Universe Today

February 8, 2012December 24, 2015 by Mike Simonsen

Hubble’s 1923 Nova in Andromeda Erupts Again!

M31N 1923-12c in Andromeda, position plotted by the AAVSO Chart Plotter

[/caption]

On December 11, 1923, Edwin Hubble discovered a nova in the Andromeda galaxy. Novae occurring in our Milky Way’s sister galaxy have proven to be not that uncommon, as there have been over 800 novae detected in M31 in the last 100 years. Hubble’s 1923 discovery became known as M31N 1923-12c, the third nova discovered in December of 1923.

Fast forward to January 21, 2012, and another nova has been discovered in M31, already the second novae seen in January 2012. K. Nishiyama and F. Kabashima reported the discovery and it has been given the designation, PNV J00423804+4108417. A day later, a spectrum was taken with the 9.2m Hobby-Eberly Telescope using the Marcario Low-Resolution Spectrograph, confirming the new nova in M31, and that it is a member of the He/N spectroscopic class.

What’s even more interesting, however, is that the new nova likely comes from the same progenitor as Hubble’s 1923 nova!

Artist's rendition of the recurrent nova RS Oph Credit: David Hardy/PPARC

Classical novae are a subclass of cataclysmic variable stars. They are semi-detached binary systems where an evolved, late-type star fills its Roche lobe and transfers mass to its white dwarf companion. If the mass accretion rate onto the white dwarf is sufficiently low, it allows this gas to pile up and become degenerate. Eventually, after thousands to tens of thousands of years, a thermonuclear runaway ensues in this highly pressurized layer of gas, leading to a nova eruption. These eruptions can reach an absolute magnitude as bright as about MV -10, making them among the most luminous explosions in the Universe. Their high luminosities and rates, about 50 per year in a galaxy like M31, make novae very useful to astronomers exploring the properties of close binaries in extragalactic stellar populations.

Comparing its position with the approximately 900 novae in W. Pietsch’s M31 nova catalog revealed that PNV J00423804+4108417 was located about six arc seconds from the cataloged position of M31N 1923-12c, the nova discovered by Edwin Hubble on December 11, 1923. Given that the positions of M31 novae from early photographic surveys were typically reported to a precision of only ten arc seconds, and that He/N spectra are often associated with recurrent novae, astronomers considered the possibility that M31N 1923-12c and PNV J00423804+4108417 represented two outbursts arising from the same nova progenitor. To explore this possibility further, F. Schweizer (Carnegie Observatories) located Hubble’s original plate in the Carnegie Observatories archives and performed an eyeball comparison of the position of Hubble’s nova with that of PNV J00423804+4108417, finding them to match within ~1.5″. You can see the images for yourself here.

After digitally scanning the Hubble plate and comparing the position of the nova relative to those of three nearby USNO reference stars, analysis revealed that M31N 1923-12c was located
at R.A. = 00 42 38.06; Decl. = 41 08 41.0 (J2000). Hubble’s M31N 1923-12c and this year’s PNV J00423804+4108417 are the same object!

88 years and a handful of days later, PNV J00423804+4108417 represents the second recorded outburst of the recurrent nova M31N 1923-12c. Like the telescope named for him, Hubble’s legacy to astronomy and astrophysics continues to grow to this very day. Way to go, Edwin.

This blog post adapted from Astronomer’s Telegram #3914
M31N 1923-12c is a recurrent nova in M31
Authors: A. W. Shafter (SDSU), M. J. Darnley, M. F. Bode (Liverpool JMU, UK), R. Ciardullo (PSU), F. Schweizer (Carnegie Observatories)

February 8, 2012December 24, 2015 by Nancy Atkinson

Most Detailed Look Ever Into the Carina Nebula

A broad panorama of the Carina Nebula, a region of massive star formation in the southern skies. This new method of determining the age of stars will help astronomers better understand the process of star formation. Credit: ESO/T. Preibisch

[/caption]

Like finding buried treasure, this new image of the Carina Nebula has uncovered details not seen before. This vibrant image, from ESO’s Very Large Telescope shows not just the brilliant massive stars, but uncovers hundreds of thousands of much fainter stars that were previously hidden from view. Hundreds of individual images have been combined to create this picture, which is the most detailed infrared mosaic of the nebula ever taken and one of the most dramatic images ever created by the VLT.

