of Cosmonaut Yuri Gagarin, the first human to fly in space for a single orbit in 1961.

Her mission was far longer, lasting nearly 3 days (70 hours 50 minutes) for a total of 48 orbits of Earth at altitudes ranging from 180 to 230 kilometers (110 x 144 mi). She conducted biomedical & science experiments to learn about the effects of space on the human body, took photographs that helped identify aerosols in the atmosphere and manually piloted the ship.

“Hey, sky! Take off your hat, I’m coming!” she said in the seconds prior to liftoff.

Vostok-6 was her only space mission.

First woman in space Soviet cosmonaut Valentina Tereshkova is seen during a training session aboard a Vostok spacecraft simulator on January 17, 1964. Credit: AFP Photo / RIA Novosti

But today at age 76, Tereshkova is ready to forget retirement and sign up for a truly grand space adventure – a trip to Mars.

“I am ready [to go to Mars],” she said in remarks on the occasion of the 50th anniversary of her June 16, 1963 blastoff, according to Roscosmos, the Russian Federal Space Agency. Apparently Mars is her favorite planet!

“Of course, it’s a dream to go to Mars and find out whether there was life there or not,” Tereshkova said. “If there was, then why did it die out? What sort of catastrophe happened?”

Valentina Tereshkova today at age 76 - ready for a Mission to Mars. Credit: RIA Novosti — Valentina Tereshkova today at age 76 – ready for a Mission to Mars. Credit: RIA Novosti

Tereshkova’s landmark flight on Vostok-6 was made ever more historic in that it was actually a joint space mission with Vostok-5; which blasted off barely two days earlier on June 14 with fellow Soviet cosmonaut Valery Bykovsky.

Vostok-5 and Vostok-6 flew within 5 kilometers (3 miles) of one other at one point. They spoke to each other by radio as well as with the legendary Soviet Premier Nikita Krushchev. Her call sign was “Seagull”. Bykovsky’s call sign was “Hawk”.

Sergei Korolyov, the father of the Soviet space program, called her “my little seagull.”

Korolev wanted to launch a woman to space to score another spectacular first for the Soviet Union at the height of the Cold War with the United States.

So she had been selected as a member of the cosmonaut corps just a year earlier in March 1962 along with four other female candidates. Teseshkova was the only member of that female group ever to achieve orbit.

Sergei Korolev, founder of the Soviet Space program, and Valentina Tereshkova. Credit: Roscosmos

Tereshkova, a textile factory worker, was chosen in part because she was an expert parachute jumper – a key requirement at that time since the Vostok capsule itself could not land safely. So the cosmonauts had to eject in the last moments of the descent from orbit at about 7,000 m (23,000 ft) and descend separately via parachute.

It would take nearly two decades before another woman – also Soviet- would fly to space; Svetlana Savitskaya in 1982.

The first American female space flyer – Sally Ride – finally reached orbit a year later in 1983 aboard the Space Shuttle.

To date, woman comprise about 10% of the people who have flown to space-57 out of 534.

Today, June 16, there are two women orbiting Earth out of 9 humans total – NASA Astronaut Karen Nyberg aboard the International Space Station and Chinese astronaut Wang Yaping aboard Shenzhou 10.

Vostok-6 was the last of the Vostok spacecraft series.

Bykovsky flew a total of 5 days and 82 orbits. He landed 3 hours after Tereshkova on June 19.

Tereshkova became an instant heroine upon landing, a ‘Hero of the Soviet Union’ and will forever be known as the ‘First Lady of Space.’

On June 14, Russian Television aired a special 50th anniversary program celebrating the flights of Vostok-5 and Vostok-6 – “Valentina Tereshkova – Seagull and the Hawk”

And don’t forget to “Send Your Name to Mars” aboard NASA’s MAVEN orbiter- details here. Deadline: July 1, 2013

Ken Kremer

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Learn more about Mars, Curiosity, Opportunity, MAVEN, LADEE and NASA missions at Ken’s upcoming lecture presentations

June 23: “Send your Name to Mars on MAVEN” and “CIBER Astro Sat, LADEE Lunar & Antares Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA, 8 PM

June 14, 2013December 23, 2015 by Nancy Atkinson

Join the 32-Hour Hangout-A-Thon for Space Education and Outreach

In the latest budget proposal for NASA, it appears as though one of NASA’s jewels — education and pubic outreach – is going to take a huge hit. The proposal seeks to slash NASA’s education budget by about a third, going from $137 million to $94 million. Also proposed is an initiative to combine (and in effect, water down) what NASA does by consolidating different educational efforts across the nation.

