Universe Today

February 16, 2017February 17, 2017 by Ken Kremer

At T Minus 1 Day from ISS Liftoff SpaceX Rolls Falcon 9 to KSC Pad 39A – Feb. 18 Ignition Hinges on FAA License Approval

SpaceX Falcon 9 rocket rests horizontal atop Launch Complex 39-A at the Kennedy Space Center on 16 Feb 2017 as seen from Launch Complex 39-B. This is the first rocket rolled out to launch from pad 39A since the retirement of NASA’s Space Shuttles in July 2011. Liftoff slated for 18 Feb. Credit: Ken Kremer/Kenkremer.com

KENNEDY SPACE CENTER, FL – Its getting down to the wire at T Minus 1 Day from liftoff for SpaceX and NASA as a Falcon 9 rocket was rolled out to historic Launch Complex 39A today, Feb 16, and the Feb. 18 ignition to the space station hinges on the approval of a launch license yet to be granted, the Federal Aviation Administration (FAA) confirmed late today to Universe Today.

“My previous background still applies,” FAA spokesman Hank Price confirmed to Universe Today.

“The FAA is working closely with SpaceX to ensure the activity described in the application meets all applicable regulations for a launch license.”

“The FAA will continue to work with SpaceX to provide a license determination in a timely manner.”

Blastoff of the Falcon 9 from seaside pad 39A at NASA’s Kennedy Space Center in Florida is slated for 10:01 a.m. EST Saturday, Feb. 18.

NASA plans live coverage of the launch beginning at 8:30 a.m. on NASA Television and the agency’s website.

SpaceX currently has license applications pending with the FAA for both the NASA cargo launch and pad 39A. No commercial launch can take place without FAA approval.

No License, No Launch – that’s the bottom line!

Assuming the FAA grants a launch license at the last minute on Friday the weather outlook currently is iffy for Saturday with a 60% chance of favorable conditions at launch time. The concerns are for rains and clouds according to Air Force weather forecasters.

In case of a scrub for any reason on Feb. 18, the backup launch opportunity is 9:38 a.m. Sunday, Feb. 19.

Technically all appears to be on track for the historic first launch of a Falcon 9 from pad 39A pending further reviews and updates from NASA and SpaceX on Friday.

First SpaceX Falcon 9 rocket atop Launch Complex 39-A at the Kennedy Space Center comes to life with successful static hot fire test at 430 p.m. on 12 Feb 2017 as seen from Space View Park, Titusville, Fl. This is the first rocket to stand on pad 39A since the retirement of NASA’s Space Shuttles in July 2011. Credit: Ken Kremer/Kenkremer.com

After a successful static fire test of the two stage rocket and all nine first stage Merlin 1D engines on Sunday afternoon, Feb. 12, the path to orbit was cleared for a critical Dragon cargo flight for NASA to deliver over two and a half tons of science and supplies on the CRS-10 resupply mission to the six person crew living and working on the International Space Station (ISS).

First SpaceX Falcon 9 rocket minus Dragon spacecraft stands erect atop Launch Complex 39-A at the Kennedy Space Center as seen from Playalinda Beach, Fl, following static fire test on 12 Feb 2017. This is the first rocket to stand on pad 39A since the retirement of NASA’s Space Shuttles in July 2011. Liftoff to the ISS is slated for 18 Feb 2017 on the CRS-10 resupply mission for NASA. Credit: Ken Kremer/Kenkremer.com

The SpaceX Falcon 9 rocket was then integrated with the unmanned Dragon CRS-10 cargo freighter was rolled out of the SpaceX processing hangar at the perimeter fence and then up the incline to the top of pad 39A this morning using a dedicated transporter-erector, so crew could begin final preparation for the Saturday morning blastoff.

From atop KSC pad 39B I witnessed the rocket residing horizontally atop pad 39A as technicians further moved the rocket to launch position.

The 22 story tall Falcon 9/Dragon vehicle was erected to vertical launch position later this afternoon at about 4:50 p.m. to conduct additional ground checks and testing.

It will again be lowered to the horizontal position, so that late load cargo items can be stowed inside the Dragon spaceship on Friday before raising the rocket again into the final launch configuration.

This marks the first time any fully integrated rocket has stood on pad 39A for a scheduled launch since the retirement of NASA’s Space Shuttles in July 2011 on the STS-135 mission to the space station.

The historic NASA launch pad was formerly used to launch both America’s space shuttles and astronauts on Apollo/Saturn V moon landing missions as far back as the 1960s.

Dragon is carrying more than 5500 pounds of equipment, gear, food, crew supplies, hardware and NASA’s Stratospheric Aerosol Gas Experiment III (SAGE III) ozone mapping science payload in support of the Expedition 50 and 51 crew members.

SAGE III will measure stratospheric ozone, aerosols, and other trace gases by locking onto the sun or moon and scanning a thin profile of the atmosphere.

The LIS lightning mapper will measure lightning from the altitude of the ISS. NASA’s RAVEN experiment will test autonomous docking technologies for spacecraft.

Engineers at work processing NASA’s Stratospheric Aerosol and Gas Experiment III, or SAGE III instrument inside the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida during exclusive visit by Ken Kremer/Universe Today in December 2016. Technicians are working in a super-clean ‘tent’ built in the SSPF high bay to protect SAGE III’s special optics and process the Ozone mapper for upcoming launch on the SpaceX CRS-10 Dragon cargo flight to the International Space Station in early 2017. Credit: Ken Kremer/kenkremer.com

The research supplies and equipment brought up by Dragon will support over 250 scientific investigations to advance knowledge about the medical, psychological and biomedical challenges astronauts face during long-duration spaceflight.

About 10 minutes after launch, Dragon will reach its preliminary orbit, deploy its solar arrays and begin a carefully choreographed series of thruster firings to reach the space station.

As a secondary objective SpaceX s planning to attempt to land its Falcon 9 first stage on land at Landing Zone 1 at Cape Canaveral Air Force Station.

