Posted on by Elizabeth Howell

How NASA’s Next Mars Spacecraft Will Greet The Red Planet On Sunday

An artist concept of MAVEN in orbit around Mars. (Credit: NASA's Goddard Spaceflight Center).

NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) orbiter is oh-so-close to its destination after a 10-month journey. It’s scheduled to arrive in orbit Sunday (Sept. 21) around 9:50 p.m. EDT (1:50 a.m. UTC) if all goes well, but there are a few things that need to happen, in order, first.

One big obstacle is already out of the way. MAVEN controllers had expected to do final engine burn tweaks to put it on the right trajectory, but the mission is so on-target that it won’t be needed.

“#MAVEN orbit insertion sequence has been activated on the s/c. No additional ground intervention is needed to enter #Mars’ orbit on Sunday,” the official account tweeted yesterday (Sept. 18).

So what does the sequence entail? MAVEN will need to turn on its six thruster engines for a 33-minute braking maneuver to slow it down. This will allow the gravity of Mars to “capture” the spacecraft into an elliptical or oval-shaped orbit.

Should that all go safely, MAVEN still has a lot of work to do before being ready to capture information about the upper atmosphere of the Red Planet. All spacecraft go through a commissioning phase to ensure their instruments are working correctly and that they are in the correct orbit and orientation to do observations.

As such, controllers will spend about six weeks moving MAVEN into a more circular orbit and testing out its instruments. Usually this period is done without interruption, but NASA wants to capture information when Comet Siding Spring comes whizzing by Mars Oct. 19.

Controllers are interested in learning about the comet and its effect on the upper atmosphere, so they will stop the commissioning to make those measurements. MAVEN will also be oriented in such a way that its solar panels are protected as much as possible from the dust, although scientists now believe the risk of strikes is very low.

This graphic depicts the orbit of comet C/2013 A1 Siding Spring as it swings around the sun in 2014. On Oct. 19, 2014 the comet will have a very close pass at Mars. Its nucleus will miss Mars by about 82,000 miles (132,000 kilometers). Credit: NASA/JPL-Caltech
This graphic depicts the orbit of comet C/2013 A1 Siding Spring as it swings around the sun in 2014. On Oct. 19, 2014 the comet will have a very close pass at Mars. Its nucleus will miss Mars by about 82,000 miles (132,000 kilometers). Credit: NASA/JPL-Caltech

MAVEN is expected to work at Mars for a year, but investigators are hoping it will be for longer so that the atmosphere can be tracked through more of a solar cycle. The Sun’s activity is a major influencer on the atmosphere and the “stripping” of molecules from it over time, which could have thinned Mars’ atmosphere in the ancient past.

The spacecraft will also serve as a backup communications and data relay for the Opportunity and Curiosity rovers on the surface, which might be needed if some of the older NASA Mars spacecraft that fulfill that function experience technical difficulties.

Posted on by Shannon Hall

219 Million Stars Create the Most Detailed Catalogue of our Milky Way Yet

A density map of part of the Milky Way disk, constructed from IPHAS data. The axes show galactic latitude and longitude, coordinates that relate to the position of the centre of the galaxy. The mapped data are the counts of stars detected in i, the longer (redder) wavelength broad band of the survey, down to a faint limit of 19th magnitude. Although this is just a small section of the full map, it portrays in exquisite detail the complex patterns of obscuration due to interstellar dust. Credit: Hywel Farnhill, University of Hertfordshire.

On the darkest of nights, thousands of stars are sprinkled across the celestial sphere above us. Or, to be exact, there are 9,096 stars observable across the entire sky. Divide that number in half, and there are 4,548 stars (give or take a few) visible from horizon to horizon.

But this number excludes the glowing band stretching across the night sky, the Milky Way. It’s the disk of our own galaxy, a system stretching 100,000 light-years across. The naked eye is unable to distinguish individual specks of light, but the Isaac Newton Telescope (INT) on La Palma in the Canary Islands has recently charted 219 million separate stars in this disk alone.

