Sunday, October 19, 2014

Cat 4 Hurricane Gonzalo Threatens Bermuda and Delays Antares Launch to Space Station

Cat 4 Hurricane Gonzalo Threatens Bermuda and Delays Antares Launch to Space Station:

NOAA's GOES-East satellite captured this image of Hurricane Gonzalo off the U.S. East Coast on Oct. 16 at 13:07 UTC (9:07 a.m. EDT). Gonzalo is classified as Category 4 storm. Credit: NASA/NOAA GOES Project


NOAA’s GOES-East satellite captured this image of Hurricane Gonzalo off the U.S. East Coast on Oct. 16 at 13:07 UTC (9:07 a.m. EDT). Gonzalo is classified as Category 4 storm and has caused a delay to the next Antares rocket launch. Credit: NASA/NOAA GOES Project
Hurricane Gonzalo, the first major Atlantic Ocean basin hurricane in three years, has strengthened to a dangerous Category 4 storm, threatening Bermuda and forcing a postponement of the upcoming launch of the Orbital Sciences Antares rocket to the space station from the Virginia shore to no earlier than Oct. 27.

A hurricane warning is in effect for the entire island of Bermuda.

NASA and Orbital Sciences had no choice but to delay the Antares blastoff from Oct. 24 to no earlier than Oct. 27 because Bermuda is home to an “essential tracking site” that must be operational to ensure public safety in case of a launch emergency situation.

Antares had been slated for an early evening liftoff with the Cygnus cargo carrier on the Orb-3 mission to the International Space Station (ISS).

NASA and Orbital issued the following statement:

“Due to the impending arrival of Hurricane Gonzalo on the island of Bermuda, where an essential tracking site used to ensure public safety during Antares launches is located, the previously announced “no earlier than” (NET) launch date of October 24 for the Orb-3 CRS mission to the International Space Station for NASA is no longer feasible.”

Orbital Sciences Corporation Antares rocket and Cygnus spacecraft prior to blast off on July 13 2014 from Launch Pad 0A at NASA Wallops Flight Facility , VA, on the Orb-2 mission bound for the International Space Station. Credit: Ken Kremer - kenkremer.com


Orbital Sciences Corporation Antares rocket and Cygnus spacecraft prior to blast off on July 13 2014 from Launch Pad 0A at NASA Wallops Flight Facility , VA, on the Orb-2 mission bound for the International Space Station. Credit: Ken Kremer – kenkremer.com
The powerful Gonzalo is currently expected to make a direct hit on Bermuda on Friday afternoon, Oct. 17. It’s packing devastating maximum sustained winds exceeding 145 mph (225 kph).

NASA and NOAA satellites including the Terra, Aqua and GOES-East satellites are providing continuous coverage of Hurricane Gonzalo as it moves toward Bermuda, according to a NASA update today.

The ISS-RapidScat payload tracking ocean winds, that was just attached to the exterior of the ISS, is also designed to help with hurricane monitoring and forecasting.

Tropical storm force winds and 20 to 30 foot wave heights are expected to impact Bermuda throughout Friday and continue through Saturday and into Sunday.

“The National Hurricane Center expects hurricane-force winds, and rainfall totals of 3 to 6 inches in Bermuda. A storm surge with coastal flooding can be expected in Bermuda, with large and destructive waves along the coast. In addition, life-threatening surf and riptide conditions are likely in the Virgin Islands, Puerto Rico, Dominican Republic, Bahamas. Those dangerous conditions are expected along the U.S. East Coast and Bermuda today, Oct. 16,” according to NASA.

On Oct. 15 at 15:30 UTC (11:30 a.m. EDT) NASA's Terra satellite captured this image of Hurricane Gonzalo in the Atlantic Ocean. Credit: NASA Goddard MODIS Rapid Response Team


On Oct. 15 at 15:30 UTC (11:30 a.m. EDT) NASA’s Terra satellite captured this image of Hurricane Gonzalo in the Atlantic Ocean. Credit: NASA Goddard MODIS Rapid Response Team
After the hurricane passes, a team will be sent to assess the impact of the storm on Bermuda and the tracking station. Further delays are possible if Bermuda’s essential infrastructure systems are damaged, such as power, transportation and communications.

The Antares/Cygnus rocket and cargo ship launch from the Mid-Atlantic Regional Spaceport at NASA’s Wallops Flight Facility along the eastrn shore of Virginia.

Liftoff is currently target for October 27 at 6:44 p.m. (EDT). The rendezvous and berthing of Cygnus with the ISS remains on November 2, with grapple of the spacecraft by the station’s robotic arm at approximately 4:58 a.m. (EST), according to a NASA update.

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

Ken Kremer

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‘Death Star’ Ocean? Seven Moons That Could Host Huge Hidden Liquid Reservoirs

‘Death Star’ Ocean? Seven Moons That Could Host Huge Hidden Liquid Reservoirs:

A view of Mimas from the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute


A view of Mimas from the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute
Could there be an ocean hidden somewhere in that Death Star-like picture? This is an image of Mimas, a moon of Saturn, and just yesterday (Oct. 15) newly released data from the Cassini spacecraft suggests there are big liquid reservoirs underneath its surface.

“The amount of the to-and-fro motion indicates that Mimas’ interior is not uniform. These wobbles can be produced if the moon contains a weirdly shaped, rocky core or if a sub-surface ocean exists beneath its icy shell,” said Cornell University in a press release. More flybys with the Cassini spacecraft will be required to learn more about what lies beneath.

You can read more about the study (led by Cornell astronomy research associate Radwan Tajeddine) in Science, where it was published. Below, learn more about other worlds in the Solar System that could host oceans under their surface.

Enceladus

Recent Cassini images of Saturn's moon Enceladus backlit by the sun show the fountain-like sources of the fine spray of material that towers over the south polar region. This image was taken looking more or less broadside at the "tiger stripe" fractures observed in earlier Enceladus images. It shows discrete plumes of a variety of apparent sizes above the limb (edge) of the moon. This image was acquired on Nov. 27, 2005. Image Credit: NASA/JPL/Space Science Institute


Cassini images of Saturn’s moon Enceladus backlit by the sun show the fountain-like sources of the fine spray of material that towers over the south polar region. This image was taken looking more or less broadside at the “tiger stripe” fractures observed in earlier Enceladus images. It shows discrete plumes of a variety of apparent sizes above the limb (edge) of the moon. This image was acquired on Nov. 27, 2005. Image Credit: NASA/JPL/Space Science Institute
After nearly a decade of speculation, this year the Cassini spacecraft returned gravity data suggesting Enceladus (another moon of Saturn) does have a large subsurface ocean near its south pole, if not a global ocean. If confirmed, that could help explain why scientists see water gushing out of fractures in that area. As this recent paper by Cassini scientists shows, Enceladus is a promising location for habitability.