‘Astronauts Shane Kimbrough of NASA and Thomas Pesquet of ESA (European Space Agency) will use the station’s robotic arm to capture Dragon when it arrives at the space station after its two-day journey. The spacecraft will be berthed to the Earth-facing port on the Harmony module. The following day, the space station crew will pressurize the vestibule between the station and Dragon, then open the hatch that leads to the forward bulkhead of Dragon,’ according to NASA.

Pad 39A has lain dormant for launches for nearly six years since Space Shuttle Atlantis launched on the final shuttle mission STS 135 in July 2011.

Watch for Ken’s onsite CRS-10 mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.

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

Ken Kremer

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Learn more about SpaceX CRS-10 launch to ISS, ULA SBIRS GEO 3 launch, EchoStar launch GOES-R launch, Heroes and Legends at KSCVC, OSIRIS-REx, InSight Mars lander, ULA, SpaceX and Orbital ATK missions, Juno at Jupiter, SpaceX AMOS-6, ISS, ULA Atlas and Delta rockets, Orbital ATK Cygnus, Boeing, Space Taxis, Mars rovers, Orion, SLS, Antares, NASA missions and more at Ken’s upcoming outreach events at Kennedy Space Center Quality Inn, Titusville, FL:

Feb 17- 19: “SpaceX CRS-10 launch to ISS, ULA Atlas SBIRS GEO 3 launch, EchoStar 19 comsat launch, GOES-R weather satellite launch, OSIRIS-Rex, SpaceX and Orbital ATK missions to the ISS, Juno at Jupiter, ULA Delta 4 Heavy spy satellite, SLS, Orion, Commercial crew, Curiosity explores Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings

February 16, 2017February 16, 2017 by Nancy Atkinson

Will You Be The Discoverer Of Planet 9?

Artist concept of Planet 9. Credit: NASA/JPL-Caltech.

Citizen science projects are a great way for anyone to be involved in the scientific process. Average, everyday folks have discovered things like supernovae, previously unseen craters on the Moon and Mars and even new planets orbiting a distant star.

Now, you could be part of one of the most exciting quests yet: finding a mysterious, unseen planet in the far reaches of our own solar system. Last year, Caltech astronomers Mike Brown and Konstantin Batygin found indirect evidence for the existence of a large planet, likely located out past Pluto, and since then, the search has been on. But so far, it has come up empty. And so, astronomers decided they would bring in a little help: You.

“Backyard Worlds: Planet 9 has the potential to unlock once-in-a-century discoveries, and it’s exciting to think they could be spotted first by a citizen scientist,” said UC Berkeley postdoctoral researcher Aaron Meisner, who is helping to head up this latest citizen science project.

A previously cataloged brown dwarf named WISE 0855?0714 shows up as a moving
orange dot (upper left) in this loop of WISE images spanning five years. By viewing
movies like this, anyone can help discover more brown dwarfs or even a 9th planet. Credit: NASA/WISE.

People who sign on to the Backyard World: Planet 9 website will be basically using the same type of technique that was used to find the last planet discovered in our solar system, Pluto. Clyde Tombaugh used a special machine that systematically switched images on glass astronomical plates back and forth, looking for any objects in the night sky that ‘moved’ between the images.

For Backyard Worlds: Planet 9, users will view brief “flipbook” movies made from images captured by NASA’s Wide-field Infrared Survey Explorer (WISE) mission. A faint spot seen moving through background stars might be a new and distant planet in our solar system. Or it could be a nearby brown dwarf star, which would be another exciting discovery.

WISE’s infrared images cover the entire sky about six times over. This has allowed astronomers to search the images for faint, glowing objects that change position over time, which means they are relatively close to Earth. Objects that produce their own faint infrared glow would have to be large, Neptune-size planets or brown dwarfs, which are slightly smaller than stars. WISE images have already turned up hundreds of previously unknown brown dwarfs, including the objects fairly close to us, so astronomers hope that the Backyard Worlds search will turn up a new nearest neighbor to our sun.

NASA wants to bring in all the humans it can for this search, because the human eye is much better than computers at seeing changes between images.

“Automated searches don’t work well in some regions of the sky, like the plane of the Milky Way galaxy, because there are too many stars, which confuses the search algorithm,” said Meisner.

“There are just over four light-years between Neptune, the farthest known planet in our solar system, and Proxima Centauri, the nearest star, and much of this vast territory is unexplored,” said NASA astronomer Marc Kuchner, the lead researcher and an astrophysicist at NASA’s Goddard Space Flight Center. “Because there’s so little sunlight, even large objects in that region barely shine in visible light. But by looking in the infrared, WISE may have imaged objects we otherwise would have missed.”

Check out Backyard Worlds: Planet 9 here, and give Universe Today the scoop when you make your big discovery!

You can find more info in the video below:

Source: UC Berkeley

February 16, 2017February 16, 2017 by Matt Williams

What is the Weather like on Saturn?

The Saturn hexagon as seen by Voyager 1 in 1980 (NASA)

Welcome back to our planetary weather series! Next up, we take a look at the ringed-beauty, Saturn!

Saturn is famous for many things. Aside from its ring system, which are the most visible and beautiful of any gas giant, it is also known for its extensive system of moons (the second largest in the Solar System behind Jupiter). And then there its banded appearance and gold color, which are the result of its peculiar composition and persistent weather patterns.

Much like Jupiter, Saturn’s weather systems are known for being particularly extreme, giving rise to features that can be seen from great distances. It’s high winds periodically create massive oval-shaped storms, jet streams, hurricanes, and hexagonal wave patterns that are visible in both the northern and southern polar regions.

Saturn’s Atmosphere:

The outer atmosphere of Saturn contains 96.3% molecular hydrogen and 3.25% helium by volume. The gas giant is also known to contain heavier elements, though the proportions of these relative to hydrogen and helium is not known. It is assumed that they would match the primordial abundance from the formation of the Solar System.