For the last 10 years a team of astronomers led by Geert Barentsen from the University of Hertfordshire has been collecting and compiling light from all stars brighter than 20th magnitude, or one million times fainter than the human eye can see (at 6th magnitude).

They created a beautiful density map of the Milky Way, giving them new insight into the structure of this vast system. The black, fog-like regions are galactic dust, which blocks more distant light. The brighter regions are densely packed stars.

The INT took measurements in two broad filters, which captured light at the red end of the visible spectrum, and in one narrow filter, which captured light only from the hydrogen emission line, H-alpha. The inclusion of H-alpha enables exquisite mapping of nebulae, glowing clouds of hydrogen gas.

The production of the catalogue is an example of modern astronomy’s exploitation of “big data.” But it would also grace the walls of any art studio.

Posted on by Nancy Atkinson

Stunning Photo Alert! Winners Announced for “Astronomy Photographer of the Year” Competition

Aurora over a Glacier Lagoon. Credit and copyright: James Woodend, UK

The winners of the 2014 “Astronomy Photographer of the Year” competition have been announced at the Royal Observatory in Greenwich England, and British photographer James Woodend’s gorgeous image of the aurora dancing across the Icelandic night sky was named the overall winner. This is the sixth year for the competition, which is run by the ROG and the Sky at Night Magazine.

“Every year the competition becomes more and more challenging to judge and we’re always astounded by the skill of the photographers,” said Dr. Maggie Aderin-Pocock, a presenter on The Sky at Night and one of the judges for the competition. “The Deep Space category, where the entrants have been able to capture such amazing details of objects light-years away and are almost on par with images taken by the Hubble Space Telescope, never fails to impress.”

See more gorgeous images and a list of the winners in the various categories below:

Earth and Space

James Woodend (UK) with Aurora over a Glacier Lagoon (Winner and Overall Winner)
Matt James (Australia) with Wind Farm Star Trails (Runner-up)
Patrick Cullis (USA) with Moon Balloon (Highly Commended)
Catalin Beldea (Romania) with Totality from Above the Clouds (Highly Commended)
O Chul Kwon (South Korea) with Venus-Lunar Occultation (Highly Commended)

Horsehead Nebula (IC 434). Credit and copyright: Bill Snyder, USA.
Horsehead Nebula (IC 434). Credit and copyright: Bill Snyder, USA.

Deep Space

Bill Snyder (USA) with Horsehead Nebula (IC 434) (Winner)
David Fitz-Henry (Australia) with The Helix Nebula (NGC 7293) (Runner-Up)
J.P Metsävainio (Finland) with Veil Nebula Detail (IC 1340) (Highly Commended)
Rogelio Bernal Andreo (USA) with California vs Pleiades (Highly Commended)
Marco Lorenzi (China) with At the Feet of Orion (NGC 1999) – Full Field (Highly Commended)

Stunning closeup of our Sun, entitled 'Ripples in a Pond.' Credit and copyright: Alexandra Hart, UK
Stunning closeup of our Sun, entitled ‘Ripples in a Pond.’ Credit and copyright: Alexandra Hart, UK

Our Solar System

Alexandra Hart (UK) with Ripples in a Pond (Winner)
George Tarsoudis (Greece) with Best of the Craters (Runner-Up)
Alexandra Hart (UK) with Solar Nexus (Highly Commended)
Stephen Ramsden (USA) with Calcium K Eruption (Highly Commended)
Tunç Tezel (Turkey) with Diamond and Rubies (Highly Commended)

The Horsehead Nebula (IC 434). Credit and copyright: Shishir and Shashank Dholakia, USA, Aged 15.
The Horsehead Nebula (IC 434). Credit and copyright: Shishir and Shashank Dholakia, USA, Aged 15.