The American Astronomical Society issued a statement saying that the proposed cuts “would dismantle some of the nation’s most inspiring and successful STEM education assets.”

Dr. Pamela Gay, who heads up a big educational and citizen science effort with Cosmoquest, has written passionately about how these proposed cuts as well as the current sequestration of US governmental agencies will affect not only her work with education and citizen science, but educational programs for schools and universities across the US. Additionally, people who work in these areas face job losses.

So faced with funding cuts, the Cosmoquest team has decided to try an old-fashioned tele-thon (remember Jerry Lewis and his MDA telethons every year?) using new technology.

On June 15-16, Pamela Gay and Nicole Gugliucci are hosting a 32-hour Google Hangout on Air – a Hangout-a-thon – to raise money to support public engagement in science.

It starts at Noon EDT, 16:00 UTC on June 15, 2013 and will feature guests like Phil Plait (the Bad Astronomer), NASA scientists and educators, the cast of Beyond the Wall, Mat Kaplan from Planetary Radio, and our very own Fraser Cain. Yours truly might make an appearance as well, beaming in from the middle of nowhere in Minnesota.

A complete schedule of guests and events can be found here.
Facebook Event Page

If you aren’t able to donate money, Pamela has written a great post about all the different things you can do to help.

As the CosmoQuest team said, they want to make sure astronomy education survives and remains strong. “While one team, and one telethon can’t fix everything, they hope this event can raise awareness, while protected one small corner of astronomy research and education.”

Education and technology are so important for our world’s future; if you can support this effort in any way, it would be greatly appreciated.

You can make a donation (tax deductible in the US where laws allow) through PayPal here.

The main G+ page for the Hangout-A-Thon

June 14, 2013December 23, 2015 by Nancy Atkinson

Astrophotos: The Galactic Desert

A 12-photo panoramic of the milky way arching over Saguaro National Park in Tucson, Arizona. Credit and copyright: Sean Parker/Sean Parker Photography.

The desert provides some of the most stunning landscapes and skycapes, as evidenced by two recent astrophotos from Universe Today readers. The gorgeous lead image by Sean Parker of Tucson, Arizona is a 12-image panoramic view of the Milky Way arching over Saguaro National Park in Tucson, Arizona. Sean noted on Flickr that if you live in Tucson, you can see this photo in a 12×36 frame at Black Crown Coffee Co for the next 3 weeks during his Astrophotography Exhibition. If you go, tell him Universe Today sent you!

The stunning image below is a frame from a timelapse being worked on by Ken Brandon of California. The image was taken on June 9, 2013 and features ancient Bristlecone pines in the foreground, with the arch of the Milky Way visible in the sky:

Ancient Bristlecone pines with an even more ancient Milky Way in the background. Credit and copyright: Ken Brandon.

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

June 14, 2013December 23, 2015 by Jason Major

Details of Yuri Gagarin’s Tragic Death Revealed

Yuri Gagarin on the way to his historic Vostok launch on April 12, 1961. Image: NASA

On the morning of April 12, 1961, Soviet cosmonaut Yuri Gagarin lifted off aboard Vostok 1 to become the first human in space, spending 108 minutes in orbit before landing via parachute in the Saratov region of the USSR. The soft-spoken and well-mannered Gagarin, just 27 years old at the time, became an instant hero, representing the success of the Soviet space program (Alan Shepard’s shorter, suborbital flight happened less than a month later) to the entire world. Gagarin later went on to become a director for the Cosmonaut Training Center and was preparing for a second space flight. Tragically, he was killed when a MiG-15 aircraft he was piloting crashed on March 27, 1968.

Gagarin’s death has long been shrouded by confusion and controversy, with many theories proposed as to the actual cause. Now, 45 years later, details about what really happened to cause the death of the first man in space have come out — from the first man to go out on a spacewalk, no less.

Televised image of Aleksey Leonov during his spacewalk outside Vokshod 2

According to an article published online today on Russia Today (RT.com) former cosmonaut Aleksey Leonov — who performed the first EVA on March 18, 1965 — has revealed details about the accident that killed both Yuri Gagarin and his flight instructor Vladimir Seryogin in March 1968.

