The search for planets orbiting other stars is still on, 15 years after the first one was found.
It is extremely hard to determine which ones could support life and which stars can support
life. A recent article here, http://news.discovery.com/space/red-dwarfs-may-be-safe-havens-for-life.html
is worth a quick read about how life on planets orbit red dwarf stars might be possible.
Archive for the ‘Astronomy’ Category
Can a Red Dwarf Support Life?
Saturday, July 24th, 2010Sun’s Rumored Dwarf Companion May Not be Exist
Saturday, July 24th, 2010Some astronomers have hypothesized that a companion star that circles our sun that causes extinctions in the solar system may not exist. The idea was first proposed in 1984 to explain perplexing cycles in mass extinctions on Earth. About every 27 million years, almost like clockwork, there is a significantly higher likelihood that a mass extinction will take place on our planet (like an apocalypse that killed off the dinosaurs) about 65.5 million years ago.
The regular cycle of millions of years has been very troubling and confusing, and an element in our solar system causing the problem seems reasonable. The galaxy takes about 250 million years to orbit the center.
An ultra low-mass star such as a red or white dwarf might orbiting at a large distance, possibly a light year away. It would theoretically take 27 million years to finish an orbit. At that rate, once during each orbit it may enter a collection of comets surrounding the solar system called the Oort cloud. When the star passes through the Oort cloud, it could disturb the orbits of many comets, causing a shower of comets on Earth at such an extreme rate to cause such events.
A new study has confirmed that the 27-million-year cycle exists, with an excess of extinctions happening around those peaks. There are extinctions that occur in the middle of a cycle, and sometimes when a peak comes around the Earth has been safe. But, scientists confirmed that life gets a riskier here every 27 million years.
View of Oil Spill From Space!
Tuesday, June 29th, 2010This is a video that shows NASA satellite imagery over a period of time of the oil spill.
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Credit: NASA/Goddard/Jen Shoemaker |
Two NASA satellites are capturing images of the oil spill in the Gulf of Mexico, which began April 20, 2010, with the explosion of the Deepwater Horizon oil rig. This series of images reveals a space-based view of the burning oil rig and the ensuing oil spill, through May 24. The imagery comes from the MODIS instruments aboard NASA’s Terra and Aqua satellites. The oil slick appears grayish-beige in these images. The shape of the spill changes due to weather conditions, currents and the use of oil-dispersing chemicals. The images in this video were selected to show the spill most clearly. The full image archive is available at http://rapidfire.sci.gsfc.nasa.gov.
Plus, Oil Spill at the Mouth of the Mississippi River!

Oil from the Deepwater Horizon spill laps around the mouth of the Mississippi River delta in this May 24, 2010, image from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA’s Terra spacecraft.  Ribbons and patches of oil that have leaked from the Deepwater Horizon well offshore appear silver against the light blue color of the adjacent water. Vegetation is red.  Image credit: Jesse Allen/NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team.
Seventh Graders Find a Cave on Mars
Tuesday, June 29th, 2010Using the camera on NASA’s Mars Odyssey orbiter, 16 seventh-graders at Evergreen Middle School in Cottonwood, Calif., found lava tubes with one pit that appears to be a skylight to a cave. Mars Odyssey has been orbiting the Red Planet since 2001, returning data and images of the Martian surface and providing relay communications service for Mars Rovers Spirit and Opportunity.
The students in Dennis Mitchell’s science class were examining Martian lava tubes as their project in the Mars Student Imaging Program offered by NASA and Arizona State University. According to the university, the imaging program allows students in upper elementary grades through to college students to participate in Mars research by having them develop a geological question to answer. The students actually command a Mars-orbiting camera to take an image to answer their question. Since MSIP began in 2004, more than 50,000 students have participated.
“The students developed a research project focused on finding the most common locations of lava tubes on Mars,” Mitchell said. “Do they occur most often near the summit of a volcano, on its flanks or the plains surrounding it?”
The feature, on the slope of an equatorial volcano named Pavonis Mons, appears to be a skylight in an underground lava tube. Similar ‘cave skylight’ features have been found elsewhere on Mars, but this is the first seen on this volcano.
The students subsequently submitted the site as a candidate for imaging by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter. HiRISE can image the surface at about 30 centimeters (12 inches) per pixel, which may allow a look inside the hole in the ground.
“It gives the students a good understanding of the way research is conducted and how that research can be important for the scientific community. This has been a wonderful experience,” Mitchell said.”