Titan

A halo of light surrounds Saturn's moon Titan in this backlit picture, showing its atmosphere. Credit: NASA/JPL/Space Science Institute


A halo of light surrounds Saturn’s moon Titan in this backlit picture, showing its atmosphere. Credit: NASA/JPL/Space Science Institute
By the way, anyone noticed that we still haven’t even left Saturn’s system? Titan is usually high on astrobiology wish lists for researchers because its hydrocarbon chemistry could be precursors to how life evolved. What’s not talked about as much, though, is at least two research findings pointing to evidence of a hidden ocean. Evidence comes from Titan’s tidal flexing from interacting with Saturn — which is 10 times more than what would be expected with a solid core — and the way that it moves on its own axis as well as around Saturn.

Europa

Rendering showing the location and size of water vapor plumes coming from Europa's south pole. Credit: NASA/ESA/L. Roth/SWRI/University of Cologne


Rendering showing the location and size of water vapor plumes coming from Europa’s south pole. Credit: NASA/ESA/L. Roth/SWRI/University of Cologne
That Minecraft-looking object floating beside Europa there is a rendering showing where water vapor erupted from the Jovian moon, spotted by the Hubble Space Telescope in 2013. We were lucky enough to have a close-up view of Europa in the 1990s and early 2000s courtesy of NASA’s Galileo spacecraft. What we know for sure is there’s thick ice on Europa. What’s underneath is not known, but there’s long been speculation that it could be a subsurface ocean that may have more water than our own planet.

Io

Jupiter's volcanic moon Io , imaged by the Galileo spacecraft in 1997. Credit: NASA/JPL/University of Arizona


Jupiter’s volcanic moon Io , imaged by the Galileo spacecraft in 1997. Credit: NASA/JPL/University of Arizona
Still flying around Jupiter here, we now turn our attention to Io — a place that is often remarked upon because of its blotchy appearance as well as all of the volcanoes on its surface. A newer analysis of Galileo data in 2011 — looking at some of the lesser-understood magnetic field data signatures — led one research team to conclude there could be a magma ocean lurking underneath that violence.

Triton

A glimpse of Triton from the Voyager 2 spacecraft, which flew by the Neptunian moon in August 1989. Credit: NASA/JPL


A glimpse of Triton from the Voyager 2 spacecraft, which flew by the Neptunian moon in August 1989. Credit: NASA/JPL
Little is known about Triton because only one spacecraft whizzed by it — Voyager 2, which took a running pass through the Neptune system in August 1989. An Icarus paper two years ago speculated that the world could host a subsurface ocean, but more data is needed. The energy of Neptune (which captured Triton long ago) could have melted its interior through tidal heating, possibly creating water from the ice in its crust.

Charon

Hubble image of Pluto and some of its moons, Charon, Nix and Hydra. Image Credit: NASA, ESA, H. Weaver (JHU/APL), A. Stern (SwRI), and the HST Pluto Companion Search Team


Hubble image of Pluto and some of its moons, Charon, Nix and Hydra. Image Credit: NASA, ESA, H. Weaver (JHU/APL), A. Stern (SwRI), and the HST Pluto Companion Search Team
We don’t have any close-up pictures of this moon of Pluto yet, but just wait a year. The New Horizons spacecraft will zoom past Charon and the rest of the system in July 2015. In the meantime, however, findings based on a model came out this summer in Icarus suggesting Charon — despite being so far from the Sun — might have had a subsurface ocean in the past. Or even now. The key is its once eccentric orbit, which would have produced tidal heating while interacting with Pluto. The science team plans to look for cracks that could be indicative of “the structure of the moon’s interior and how easily it deforms, and how its orbit evolved,” stated Alyssa Rhoden of NASA’s Goddard Space Flight Center in Maryland, who led the research.

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Solar ‘Bombs’ And Mini-Tornadoes Spotted By Sun-Watching Spacecraft

Solar ‘Bombs’ And Mini-Tornadoes Spotted By Sun-Watching Spacecraft:

An image of a May 9, 2014 coronal mass ejection from the Sun using data from both the Interface Region Imaging Spectrograph (IRIS) spacecraft and the Solar Dynamics Observatory. Credit: NASA, Lockheed Martin Solar & Astrophysics Laboratory


An image of a May 9, 2014 coronal mass ejection from the Sun using data from both the Interface Region Imaging Spectrograph (IRIS) spacecraft and the Solar Dynamics Observatory. Credit: NASA, Lockheed Martin Solar & Astrophysics Laboratory
My, the Sun is a violent place. I mean, we knew that already, but there’s even more evidence for that using new data from a brand-new NASA spacecraft. There’s talk now about tornadoes and jets and even “bombs” swirling amid our Sun’s gassy environment.

A huge set of results from NASA’s Interface Region Imaging Spectrograph (IRIS) spacecraft reveals the true nature of a mysterious transition zone between Sun’s surface and the corona, or atmosphere. Besides the pretty fireworks and videos, these phenomena are telling scientists more about how the Sun moves energy from the center to the outskirts. And, it could tell us more about how stars work in general.

The results are published in five papers yesterday (Oct. 15) in Science magazine. Below, a brief glimpse of what each of these papers revealed about our closest star.

Bombs



This is a heck of a lot of energy packed in here. Raging at temperatures of 200,000 degrees Fahrenheit (111,093 degrees Celsius) are heat “pockets” — also called “bombs” because they release energy quickly. They were found lower in the atmosphere than expected. The paper is here (led by Hardi Peter of the Max Planck Institute for Solar System Research in Gottingen, Germany.)