Although this nebula is spectacular when seen through telescopes, or in normal visible-light pictures, many of its secrets are hidden behind thick clouds of dust. Using HAWK-I infrared camera along with the VLT, many previously hidden features have emerged from the murk. One of the main goals of the astronomers, led by Thomas Preibisch from the University Observatory, Munich, Germany, was to search for stars in this region that were much fainter and less massive than the Sun. The image is also deep enough to allow the detection of young brown dwarfs.

The dazzling but unstable star Eta Carinae appears at the lower left of the new picture. This star is likely to explode as a supernova in the near future, by astronomical standards. It is surrounded by clouds of gas that are glowing under the onslaught of fierce ultraviolet radiation. Across the image there are also many compact blobs of dark material that remain opaque even in the infrared. These are the dusty cocoons in which new stars are forming.

The Carina Nebula lies about 7,500 light-years from Earth in the constellation of Carina.

This video zooms in on the new infrared view of the Carina Nebula:

Loading player…

Source: ESO

February 8, 2012December 24, 2015 by Jason Major

Special Delivery, Low-Earth Orbit Style!

A Progress resupply vehicle seen on approach to the ISS on Jan. 27, 2012. (NASA)

[/caption]

When you’re cruising along in low-Earth orbit, running out of supplies is not an option. Fortunately there are Progress vehicles: Russian spacecraft that carry much-needed supplies and equipment to the astronauts aboard the Space Station.

The photo above, taken by Expedition 30 crew members, shows the unmanned Progress 46 vehicle approaching the ISS on January 27, 2012.

Progress 46 carried 2,050 pounds of propellant, 110 pounds oxygen and air, 926 pounds of water and 2,778 pounds of parts and experiment hardware, for a total of 2.9 tons of food, fuel and equipment for the Expedition 30 crew.

The Progress is similar in appearance and design to Soyuz spacecraft, which serve as human transportation to and from the Space Station, but differs in that the second of the spacecraft’s three sections (as prior to launch) is a refueling module, and the third uppermost section is a cargo module.

In addition to bringing supplies to the ISS, Progress vehicles also serve as – for lack of a better term – “garbage trucks”, undocking from the Station loaded with trash and re-entering the atmosphere, during which time much of the refuse inside gets incinerated.

Progress 46 successfully docked to the Space Station at 7:09 p.m. (EST) on Jan. 27, 2012.

Image: NASA

February 8, 2012December 24, 2015 by Ken Kremer

China Unveils High Resolution Global Moon Map

China Publishes High Resolution Full Moon map from Chang'e-2 Lunar Orbiter. Chinese scientists assembled a full moon map using images captured by the Chang’e-2 spacecraft with an an unprecedented resolution of 7-meters. Credit: China Space Program

[/caption]

Chinese scientists have assembled the highest resolution map ever created of the entire Moon and unveiled a series of global Moon images on Monday, Feb. 6.

The composite Lunar maps were created from over 700 individual images captured by China’s Chang’e-2 spacecraft and released by the country’s State Administration of Science, Technology and Industry for National Defence (SASTIND), according to reports from the state run Xinhua and CCTV new agencies.

“The map and images are the highest-resolution photos of the entirety of the Moon’s surface to be published thus far,” said Liu Dongkui, deputy chief commander of China’s lunar probe project, reports Xinhua.

Of course there are much higher resolution photos of numerous individual locations on the Moon taken from orbit by the spacecraft of other countries and from the surface by NASA’s Apollo lunar landing astronauts as well as unmanned Russian & American lunar landers and rovers.

China unveils High Resolution Global Moon map from Chang'e-2 Lunar Orbiter
Credit: China Space Program

Chang’e-2 is China’s second lunar probe and achieved orbit around our nearest neighbor in space in October 2010. It was launched on Oct. 1, 2010 and is named after a legendary Chinese moon goddess.

The images were snapped between October 2010 and May 2011 using a charge-coupled device (CCD) stereo camera as the spacecraft flew overhead in a highly elliptical orbit ranging from 15 km to 100 km altitude.

The Chang’e-2 maps have a resolution of 7 meters, which is 17 times greater than from China’s first lunar orbiter; Chang’e-1, launched in 2007.

Global Lunar Map from China’s Chang'e-2 Lunar Orbiter. Credit: China Space Program

In fact the maps are detailed enough that Chinese scientists were able to detect traces of the Apollo landers, said Yan Jun, chief application scientist for China’s lunar exploration project.