Sixteen seventh-graders at Evergreen Middle School in Cottonwood, Calif., found the Martian pit feature at the center of the superimposed red square in this image. Image Credit: NASA/JPL-Caltech/ASU
Ten Cool Things Seen in the First Year of LRO
Tuesday, June 29th, 2010Having officially reached lunar orbit on June 23rd, 2009, the Lunar Reconnaissance Orbiter (LRO) has now marked one full year on its mission to scout the moon. Maps and datasets collected by LRO’s state-of-the-art instruments will form the foundation for all future lunar exploration plans, as well as be critical to scientists working to better understand the moon and its environment. In only the first year of the mission, LRO has gathered more digital information than any previous planetary mission in history. To celebrate one year in orbit, here are ten cool things already observed by LRO. Note that the stories here are just a small sample of what the LRO team has released and barely touch on the major scientific accomplishments of the mission. If you like these, visit the official LRO web site at www.nasa.gov/LRO to find out even more!
The Coldest Place in the Solar System
One of LRO’’s observations from the past year goes beyond cool to absolutely frigid. Diviner, LRO’s temperature instrument, found a place in the floor of the moon’s Hermite Crater that was detected to be -415 degrees Fahrenheit (-248 Celsius) making it the coldest temperature measured anywhere in the solar system. For comparison, scientists believe that Pluto’s surface only gets down to about -300 degrees Fahrenheit (-184 Celsius). Extremely cold regions similar to the one in Hermite Crater were found at the bottoms of several permanently shaded craters at the lunar south pole and were measured in the depths of winter night. Image Credit: NASA/Goddard/University of California, Los Angeles
Astronauts’ First Steps on the Moon
On July 20, 1969, NASA added a page to the history books when Apollo 11 astronauts Neil Armstrong and Buzz Aldrin were the first humans to set foot on the moon. Though their stay was only brief, Armstrong and Aldrin had about two and a half hours to track around outside the module, taking pictures and deploying a few science experiments before returning to orbit and ultimately, the safety of Earth. Images of the Apollo 11 landing site from LRO clearly show where the descent stage (about 12 feet in diameter) was left behind as well as the astronauts’ tracks and the various equipment they deployed. This LRO data has important scientific value, as it provides context for the returned Apollo samples. Beyond their use for science, the images of all six manned landing sites observed by LRO provide a reminder of NASA’s proud legacy of exploration and a note of inspiration about what humans are capable of in the future. Image Credit: NASA/Goddard/Arizona State University
The Apollo 14 Near Miss of Cone Crater
While all of the Apollo missions are fascinating, the Apollo 14 activities provided a particularly interesting story to see in the images from LRO. The mission called for Alan Shepard and Edgar Mitchell to go to Fra Maura where they would attempt to gather samples from the rim of Cone Crater. Without having the aid of the lunar rover and having to drag a cart full of scientific equipment along with them, the trek from the descent module to Cone Crater proved to be a physically intense one. After traversing nearly a mile (1400 meters), the steep incline of the crater rim, the high heart rates of the astronauts and the tight schedule of the activity resulted in mission control ordering them to gather whatever samples they could and return to the landing module. They never reached the edge of the crater. Though geologists say it did not greatly affect the success of the scientific goal, the astronauts were personally disappointed in failing to make it to the top. Images from LRO now show precisely just how far the astronauts traveled and how close they came to reaching the crater, their tracks ending only about 100 feet (30 meters) from the rim! Image Credit: NASA/Goddard/Arizona State University
A Lost Russian Rover is Found
Lunokhod 1 was the name of a Russian robotic rover that landed on the moon in 1970 and navigated about 6 miles (10 km) of the lunar surface over 10 months before it lost contact in September 1971. Scientists were unsure of the rover’s whereabouts, though at least one team of researchers were searching for it, hoping to bounce a laser off of its retroreflector mirrors. This past March however, the LROC team announced they had spotted it, miles from the location the laser team had been searching. Using the info provided by LRO, a laser pulse was sent to Lunokhod 1 and contact was made with the rover for the first time in nearly four decades. Not only did Lunokhod 1’s retroreflector return a signal, but it returned one that was about five times better than those that have routinely been returned by Lunokhod 2’s mirrors over the years. Image Credit: NASA/Goddard/Arizona State University
The Lunar Far Side: The Side Never Seen from Earth
Tidal forces between the moon and the Earth have slowed the moon’ rotation so that one side of the moon always faces toward our planet. Though sometimes improperly referred to as the “dark side of the moon,” it should correctly be referred to as the “far side of the moon” since it receives just as much sunlight as the side that faces us. The dark side of the moon should refer to whatever hemisphere isn’t lit at a given time. Though several spacecraft have imaged the far side of the moon since then, LRO is providing new details about the entire half of the moon that is obscured from Earth. The lunar far side is rougher and has many more craters than the near side, so quite a few of the most fascinating lunar features are located there, including one of the largest known impact craters in the solar system, the South Pole-Aitken Basin. The image highlighted here shows the moon’s topography from LRO’s LOLA instruments with the highest elevations up above 20,000 feet in red and the lowest areas down below -20,000 feet in blue. Image Credit: NASA/Goddard