The huge storm churning through the atmosphere in Saturn’s northern hemisphere overtakes itself as it encircles the planet in this true-color view from NASA’s Cassini spacecraft. Credit: NASA/JPL-Caltech/SSI

Trace amounts of ammonia, acetylene, ethane, propane, phosphine and methane have been also detected in Saturn’s atmosphere. The upper clouds are composed of ammonia crystals, while the lower level clouds appear to consist of either ammonium hydrosulfide (NH₄SH) or water. Ultraviolet radiation from the Sun causes methane photolysis in the upper atmosphere, leading to a series of hydrocarbon chemical reactions with the resulting products being carried downward by eddies and diffusion.

Saturn’s atmosphere exhibits a banded pattern similar to Jupiter’s, but Saturn’s bands are much fainter and wider near the equator. As with Jupiter’s cloud layers, they are divided into the upper and lower layers, which vary in composition based on depth and pressure. In the upper cloud layers, with temperatures in range of 100–160 K and pressures between 0.5–2 bar, the clouds consist of ammonia ice.

The presence of hydrogen gas results in clouds of deep red. However, these are obscured by clouds of ammonia, which are closer to the outer edge of the atmosphere and cover the entire planet. The exposure of this ammonia to the Sun’s ultraviolet radiation causes it to appear white. Combined with its deeper red clouds, this results in the planet having a pale gold color.

Water ice clouds begin at a level where the pressure is about 2.5 bar and extend down to 9.5 bar, where temperatures range from 185–270 K. Intermixed in this layer is a band of ammonium hydrosulfide ice, lying in the pressure range 3–6 bar with temperatures of 290–235 K. Finally, the lower layers, where pressures are between 10–20 bar and temperatures are 270–330 K, contains a region of water droplets with ammonia in an aqueous solution.

Great White Spot:

On occasion, Saturn’s atmosphere exhibits long-lived ovals, similar to what is commonly observed on Jupiter. Whereas Jupiter has the Great Red Spot, Saturn periodically has what’s known as the Great White Spot (aka. Great White Oval). This unique but short-lived phenomenon occurs once every Saturnian year, roughly every 30 Earth years, around the time of the northern hemisphere’s summer solstice.

These spots can be several thousands of kilometers wide, and have been observed in 1876, 1903, 1933, 1960, and 1990. Since 2010, a large band of white clouds called the Northern Electrostatic Disturbance have been observed enveloping Saturn, which was spotted by the Cassini space probe. If the periodic nature of these storms is maintained, another one will occur in about 2020.

Meteorological Phenomena:

The winds on Saturn are the second fastest among the Solar System’s planets, after Neptune’s. This is due in part to Saturn’s high rotational velocity – which is 9.87 km/s (6.13 mi/s), which works out to 35,500 km/h (22,058.7 mi/h). At this rate, it only takes the planet 10 hours 33 minutes to rotate once on its axis. However, due to it being a gas giant, there is a difference between the rotation of its atmosphere and its core.

Data obtained by the Voyager 1 and 2 missions indicated peak easterly winds of 500 m/s (1800 km/h). Saturn’s northern and southern poles have also shown evidence of stormy weather. At the north pole, this takes the form of a hexagonal wave pattern, whereas the south shows evidence of a massive jet stream.

*Saturn makes a beautifully striped ornament in this natural-color image, showing its north polar hexagon and central vortex. Credit: NASA/JPL-Caltech/Space Science Institute*

The persisting hexagonal wave pattern around the north pole was first noted in the Voyager images. The sides of the hexagon are each about 13,800 km (8,600 mi) long (which is longer than the diameter of the Earth) and the structure rotates with a period of 10h 39m 24s, which is assumed to be equal to the period of rotation of Saturn’s interior.

The south pole vortex, meanwhile, was first observed using the Hubble Space Telescope. These images indicated the presence of a jet stream, but not a hexagonal standing wave. These storms are estimated to be generating winds of 550 km/h, are comparable in size to Earth, and believed to have been going on for billions of years.

In 2006, the Cassini space probe observed a hurricane-like storm that had a clearly defined eye. Such storms had not been observed on any planet other than Earth – even on Jupiter. This storm appeared to be caused by heat that was generated in the depths of the warm interior of Saturn, which then escaped to the upper atmosphere and escaped the planet.

Saturn has also been noted for its “string of pearls” feature, which was captured by Cassini’s visual and infrared mapping spectrometer in 2006. This feature, which appeared in it’s northern latitudes (and has not been seen on any other gas giant) is a series of cloud clearings spaced at regular intervals that show how Saturn’s atmosphere is lit by its own internal, thermal glow.

So how is the weather on Saturn? Pretty violent and stormy! And not surprising given the planet’s mass, composition, powerful gravity, and rapid rotation. Makes you feel happy we live on Earth, where the Earth is (comparatively speaking) pretty calm and boring!

We have written many interesting articles about planetary weather here at Universe Today. Here’s What’s the Weather Like on Mercury?, What’s the Weather Like on Venus?, What’s the Weather Like on Mars?, What’s the Weather Like on Jupiter?, What is the Weather Like on Uranus? and What is the Weather Like on Neptune?

For more information, check out NASA’s Solar System Exploration – Saturn, and the facts about Saturn from Space Facts.

Astronomy Cast has recorded some interesting episode on the subject. Here’s Episode 59: Saturn, and Episode 61: Saturn’s Moons.

Sources:

February 16, 2017February 19, 2017 by Ken Kremer

NASA To Study Launching Astronauts on 1st SLS/Orion Flight

NASA’s Space Launch System (SLS) blasts off from launch pad 39B at the Kennedy Space Center in this artist rendering showing a view of the liftoff of the Block 1 70-metric-ton (77-ton) crew vehicle configuration. Credit: NASA/MSFC

KENNEDY SPACE CENTER, FL – In a potentially major change in direction for NASA’s human spaceflight architecture, the agency is officially studying the possibility of adding a crew of astronauts to the first flight of the Orion deep space crew capsule and the heavy lift Space Launch System (SLS) rocket currently in development, announced Acting NASA Administrator Robert Lightfoot.

Lightfoot made the announcement in a speech to the Space Launch System/Orion Suppliers Conference in Washington, D.C. as well as an agency wide memo circulated to NASA employees on Wednesday, Feb. 15.