Chang’e-2 also captured high resolution photos of the “Sinus Iridum”area , or Bay of Rainbows, where China may land their next Moon mission. The camera had the ability to resolve features as small as 1 meter across at the lowest altitude.

The satellite left lunar orbit in June 2011 and is currently orbiting the moon’s second Lagrange Point (L2), located more than 1.5 million km away from Earth.

Chinese space program officials hope for a 2013 liftoff of the Chang’e-3 lunar rover, on what would be China’s first ever landing on another celestial body. China’s next step beyond the rover may be to attempt a lunar sample return mission in 2017.

Demonstrating the ability to successfully conduct an unmanned lunar landing is a key milestone that must be achieved before China can land astronauts on the Moon, perhaps within the next decade.

NASA’s twin GRAIL spacecraft recently achieved Lunar orbit over the New Year’s weekend. The duo of probes were just renamed as “Ebb and Flow” – the winning entries in an essay naming contest submitted by 4th Grade US students from Bozeman, Montana.

At this time NASA does not have the funding or an approved robotic lunar landing mission, due to severe budget cuts.And even worse NASA cuts will be announced shortly !

Russia hopes to send the Lunar Glob spacecraft to land on the Moon around 2015.

Since the United States has unilaterally scuttled its plans to return American astronauts to the Moon’s surface, it’s very possible that the next flag planted on the Moon by humans will be Chinese.

February 8, 2012December 24, 2015 by Nancy Atkinson

A Bouncing Moon Boulder

A large boulder stopped on its way down a sloping wall in the central peak of Schiller crater on the Moon. Credit: NASA/GSFC/Arizona State University.

[/caption]

One solitary boulder on the Moon apparently decided to take a little journey. The Lunar Reconnaissance Orbiter Camera captured the track of a bouncing, rolling 9-meter boulder that used to sit along the rim of a crater. From the pristine nature of the tracks, it might seem that the rock may have taken its trip just recently. But with the high resolution capability of the LROC, scientists can see that a few tiny craters are superimposed among the track and therefore post-date the time the boulder traveled. Scientists estimate this track was created 50-100 million years ago.

“Though long ago to humans, however, this boulder’s journey was made in geologically recent times,” wrote lunar scientist James Ashley on the LROC website. “Studies suggest that regolith development from micrometeorite impacts will erase tracks like these over time intervals of tens of millions of years…Eventually its track will be erased completely.”

What might have caused the rock to roll so recently? Ashley said perhaps this boulder was sent on its way by ground-shaking caused by the violence of a nearby impact. Perhaps a direct hit by a small meteoroid did the job.

This isn’t the first time LRO has captured evidence of “moving” rocks. See our previous article about several other images of bouncing boulders.

Source: LROC

February 7, 2012April 26, 2016 by Nancy Atkinson

NASA Looking for More Space Taxis

Image: Artist concept of Sierra Nevada’s Dream Chaser docked to the ISS. Credit: Sierra Nevada

[/caption]

NASA is looking for more ways to get astronauts to the International Space Station. The space agency put out a call today for commercial space companies to submit bids as part of the latest round of the Commercial Crew Program, now called Commercial Crew Integrated Capability (CCICap). NASA plans to select at least two potential providers for “safe, reliable, and cost effective human access to space” and they expects to make multiple awards this summer, with values ranging from $300 – $500 million. Those winning the bids will need to develop an integrated system that includes both a crew vehicle and launch system, with work to be completed May 31, 2014.

NASA currently relies on Russian Soyuz vehicles to bring crews to the station, at a cost of $63 million per seat. The Soyuz has experienced unprecedented recent problems with both the Soyuz rocket and now a delay in the next two Soyuz flights to the ISS due to a leak of the capsule during testing.

NASA’s Commercial Crew Program manager Ed Mango spoke at a forum this morning, prior to NASA’s official CCICap announcement and said the hopes are that an initial crewed demonstration flight to low Earth orbit will take place in 2015-2016, with regular commercially operated flights to the ISS beginning around 2017.

The projected timing and funding all hinges on whether Congress approves NASA’s budget request; Legislators provided $406 million for Commercial Crew in 2012, less than half of what the agency requested.

“President Obama is working hard to create an American economy built to last,” NASA Administrator Charles Bolden said in a NASA press releases. “NASA’s support of commercial innovation to reach low Earth orbit is helping to support these efforts by spurring new technological development and creating jobs and economic benefits for years to come.”

The companies will also need to provide ground operations and mission control, and to meet certain milestones in the development in of a crewed orbital demonstration flight.