Counting Craters and Boulders
The LRO Camera (LROC) has a resolution about ten times better than any previous lunar orbiter missions. That means for every pixel imaged by other spacecraft, LROC gathers 100 pixels in that same area, enough to distinguish details never before possible. One of the most striking ways this manifests itself is in the ability to make out detailed craters and individual boulders, some no larger than a few feet on the lunar surface. In order to understand the history of the lunar surface and its features and mechanisms, scientists look at the abundance, size, shape, and distribution of both craters and boulders. By comparing and analyzing these feature counts across different regions as well as other places like the Earth and Mars, we can gain a better understanding of our solar system’s natural history. With the increased resolution of the LRO Camera as well as the new information gathered by LRO’s other instruments, scientists can characterize the moon’s surface in ways never before possible. This information will be critical for both science and future exploration plans. Not only that, but now thanks to the “Moon Zoo” (http://www.moonzoo.org) the public can get involved doing their own crater and boulder counts to aid in the research. With hundreds of gigabytes of new data returning daily, the contribution of “citizen scientists” can play a crucial part in lunar science. Image Credit: NASA/Goddard/Arizona State University
Mountains on the Moon
On the Earth, we are taught that mountains form over millions of years, the result of gradual shifting and colliding plates. On the moon however, the situation is quite different. Even the largest lunar mountains were formed in minutes or less as asteroids and comets slammed into the surface at tremendous velocities, displacing and uplifting enough crust to create peaks that easily rival those found on Earth. On a few occasions in the past year, NASA has tilted the angle of LRO to do calibrations and other tests. In such cases the camera has the opportunity to gather oblique images of the lunar surface like the one featured here of Cabeus Crater providing a dramatic view of the moon’s mountainous terrain. Cabeus Crater is located near the lunar south pole and contains the site of the LCROSS mission’s impact. Early measurements by several instruments on LRO were used to guide the decision to send LCROSS to Cabeus. During the LCROSS impact LRO was carefully positioned to observe both the gas cloud generated in the impact, as well as the heating at the impact site. Image Credit: NASA/Goddard/Arizona State University
Lunar Rilles: Mysterious Channels on the Moon
Rilles are long, narrow depressions on the lunar surface that look like river channels. Some are straight, some curve, and others, like the ones highlighted here, are called “sinuous” rilles and have strong meanders that twist and turn across the moon. Rilles are especially visible in radar imagery, like that gathered by LRO’s Mini-RF instrument. The formation of lunar rilles is not well understood. It is believed there may be many different formation mechanisms including ancient magma flows and the collapse of subterranean lava tubes. Imagery from LRO will help researchers to better understand these mysterious “river-like” lunar features. Image Credit: NASA/JHUAPL/LSI
Lunar Pits
LRO has now collected the most detailed images yet of at least two lunar pits, quite literally giant holes in the moon. Scientists believe these holes are actually skylights that form when the ceiling of a subterranean lava tube collapses, possibly due to a meteorite impact punching its way through. One of these skylights, the Marius Hills pit, was observed multiple times by the Japanese SELENE/Kaguya research team. With a diameter of about 213 feet (65 meters) and an estimated depth of 260 to 290 feet (80 to 88 meters) it’s a pit big enough to fit the White House completely inside. The image featured here is the Mare Ingenii pit. This hole is almost twice the size of the one in the Marius Hills and most surprisingly is found in an area with relatively few volcanic features. Image Credit: NASA/Goddard/Arizona State University
Areas of Near Constant Sunlight at the South Pole
One of the most vital resources LRO is searching for on the moon is solar illumination. Light from the sun provides both warmth and a source of energy, two critical constraints to exploration efforts. The moon’s axis is only slightly tilted so there are areas in high elevations at its poles that remain almost constantly exposed to the sun. Using LRO’s precise measurements of topography scientists have been able to map illumination in detail, finding some areas with up to 96% solar visibility. Such sites would have continuous sun for approximately 243 days a year and never have a period of total darkness for more than 24 hours. Image Credit: NASA/Goddard
Japanese Space Capsule Landing In South Australia
Sunday, June 13th, 2010Scientists from the Japanese Aerospace Exploration Agency (JAXA) and from NASA and the ANU are in Woomera to recover the capsule which they hope will provide important scientific clues about the composition of the asteroid, Itokawa. The spacecraft was launched by the Japanese Aerospace Exploration Agency (JAXA) in May 2003 and landed on the asteroid in November 2005. If successful, it will be the first time that a spacecraft has landed on an asteroid and returned to Earth.