Officially the cause of the crash was said to be the ill-fated result of an attempt to avoid a foreign object during flight training in their MiG-15UTI, a two-seated, dual-controlled training version of the widely-produced Soviet aircraft. “Foreign objects” could be anything, from balloons to flocks of birds to airborne debris to… well, you see where one could go with that. (And over the years many have.)

The maneuver led to the aircraft going into a tailspin and crashing, killing both men. But experienced pilots like Gagarin and Seryogin shouldn’t have lost control of their plane like that — not according to Leonov, who has been trying to release details of the event for the past 20 years… if only that the pilots’ families might know the truth.

A Sukhoi Su-15 fighter jet (Wikipedia Commons)

Now, a declassified report, which Leonov has been permitted to share, shows what actually happened during the training flight: an “unauthorized Su-15 fighter” flew too close to Gagarin’s MiG, disrupting its flight and sending it into a spin.

“In this case, the pilot didn’t follow the book, descending to an altitude of 450 meters,” Leonov says in the RT.com article. “While afterburning the aircraft reduced its echelon at a distance of 10-15 meters in the clouds, passing close to Gagarin, turning his plane and thus sending it into a tailspin — a deep spiral, to be precise — at a speed of 750 kilometers per hour.”

The pilot of the Su-15 — who is still alive — was was not named, a condition of Leonov’s permission to share the information.

According to first woman in space Valentina Tereshkova, who was officially grounded by the government after Gagarin’s death to avoid a loss of another prominent cosmonaut, the details come as a bittersweet relief.

“The only regret here is that it took so long for the truth to be revealed,” Tereshkova said. “But we can finally rest easy.”

Read the full story here on RT.com.

Tereshkova and Leonov at the Cosmonautics Museum in Moscow during a ceremony in 2011 celebrating the 50th anniversary of the launch of Yuri Gagarin. (NASA photo.)

June 14, 2013December 23, 2015 by Nancy Atkinson

Get Ready for the ATV-4 Docking with this Fun Music Video

The view when ATV-3 approached the ISS in 2012. Credit: NASA.

Recall how during a space shuttle mission, the astronauts were awoken each day with music radioed up from Mission Control? Now, ESA has started a tradition of creating a music video to celebrate various events, such as the docking of their Automated Transfer Vehicle. The ATV-4, named Albert Einstein, will dock with the International Space Station on Saturday, June 15 at 13:46 UTC (9:46 a.m. EDT, and here’s a little hip hop to get you in the mood.

ESA teamed up with hip hop group Ugly Duckling for a super space remix of the song “Elevation.”

The connection to the group and this ATV mission was perfect, as the long-time DJ for Ugly Duckling goes under the stage name DJ Young Einstein. ESA liked the group because they are known for their ‘old-school’ hip-hop with an upbeat message and non-violent lyrics.

TATV-4 is ferrying a record cargo of 6.6 tons to the ISS – food, fuel, water, oxygen, science experiments and undisclosed special treats for the six-member crew on the space station.

You can see other music videos from ESA here.

June 14, 2013December 23, 2015 by Elizabeth Howell

NASA’s Sci-Fi Vision: Robots Could Help Humanity Mine Asteroids

An artist's conception of a spacecraft designed to pick up an asteroid. Credit: NASA/Advanced Concepts Laboratory

In a few generations of robotics, we’ll see mighty machines able to fully construct themselves and operate from the surface of asteroids — providing applications for mining, NASA researchers say in a new study.

The scientists are convinced that this type of research is not only possible, but also able to support itself financially. (Costs overruns are a notorious factor in space exploration as it pushes frontiers both literally and engineering-wise.)

“Advances in robotics and additive manufacturing have become game-changing for the prospects of space industry. It has become feasible to bootstrap a self-sustaining, self-expanding industry at reasonably low cost,” the researchers stated in a new study.

A couple of factors are pointing to this, researchers said: private industry is willing and able to get involved. Advances in technologies such as 3-D printing are making off-world work more feasible. Also, humanity’s surveys of space resources has revealed the elements needed to make rubber, plastic and alloys needed for machinery.

NASA proposes a robotic flotilla could mine nearby space rocks. They caution the technology won’t be ready tomorrow, and more surveys will need to be done of nearby asteroids to figure out where to go next. There is, however, enough progress to see building blocks, the agency stated.

An artist's conception of a space exploration vehicle approaching an asteroid. Credit: NASA — An artist’s conception of a space exploration vehicle approaching an asteroid. Credit: NASA

“Robots and machines would just make the metal and propellants for starters,” stated Phil Metzger, a senior research physicist at NASA’s Kennedy Space Center, who led the study.