Young Astronomy Photographer of the Year

Shishir & Shashank Dholakia (USA, aged 15) with The Horsehead Nebula (IC 434) (Winner)
Emmett Sparling (Canada, aged 15) with New Year over Cypress Mountain (Runner-up)
Olivia Williamson (UK, aged 10) with The Martian Territory (Highly Commended)
Shishir & Shashank Dholakia (USA, aged 15) with The Heart Nebula (IC 1805) (Highly Commended)
Emily Jeremy (UK, aged 12) with Moon Behind the Trees (Highly Commended)

Hybrid Solar Eclipse. Credit and copyright: Eugen Kamenew, Germany
Hybrid Solar Eclipse. Credit and copyright: Eugen Kamenew, Germany

Special Prize: People and Space

Eugen Kamenew (Germany) with Hybrid Solar Eclipse 2 (Winner)
Julie Fletcher (Australia) with Lost Souls (Runner-up)

Coastal Stairways. Credit and copyright: Chris Murphy, New Zealand
Coastal Stairways. Credit and copyright: Chris Murphy, New Zealand

Special Prize: Sir Patrick Moore prize for Best Newcomer

Chris Murphy (New Zealand) with Coastal Stairways (Winner)

NGC 3718 via a robotic scope, Credit and copyright: Mark Hanson, USA
NGC 3718 via a robotic scope, Credit and copyright: Mark Hanson, USA

Robotic Scope Image of the Year

Mark Hanson (USA) with NGC 3718 (Winner)

For all the winners see the ROG website, and for other photos not shown here, you can see more at the Astronomy Photographer of the Year Flickr site . If you are in the UK, you can see an exhibition of the winning photos as the Astronomy Centre, Royal Observatory, Greenwich, from now until February 22, 2015.

Find more info at the ROG website, where you can also find info about the competition for next year — start planning ahead!

Posted on by Elizabeth Howell

Look Up! The Space Station Must Be The Ultimate Stargazing Location

"I never imagined that flying to space would give me a different view of our entire galaxy," tweeted Expedition 41 astronaut Alexander Gerst from the International Space Station in September 2014. Credit: Alexander Gerst / Twitter

While NASA often speaks about the power of Earth observation from the International Space Station, the picture above from one of the astronauts on board now shows something else — you can get an awesome view of the Milky Way.

With the view unobscured by the atmosphere, the picture from Expedition 41 European astronaut Alexander Gerst shows that his perch on the ISS is pretty amazing. We wonder how it compares to some of the desert or mountaintop observatories here on Earth! And there are astronomical experiments on board, such as this one that may have found dark matter.

Below we’ve handpicked some of the best recent pictures from Gerst and NASA astronaut Reid Wiseman, a crewmate, as they take in the wonder of our planet and the universe.

Posted on by Shannon Hall

This Exoplanet Has Prematurely Aged its Star

An exoplanet about ten times Jupiter's mass located some 330 light years from Earth. X-ray: NASA/CXC/SAO/I.Pillitteri et al; Optical: DSS; Illustration: NASA/CXC/M.Weiss

Hot young stars are wildly active, emitting huge eruptions of charged particles form their surfaces. But as they age they naturally become less active, their X-ray emission weakens and their rotation slows.

Astronomers have theorized that a hot Jupiter — a sizzling gas giant circling close to its host star — might be able to sustain a young star’s activity, ultimately prolonging its youth. Earlier this year, two astronomers from the Harvard-Smithsonian Center for Astrophysics tested this hypothesis and found it true.

But now, observations of a different system show the opposite effect: a planet that’s causing its star to age much more quickly.

The planet, WASP-18b has a mass roughly 10 times Jupiter’s and circles its host star in less than 23 hours. So it’s not exactly a classic hot Jupiter — a sizzling gas giant whipping around its host star — because it’s characteristics are a little more drastic.

“WASP-18b is an extreme exoplanet,” said lead author Ignazio Pillitteri of the National Institute for Astrophysics in Italy, in a news release. “It is one of the most massive hot Jupiters known and one of the closest to its host star, and these characteristics lead to unexpected behavior.”