Tornadoes



It’s a twist! You can see some structures in the chromosphere, just above the Sun’s surface, showing gas spinning like a tornado. They spin around as fast as 12 miles (19 kilometers) a second, which is considered slow-moving on the Sun. The paper is here (led by Bart De Pontieu, the IRIS science lead at Lockheed Martin in California).

High-speed jets

Artist's impression of the solar wind from the sun (left) interacting with Earth's magnetosphere (right). Credit: NASA

Artist’s impression of the solar wind from the sun (left) interacting with Earth’s magnetosphere (right). Credit: NASA
How does the solar wind — that constant stream of charged particles that sometimes cause aurora on Earth — come to be? IRIS spotted high-speed jets of material moving faster than ever observed, 90 miles (145 kilometers) a second. Since these jets are emerging in spots where the magnetic field is weaker (called coronal holes), scientists suspect this could be a source of the solar wind since the particles are thought to originate from there. The paper is here (led by Hui Tian at the Harvard-Smithsonian Center for Astrophysics in Massachusetts.)

Nanoflares

A solar filament erupts with a coronal mass ejection in this image captured by NASA's Solar Dynamics Observatory in August 2012. Credit: NASA's GSFC, SDO AIA Team


A solar filament erupts with a coronal mass ejection in this image captured by NASA’s Solar Dynamics Observatory in August 2012. Credit: NASA’s GSFC, SDO AIA Team
Those solar flares the Sun throws off happen when magnetic field lines cross and then snap back into place, flinging particles into space. Nanoflares could do the same thing to heat up the corona, and that’s something else that IRIS is examining. The paper is here (led by Paola Testa, at the Harvard-Smithsonian Center for Astrophysics.)

Structures and more



And here is the transition region in glorious high-definition. Improving on data from the Skylab space station in the 1970s (bottom of video), you can see all sorts of mini-structures on the Sun. The more we learn about these 2,000-mile (3,220-km) objects, the better we’ll understand how heating moves through the Sun. The paper is here (led by Viggo Hansteen, at the University of Oslo in Norway.)

Source: NASA

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Balloon launcher Zero2Infinity Sets Its Sights to the Stars

Balloon launcher Zero2Infinity Sets Its Sights to the Stars:

Zero2Infinity announced on October 15, their plans to begin micro-satellite launches to low-earth orbit by 2017. (Credit: OIIOO)


Zero2Infinity announced on October 15, their plans to begin micro-satellite launches to low-earth orbit by 2017. (Illustration Credits: OIIOO)
Clearly, the sky is not the limit for balloon launcher Zero2Infinity. Based in Barcelona, Spain, the company announced this week their plans to launch payloads to orbit using a balloon launch system. The Rockoon is a portmanteau, as Lewis Carroll would have said: the blend of the words rocket and balloon.

The launch system announced by the company is called Bloostar. The Rockoon system begins with a balloon launch to stratospheric altitudes followed by the igniting of a 3 stage rocket to achieve orbit. The Rockoon concept is not new. Dr. James Van Allen with support from the US Navy developed and launched the first Rockoons in 1949. Those were just sounding rockets, Bloostar will take payloads to low-earth orbit and potentially beyond.

The Zero2Infinity Bloostar launch vehicle. Three stages will use a set of liquid fuel engines clustered as concentric toroids. (Photo Credit: 0II00)


The Zero2Infinity Bloostar launch vehicle. Three stages will use a set of liquid fuel engines clustered as concentric toroids. (Photo Credit: 0II00)
The advantage of rocket launch from a balloon is that it takes the Earth’s atmosphere out as a factor in design and as a impediment to reaching orbit. The first phase of the Bloostar system takes out 99% of the Earth’s atmosphere by reaching an altitude of over 20 km (>65,000 feet). Aerodynamics is not a factor so the stages are built out rather than up. The stages of the Bloostar design are a set of concentric rings which are sequentially expended as it ascends to orbit.

Zero2Infinity is developing a liquid fuel engine that they emphasize is environmentally friendly. The first stage firing of Bloostar will last 160 seconds, reach 250 km of altitude and an inertial speed of 3.7 km/s. This is about half the velocity necessary for reach a stable low earth orbit. The second stage will fire for 230 seconds and achieve an altitude of 530 km with velocity of 5.4 km/s. The 3rd and final stage motor will fire at least twice with a coast period to achieve the final orbit. Zero2Infinity states that their Bloostar system will be capable of placing a 75kg (165 lbs) payload into a 600 km (372 mi) sun-synchronous orbit. In contrast, the International Space Station orbits at 420 km (260 mi) altitude.

The Bloostar launch phases. Zero2Infinity intends to de-orbit the final stage to minimize their contribution to the growing debris field in low-earth orbit. Their plans are to launch from a ship at sea. (Photo Credit: 0II00)


The Bloostar launch phases. Zero2Infinity intends to de-orbit the final stage to minimize their contribution to the growing debris field in low-earth orbit. Their plans are to launch from a ship at sea. (Photo Credit: 0II00)
For the developing cubesat space industry, a 75 kg payload to orbit is huge. A single cubesat 10x10x10 cm (1U) will typically weigh about 1 kg so Bloostar would be capable of launching literally a constellation of cubesats or in the other extreme, a single micro-satellite with potentially its own propulsion system to go beyond low-earth orbit.

The Rockoon concept is not unlike what Scaled Composites undertakes with a plane and rocket. Their Whiteknight planes lift the SpaceShips to 50,000 feet for takeoff whereas the Zero2Infinity balloon will loft Bloostar to 65,000 feet or higher. The increased altitude of the balloon launch reduces the atmospheric density to half of what it is at 50,000 feet and altogether about 8% of the density at sea level.

The act of building and launching a stratospheric balloon to 30 km (100,000 feet) altitude with >100 kg instrument payloads is a considerable accomplishment. This is just not the releasing of a balloon but involves plenty of logistics and telecommunications with instrumentation and also the returning of payloads safely to Earth. This is clearly half of what is necessary to reach orbit.

Bloostar is blazing new ground in Spain. The ground tests of their liquid fuel rocket engine are the first of its kinds in the country. Zero2Infinity began launching balloons in 2009. The founder and CEO, Jose Mariano Lopez-Urdiales is an aeronautical engineer educated in Spain with R&D experience involving ESA, MIT and Boeing. He has speerheaded organizations and activities in his native Spain. In 2002 he presented to the World Space Congress in Houston, the paper “The Role of Balloons in the Future Development of Space Tourism”.