The move, if implemented, for the first joint SLS/Orion flight on Exploration Mission-1 (EM-1) would advance the date for sending American astronauts back to the Moon by several years – from the next decade into this decade.

Lightfoot has directed Bill Gerstenmaier, associate administrator for the Human Exploration and Operations Mission Directorate, to start detailed studies of what it would take to host astronauts inside the Orion EM-1 crew capsule.

“I have asked Bill Gerstenmaier to initiate a study to assess the feasibility of adding a crew to Exploration Mission-1, the first integrated flight of SLS and Orion,” Lightfoot said.

NASA’s current plans call for the unmanned blastoff of Orion EM-1 on the SLS-1 rocket later next year on the first test flight – roughly in the September to November timeframe from Launch Complex 39B at the Kennedy Space Center.

“The study will examine the opportunities it could present to accelerate the effort of the first crewed flight and what it would take to accomplish that first step of pushing humans farther into space,” NASA officials added in a statement.

But because of all the extra work required to upgrade a host of systems for both Orion and SLS for humans ahead of schedule, liftoff of that inaugural mission would have to slip by at least a year or more.

“I know the challenges associated with such a proposition, like reviewing the technical feasibility, additional resources needed, and clearly the extra work would require a different launch date” Lighfoot elaborated.

“That said, I also want to hear about the opportunities it could present to accelerate the effort of the first crewed flight and what it would take to accomplish that first step of pushing humans farther into space.”

Orion crew module pressure vessel for NASA’s Exploration Mission-1 (EM-1) is unveiled for the first time on Feb. 3, 2016 after arrival at the agency’s Kennedy Space Center (KSC) in Florida. It is secured for processing in a test stand called the birdcage in the high bay inside the Neil Armstrong Operations and Checkout (O&C) Building at KSC. Launch to the Moon is slated in 2018 atop the SLS rocket. Credit: Ken Kremer/kenkremer.com

The Orion EM-1 capsule is currently being manufactured at the Kennedy Space Center.

Components of the SLS-1 rocket are being manufactured at NASA’s Michoud Assembly Facility and elsewhere around the country by numerous suppliers.

Welding is nearly complete on the liquid hydrogen tank will provide the fuel for the first flight of NASA’s new rocket, the Space Launch System, with the Orion spacecraft in 2018. The tank has now completed welding on the Vertical Assembly Center at NASA’s Michoud Assembly Facility in New Orleans. Credit: Ken Kremer/kenkremer.com

The 2018 launch of NASA’s Orion on the unpiloted EM-1 mission counts as the first joint flight of SLS and Orion, and the first flight of a human rated spacecraft to deep space since the Apollo Moon landing era ended more than 4 decades ago.

Now it might actually include humans.

Details to follow.

An artist’s interpretation of NASA’s Space Launch System Block 1 configuration with an Orion vehicle. Image: NASA

Orion is designed to send astronauts deeper into space than ever before, including missions to the Moon, asteroids and the Red Planet.

The liquid hydrogen tank qualification test article for NASA’s new Space Launch System (SLS) heavy lift rocket lies horizontally after final welding was completed at NASA’s Michoud Assembly Facility in New Orleans in July 2016. Credit: Ken Kremer/kenkremer.com

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

Ken Kremer

This artist concept depicts the Space Launch System rocket rolling out of the Vehicle Assembly Building at NASA’s Kennedy Space Center. SLS will be the most powerful rocket ever built and will launch the agency’s Orion spacecraft into a new era of exploration to destinations beyond low-Earth orbit. Credits: NASA/Marshall Space Flight Center

February 15, 2017February 15, 2017 by Bob King

Video of Green Comet 45P Puts You Close To The Action

Comet 45P is seen here on Feb. 8, 2017. The comet appears very spread out and diffuse. While its overall brightness is about magnitude +8.5, the comet appears diffuse and faint. Credit: Chris Schur

This animation of comet 45P/H-M-P is composed of thirteen delay-Doppler images made during 2 hours of observation using the Arecibo Observatory on Feb. 12. Credit: USRA

Comets hide their central engines well. From Earth, we see a bright, fuzzy coma and a tail or two. But the nucleus, the source of all the hubbub, remains deeply camouflaged by dust, at best appearing like a blurry star.

To see one up close, you need to send a spacecraft right into the comet’s coma and risk getting. Or you can do the job much more cheaply by bouncing radio waves off the nucleus and studying the returning echoes to create a shadowy image.

Although crude compared to optical photos of moons and planets, radar images reveal much about an asteroid including surface details like mountains, craters, shape and rotation rate. They’re also far superior to what optical telescopes can resolve when it comes to asteroids, which, as their name implies, appear star-like or nearly so in even large professional telescopes.

On Feb. 11, green-glowing comet 45P/Honda-Mrkos-Pajdusakova, made an unusually close pass of Earth, zipping just 7.7 million miles away. Astronomers made the most of the encounter by pressing the huge 1,000-foot-wide (305 meters) Arecibo radio dish into service to image the comet’s nucleus during and after closest approach.

Arecibo Observatory, the world’s biggest single dish radio telescope, was and is still being used to image comet 45P/H-M-P. Courtesy of the NAIC – Arecibo Observatory, a facility of the NSF

“The Arecibo Observatory planetary radar system can pierce through the comet’s coma and allows us to study the surface properties, size, shape, rotation, and geology of the comet nucleus”, said Dr. Patrick Taylor, USRA Scientist and Group Lead for Planetary Radar at Arecibo.

The two lobes of comet 67P/C-G stand out clearly in this photo taken by ESA’s Rosetta spacecraft while in orbit about the comet on March 6, 2015. Credit: ESA/Rosetta

Does the shape ring a bell? Remember Rubber Ducky? It doesn’t take a rocket scientist to see that the comet’s heart resembles the twin-lobed comet 67P/Churyumov-Gerasimenko orbited by ESA’s Rosetta spacecraft. Using the dish, astronomers have seen bright regions and structures on the comet; they also discovered that the nucleus is a little larger than expected with a diameter of 0.8 mile (1.3 km) and rotates about once every 7.6 hours. Go to bed at 10 and wake up at 6 and the comet will have made one complete turn.