“The first generation of robots makes the second generation of hardware, except the comparatively lightweight electronics and motors that have to be sent up from Earth. It doesn’t matter how much the large structures weigh because you didn’t have to launch it.”

A computer model in the study showed that in six generations of robotics, these machines will be able to construct themselves and operate without any need of materials from Earth.

Artist impression of the Arkyd Interceptor, a low cost asteroid mission that enables accelerated exploration. Credit: Planetary Resources.

At least two startups would agree with the optimism: Deep Space Industries and Planetary Resources.

In the past year, members of both firms have proposed asteroid mining ideas, and since then, Planetary Resources has also unveiled other projects such as a public space telescope (perhaps in a bid to diversify revenues and attract more attention.)

In early 2013, when NASA submitted its fiscal budget request for 2014, it also got in on the hubbub: the agency proposed robotically venturing out to an asteroid and bringing it back to Earth.

That’s received many questions from critics (including at least one government space committee), but NASA has argued it is feasible and a way to unite innovation across various sectors.

“Because asteroids are loaded with minerals that are rare on Earth, near-Earth asteroids and the asteroid belt could become the mining centers for remotely-operated excavators and processing machinery,” NASA stated.

“In the future, an industry could develop to send refined materials, rare metals and even free, clean energy to Earth from asteroids and other bodies.”

Check out more details of the new report in the Journal of Aerospace Engineering.

A side note, this isn’t the only NASA-funded group looking at asteroid mining. In September, NASA’s Innovative Advanced Concepts office offered Phase 1 funding to a Robotic Asteroid Prospector proposal.

Source: NASA

June 14, 2013December 23, 2015 by Ken Kremer

Curiosity Gets Set for Epic Drive after Laser Blasting Mars Watery Secrets

Curiosity’s hi tech ‘hand’ and percussion drill hovers above 2nd bore hole at Cumberland mudstone rock after penetrating laser blasting to unlock secrets of ancient flow of Martian water. Photo mosaic assembled from high resolution Mastcam images on May 21, 2013, Sol 281. Credit: NASA/JPL-Caltech/MSSS/Ken Kremer (kenkremer.com)/Marco Di Lorenzo

Ten months after her breathtaking touchdown on the Red Planet, NASA’s Curiosity rover is nearly set to embark on an epic drive like no other in space history to the slopes of mysterious Mount Sharp – looming supreme inside Gale Crater and the primary mission objective.

But not before the robot completes a few last critical science tasks to more fully illuminate the potential for the origin of Martian microbes in the habitable zone discovered at the work-site of her first penetrations into Mars water altered surface.

The rover science team has chosen a trio of final targets to investigate around the shallow basin of Yellowknife Bay, that resembles a dried out lakebed, where Curiosity has toiled for the past six months, drilled twice into the mudstone outcrops at ‘John Klein’ and ‘Cumberland’ and repeatedly fired her powerful science laser.

Curiosity will revisit a pair of intriguing outcrops named ‘Point Lake’ and ‘Shaler’ that the rover briefly investigated before arriving at ‘John Klein’, said Joy Crisp of JPL, Curiosity’s deputy project scientist, at a media briefing.

“Shaler might be a river deposit. Point Lake might be volcanic or sedimentary. A closer look at them could give us better understanding of how the rocks we sampled with the drill fit into the history of how the environment changed.”

Curiosity will employ nearly all her science instruments to study the outcrops – except the drill.

“It’s highly unlikely to drill at ‘Point Lake’ and ‘Shaler’ because we want to get driving,” Crisp told Universe Today.

“We might drill somewhere along the way to Mount Sharp depending on whether we find something compelling.”

'Point Lake' Outcrop in Gale Crater. A priority target for a closer look byCuriosity before the rover departs the "Glenelg" area east of its landing site. The pitted outcrop called "Point Lake" is about 7 feet (2 meters) wide and 20 inches (50 centimeters) high. A closer inspection may yield information about whether it is a volcanic or sedimentary deposit. Credit: NASA/JPL-Caltech/MSSS — ‘Point Lake’ Outcrop in Gale Crater. A priority target for a closer look byCuriosity before the rover departs the “Glenelg” area east of its landing site. The pitted outcrop called “Point Lake” is about 7 feet (2 meters) wide and 20 inches (50 centimeters) high. A closer inspection may yield information about whether it is a volcanic or sedimentary deposit. Credit: NASA/JPL-Caltech/MSSS

Researchers will also use the DAN (Dynamic Albedo of Neutrons) instrument to look for traces of mineral bound water – in the form of hydrogen – at the boundary between bedrock areas of mudstone and sandstone.