References:

Zero2Infinity Press Release

Bloostar Launch Cycle

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Here’s a Look at Comet Siding Spring Two Days Before its Encounter with Mars

Here’s a Look at Comet Siding Spring Two Days Before its Encounter with Mars:

by Nancy Atkinson on October 17, 2014
Comet 2013 A1 Siding Spring on October 17, 2014, with two days to go until its Martian encounter. Very dense Milkyway starfield in the background with many darker obscured regions. Credit and copyright: Damian Peach/SEN.


Comet 2013 A1 Siding Spring on October 17, 2014, with two days to go until its Martian encounter. Very dense Milkyway starfield in the background with many darker obscured regions. Credit and copyright: Damian Peach/SEN.
The excitement continues to build as Comet Siding Spring rapidly approaches the Red Planet, and here’s the latest view of the comet from prolific astrophotographer Damian Peach. While Comet Siding Spring’s encounter with Mars on October 19 will not be visible from Earth with the unaided eye, skywatchers in mid-northern latitudes, can now view the comet; an 8-inch (20 cm) or larger telescopes is needed to follow the comet as it travels from Scorpius north to Ophiuchus and its encounter with Mars on October 19.

The comet will come within 139,500 km (86,000 miles) above the planet’s surface on Sunday.

In Depth: How to See Comet Siding Spring as it Encounters Mars

Below, see a really nice animation put together by Kevin Gill of the path the comet will take past Mars.

An animation of the approach of the comet C/2013 A1 Siding Spring on Mars over the next few days. Credit: Kevin Gill.


An animation of the approach of the comet C/2013 A1 Siding Spring on Mars over the next few days. Credit: Kevin Gill.
Kevin said on G+ that his animation is based on vector ephemeris from the JPL Horizons system.

As our David Dickinson discussed earlier this week, if you were an astronaut stranded on the surface of Mars, the comet’s passage would be a spectacular sight under the dark Martian sky. Some scientists suggest it could even spawn a short but brilliant meteor shower caused by cometary dust grains plunging into the Martian atmosphere.

The spacecraft in orbit around Mars will be watching Comet Siding Spring too. The fleet of spacecraft from ESA, NASA and ISRO will hide behind the Red Planet on Sunday morning, trying to avoid possible bombardment by tiny grains of dust from the comet. But before and after that, the spacecraft will attempt to gather data on the comet as well as try to measure how the gas and dust interact with the Martian atmosphere.

Stay tuned for news on the comet’s encounter with Mars.
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Watch Live as Comet Siding Spring Flys By Mars

Watch Live as Comet Siding Spring Flys By Mars:

by Nancy Atkinson on October 19, 2014
Not only will the Mars orbiters gather information about the comet and its dust before, during and after the encounter, a fleet of additional telescopes will make the most of the rare opportunity. Credit: NASA.


Not only will the Mars orbiters gather information about the comet and its dust before, during and after the encounter, a fleet of additional telescopes will make the most of the rare opportunity. Credit: NASA.
Comet Siding Spring will pass close to Mars today, Sunday, October 19, at 18:32 UTC. The comet will come within 139,500 km (87,000 miles) of the Red Planet, which is sixteen times closer to Mars than any known comet has ever come to Earth. About 100 minutes after the closest approach, the densest part of the comet’s tail will pass Mars’ location. You can watch live below courtesy of Slooh, ESA and the Virtual Telescope, below:

Slooh will feature two shows. The first show, billed “Close Call – Comet Siding Spring Zips by Mars,” will start at 11:15 AM PDT / 2:15 PM EDT / 18:15 UTC – International times here where Slooh will track Comet Siding Spring on close-approach live from South Africa and later from the Canary Islands. The second show, billed “Comet Siding Spring – the Outcome” will start at 5:30 PM PDT / 8:30 PM EDT / 00:30 UTC (10/20) – International times here – where Slooh will continue to track the comet live from Slooh’s southern observatory located at the Catholic University (PUC) – both shows will feature expert commentary by esteemed astrobiologist David Grinspoon and Slooh host Geoff Fox. The latter show will feature a special discussion with Slooh astronomer Bob Berman, who will be on location in Chile. Viewers can ask questions during each show by using hashtag #SloohComet.

Here’s ESA’s livestream:

Also, Gianluca Masi’s Virtual Telescope: streaming begins Sunday, Oct. 19 at 11:45 a.m. CDT (16:45 UT)
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A Compendium of Universe Today Comet Siding Spring Articles: January 2013 – October 2014

A Compendium of Universe Today Comet Siding Spring Articles: January 2013 – October 2014:

Comet C/2013 A1 Siding Spring passed between the Small Magellanic Cloud (left) and the rich globular cluster NGC 130 on August 29, 2014. Credit: Rolando Ligustri


Comet C/2013 A1 Siding Spring passed between the Small Magellanic Cloud (left) and the rich globular cluster NGC 130 on August 29, 2014. Credit: Rolando Ligustri
We present here a compendium of Universe Today articles on comet Siding Spring. Altogether 18 Universe Today stories and counting have represented our on-going coverage of a once in a lifetime event. The articles beginning in February 2013, just days after its discovery, lead to the comet’s penultimate event – the flyby of Mars, October 19, 2014. While comet Siding Spring will reach perihelion just 6 days later, October 25, 2014, it will hardly have sensed the true power and impact that our Sun can have on a comet.

Siding Spring’s Oort Cloud cousin, Comet ISON in November 2013 encountered the Sun at a mere 1.86 million km. The intensity of the Sun’s glare was 12,600 times greater than what Siding Spring will experience in a few days. Comet ISON did not survive its passage around the Sun but Comet Siding Spring will soon turn back and begin a very long journey to its place of origin, the Oort Cloud far beyond Pluto.