The team thinks WASP-18 is 600 million years old, relatively young compared to our 5-billion-year-old Sun. But when Pillitteri and colleagues took a long look with NASA’s Chandra X-ray Observatory at the star, they didn’t see any X-rays — a telltale sign the star is youthful. In fact, the observations show the star is 100 times less active than it should be.

“We think the planet is aging the star by wreaking havoc on its innards,” said co-author Scott Wolk (who also worked on the previous study showing the opposite effect) from the Harvard-Smithsonian Center for Astrophysics.

The researchers argue that tidal forces created by the gravitational pull of the massive planet might have disrupted the star’s magnetic field generated by the motion of conductive plasma deep inside the star. It’s possible the exoplanet significantly interfered with the upper layers of the convective zone, reduced any mixing of stellar material, and effectively canceled out the magnetic activity.

The effect of tidal forces from the planet may also explain an unusually high amount of lithium seen in the star. Lithium is usually abundant in younger stars, but disappears over time as convection carries it further toward the star’s center, where it’s destroyed by nuclear reactions. So if there’s less convection — as seems to be the case for WASP 18 — then the lithium won’t circulate toward the center of the star and instead will survive.

The findings have been published in the July issue of Astronomy and Astrophysics and are available online.

Posted on by Elizabeth Howell

Sandy Ridges Pose A Mystery For Future Martian Beach Vacations

A September 2014 image from the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter showing transverse aeolian ridges. Credit: NASA/JPL/University of Arizona

What are these thick dune-like features on Mars, and how were they formed? Scientists are still trying to puzzle out these ridges, which you can see above in a more tropical region of the Red Planet called Iapygia, which is south of Syrtis Major. The thick ridges were captured from orbit by the Mars Reconnaissance Orbiter’s High Resolution Imaging Science Experiment (HiRISE), and we’ve included some more intriguing pictures below the jump.

“Called transverse aeolian ridges, or TARs, the features stand up to 6 meters tall and are spaced a few tens of meters apart. They are typically oriented transverse to modern day wind directions, and often found in channels and crater interiors,” read an update on the University of Arizona’s HiRISE blog.

“The physical process that produces these features is still mysterious. Most TARs display no evidence of internal structure, so it is difficult to discern exactly how they were formed.”

A wider view of the Iapygia region on Mars, where transverse aeolian ridges (TARs) -- dune-like features -- were spotted in 2014. PIcture taken by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona
A wider view of the Iapygia region on Mars, where transverse aeolian ridges (TARs) — dune-like features — were spotted in 2014. PIcture taken by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona

This picture from the NASA spacecraft was taken in Iapygia, which is south of Syrtis Major. While scientists say these look similar to TARs in other parts of the Red Planet, the features have layers on the northwest faces and a paucity on the southern side.

Scientists suggest it’s because these TARs may have had wedge-shaped layers, which hints that they would have gotten taller as material was added to the ridges. They hope to do further studies to learn more about how TARs formed in other regions on Mars.

We’ve included other recent releases from the HiRISE catalog below, so enjoy the Martian vistas!

An image of Eridania Basin, a southern region of Mars that once could been a lake or inland sea. Picture taken by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona
An image of Eridania Basin, a southern region of Mars that once could been a lake or inland sea. Picture taken by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona
Scientists are still puzzling out the nature and formation of these light-toned deposits in the old Vinogradov Crater on Mars. Picture taken by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona
Scientists are still puzzling out the nature and formation of these light-toned deposits in the old Vinogradov Crater on Mars. Picture taken by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona
Older lava flows in Daedalia Planum on Mars. Picture taken by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona
Older lava flows in Daedalia Planum on Mars. Picture taken by the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter. Credit: NASA/JPL/University of Arizona
Posted on by Elizabeth Howell

Saturn-Circling Cassini Spacecraft Plumbs Titan’s Seas Next Week

Titan's thick haze. Image: NASA/JPL/Space Science Institute.