Current companies receiving funds from NASA for commercial crew are Boeing, Sierra Nevada, SpaceX, and Blue Origin. Companies have until March 23, 2012 to submit their proposals.

Sources: NASA, Space News

February 7, 2012December 24, 2015 by Nancy Atkinson

GALEX Mission Comes to an End

The GALEX spacecraft before its launch in 2003. Credit: JPL

[/caption]

A mission which helped map the ultraviolet sky and worked to confirm the nature of dark energy is coming to an end. Galaxy Evolution Explorer, or GALEX, was placed in standby mode today after nearly nine years of service and will be decommissioned later this year. With data from the mission, scientists were able to catalog millions of galaxies spanning 10 billion years of cosmic time.

The Galaxy Evolution Explorer launched in April of 2003 on board a Pegasus XL rocket. It completed its prime mission in the fall of 2007, but the mission was extended to continue its census of stars and galaxies.

The variable star Mira with a comet-like tail. Image credit: Galex — The variable star Mira. Image credit: Galex

Other mission highlights include the discovery of a gigantic comet-like tail behind a speeding star, finding rings of new stars around old galaxies, exploring “teenager” galaxies, which help to explain how galaxies evolve, and catching a black hole devouring a star.
The mission was part of NASA’s Explorer’s program and was built and managed by the Jet Propulsion Laboratory. Scientists from around the world participated in GALEX studies.

For a complete list of discoveries by GALEX, see this JPL webpage.

February 7, 2012December 24, 2015 by Tammy Plotner

Requiem For Astronaut Janice Voss

Dr. Janice Voss - Photo Courtesy of NASA

[/caption]

Please take the time to respectfully recognize the passing of veteran astronaut, Janice Voss. She was a former science director for a NASA exoplanet-hunting spacecraft and also a member of five manned spaceflights. She lost her battle with cancer today at the young age of 55. “Just got the very sad news that U.S. astronaut Janice Voss passed away last night,” the Association of Space Explorers, an international organization representing more than 350 individuals who have flown in space, wrote on Facebook. “Our thoughts go out to her family and friends.” NASA confirmed Voss’ passing in a statement issued on Tuesday (Feb. 7), saying she had passed away overnight.

Janice was born on October 8, 1956, in South Bend, Indiana, but she called Rockford, Illinois home. Some of her passions for life included flying, volleyball, dancing and reading science fiction. She graduated from from Minnechaug Regional High School, Wilbraham, Massachusetts, in 1972, continued on to Purdue University for her bachelor of science degree and achieved a master of science degree in electrical engineering and a doctorate in aeronautics/astronautics from the Massachusetts Institute of Technology in 1977 and 1987, respectively. From there, Janice continued her education by taking some correspondence courses from the University of Oklahoma and did some graduate work in space physics at Rice University in 1977 and 1978.

JaniceVoss2 — Astronaut Janice Voss pictured in 2000 on the flight deck of the space shuttle Endeavour during the STS-99 mission. (NASA)

In 1990, Janice Voss was chosen by NASA for the astronaut corps and served as a mission specialist on five space shuttle missions, including the only repeat flight in the program’s 30 year history. But that’s not all. She also flew with the first commercial lab, rendezvoused with Russia’s Mir space station and helped create the most complete digital topographic map of the Earth. In June 1993, Janice took part in biomedical and material science experiments as a member of the Spacehab module – a commercial laboratory attached to the orbiter’s payload bay. In February 2000, Voss again launched on Endeavour as part of the Shuttle Radar Topography Mission crew. After deploying a nearly 200-foot (60-meter) mast, Voss and her team labored through two full shifts to map more than 47 million square miles (122 million square kilometers) of the Earth’s land surface. The shuttle Endeavour served as both her first and final mission.

The first time a space shuttle came close to the Russian Space Station, Mir, Dr. Voss was there. As her second mission, she and her STS-63 crew mates met with the Russians to discuss flight techniques, communications, sensors aids and navigation. The February 1995 “Near-Mir” mission set the stage for the first shuttle-Mir docking later that year. Janice also served on another historic mission – the only time a crew was launched twice to perform the same mission. The first launch came on April 4, 1997 and three days later it returned to Earth after a fuel cell problem. Ninty days later, the Columbia was restored and it launched again into a successful 15 day flight. This time Voss and crew engaged their time inside a European Spacelab module, conducting experiments as part of the Microgravity Science Laboratory (MSL) mission.