An animation of comet Siding Springs passage through the inner Solar System. The scale size of its place of origin would dwarf the orbits of the Solar System to little more than a small dot. (Illustration Credit: Near-Earth Object (NEO) office, NASA/JPL)


An animation of comet Siding Springs passage through the inner Solar System. The scale size of its place of origin would dwarf the orbits of the Solar System to little more than a small dot. (Illustration Credit: Near-Earth Object (NEO) office, NASA/JPL)
The closest approach for comet Siding Spring with the Sun – perihelion is at a distance of 1.39875 Astronomical Units (1 AU being the distance between the Earth and Sun), still 209 million km (130 million miles). The exact period of the comet is not exactly known but it is measured in millions of years. In my childhood astronomy book, it stated that comet Halley, when it is at its furthest distance from the Sun, is moving no faster than a galloping horse. This has also been all that comet Siding Spring could muster for millions of years – the slightest of movement in the direction of the Sun.

It is only in the last 3 years, out all the millions spent on its journey, that it has felt the heat of the Sun and been in proximity to the  planetary bodies of our Solar System. This is story of all long period comets. A video camera on Siding Spring would have recorded the emergence and evolution of one primate out of several, one that left the trees to stand on two legs, whose brain grew in size and complexity and has achieved all the technological wonders (and horrors) we know of today.

Now with its close encounter with Mars, the planet’s gravity will bend the trajectory of the comet and reduce its orbital period to approximately one million years. No one will be waiting up late for its next return to the inner Solar System.



It is also unknown what force in the depths of the Oort cloud nudged the comet into its encounter with Mars and the Sun. Like the millions of other Oort cloud objects, Siding Spring has spent its existence – 4.5 Billion years, in the darkness of deep space, with its parent star, the Sun, nothing more than a point of light, the brightest star in its sky. The gravitational force that nudged it may have been a passing star, another cometary body or possibly a larger trans-Neptunian object the size of Pluto and even as large as Mars or the Earth.

The forces of nature on Earth cause a constant turning over geological features. Our oceans and atmosphere are constantly recycling water and gases. The comets that we receive from the Oort Cloud are objects as old as our Solar System. Yet it is the close encounter with Mars that has raised the specter of an otherwise small ordinary comet. All these comets from deep space are fascinating gems nearly unaltered for 1/3rd of the time span of the known Universe.



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Astrophotographer Captures Dramatic Photo of Comet Siding Spring Approaching Mars

Astrophotographer Captures Dramatic Photo of Comet Siding Spring Approaching Mars:

Comet Siding Spring approaches within a degree of Mars at 5:07 a.m. CDT today October 19. Closest approach happens around 1:28 p.m. CDT (18:28 UT) when the comet will brush about 83,240 miles from the planet's surface. Image copyright SEN / Damian Peach


Comet Siding Spring approaches within a degree of Mars at 5:07 a.m. CDT today October 19. Closest approach happens around 1:28 p.m. CDT (18:28 UT) when the comet will brush about 83,240 miles from the planet’s surface. Image copyright SEN / Damian Peach
Astrophotographer Damian Peach shares this spectacular image of comet C/2013 A1 Siding Spring approaching Mars taken just hours ago.  The faint comet shows a small, condensed coma and bent tail against the glaring orange glow of the brilliant planet. Most photos of comets passing by a planet or deep sky object are lucky line-of-sight pairings with the comet in the foreground and object light years away in the background. Not this one. Both Siding Spring and Mars lie at nearly the identical distance from Earth of 151 million miles (243 million km).

Artist view of the comet passing closest to Mars this Sunday. At the time, the Mars orbiters from the U.S., Europe and India will be huddled on the opposite side of the planet to avoid possible impacts from comet dust. Credit: NASA


Artist view of the comet passing closest to Mars this afternoon October 19. At the time, the Mars orbiters from the U.S., Europe and India will be huddled on the opposite side of the planet to avoid possible impacts from comet dust. Credit: NASA
When closest to Mars this afternoon, Siding Spring is expected to shine at around magnitude -5 or about twice as bright as Venus. Mind you, that estimate considers the entire comet crunched down into a dot. But for those who remember, Comet Hale-Bopp remained at zero magnitude, 100 times fainter than Siding Spring, and made for one of the most impressive naked eye sights on spring evenings in 1997.

More recently, Comet McNaught climaxed at magnitude -5 in the daytime sky near the Sun in January 2007. It was plainly visible in binoculars and telescopes in a blue sky  if you knew exactly where to look and took care to avoid the Sun. Would-be Martians are far more fortunate, with Siding Spring appearing high overhead in a dark sky from some locations, including that of NASA’s Curiosity Rover.


Comet C/2013 Siding Spring as it rises and sets over the Curiosity Rover this weekend October 18-19. Credit: Solarsystemscope.com

Right on time for today’s encounter, the folks at Solarsystemscope.com have rolled out an interactive simulation of Comet Siding Spring’s appearance in the sky above Curiosity. Just click the play button on the control panel above to run it live. Seen from Mars, the comet bobs along Eridanus the River southwest of Orion, passing high in the southern sky overnight. What a sight!

Another photo, just in, taken of the comet and Mars today by Rolando Ligustri. Beautiful!


Another photo, just in, taken of the comet and Mars today by Rolando Ligustri. Beautiful!
The comet nucleus is only about 0.4 miles (700 meters) across, but the coma or atmosphere fluffs out to around 12,000 miles (19,300 km). Seen from the ground, Siding Spring would span about 8°of sky or 16 full Moons from head to tail. Moving at 1.5° per minute, we could watch crawl across the heavens in real time with the naked eye. Wish I zoom to Mars for a look, but the rovers and orbiters will be our eyes as they study and photograph the comet during its brief flyby. As soon as those pictures become available, we’ll publish them here. Can’t wait!


Come Siding Spring comes out the other side!

While we’re waiting, amateur astronomers have been busy shooting additional photos and creating videos from their images. Fritz Helmut Hemmerich made this video from 1200-meters at Tenerife in the Canary Islands showing Comet Siding Spring immediately after its Mars encounter. One thing we know for certain is that the comet is intact after its close brush.

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Slow-Growing Galaxies Offer Window to Early Universe

Slow-Growing Galaxies Offer Window to Early Universe:

Sluggish Galaxy Grows Stars Slowly A small galaxy, called Sextans A, is shown here in a multi-wavelength mosaic captured by the European Space Agency's Herschel mission, in which NASA is a partner, along with NASA's Galaxy Evolution Explorer (GALEX) and the National Radio Astronomy Observatory's Jansky Very Large Array observatory near Socorro, New Mexico. Image credit: ESA/NASA/JPL-Caltech/NRAO

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What makes one rose bush blossom with flowers, while another remains barren? Astronomers ask a similar question of galaxies, wondering how some flourish with star formation and others barely bloom.