Is the surf up yet on Titan? As the moon of Saturn moves towards northern summer, scientists are trying to spot signs of the winds picking up. This weekend, the Cassini spacecraft plans a look at the the largest body of liquid on Titan, Kraken Mare, to see if there are any waves on this huge hydrocarbon sea.

Cassini will make the 105th flyby of Titan on Monday (Sept. 22) to probe the moon’s atmosphere, seas and even a crater. The spacecraft will examine “the seas and lakes of the northern polar area, including Kraken and Ligeia at resolution better than 3 miles (5 kilometers) per pixel,” the Cassini website stated.

Besides wet areas of Titan, Cassini will also look at dunes and the relatively fresh-looking Sinlap crater, where scientists hope to get a high-resolution image. Managers also plan a mosaic of Tsegihi — a bright zone south of the equator — and the darker dune-filled area of Fensal. The spacecraft additionally will examine aerosols and the transparency of hazes in Titan’s atmosphere.

Titan is of interest to scientists in part because its chemistry is a possible precursor to what made life possible. Earlier this week, Cassini transmitted several raw images of its view of Titan and Saturn right now — some of the latest pictures are below.

A raw image of Saturn's moon Titan taken by the Cassini spacecraft Sept. 14, 2014. Credit: NASA/JPL/Space Science Institute
A raw image of Saturn’s moon Titan taken by the Cassini spacecraft Sept. 14, 2014. Credit: NASA/JPL/Space Science Institute
Atmospheric features on Saturn's moon Titan appear to be faintly visible in this raw image taken by the Cassini spacecraft Sept. 10, 2014. Credit: NASA/JPL/Space Science Institute
Atmospheric features on Saturn’s moon Titan appear to be faintly visible in this raw image taken by the Cassini spacecraft Sept. 10, 2014. Credit: NASA/JPL/Space Science Institute
A crescent Titan beckons the Cassini spacecraft (in Saturn's system) in this image taken Aug. 24, 2014. Credit: NASA/JPL/Space Science Institute
A crescent Titan beckons the Cassini spacecraft (in Saturn’s system) in this image taken Aug. 24, 2014. Credit: NASA/JPL/Space Science Institute
A raw image of Saturn taken by the Cassini spacecraft Sept. 15, 2014. Credit: NASA/JPL/Space Science Institute
A raw image of Saturn taken by the Cassini spacecraft Sept. 15, 2014. Credit: NASA/JPL/Space Science Institute
Posted on by Ken Kremer

Completely Clandestine CLIO Climbs through Clouds to Orbit on Mystery Mission

United Launch Alliance (ULA) Atlas V rocket carrying the CLIO mission for Lockheed Martin Space Systems Company launched at 8:10 p.m. EDT September 16, 2014 from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer - kenkremer.com

CAPE CANAVERAL AIR FORCE STATION, FL – On a gloomy night and delayed by rain showers and thick threatening clouds to the very last moment of a two and a half launch window, the completely clandestine satellite known only as CLIO climbed slowly from a Cape Canaveral launch pad atop the thunderous flames of an Atlas V rocket on Tuesday evening on a mysterious mission to orbit.

Under a veil of secrecy for an unknown US government customer, the clouds cleared just enough to finally launch CLIO on a United Launch Alliance (ULA) Atlas V booster at 8:10 p.m. EDT September 16, 2014 from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla.

A series of ugly thunderstorms with a deluge of rain shows repeatedly passed by the launch pad forcing a weather related delay from the initial daylight launch time of 5:44 p.m.

The 19 story rocket is protected by a quartet of lighting masts ringing the launch pad. And they did their job last night.