Comet 45P is seen here on Feb. 8, 2017. While its overall brightness is about magnitude +8.5, the comet appears diffuse and rather faint. From dark skies, it remains a binocular object at least for a little while. Credit: Chris Schur

Radio observations of 45P/H-M-P will continue through Feb. 17. Right now, the comet is happily back in the evening sky and still visible with 10×50 or larger binoculars around 10-11 p.m. local time in the east. I spotted it low in Bootes last night about 15 minutes before moonrise under excellent, dark sky conditions. It looked like a faint, smoky ball nearly as big as the full moon or about 30 arc minutes across.

This week, the pale green blob (the green’s from fluorescing carbon), vaults upward from Bootes, crosses Canes Venatici and zooms into Coma Berenices. For maps to help you track and find it night by night, please click here. I suggest larger binoculars 50mm and up or a 6-inch or larger telescope. Be sure to use low power — the comet’s so big, you need a wide field of view to get dark sky around it in order to see it more clearly.

Very few comets pass near Earth compared to the number of asteroids that routinely do. That’s one reason 45P is only the seventh imaged using radar; rarely are we treated to such detailed views!

February 15, 2017 by Matt Williams

India Sets Record With 104 Satellites In Single Launch

The thirty-ninth flight of the ISRO's Polar Satellite Launch Vehicle (PSLV-C37), which successfully from Satish Dhawan Space Centre SHAR, Sriharikota on February 15th, 2017. Credit: ISRO

India’s national space agency – the Indian Space Research Organization (ISRO) – has come a long way in recent years. In 2008, the agency launched its first lunar explorer, Chandrayaan-1, which also deployed a lander (the Moon Impact Probe) to the surface. And then there was the Mangalayaan mission – aka. the Mars Orbiter Mission (MOM) – which made history on Sept. 24th, 2014, when it became the first probe to enter orbit around Mars on the first try.

In their latest feat, the ISRO established a new record for the number of satellites launched in a single mission. In what was the thirty-ninth launch of the Polar Satellite Launch Vehicle (PSLV), the organization deployed 104 satellites into orbit. In so doing, they have effectively overtaken the previous record of 37 – which was established by Roscosmos in June of 2014.

This launch was also the thirty eighth successful mission in a row for the PSLV. which has been in service since the early 1990s. Prior to this flight, the rocket had successfully launched a total of 71 satellites and spacecraft – 31 of which were Indian – into a variety of orbits. The most satellites it launched at one time was 20, which took place on June 22nd, 2016, with the launch of the PSLV-C34 mission.

*The thirty-sixth launch of the ISROs India’s Polar Satellite Launch Vehicle (PSLV-C34), in June 2016. Credit: ISRO*

Hence, it has not only beaten its own record this single launch (and by a factor of five, no less), but more than doubled the total amount of satellites it has deployed. This mission also pushed the total number of Indian-made satellites sent into space aboard the PSLV rocket to 46, and the number of customer satellites that India has launched to 180.

As the ISRO reported shortly after the launch:

“PSLV-C37 lifted off at 0928 hrs (9:28 am) IST, as planned, from the First Launch Pad. After a flight of 16 minutes 48 seconds, the satellites achieved a polar Sun Synchronous Orbit of 506 km inclined at an angle of 97.46 degree to the equator (very close to the intended orbit) and in the succeeding 12 minutes, all the 104 satellites successfully separated from the PSLV fourth stage in a predetermined sequence beginning with Cartosat-2 series satellite, followed by INS-1 and INS-2.”

Shortly after the launch, Prime Minister Narendra Modi, took to Twitter to congratulate the scientists and laud the space agency for its record-breaking accomplishment. “This remarkable feat by @isro is yet another proud moment for our space scientific community and the nation. India salutes our scientists,” he tweeted. “Congratulations to @isro for the successful launch of PSLV-C37 and CARTOSAT satellite together with 103 nano satellites!”

*A Cartosat-2 Series Satellite undergoing a panel deployment test at ISAC Bengaluru. Credit: ISRO*

The cargo consisted of a Cartosat-2 Series Satellite, which is the latest in a series of ISRO Earth-observation satellites. In the coming days, the satellite will position itself and begin to provide remote sensing services using its state-of-the-art panchromatic (PAN) camera – which takes black and white pictures of the Earth in the visible and EM spectrum – and its multi-spectral (color) cameras.

In addition, two technology demonstration satellites from India were deployed – the Nano Satellite-1 (INS-1) and INS-2. The remaining 101 co-passenger satellites were all the property of the ISRO’s international customers – with 96 coming from the US, and five coming from the Netherlands, Switzerland, Israel, Kazakhstan and the United Arab Emirates, respectively.

In addition to demonstrating the capability of India’s launch workhorse, this latest mission also shows the growing importance countries like India play in the modern space age. In the coming years, the ISRO hopes to commence its proposed human spaceflight program, which if successful will make it the fourth nation to conduct crewed missions to space (alongside NASA, Roscosmos, and China).

And be sure to check out the video below for footage of the PSLV-C37 mission’s liftoff and on-board camera video:

Further Reading: ISRO

February 15, 2017April 16, 2017 by Matt Williams

The Orbit of Mercury. How Long is a Year on Mercury?

A global view of Mercury, as seen by MESSENGER. Credit: NASA

Mercury is a planet of extremes. As the closest planet to our Sun, it experiences extremely high surface temperatures. But since it has virtually no atmosphere to speak of, and rotates very slowly on its axis, it gravitates between extremes of hot and cold. It also means that it’s Sun-facing side experiences prolonged periods of day while its dark side experiences extremely long periods of night.

It’s proximity to the Sun also means that it orbits the planet quite rapidly. To break it down, Mercury takes roughly 88 Earth days to complete a single orbit around the Sun. Between this rapid orbital period and its slow rotational period, a single year on Mercury is actually shorter than a single day!