A new study published in the Oct. 16 issue of the journal Nature addresses this question by making some of the most accurate measurements yet of the meager rates at which small, sluggish galaxies create stars. The report uses data from the European Space Agency's Herschel mission, in which NASA is a partner, and NASA's Spitzer Space Telescope and Galaxy Evolution Explorer (GALEX).

The findings are helping researchers figure out how the very first stars in our universe sprouted. Like the stars examined in the new study, the first-ever stars from billions of years ago took root in poor conditions. Growing stars in the early cosmos is like trying to germinate flower seeds in a bed of dry, poor soil. Back then, the universe hadn't had time yet to make "heavy metals," elements heavier than hydrogen and helium.

"The metals in space help act in some ways like a fertilizer to help stars grow," said George Helou, an author of the new study and director of NASA's Infrared Processing and Analysis Center (IPAC) at the California Institute of Technology, Pasadena. The lead author of the study is Yong Shi, who performed some of the research at IPAC before moving to Nanjing University in China.

The two slow-going galaxies in the study, called Sextans A and ESO 146-G14, lack in heavy metals, just like our young and remote cosmos, only they are a lot closer to us and easier to see. Sextans A is located about 4.5 million light-years from Earth, and ESO 146-G14 is more than 70 million light-years away.

These smaller galaxies are late bloomers. They managed to travel through history while remaining pristine, and never bulked up in heavy metals (heavy metals not only help stars to form, but are also created themselves by stars).

"The metal-poor galaxies are like islands left over from the early universe," said Helou. "Because they are relatively close to us, they are especially valuable windows to the past."

Studying star formation in poor growing environments such as these is tricky. The galaxies, though nearby, are still faint and hard to see. Shi and his international team wrangled the problem with a multi-wavelength approach. The Herschel data, captured at the longest infrared wavelengths of light, let the researchers see the cool dust in which stars are buried. The dust serves as a proxy for the total amount of gas in the region -- the basic ingredient of stars. To other telescopes, this dust is cold and invisible. Herschel, on the other hand, can pick up its feeble glow.

Supporting radio-wavelength measurements of some of the gas in the galaxies came from the National Radio Astronomy Observatory's Jansky Very Large Array observatory near Socorro, New Mexico, and the Australia Telescope Compact Array observatory, near Narrabri.

Meanwhile, archived data from Spitzer and GALEX were used to look at the rate of star formation. Spitzer sees shorter-wavelength infrared light, which comes from dust that is warmed by new stars. GALEX images capture ultraviolet light from the shining stars themselves.

Putting all these pieces together enabled the astronomers to determine that the galaxies are plodding along, creating stars at rates 10 times lower than their normal counterparts.

"Star formation is very inefficient in these environments," said Shi. "Extremely metal-poor nearby galaxies are the best way to know what went on billions of years ago."

The heavy metals in present-day galaxies help star formation to flourish through cooling effects. For a star to form, a ball of gas needs to fall in on itself with the help of its own gravity. Ultimately, the material has to become dense enough for atoms to fuse and ignite, creating starlight. But as this cloud collapses, it heats up and puffs back out again, counteracting the process. Heavy metals cool everything down by radiating away the heat, enabling the cloud to condense into a star.

How stars in the early universe were able to do this without the cooling benefits of heavy metals remains unknown.

Studies like this shine light on the very first stellar buds, giving us a glimpse into the roots of our cosmic history.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. The GALEX mission, which ended in 2013, was also managed by JPL for NASA and led by Caltech. JPL served as the NASA Herschel Project Office for the European Space Agency's Herschel mission, which also ended in 2013.

Data from Spitzer and Herschel are accessible through the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA.

Media Contact

Whitney Clavin

818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov

2014-353
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Rosetta's Comet Landing Site Close Up

Rosetta's Comet Landing Site Close Up:

An annotated mosaic from the Rosetta spacecraft An annotated mosaic from the Rosetta spacecraft shows "Site J," the primary landing site on comet 67P/Churyumov-Gerasimenko for the mission's Philae lander. Image credit: ESA/Rosetta/MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

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A mosaic from the European Space Agency's Rosetta spacecraft shows "Site J," the primary landing site on comet 67P/Churyumov-Gerasimenko for the mission's Philae lander. Rosetta is the first mission to attempt a soft landing on a comet.

The mosaic comprises two images taken by Rosetta's OSIRIS narrow-angle camera on Sept. 14, 2014, from a distance of about 19 miles (30 kilometers). The image scale is 1.6 feet (0.5 meters) per pixel. The red ellipse is centered on the landing site and is approximately 1,600 feet (500 meters) in diameter.

Site J is located on the smaller of the comet's two lobes. On Nov. 12, the Rosetta spacecraft will release Philae at 01:03 a.m. PST/10:03 CET/09:03 UTC (the time the signal is received on Earth). Touchdown of Philae on Site J is expected about seven hours later, at around 8 a.m. PST/17:00 CET/16:00 UTC (Earth Received Time).

Launched in March 2004, Rosetta was reactivated in January 2014 after a record 957 days in hibernation. Composed of an orbiter and lander, Rosetta's objectives since arriving at comet 67P/Churyumov-Gerasimenko earlier this month have been to study the celestial object up close in unprecedented detail, prepare for landing a probe on the comet's nucleus in November, and following the landing, track the comet's changes as it sweeps past the sun.

Comets are time capsules containing primitive material left over from the epoch when the sun and its planets formed. Rosetta's lander will obtain the first images taken from a comet's surface and will provide comprehensive analysis of the comet's possible primordial composition by drilling into the surface. Rosetta also will be the first spacecraft to witness at close proximity how a comet changes as it is subjected to the increasing intensity of the sun's radiation. Observations will help scientists learn more about the origin and evolution of our solar system and the role comets may have played in seeding Earth with water, and perhaps even life.