Updates on the mission can be found here: http://www.jaxa.jp/press/2010/06/20100612_hayabusa_e.html
Obama’s Plan for NASA
Thursday, May 6th, 2010Three weeks after Obama told an audience at Kennedy Space Center that he wants to land astronauts on an asteroid by 2025, Congress, NASA, and the American public remains unconvinced. Under the Bush administration, NASA was scheduled to return to the moon to test new equipment before going to Mars. After canceling the space shuttle and new rocket designs, the Obama administration has decided to go for somewhat different goals: An Asteroid. Recently, the administration called for the cancellation of the constellation program, which would have wasted billions of dollars of tax player money. The government has famously canceled multi-billion dollar research projects more than three quarters completed, including a nuclear power plant that would have trans-mutated nuclear waste into usable fuel.
The moon has been visited, but why not anymore? The new goal appears to be an asteroid that is orbiting earth. (Remember the movie Armageddon?) The update of plan comes with a push for private industries to compete for contracts. Â The space capsule, a part of the Ares rocket program, would now be used as an emergency escape module for the International Space Station. Â After an asteroid, landing people in Mars will become a priority.
So much for the George W. Bush administration’s goal to visit the moon and build a permanent lunar base there.
The most controversial part of the president’s policy is the cancellation of the Constellation program, which was aimed at developing a new generation of Ares rockets and Orion spacecraft to send astronauts into Earth orbit and beyond. NASA itself also appears to be hedging its bets that the president’s vision might not pass muster with Congress. KSC officials and contractors, under direction from Johnson Space Center and NASA Administrator Charlie Bolden, are pressing ahead with plans for test flights of a multibillion-dollar Ares I rocket that Obama wants to cancel.
UGPSJ0722-05
Tuesday, April 13th, 2010Philip Lucas at the University of Hertfordshire, UK, and his international team are part of the UKIDSS Galactic Plane Survey, a program that uses the UK Infrared Telescope (UKIRT) in Hawaii to hunt for objects that glow in infrared, have spotted a brown dwarf 10 light-years from Earth. This makes it the nearest brown dwarf and one of ten nearest stellar objects to our solar system. It’s chemical composition of its atmosphere is a bit of a conundrum. UGPSJ0722-05 is  floating through interstellar space all by itself.
Brown dwarfs are sub-stellar objects which are too low in mass to sustain stable hydrogen fusion. Their mass is below that necessary to maintain hydrogen-burning nuclear fusion reactions in their cores, as do stars on the main sequence, but which have fully convective surfaces and interiors, with no chemical differentiation by depth. Brown dwarfs occupy the mass range between that of large gas giant planets and the lowest mass star. They emit in infrared, radiation the UKIDSS survey is sensitive to.
The UKIRT has already detected many cool brown dwarfs, but UGPSJ0722-05 appears to be the coolest ever discovered. It could have a surface temperature as low as 400 Kelvin, even cooler than the team’s previous record of slightly below 500 K.
Using the Gemini Observatory, follow-up spectroscopic analysis has detected methane and water vapor in its atmosphere. The presence of organic compounds is an extremely hot topic.
Interestingly, when looking at the spectrum from UGPSJ0722-05, there is an anomalous absorption line that cannot be explained by our current knowledge of brown dwarfs. This could be a new breed of brown dwarf or very cool object with some chemical in its atmosphere that absorbs infrared radiation at a wavelength of 1.25 micrometers.
Epsilon Aurigae Eclipse Mystery Solved
Monday, April 12th, 2010Epsilon Aurigae is located 2,000 light years from Earth in the northern constellation Auriga. It is one of the brightest stars but since the 1820s its light is halved in intensity for 18 months. It occurs once every 27.1 years.
Recently, the mystery surrounding the ‘eclipse’ has been solved, according to high-resolution images published in the journal Nature, points to a thin, dark and dense disk of dust that passes edge-on in front of the star, filtering out some of the light that reaches us. The dense disk of dust is thought to be a rare phase of stellar life, the building blocks of planets, and there is no other star system like this known.
Telescope Riding In a Boeing 747 Sees More Than Hubble
Wednesday, March 3rd, 2010On Dec. 18, NASA for the first time opened the doors of its Stratospheric Observatory for Infrared Astronomy in flight. Test fligthts occured since 2007. The telescope is built into the tail end of a Boeing 747. The overall mission is named the Stratospheric Observatory for Infrared Astronomy (SOFIA) and flies above atmospheric water vapor that blocks most infrared light from ground observatories. The telescope is easier to maintain than the Spitzer or Hubble and costs significantly less. IT scans the widest range of light of any scope, from ultraviolet to the far infrared.