Thereafter, Curiosity’s handlers will command the 1 ton behemoth to begin the drive to the lower reaches of Mount Sharp which lies about 6 miles (10 kilometers) distant – as the Martian crow flies.

Mount Sharp rises about 3.4 miles (5.5 km) from the center of Gale Crater. It’s taller than Mount Ranier in Washington State.

Billions of years of Mars geologic history are preserved in the sedimentary layers of Mount Sharp – along with potential signatures of the chemical ingredients of life.

Curiosity Route Map From 'Glenelg' to Mount Sharp. This map shows where NASA's Mars rover Curiosity landed in August 2012 at "Bradbury Landing"; the area where the rover worked from November 2012 through May 2013 at and near the "John Klein" target rock in the "Glenelg" area; and the mission's next major destination, the entry point to the base of Mount Sharp. Credit: NASA/JPL-Caltech/Univ. of Arizona — Curiosity Route Map From ‘Glenelg’ to Mount Sharp.
This map shows where NASA’s Mars rover Curiosity landed in August 2012 at “Bradbury Landing”; the area where the rover worked from November 2012 through May 2013 at and near the “John Klein” target rock in the “Glenelg” area; and the mission’s next major destination, the entry point to the base of Mount Sharp. Credit: NASA/JPL-Caltech/Univ. of Arizona

“The drive will start in a few weeks,” said Curiosity Project Manager Jim Erickson of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. at the briefing.

But the team will be on the lookout for targets of opportunity along the way.

“We are on a mission of exploration. If we come across scientifically interesting areas, we are going to stop and examine them before continuing the journey,” Erikson added.

“If we pass something amazing and compelling we might turn around and drive back,” Crisp added.

It could take nearly a year to arrive at Mount Sharp. And Curiosity must pass through a potentially treacherous dune field to get there – see NASA JPL route map above.

“We are looking for the best path though,” said Erickson.

NASA chose Gale as the landing site specifically to dispatch Curiosity to investigate the sedimentary layers of Mount Sharp because it exhibited signatures of clay minerals that form in neutral water and that could possibly support the origin and evolution of simple Martian life forms, past or present.

“We have a real desire to get to Mount Sharp because there we see variations in the mineralogy as we go up from the base to higher levels and a change in the record of the environment,” said Crisp.

Analysis of the initial gray colored, powdery ‘John Klein’ sample by Curiosity’s pair of onboard chemistry labs – SAM & Chemin – revealed that this location on Mars was habitable in the past and possesses the key chemical ingredients – such as clay minerals – required to support microbial life forms- thereby successfully accomplishing the key science objective of the mission and making a historic discovery long before even arriving at destination Mount Sharp.

Besides the science measurements, researchers also learned lot about how to operate the complex drilling and sample delivery mechanisms much more efficiently for the second drilled rock sample.

The sieved and pulverized Cumberland sample was delivered in about a quarter of the time compared to the John Klein sample – accomplished at a deliberately measured and cautious pace.

Context view of Curiosity’s 2nd drill site at Cumberland rock on the floor of Yellowknife Bay basin of ancient water altered rocks where the rover found environmental conditions favorable for microbial life. Mastcam images on May 23, 2013, Sol 283. Credit: NASA/JPL-Caltech/MSSS/Ken Kremer (kenkremer.com)/Marco Di Lorenzo — Context view of Curiosity’s 2nd drill site at Cumberland rock on the floor of Yellowknife Bay basin showing ancient water altered rocks where the rover found environmental conditions favorable for microbial life. Mastcam images on May 23, 2013, Sol 283. Credit: NASA/JPL-Caltech/MSSS/Ken Kremer (kenkremer.com)/Marco Di Lorenzo

Analysis of the “Cumberland” powder is currently in progress. The goal is to determine how it compares chemically and to confirm the results found at ‘John Klein.’

“No results from Cumberland are available yet,” said Crisp.

The robot used the powerful million watt ChemCam laser to blast into the Cumberland drill hole and gray tailings scattered on the surface to glean as much insight and measurements of the chemical composition and transformation by water as possible before departing.

Curiosity has just arrived at “Point Lake’. Stay tuned for my next Curiosity story.