Orbital Period:

Mercury orbits the Sun at a distance of 57,909,050 km (35,983,015 mi), which works out to o.387 AU – or slightly more than one-third the distance between the Sun and the Earth. It’s orbit is also highly eccentric, ranging from a distance of 46 million km/28.58 million mi at its closest (perihelion) to 70 million km/43.49 million mi at its most distant (aphelion).

*Illustration of the orbit of Kepler-432b (inner, red) in comparison to the orbit of Mercury around the Sun (outer, orange). Credit: Dr. Sabine Reffert.*

Like all the planets, Mercury moves fastest when it is at its closest point to the Sun, and slowest when it is at its farthest. However, it’s proximity to the Sun means that its average orbital velocity is a speedy 47.362 kilometers a second or 29.429 miles per second – approximately 170,500 km/h; 105,945 mph.

At this rate, it takes Mercury 87.969 days, or the equivalent of 0.24 Earth years, to complete a single orbit of the Sun. Thus, it can be said that a year on Mercury lasts almost as long as 3 months here on Earth.

Sidereal and Solar Day:

Astronomers used to think that Mercury was tidally locked to the Sun, where its rotational period matched its orbital period. This would mean that the same side it always pointed towards the Sun, thus ensuring that one side was perennially sunny (and extremely hot) while the other experienced constant night (and freezing cold).

However, improved observations and studies of the planet have led scientists to conclude that in fact, the planet has a slow rotational period of 58.646 days. Compared to its orbital period of 88 days, this means that Mercury has a spin-orbit resonance of 3:2, which means that the planet makes three completes rotations on its axis for every two orbits it makes around the Sun.

Another consequences of its spin-orbit resonance is that there is a significance difference between the time it takes the planet to rotate once on its axis (a sidereal day) and the time it takes for the Sun to reappear in the same place in the sky (a solar day). On Mercury, it takes a 176 days for the Sun to rise, set, and return to the same place in the sky. This means, effectively, that a single day on Mercury lasts as long as two years!

Yes, Mercury is a pretty extreme place. Not only do temperatures on its surface range from molten hot to freezing cold, but a single day lasts as long as six months here on Earth. Add to that the fact that it has virtually no atmosphere, and is exposed to extreme amounts of radiation, and you can begin to understand why life cannot exist there.

At least… not yet!

We have written many interesting articles about Mercury here at Universe Today. Here’s How Long is a Day on Mercury?, How Long is a Year on the Other Planets?, Which Planet has the Longest Day?, How Long is a Year on Venus?, How Long is a Year on Earth?, How Long is a Year on Mars?, How Long is a Year on Jupiter?, How Long is a Year on Saturn?, How Long is a Year on Uranus?, How Long is a Year on Neptune?, and How Long is a Year on Pluto?

If you’d like more info on Mercury, check out NASA’s Solar System Exploration Guide, and here’s a link to NASA’s MESSENGER Misson Page.

We’ve also recorded an entire episode of Astronomy Cast all about Mercury. Listen here, Episode 49: Mercury.

Sources:

February 15, 2017February 15, 2017 by Evan Gough

Dream Chaser Spacecraft May Be Used For Hubble Repair Mission

The Dream Chaser Space System, built by the Sierra Nevada Corporation, may be used for one more servicing mission to the Hubble Space Telescope. Image: By NASA - http://mediaarchive.ksc.nasa.gov/detail.cfm?mediaid=66081, Public Domain, https://commons.wikimedia.org/w/index.php?curid=27237176

The final servicing mission to the venerable Hubble Space Telescope (HST) was in 2009. The shuttle Atlantis completed that mission (STS-125,) and several components were repaired and replaced, including the installation of improved batteries. The HST is expected to function until 2030 – 2040. With the retiring of the shuttle program in 2011, it looked like the Hubble mission was destined to play itself out.

But now there’s talk of another servicing mission to the Hubble, to be performed by the Dream Chaser Space System.

A view of the Hubble Space Telescope from inside space shuttle Atlantis on mission STS-125 in 2009, the final repair mission. Credit: NASA

The Hubble was originally deployed by the Space Shuttle Discovery in 1990. It was serviced by crew aboard the shuttles 5 times on 5 different shuttle missions. Unlike the other observatories in NASA’s Great Observatories, the Hubble was designed to be serviced during its lifetime.

Those servicing missions, which took place in 1993, 1997, 1999, 2002, and 2009, were complex missions which required coordination between the Kennedy Space Center, Johnson Space Center, and the Goddard Space Flight Center. Grasping Hubble with the robotic Canadarm and placing it inside the shuttle bay was a methodical process. So was the repair and replacement of components, and the testing of components once Hubble was removed from the cargo bay. Though complicated, these missions were ultimately successful, and the Hubble is still operating.

The robotic Canadarm during STS-72, as Space Shuttle Endeavour mission in 1996. Image: By NASA – https://archive.org/details/STS072-722-041, Public Domain, https://commons.wikimedia.org/w/index.php?curid=29803999

A future servicing mission to the Hubble would be a sort of insurance policy in case there are problems with NASA’s new flagship telescope, the James Webb Space Telescope (JWST.) The JWST is due to be launched in 2018, and its capabilities greatly exceed those of the Hubble. But the James Webb’s destination is LaGrange Point 2 (L2), a stable point in space about 1.5 million km (932,000 miles) from Earth. It will enter a halo orbit around L2, which makes a repair mission difficult. Though deployment problems with the JWST could be corrected by visiting spacecraft, the Telescope itself is not designed to be repaired like the Hubble is.

Since the JWST is risky, both in terms of its position in space and its unproven deployment method, some type of insurance policy may be needed to ensure NASA has a powerful telescope operating in space. But without Space Shuttles to visit the Hubble and extend its life, a different vehicle would have to be tasked with any potential future servicing missions. Enter the Dream Chaser Space System (DCSS).

The Dream Chaser Space System is like a smaller Space Shuttle. It can carry seven people into Low-Earth Orbit (LEO). Like the Shuttles, it then returns to Earth and lands horizontally on an airstrip. The DCSS, however, does not have a cargo bay or a robotic arm. If it were used for a Hubble repair mission, all repairs would likely have to be done during spacewalks. The DCSS is designed as a cargo and crew resupply ship for the International Space System. The much larger shuttles were designed with the Hubble in mind, as well as other tasks, like building and servicing the ISS and recovering satellites from orbit.