JaniceVoss3 — Janice Voss, shown in April 1997 working with communications systems on the aft flight deck of space shuttle Columbia. (NASA)

Over her career, astronaut Janice Voss totaled over 49 days in space, traveling 18.8 million miles (30.3 million km) while circling the Earth 779 times. Her five missions tied her with the record for the most spaceflights by a woman. When she at last touched down on Earth, she went on to the Johnson Space Center in Houston, Texas to NASA’s Ames Research Center at Moffett Field, California, where she headed the science program for the agency’s Kepler space observatory. She stayed at Ames until 2007 and spent the rest of her time as the payload lead in the astronaut office’s space station branch at the Johnson Space Center.

JaniceVoss4 — Janice Voss, pictured looking over a checklist on space shuttle Endeavour's aft flight deck during her final spaceflight. (NASA)

“As payload commander of two shuttle missions, Janice was responsible for paving the way for experiments that we now perform on a daily basis on the International Space Station,” chief astronaut Peggy Whitson said in a statement. “By improving the way scientists are able to analyze their data, and establishing the experimental methods and hardware necessary to perform these unique experiments, Janice and her crew ensured that our space station would be the site of discoveries that we haven’t even imagined.”

“During the last few years, Janice continued to lead our office’s efforts to provide the best possible procedures to crews operating experiments on the station today,” she said. “Even more than Janice’s professional contributions, we will miss her positive outlook on the world and her determination to make all things better.”

Godspeed, Janice… Godspeed.

Original Story Source: CollectSpace News and NASA Files.

February 7, 2012December 24, 2015 by Paul Scott Anderson

When Stars Play Planetary Pinball

Artist's conception of a binary star sunset seen from the planet Kepler-16b. Credit: NASA/Ames Research Center/Kepler Mission

[/caption]

Many of us remember playing pinball at the local arcade while growing up; it turns out that some stars like it as well. Binary stars can play tug-of-war with an unfortunate planet, flinging it into a wide orbit that allows it to be captured by first one star and then the other, in effect “bouncing” it between them before it is eventually flung out into deep space.

The new paper, by Nick Moeckel and Dimitri Veras of the University of Cambridge, will be published in a future issue of Monthly Notices of the Royal Astronomical Society.

The gravitational pull of large gas giant planets can affect the orbits of smaller planets; that scenario is thought to have occurred in our own solar system. In some cases, the smaller planet may be flung into a much wider orbit, perhaps even 100 times wider than Pluto’s. In the case of single stars, that’s normally how it ends. In a binary star system, however, the two stars may play a game of “cosmic pinball” with the poor planet first.

Moeckel and Dimitri conducted simulations of binary star systems, with two sun-like stars orbiting each other at distances between 250 and 1,000 times the distance of the Earth from the Sun. Each star had its own set of planets. The planetary systems would often become unstable, resulting in one of the planets being flung out, where it could be subsequently captured by the other star’s gravity. Since the new orbit around the second star would also tend to be quite wide, the planet would be vulnerable to recapture again by the first star. This could continue for a long time, and the simulations indicated that more than half of all planets initially ejected would get caught in this game of “cosmic pinball.”

In the end, some planets would settle back into an orbit around one of the stars, but the majority would escape both stars altogether, finally being flung out into deep space forever.

According to Moeckel, “Once a planet starts transitioning back and forth, it’s almost certainly at the beginning of a trip that will end in deep space.”

We are fortunate to live in a solar system where our planet is in a nice, stable orbit. For others out there who may not be so lucky, it would be like living through a disaster movie played out over eons.

The paper is available here.

February 7, 2012December 24, 2015 by Nancy Atkinson

Can you See the Pyramids from Space?

Click for a larger version of this image to see if you can see the Pyramids at Giza from the International Space Station. Via astronaut Nicole Stott's Twitpic feed.

[/caption]

Astronaut Nicole Stott posted this image on her Twitter account. If you can spot the Great Pyramids at Giza in this small image, you’ve pretty good eyesight! Click the image for a larger version if can’t find them.

Astronaut Soichi Noguchi posted an image of different set of pyramids at Dahshur, Egypt, from his stint on the ISS in 2010. He zoomed in a little more, making them easier to see, below:

72243995 — The Red Pyramid and the Bent Pyramid in Dahshur, Egypt. Credit: Soichi Noguchi/NASA/JAXA

But there’s still the question, can you see the Great Wall of China from space?