Mysterious CLIO payload shrouded beneath 4-meter-diameter payload fairing in this up close view of the top of the United Launch Alliance (ULA) Atlas V rocket prior to launch from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer - kenkremer.com
Mysterious CLIO payload shrouded beneath 4-meter-diameter payload fairing in this up close view of the top of the United Launch Alliance (ULA) Atlas V rocket prior to launch from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer – kenkremer.com

It was touch and go with the weather at the Cape all evening. None of us knew what would happen with the satellite we know nothing about. So the weather induced hazy view of the pad fit perfectly with the mystery missions hazy motif.

Normally, even the highly secretive US National Reconnaissance Office (NRO) claims ownership of their satellites named with what seems to be a random numbering scheme.

But not for CLIO. The only publicly released information is that CLIO was built by Lockheed Martin and derived from their commercial A2100 series satellite bus used for commercial telecommunications satellites among others.

“It is an honor to work with Lockheed Martin Space Systems Company and all of our mission partners to launch this very important satellite,” said Jim Sponnick, ULA vice president, Atlas and Delta Programs, in a statement.

United Launch Alliance (ULA) Atlas V rocket carrying the CLIO mission for Lockheed Martin Space Systems Company launched at 8:10 p.m. EDT September 16, 2014 from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer - kenkremer.com
United Launch Alliance (ULA) Atlas V rocket carrying the CLIO mission for Lockheed Martin Space Systems Company launched at 8:10 p.m. EDT September 16, 2014 from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer – kenkremer.com

“Today’s launch marks ULA’s 11th successful mission this year and the 88th successful mission since ULA was formed in December 2006, a true testament to the team’s focus on mission success, one launch at a time.”

Myself and other media were allowed to visit the launch pad and photograph the rocket up close with the CLIO insignia emblazoned on the payload fairing, shrouding the mysterious satellite beneath.

But even the CLIO insignia is completely nondescript, unlike the rather artistic NRO logos with cool imaginary creatures and a number like NR0-66 for example.

We do know the type of rocket utilized is an Atlas V 401 configuration vehicle, which includes a 4-meter-diameter payload fairing and no solid rocket motors.

Mysterious CLIO and Atlas V rocket prior to launch from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer - kenkremer.com
Mysterious CLIO and Atlas V rocket prior to launch from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer – kenkremer.com

We do know that the Atlas booster for this mission was powered by a Russian made RD AMROSS RD-180 engine as is customary. The Centaur upper stage was powered by a single Aerojet Rocketdyne RL10A engine, according to ULA.

We do know the launch was successful and certainly a spectacular sight for myself and all the spectators.

Nightfall over CLIO and Atlas V rocket at Space Launch Complex-41 prior to weather delayed Sept. 16, 2014 launch from Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer - kenkremer.com
Nightfall over CLIO and Atlas V rocket at Space Launch Complex-41 prior to weather delayed Sept. 16, 2014 launch from Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer – kenkremer.com

CLIO is presumably somewhere in Earth orbit, circling overhead secretly at unknown altitude(s) and inclination(s).

CLIO marks ULA’s 60th successful mission from Cape Canaveral, the 11th successful mission this year and the 88th successful mission since the company’s formation in 2006.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

Extended time exposure partial streak shot of CLIO launch on September 16, 2014 from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer - kenkremer.com
Extended time exposure partial streak shot of CLIO launch on September 16, 2014 from Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer – kenkremer.com
Photographers including Ken Kremer/Universe Today set up cameras to capture up close imagery of Sept. 16, 2014 launch of mysterious CLIO satellite and Atlas V rocket at Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer - kenkremer.com
Photographers including Ken Kremer/Universe Today set up cameras to capture up close imagery of Sept. 16, 2014 launch of mysterious CLIO satellite and Atlas V rocket at Space Launch Complex-41 on Cape Canaveral Air Force Station, Fla. Credit: Ken Kremer – kenkremer.com
Posted on by Elizabeth Howell

Radiation Blast Delays NASA Spacecraft’s Arrival At Dwarf Planet Ceres

Artist's conception of the NASA Dawn spacecraft approaching Ceres. Credit: NASA

NASA’s Dawn spacecraft experienced technical problems in the past week that will force it to arrive at dwarf planet Ceres one month later than planned, the agency said in a statement yesterday (Sept. 16).