Meanwhile, Curiosity’s older sister rover Opportunity has likewise discovered clay minerals and a habitable zone on the opposite side of the Red Planet – details here.

And don’t forget to “Send Your Name to Mars” aboard NASA’s MAVEN orbiter- details here. Deadline: July 1, 2013

Ken Kremer

…………….

Learn more about Mars, Curiosity, Opportunity, MAVEN, LADEE and NASA missions at Ken’s upcoming lecture presentations

June 23: “Send your Name to Mars on MAVEN” and “CIBER Astro Sat, LADEE Lunar & Antares Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA, 8 PM

This time lapse mosaic shows Curiosity moving her robotic arm to drill into her 2nd rockt target named “Cumberland” to collect powdery material on May 19, 2013 (Sol 279) for analysis by her onboard chemistry labs; SAM & Chemin. The photomosaic was stitched from raw images captured by the navcam cameras on May 14 & May 19 (Sols 274 & 279). Credit: NASA/JPL-Caltech/Ken Kremer/Marco Di Lorenzo

June 14, 2013October 18, 2016 by Fraser Cain

Closest Star to the Sun

This is a classic trick question. Ask a friend, “what is the closest star?” and then watch as they try to recall some nearby stars. Sirius maybe? Alpha something or other? Betelgeuse?

The answer, obviously, is the Sun; that massive ball of plasma located a mere 150 million km from Earth.

Let’s be more precise; what’s the closest star to the Sun?

Closest Star

You might have heard that it’s Alpha Centauri, the third brightest star in the sky, just 4.37 light-years from Earth.

But Alpha Centauri isn’t one star, it’s a system of three stars. First, there’s a binary pair, orbiting a common center of gravity every 80 years. Alpha Centauri A is just a little more massive and brighter than the Sun, and Alpha Centauri B is slightly less massive than the Sun. Then there’s a third member of this system, the faint red dwarf star, Proxima Centauri.

It’s the closest star to our Sun, located just a short 4.24 light-years away.

Closest Star, Proxima Centauri — Proxima Centauri

Alpha Centauri is located in the Centaurus constellation, which is only visible in the Southern Hemisphere. Unfortunately, even if you can see the system, you can’t see Proxima Centauri. It’s so dim, you need a need a reasonably powerful telescope to resolve it.

Let’s get sense of scale for just how far away Proxima Centauri really is. Think about the distance from the Earth to Pluto. NASA’s New Horizons spacecraft travels at nearly 60,000 km/h, the fastest a spacecraft has ever traveled in the Solar System. It will have taken more than nine years to make this journey when it arrives in 2015. Travelling at this speed, to get to Proxima Centauri, it would take New Horizons 78,000 years.

Proxima Centauri has been the nearest star for about 32,000 years, and it will hold this record for another 33,000 years. It will make its closest approach to the Sun in about 26,700 years, getting to within 3.11 light-years of Earth. After 33,000 years from now, the nearest star will be Ross 248.

What About the Northern Hemisphere?

Bernard's Star, one of the closest stars to the Sun — Bernard’s Star

For those of us in the Northern Hemisphere, the closest visible star is Barnard’s Star, another red dwarf in the constellation Ophiuchus. Unfortunately, just like Proxima Centauri, it’s too dim to see with the unaided eye.

The closest star that you can see with the naked eye in the Northern Hemisphere is Sirius, the Dog Star. Sirius, has twice the mass and is almost twice the size of the Sun, and it’s the brightest star in the sky. Located 8.6 light-years away in the constellation Canis Major – it’s very familiar as the bright star chasing Orion across the night sky in Winter.

How do Astronomers Measure the Distance to Stars?

They use a technique called parallax. Do a little experiment here. Hold one of your arms out at length and put your thumb up so that it’s beside some distant reference object. Now take turns opening and closing each eye. Notice how your thumb seems to jump back and forth as you switch eyes? That’s the parallax method.

To measure the distance to stars, you measure the angle to a star when the Earth is one side of its orbit; say in the summer. Then you wait 6 month, until the Earth has moved to the opposite side of its orbit, and then measure the angle to the star compared to some distant reference object. If the star is close, the angle will be measurable, and the distance can be calculated.

You can only really measure the distance to the nearest stars this way, since it only works to about 100 light-years.

The 20 Closest Stars

Here is a list of the 20 closest star systems and their distance in light-years. Some of these have multiple stars, but they’re part of the same system.