The DCSS is built by Sierra Nevada Corporation. It will be launched on an Atlas V rocket, and will return to Earth by gliding, where it can land on any commercial runway. The DCSS has its own reaction control system for manoeuvering in space. Like other commercial space ventures, the development of the DCSS has been partly funded by NASA.

The primary mirror of the James Webb Space Telescope is unfolded once it's in space. If it fails to deploy properly, NASA may need to use the Dream Chaser to keep the Hubble Telescope operating instead. Image: NASA/Chris Gunn — The primary mirror of the James Webb Space Telescope. Image: NASA/Chris Gunn

The James Webb has a complex deployment. It will be launched on an Ariane 5 rocket, where it will be folded up in order to fit. The primary mirror on the JWST is made up of 18 segments which must unfold in three sections for the telescope to function. The telescope’s sun shield, which keeps the JWST cool, must also unfold after being deployed. Earlier in the mission, the Webb’s solar array and antennae need to be deployed.

This video shows the deployment of the JWST. It reminds one of a giant insect going through metamorphosis.

If either the mirror, the sunshield, or any of the other unfolding mechanisms fail, then a costly and problematic mission will have to be planned to correct the deployment. If some other crucial part of the telescope fails, then it probably can’t be repaired. NASA needs everything to go well.

People have been waiting for the JWST for a long time. It’s had kind of a tortured path to get this far. We all have our fingers crossed that the mission succeeds. But if there are problems, it may be up to the Hubble to keep doing what it’s always done: provide the kinds of science and stunning images that excites scientists and the rest of us about the Universe.

February 14, 2017February 14, 2017 by Evan Gough

Chance Discovery Of A Three Hour Old Supernova

Artistic impression of a star going supernova, casting its chemically enriched contents into the universe. Credit: NASA/Swift/Skyworks Digital/Dana Berry

Supernovae are extremely energetic and dynamic events in the universe. The brightest one we’ve ever observed was discovered in 2015 and was as bright as 570 billion Suns. Their luminosity signifies their significance in the cosmos. They produce the heavy elements that make up people and planets, and their shockwaves trigger the formation of the next generation of stars.

There are about 3 supernovae every 100 hundred years in the Milky Way galaxy. Throughout human history, only a handful of supernovae have been observed. The earliest recorded supernova was observed by Chinese astronomers in 185 AD. The most famous supernova is probably SN 1054 (historic supernovae are named for the year they were observed) which created the Crab Nebula. Now, thanks to all of our telescopes and observatories, observing supernovae is fairly routine.

The supernova that produced the Crab Nebula was detected by naked-eye observers around the world in 1054 A.D. This composite image uses data from NASA’s Great Observatories, Chandra, Hubble, and Spitzer, to show that a superdense neutron star is energizing the expanding Nebula by spewing out magnetic fields and a blizzard of extremely high-energy particles. The Chandra X-ray image is shown in light blue, the Hubble Space Telescope optical images are in green and dark blue, and the Spitzer Space Telescope’s infrared image is in red. The size of the X-ray image is smaller than the others because ultrahigh-energy X-ray emitting electrons radiate away their energy more quickly than the lower-energy electrons emitting optical and infrared light. The neutron star is the bright white dot in the center of the image. — The supernova that produced the Crab Nebula was detected by naked-eye observers around the world in 1054 A.D. This composite image uses data from NASA’s Great Observatories, Chandra, Hubble, and Spitzer.

But one thing astronomers have never observed is the very early stages of a supernova. That changed in 2013 when, by chance, the automated Intermediate Palomar Transient Factory (IPTF) caught sight of a supernova only 3 hours old.

Spotting a supernovae in its first few hours is extremely important, because we can quickly point other ‘scopes at it and gather data about the SN’s progenitor star. In this case, according to a paper published at Nature Physics, follow-up observations revealed a surprise: SN 2013fs was surrounded by circumstellar material (CSM) that it ejected in the year prior to the supernova event. The CSM was ejected at a high rate of approximately 10 -³ solar masses per year. According to the paper, this kind of instability might be common among supernovae.

SN 2013fs was a red super-giant. Astronomers didn’t think that those types of stars ejected material prior to going supernova. But follow up observations with other telescopes showed the supernova explosion moving through a cloud of material previously ejected by a star. What this means for our understanding of supernovae isn’t clear yet, but it’s probably a game changer.

Catching the 3-hour-old SN 2013fs was an extremely lucky event. The IPTF is a fully-automated wide-field survey of the sky. It’s a system of 11 CCD’s installed on a telescope at the Palomar Observatory in California. It takes 60 second exposures at frequencies from 5 days apart to 90 seconds apart. This is what allowed it to capture SN 2013fs in its early stages.

The 48 inch telescope at the Palomar Observatory. The IPTF is installed on this telescope. Image: IPTF/Palomar Observatory

Our understanding of supernovae is a mixture of theory and observed data. We know a lot about how they collapse, why they collapse, and what types of supernovae there are. But this is our first data point of a SN in its early hours.

SN 2013fs is 160 million light years away in a spiral-arm galaxy called NGC7610. It’s a type II supernova, meaning that it’s at least 8 times as massive as our Sun, but not more than 50 times as massive. Type II supernovae are mostly observed in the spiral arms of galaxies.

A supernova is the end state of some of the stars in the universe. But not all stars. Only massive stars can become supernova. Our own Sun is much too small.

Stars are like dynamic balancing acts between two forces: fusion and gravity.

As hydrogen is fused into helium in the center of a star, it causes enormous outward pressure in the form of photons. That is what lights and warms our planet. But stars are, of course, enormously massive. And all that mass is subject to gravity, which pulls the star’s mass inward. So the fusion and the gravity more or less balance each other out. This is called stellar equilibrium, which is the state our Sun is in, and will be in for several billion more years.