Controllers discovered Dawn was in safe mode Sept. 11 after radiation disabled its ion engine, which uses electrical fields to “push” the spacecraft along. The radiation stopped all engine thrusting activities. The thrusting resumed Monday (Sept. 15) after controllers identified and fixed the problem, but then they found another anomaly troubling the spacecraft.

Dawn’s main antenna was also disabled, forcing the spacecraft to send signals to Earth (a 53-minute roundtrip by light speed) through a weaker secondary antenna and slowing communications. The cause of this problem hasn’t been figured out yet, but controllers suspect radiation affected the computer’s software. A computer reset has solved the issue, NASA added. The spacecraft is now functioning normally.

Vesta (left) and Ceres. Vesta was photographed up close by the Dawn spacecraft from July 2011-Sept. 2012, while the best views we have to date of Ceres come from the Hubble Space Telescope. The bright white spot is still a mystery. Credit: NASA
Vesta (left) and Ceres. Vesta was photographed up close by the Dawn spacecraft from July 2011-Sept. 2012, while the best views we have to date of Ceres come from the Hubble Space Telescope. The bright white spot is still a mystery. Credit: NASA

“As a result of the change in the thrust plan, Dawn will enter into orbit around dwarf planet Ceres in April 2015, about a month later than previously planned. The plans for exploring Ceres once the spacecraft is in orbit, however, are not affected,” NASA’s Jet Propulsion Laboratory stated in a press release.

Dawn is en route to Ceres after orbiting the huge asteroid Vesta between July 2011 and September 2012. A similar suspected radiation blast three years ago also disabled Dawn’s engine before it reached Vesta, but the ion system worked perfectly in moving Dawn away from Vesta when that phase of its mission was complete, NASA noted.

Among Dawn’s findings at Vesta is that the asteroid is full of hydrogen, and it contains the hydrated mineral hydroxyl. This likely came to the asteroid when smaller space rocks brought the volatiles to its surface through low-speed collisions.

Spacecraft can experience radiation through energy from the Sun (particularly from solar flares) and also from cosmic rays, which are electrically charged particles that originate outside the Solar System. Earth’s atmosphere shields the surface from most space-based radiation.

Source: Jet Propulsion Laboratory

Posted on by Nancy Atkinson

Giveaway: Win a Copy of “Astrophotography” by Thierry Legault

'Astrophotography' by Thierry Legault, now in English. Image courtesy Rocky Nook.

A newly published English version of the book, “Astrophotography” by Thierry Legault provides detailed, step-by-step instructions of how to start or improve your photography of astronomical objects. But this is not just a dry manual: Legault tells stories and explains details in a manner that seems like he is talking directly to you, and he shares the expertise he has garnered from over 20 years of amateur astrophotography.

You can read our full review of the book here.

Universe Today is proud to announce we have several copies of this engaging book to give away, and two ways to win.

NOTE: This giveaway is now closed. Thanks for everyone’s participation!

The first way to win a copy is our usual “giveaway” process where we have two copies available to winners. In order to be entered into the giveaway drawing, just put your email address into the box at the bottom of this post (where it says “Enter the Giveaway”) before Monday, September 22, 2014. We’ll send you a confirmation email, so you’ll need to click that to be entered into the drawing. If you’ve entered our giveaways before you should also receive an email with a link on how to enter.

The second way to win is through Facebook. Again, two copies are available through this avenue. Please see our Facebook post for this giveaway, then we ask you to “like” the Rocky Nook Publishing Facebook page. Your “like” to Rocky Nook will be considered an entry to the contest. From there, a winner will be chosen and the winners will be notified through Facebook.

The publisher has specified that for this contest, winners chosen from the US will be sent a copy of the book, while winners chosen from other countries will receive an ebook.

Continue reading “Giveaway: Win a Copy of “Astrophotography” by Thierry Legault”