Rosetta is a European Space Agency mission with contributions from its member states and NASA. Rosetta's Philae lander is provided by a consortium led by the German Aerospace Center, Cologne; Max Planck Institute for Solar System Research, Gottingen; National Center of Space Studies of France (CNES), Paris; and the Italian Space Agency, Rome. NASA's Jet Propulsion Laboratory in Pasadena, California, a division of the California Institute of Technology, manages the U.S. participation in the Rosetta mission for NASA's Science Mission Directorate in Washington.

For more information on the U.S. instruments aboard Rosetta, visit:

http://rosetta.jpl.nasa.gov

More information about Rosetta is available at:

http://www.esa.int/rosetta

Media Contact

DC Agle

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-9011

agle@jpl.nasa.gov

Dwayne Brown
NASA Headquarters, Washington
202-358-1726
dwayne.c.brown@nasa.gov

Markus Bauer
European Space Agency, Noordwijk, Netherlands
011-31-71-565-6799
markus.bauer@esa.int

2014-356
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Cassini Caught in Hyperion's Particle Beam

Cassini Caught in Hyperion's Particle Beam:

Cassini obtained this false-color view of Saturn's moon Hyperion Cassini obtained this false-color view of Saturn's chaotically tumbling moon Hyperion during a flyby on Sept. 26, 2005. The spacecraft detected a strong electrostatic charge on the moon's surface, a first for any body other than Earth's moon. Image credit: NASA/JPL-Caltech/Space Science Institute

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Static electricity is known to play an important role on Earth's airless, dusty moon, but evidence of static charge building up on other objects in the solar system has been elusive until now. A new analysis of data from NASA's Cassini mission has revealed that, during a 2005 flyby of Saturn's moon Hyperion, the spacecraft was briefly bathed in a beam of electrons coming from the moon's electrostatically charged surface.

The finding represents the first confirmed detection of a charged surface on an object other than our moon, although it is predicted to occur on many different bodies, including asteroids and comets.

The new analysis was led by Tom Nordheim, a doctoral candidate at Mullard Space Science Laboratory (MSSL), University College London, and was published recently in the journal Geophysical Research Letters.

Hyperion is porous and icy, with a bizarre, sponge-like appearance. Its surface is continuously bombarded by ultraviolet light from the sun and exposed to a rain of charged particles -- electrons and ions -- within the invisible bubble generated by Saturn's magnetic field, called the magnetosphere. The researchers think Hyperion's exposure to this hostile space environment is the source of the particle beam that struck Cassini.

Measurements made by several of Cassini's instruments during a close encounter with Hyperion on September 26, 2005, indicate that something unexpected took place in the charged particle environment around the spacecraft. Among those instruments, the Cassini Plasma Spectrometer (CAPS) detected that the spacecraft was magnetically connected to the surface of Hyperion for a brief period, allowing electrons to escape from the moon toward the robotic probe.

Most people are familiar with the electrostatic charge buildup that occurs when a balloon is rubbed against hair or a sweater. Objects in space can also become electrostatically charged by exposure to solar ultraviolet light and incoming charged particles. The Cassini data show that a similar process can take place on Hyperion.

The finding is surprising, as the small but odd-looking moon was thought to be a simple inert object, which would not undergo any strong interactions with the Saturnian magnetosphere. Nevertheless, the team's analysis indicates that Cassini remotely detected a strongly negative voltage on Hyperion. "It was rather like Cassini receiving a 200-volt electric shock from Hyperion, even though they were over 2,000 kilometers [1,200 miles] apart at the time," said Nordheim.

Scientists had previously suggested that surface features observed on the asteroid Eros and several of Saturn's moons are due to the motion of charged dust across their surfaces. On small objects with low gravity, dust grains might even be able to overcome the force of gravity and escape into space.

Although mission controllers have detected no signs that the Hyperion electron beam caused damage to Cassini, strong electric charging effects could prove to be a hazard to future robotic and human explorers at planetary objects without atmospheres, including Earth's moon, where they could create the potential for powerful electrostatic discharges.

"Our observations show that this is also an important effect at outer planet moons and that we need to take this into account when studying how these moons interact with their environment," said Geraint Jones of MSSL, a member of the Cassini CAPS team who helped supervise the study.

Cassini's CAPS instrument was powered off in 2012, when the instrument began to draw excess current. The team is based at Southwest Research Institute, San Antonio. Part of the CAPS instrument that made the detection discussed in this research -- the CAPS electron spectrometer -- was built by MSSL.

Nordheim and colleagues also utilized data from three other Cassini instruments in their analysis: the Radio and Plasma Wave Science instrument, the Magnetospheric Imaging Instrument and the magnetometer.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington.

More information about Cassini is available at the following sites:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

Media Contact

Preston Dyches

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-7013

preston.dyches@jpl.nasa.gov

Tom Nordheim
Mullard Space Science Laboratory
University College London, United Kingdom
011 44 07504-305104
tom.nordheim.10@ucl.ac.uk

2014-357
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Saturn Moon May Hide a 'Fossil' Core or an Ocean

Saturn Moon May Hide a 'Fossil' Core or an Ocean:

This mosaic of Saturn's moon Mimas was created from images taken by Cassini This mosaic of Saturn's moon Mimas was created from images taken by NASA's Cassini spacecraft during its closest flyby of the moon on Feb. 13, 2010. Image credit: NASA/JPL-Caltech/Space Science Institute

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A new study focused on the interior of Saturn's icy moon Mimas suggests its cratered surface hides one of two intriguing possibilities: Either the moon's frozen core is shaped something like a football, or the satellite contains a liquid water ocean.

Researchers used numerous images of Mimas taken by NASA's Cassini mission to determine how much the moon wobbles as it orbits Saturn. They then evaluated several possible models for how its interior might be arranged, finding two possibilities that fit their data.The study is published in the Oct. 17 issue of the journal Science.

"The data suggest that something is not right, so to speak, inside Mimas," said Radwan Tajeddine, a Cassini research associate at Cornell University, Ithaca, New York, and lead author on the paper. "The amount of wobble we measured is double what was predicted."

Either possiblity for the interior of Mimas would be interesting, according to Tajeddine, as the moon's heavily cratered outward appearance does not suggest anything unusual lies beneath its surface. Because Mimas formed more than four billion years ago, scientists would expect its core to have relaxed into a more or less spherical shape by now. So if Mimas' core is oblong in shape, it likely represents a record of the moon's formation, frozen in time.