But stars don’t last forever, or rather, their hydrogen doesn’t. And once the hydrogen runs out, the star begins to change. In the case of a massive star, it begins to fuse heavier and heavier elements, until it fuses iron and nickel in its core. The fusion of iron and nickel is a natural fusion limit in a star, and once it reaches the iron and nickel fusion stage, fusion stops. We now have a star with an inert core of iron and nickel.

Now that fusion has stopped, stellar equilibrium is broken, and the enormous gravitational pressure of the star’s mass causes a collapse. This rapid collapse causes the core to heat again, which halts the collapse and causes a massive outwards shockwave. The shockwave hits the outer stellar material and blasts it out into space. Voila, a supernova.

The extremely high temperatures of the shockwave have one more important effect. It heats the stellar material outside the core, though very briefly, which allows the fusion of elements heavier than iron. This explains why the extremely heavy elements like uranium are much rarer than lighter elements. Only large enough stars that go supernova can forge the heaviest elements.

In a nutshell, that is a type II supernova, the same type found in 2013 when it was only 3 hours old. How the discovery of the CSM ejected by SN 2013fs will grow our understanding of supernovae is not fully understood.

Supernovae are fairly well-understood events, but their are still many questions surrounding them. Whether these new observations of the very earliest stages of a supernovae will answer some of our questions, or just create more unanswered questions, remains to be seen.

February 14, 2017February 20, 2017 by Matt Williams

Distance & Speed Of Sun’s Orbit Around Galactic Centre Measured

Artist’s conception of the Gaia telescope backdropped by a photograph of the Milky Way taken at the European Southern Observatory. Credit: ESA/ATG medialab; background: ESO/S. Brunier

In 2013, the European Space Agency deployed the long-awaited Gaia space observatory. As one of a handful of next-generation space observatories that will be going up before the end of the decade, this mission has spent the past few years cataloging over a billion astronomical objects. Using this data, astronomers and astrophysicists hope to create the largest and most precise 3D map of the Milky Way to date.

Though it is almost to the end of its mission, much of its earliest information is still bearing fruit. For example, using the mission’s initial data release, a team of astrophysicists from the University of Toronto managed to calculate the speed at which the Sun orbits the Milky Way. From this, they were able to obtain a precise distance estimate between our Sun and the center of the galaxy for the first time.

For some time, astronomers have been unsure as to exactly how far our Solar System is from the center of our galaxy. Much of this has to do with the fact that it is impossible to view it directly, due to a combination of factors (i.e. perspective, the size of our galaxy, and visibility barriers). As a result, since the year 2000, official estimates have varied between 7.2 and 8.8 kiloparsecs (~23,483 to 28,700 light years).

Astronomy Image Gallery — *Infrared image from Spitzer Space Telescope, showing the stars at the center of the Milky Way Galaxy. Credit: NASA/JPL-Caltech/S. Stolovy (SSC/Caltech)*

For the sake of their study, the team – which was led by Jason Hunt, a Dunlap Fellow at the Dunlap Institute for Astronomy & Astrophysics at the University of Toronto – combined Gaia’s initial release with data from the RAdial Velocity Experiment (RAVE). This survey, which was conducted between 2003 and 2013 by the Australian Astronomical Observatory (AAO), measured the positions, distances, radial velocities and spectra of 500,000 stars.

Over 200,000 of these stars were also observed by Gaia and information on them was included in its initial data release. As they explain in their study, which was published in the Journal of Astrophysical Letters in November 2016, they used this to examined the speeds at which these stars orbit the center of the galaxy (relative to the Sun), and in the process discovered that there was an apparent distribution in their relative velocities.

In short, our Sun moves around the center of the Milky Way at a speed of 240 km/s (149 mi/s), or 864,000 km/h (536,865 mph). Naturally, some of the more than 200,000 candidates were moving faster or slower. But for some, there was no apparent angular momentum, which they attributed to these stars being scattering onto “chaotic, halo-type orbits when they pass through the Galactic nucleus”.

As Hunt explained in Dunlap Institute press release:

“Stars with very close to zero angular momentum would have plunged towards the Galactic center where they would be strongly affected by the extreme gravitational forces present there. This would scatter them into chaotic orbits taking them far above the Galactic plane and away from the Solar neighbourhood… By measuring the velocity with which nearby stars rotate around our Galaxy with respect to the Sun, we can observe a lack of stars with a specific negative relative velocity. And because we know this dip corresponds to 0 km/sec, it tells us, in turn, how fast we are moving.”

*Detection of an unusually bright X-Ray flare from Sagittarius A*, a supermassive black hole in the center of the Milky Way galaxy. Credit: NASA/CXC/Stanford/I. Zhuravleva et al.*

The next step was to combine this information with proper motion calculations of Sagittarius A* – the supermassive black hole believed to be at the center of our galaxy. After correcting for its motion relative to background objects, they were able to effectively triangulate the Earth’s distance from the center of the galaxy. From this, they derived a refined distance of estimate of 7.6 to 8.2 kpc – which works out to about 24,788 to 26,745 light years.

This study builds upon previous work conducted by the study’s co-authors – Prof. Ray Calberg, the current chair of the Department of Astronomy & Astrophysics at the University of Toronto. Years ago, he and Prof. Kimmo Innanen of the Department of Physics and Astronomy at York University conducted a similar study using radial velocity measurement from 400 of the Milky Way’s stars.

But by incorporating data from the Gaia observatory, the UofT team was able to obtain a much more comprehensive data set and narrow the distance to galactic center by a significant amount. And this was based on only the initial data released by the Gaia mission. Looking ahead, Hunt anticipates that further data releases will allow his team and other astronomers to refine their calculations even more.

“Gaia’s final release in late 2017 should enable us to increase the precision of our measurement of the Sun’s velocity to within approximately one km/sec,” he said, “which in turn will significantly increase the accuracy of our measurement of our distance from the Galactic center.”

As more next-generation space telescopes and observatories are deployed, we can expect them to provide us with a wealth of new information about our Universe. And from this, we can expect that astronomers and astrophysicists will begin to shine the light on a number of unresolved cosmological questions.

Further Reading: University of Toronto, The Astrophysical Journal Letters