Alpha Centauri – 4.2
Barnard’s Star – 5.9
Wolf 359 – 7.8
Lalande 21185 – 8.3
Sirius – 8.6
Luyten 726-8 – 8.7
Ross 154 – 9.7
Ross 248 – 10.3
Epsilon Eridani – 10.5
Lacaille 9352 – 10.7
Ross 128 – 10.9
EZ Aquarii – 11.3
Procyon – 11.4
61 Cygni – 11.4
Struve 2398 – 11.5
Groombridge 34 – 11.6
Epison Indi – 11.8
Dx Carncri – 11.8
Tau Ceti – 11.9
GJ 106 – 11.9

According to NASA data, there are 45 stars within 17 light years of the Sun. There are thought to be as many as 200 billion stars in our galaxy. Some are so faint that they are nearly impossible to detect. Maybe, with technological improvements, scientists will find even closer stars.

June 13, 2013December 23, 2015 by Jason Major

Navy Researchers Put Dark Lightning to the SWORD

Dark lightning occurs within thunderstorms and flings gamma rays and antimatter into space. (Science@NASA video)

Discovered “by accident” by NASA’s Fermi Gamma-ray Space Telescope in 2010, dark lightning is a surprisingly powerful — yet invisible — by-product of thunderstorms in Earth’s atmosphere. Like regular lightning, dark lightning is the result of a natural process of charged particles within storm clouds trying to cancel out opposing charges. Unlike normal lightning, though, dark lightning is invisible to our eyes and doesn’t radiate heat or light — instead, it releases bursts of gamma radiation.

What’s more, these gamma-ray outbursts originate at relatively low altitudes well within the storm clouds themselves. This means that airplane pilots and passengers flying through thunderstorms may be getting exposed to gamma rays from dark lightning, which are energetic enough to pass through the hull of an aircraft… as well as anything or anyone inside it. To find out how such exposure to dark lightning could affect air travelers, the U.S. Naval Research Laboratory (NRL) is conducting computer modeling tests using their SoftWare for the Optimization of Radiation Detectors — SWORD, for short.

Terrestrial Gamma-ray Flashes (TGFs) are extremely intense, sub-millisecond bursts of gamma rays and particle beams of matter and anti-matter. First identified in 1994, they are associated with strong thunderstorms and lightning, although scientists do not fully understand the details of the relationship to lightning. The latest theoretical models of TGFs suggest that the particle accelerator that creates the gamma rays is located deep within the atmosphere, at altitudes between six and ten miles, inside thunderclouds and within reach of civilian and military aircraft.

These models also suggest that the particle beams are intense enough to distort and collapse the electric field within thunderstorms and may, therefore, play an important role in regulating the production of visible lightning. Unlike visible lightning, TGF beams are sufficiently broad — perhaps about half a mile wide at the top of the thunderstorm — that they do not create a hot plasma channel and optical flash; hence the name, “dark lightning.”

A team of NRL Space Science Division researchers, led by Dr. J. Eric Grove of the High Energy Space Environment (HESE) Branch, is studying the radiation environment in the vicinity of thunderstorms and dark lightning flashes. Using the Calorimeter built by NRL on NASA’s Fermi Gamma-ray Space Telescope they are measuring the energy content of dark lightning and, for the first time, using gamma rays to geolocate the flashes.

As a next step, Dr. Chul Gwon of the HESE Branch is using NRL’s SoftWare for the Optimization of Radiation Detectors (SWORD) to create the first-ever simulations of a dark lightning flash striking a Boeing 737. He can calculate the radiation dosage to the passengers and crew from these Monte Carlo simulations. Previous estimates have indicated it could be as high as the equivalent of hundreds of chest X-rays, depending on the intensity of the flash and the distance to the source.

Simulation of a Boeing 737 struck by dark lightning. Green tracks show the paths of gamma rays from the dark flash as they enter the aircraft from below. (Credit: U.S. Naval Research Laboratory) — Simulation of a Boeing 737 struck by dark lightning. Green tracks show the paths of gamma rays from the dark flash as they enter the aircraft from below.
(Credit: U.S. Naval Research Laboratory)

SWORD simulations allow researchers to study in detail the effects of variation in intensity, spectrum, and geometry of the flash. Dr. Grover’s team is now assembling detectors that will be flown on balloons and specialized aircraft into thunderstorms to measure the gamma ray flux in situ. The first balloon flights are scheduled to take place this summer.