If Mimas possesses an ocean, it would join an exclusive club of "ocean worlds" that includes several moons of Jupiter and two other Saturn moons, Enceladus and Titan. A global ocean would be surprising, said Tajeddine, as the surface of Mimas does not display signs of geologic activity.

Like a lot of moons in the solar system, including our own, Mimas always shows essentially the same face to its parent planet. This is called a spin-orbit resonance, meaning the moon's rotation, or spin, is in sync with its orbit around Saturn. Like Earth's moon, Mimas takes the same amount of time to spin completely around on its axis as it takes to orbit its planet.

The orbit of Mimas is very slightly stretched out, forming an ellipse rather than a perfect circle. This slight deviation causes the point on Mimas' surface that faces Saturn to vary a bit over the course of an orbit -- an observer on Saturn would see Mimas wobble slightly during its orbit, causing small amounts of terrain over the limb to become visible. This effect is called libration, and Earth's moon does it as well.

"Observing libration can provide useful insights about what is going on inside a body," said Tajeddine. "In this case, it is telling us that this cratered little moon may be more complex than we thought."

Models developed by Tajeddine and co-authors from France and Belgium indicate that, if Mimas is hiding a liquid water ocean, it lies 15 to 20 miles (24 to 31 kilometers) beneath the moon's impact-battered surface. At 246 miles (396 kilometers) wide, Mimas is too small to have retained internal heat from its formation, so some other source of energy would be required to maintain an underground ocean. The researchers note that there is evidence that Mimas' current, elongated orbit could have been even more stretched out in the past, which might have created enough tidal heating to produce an ocean.

Although an ocean within Mimas would be a surprise, the authors found that the interior model they considered for an oblong core ought to give the moon a slightly different shape than what is observed. They suggest that other models could be developed to explain the moon's observed libration, and that further measurements by Cassini could help determine which model is most likely to be correct.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington. The imaging team is based at the Space Science Institute in Boulder, Colorado.

More information about Cassini is available at the following sites:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

Media Contact

Preston Dyches

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-7013

preston.dyches@jpl.nasa.gov

2014-359
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Tuesday, October 14, 2014

PICASA WEB HD GIF ANIMATED GIF - EARTH ROTATION

HD GIF ANIMATED GIF - EARTH ROTATION
#animatedGIF   #GIF   #Animation   #hdgif  :

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PICASA WEB HD GIF ANIMATED GIF - EARTH ROTATION
Date: Aug 13, 2014, 5:43 PM

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PICASA WEB OUR PLANETARY SYSTEM

OUR PLANETARY SYSTEM:

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PICASA WEB OUR PLANETARY SYSTEM
Date: Mar 30, 2009, 9:39 PM

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LUZ DO CEU WALLPAPER

1-luz-do-ceu-1820x1080.jpg:

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LUZ DO CEU WALLPAPER
Date: Sep 29, 2014, 10:28 PM

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NASA Solar Forecasting Takes A Hit As Sun-Gazing Spacecraft Stops Phoning Home

NASA Solar Forecasting Takes A Hit As Sun-Gazing Spacecraft Stops Phoning Home:

Artist's conception of one of the Solar TErrestrial RElations Observatory (STEREO) spacecraft. Credit: NASA


Artist’s conception of one of the Solar TErrestrial RElations Observatory (STEREO) spacecraft. Credit: NASA
A NASA spacecraft has been out of radio contact for about two weeks, but the agency is still holding out hopes for a rescue. One of the STEREO (Solar TErrestrial RElations Observatory) spacecraft stopped phoning home to Earth on Oct. 1 “immediately after a planned reset of the spacecraft”, NASA said in an update last week.

If the STEREO-Behind spacecraft can’t be recovered, this could cause a data gap in the mission next year — which is unique because it looks at the far side of the Sun. On the website, NASA didn’t say how badly solar weather forecasts are affected, but in other materials they have said both STEREO spacecraft are a crucial part of this work.

STEREO’s pair of satellites (STEREO-Ahead and STEREO-Behind) aim to better map Sun eruptions (known as “coronal mass ejections”) whose charged particles can disrupt satellite communications during solar storms. The mission has been ongoing since 2006 and they’ve viewed the far side of the Sun since 2011. What caused one of them to stop talking to us is unknown, but NASA said recovery attempts are ongoing.

The satellites’ orbits around the Sun are similar to the Earth’s, but one circles a bit faster and the other a bit slower. Next year, geometry (a solar conjunction) means the Sun will block our view of one of the spacecraft at a time. As NASA explained in a July update, “radio receivers on Earth will not be able to distinguish STEREO’s signal from the sun’s radiation.”



This is affecting the mission in two ways. First, there is a period where the antennas on the spacecraft must be repositioned to avoid getting cooked by the Sun. Some data will flow, but it will be in lower resolution. STEREO-Ahead entered this period on Aug. 20, and STEREO-Behind was supposed to send high-resolution data until Dec. 1.

Then there’s a time when each spacecraft will be completely blocked by the Sun. STEREO-Behind was supposed to enter this period from Jan. 22 to March 23, 2015, with its twin still collecting data at this time. But then will come a period where STEREO-Ahead will be out of contact: March 24 to July 7, 2015. If STEREO-Behind can’t fill in for STEREO-Ahead at this time as planned, a data gap could loom.

Lower-resolution data is then expected from STEREO until 2016, when the geometry means the spacecraft can safely reposition their antennas. While these aren’t the only sun-gazing spacecraft — real-time data is still flowing from the Solar Dynamics Observatory (SDO) and the Solar and Heliospheric Observatory (SOHO) — NASA has said that the lower data rate and losing contact with one STEREO spacecraft next year will be difficult for solar forecasting.

“Lack of STEREO observations used in NASA research models will severely limit the forecasting of solar storms throughout the solar system,” the agency said in a July Q&A about the 2015 data losses.



About 

Elizabeth Howell is the senior writer at Universe Today. She also works for Space.com, Space Exploration Network, the NASA Lunar Science Institute, NASA Astrobiology Magazine and LiveScience, among others. Career highlights include watching three shuttle launches, and going on a two-week simulated Mars expedition in rural Utah. You can follow her on Twitter @howellspace or contact her at her website.
Tagged as: solar conjunction, STEREO, stereo-ahead, stereo-behind

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