Source: NRL News

June 13, 2013December 23, 2015 by Elizabeth Howell

Should This Alien World Even Exist? This Young Disk Could Challenge Planet-Formation Theories

An image of TW Hydrae and the protoplanetary stuff surrounding the star. Astronomers believe a planet is forming within the gas and dust and sweeping up debris, as shown by the gap in this picture. Credit: NASA, ESA, J. Debes (STScI), H. Jang-Condell (University of Wyoming), A. Weinberger (Carnegie Institution of Washington), A. Roberge (Goddard Space Flight Center), and G. Schneider (University of Arizona/Steward Observatory)

Take a close look at the blurry image above. See that gap in the cloud? That could be a planet being born some 176 light-years away from Earth. It’s a small planet, only 6 to 28 times Earth’s mass.

That’s not even the best part.

This alien world, if we can confirm it, shouldn’t be there according to conventional planet-forming theory.

The gap in the image above — taken by the Hubble Space Telescope — probably arose when a planet under construction swept through the dust and debris in its orbit, astronomers said.

That’s not much of a surprise (at first blush) given what we think we know about planet formation. You start with a cloud of debris and gas swirling around a star, then gradually the bits and pieces start colliding, sticking together and growing bigger into small rocks, bigger ones and eventually, planets or gas giant planet cores.

But there’s something puzzling astronomers this time around: this planet is a heck of a long way from its star, TW Hydrae, about twice Pluto’s distance from the sun. Given that alien systems’ age, that world shouldn’t have formed so quickly.

An illustration of TW Hydrae's disk in comparison with that of Earth's solar system. Credit: NASA, ESA, and A. Feild (STScI) — An illustration of TW Hydrae’s disk in comparison with that of Earth’s solar system. Credit: NASA, ESA, and A. Feild (STScI)

Astronomers believe that Jupiter took about 10 million years to form at its distance away from the sun. This planet near TW Hydrae should take 200 times longer to form because the alien world is moving slower, and has less debris to pick up.

But something must be off, because TW Hydrae‘s system is believed to be only 8 million years old.

“There has not been enough time for a planet to grow through the slow accumulation of smaller debris. Complicating the story further is that TW Hydrae is only 55 percent as massive as our sun,” NASA stated, adding it’s the first time we’ve seen a gap so far away from a low-mass star.

The lead researcher put it even more bluntly: “Typically, you need pebbles before you can have a planet. So, if there is a planet and there is no dust larger than a grain of sand farther out, that would be a huge challenge to traditional planet formation models,” stated John Debes, an astronomer at the Space Telescope Science Institute in Baltimore.

Protoplanet Hypothesis — Like a raindrop forming in a cloud, a star forms in a diffuse gas cloud in deep space. As the star grows, its gravitational pull draws in dust and gas from the surrounding molecular cloud to form a swirling disk called a “protoplanetary disk.” This disk eventually further consolidates to form planets, moons, asteroids and comets. Credit: NASA/JPL-Caltech

At this point, you would suppose the astronomers are seriously investigating other theories. One alternative brought up in the press release: perhaps part of the disc collapsed due to gravitational instability. If that is the case, a planet could come to be in only a few thousand years, instead of several million.

“If we can actually confirm that there’s a planet there, we can connect its characteristics to measurements of the gap properties,” Debes stated. “That might add to planet formation theories as to how you can actually form a planet very far out.”

A rare double transit of Jupiter's moon Ganymede (top) and Io on Jan. 3, 2013. Here, the sun is shining from the left causing shadows cast by the moons to fall onto the planet's cloud tops. Credit: Damian Peach — A rare double transit of Jupiter’s moon Ganymede (top) and Io on Jan. 3, 2013. Here, the sun is shining from the left causing shadows cast by the moons to fall onto the planet’s cloud tops. Credit: Damian Peach

There’s a trick with the “direct collapse” theory, though: astronomers believe it takes a bunch of matter that is one to two times more massive than Jupiter before a collapse can occur to form a planet.

Recall that this world is no more than 28 times the mass of Earth, as best as we can figure. Well, Jupiter itself is 318 times more massive than Earth.

There are also intriguing results about the gap. Chile’s Atacama Large Millimeter/submillimeter Array (ALMA) — which is designed to look at dusty regions around young stars — found that the dust grains in this system, orbiting nearby the gap, are still smaller than the size of a grain of sand.

Astronomers plan to use ALMA and the James Webb Space Telescope, which should launch in 2018, to get a better look. In the meantime, the results will be published in the June 14 edition of the Astrophysical Journal.

Source: HubbleSite