Tag: astronomy

The supernovae that fertilized the Earth

5:45 pm

A new study has pinned down the dates of two recent supernovae that showered the Earth with the heavier elements that make life here possible.

Many mainstream articles about this story have been implying that this research has discovered the existence of supernovae near the primordial Earth. This is false. Scientists have had evidence of these early supernovae for decades, from asteroids, in isotopes on Earth, and in the existence of the Local Bubble in which the Sun is presently traveling. What this study has done is narrow the location and the time of at least two of these supernovae, a significant discovery, though not the one much of the ignorant press is pushing.

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India signs deal for its own LIGO

11:56 am

India today signed an agreement with the National Science Foundation to build its own LIGO gravitational wave detector

This deal, combined with the possibility that TMT might move to India as well, suggests that India is about to move aggressively from the Third World to the First. And the reason, after decades of wallowing in poverty and failure, is that they finally abandoned in the late 1990s the Soviet models of socialism and communism and embraced private enterprise and capitalism, ideas championed by the United States.

If only some modern Americans would do the same.

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Earth forming around sun-like star?

9:51 am

proto-planetary disk

Worlds without end: The ground-based telescope ALMA has imaged a proto-planetary disk around a sun-like star that suggests an exoEarth is forming there the same distance from the star as our Earth is from our Sun.

The star, TW Hydrae, is a popular target of study for astronomers because of its proximity to Earth (approximately 175 light-years away) and its status as a veritable newborn (about 10 million years old). It also has a face-on orientation as seen from Earth. This affords astronomers a rare, undistorted view of the complete disk. “Previous studies with optical and radio telescopes confirm that this star hosts a prominent disk with features that strongly suggest planets are beginning to coalesce,” said Sean Andrews with the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., and lead author on a paper published today in Astrophysical Journal Letters. “The new ALMA images show the disk in unprecedented detail, revealing a series of concentric dusty bright rings and dark gaps, including intriguing features that suggest a planet with an Earth-like orbit is forming there.”

Other pronounced gap features are located 3 billion and 6 billion kilometers from the central star, similar to the distances from the Sun to Uranus and Pluto in our own Solar System.

The image above right is the inner section of that disk, showing the gap at one astronomical unit, or about 100 million miles from the star, the same as the distance of the Earth from the Sun. Essentially, this relatively close star system is providing us a perfect opportunity to study the formation of a solar system not unlike our own.

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A possible impact on Jupiter?

5:26 pm

On March 17 two different amateur astronomers have taken videos of a bright flash on Jupiter which suggests something had crashed into the gas giant.

March 17th’s impact, if the evidence for it holds up, becomes the fourth such event in the past decade. The largest of these occurred July 19, 2009, and it left a distinctly dark “powder burn” in Jupiter’s upper atmosphere first spotted by Australian astro-imager Anthony Wesley. That was followed by three lesser strikes on June 3, 2010 (recorded independently by Wesley and Christopher Go); on August 10, 2010 (independently seen by Masayuki Tachikawa and Kazuo Aoki); and on September 10, 2012 (seen visually by Dan Petersen and independently recorded by George Hall).

Counting the historic multiple-hit crash of Comet Shoemaker-Levy 9 in July 1994, that’s a grand total of six impacts on Jupiter in the past 22 years.

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Combined Earth-Space radio array discovers superhot quasar interior

11:01 am

The uncertainty of science: Data obtained by combining four ground-based radio telescopes with the Russian orbiting RadioAstron 10-meter radio telescope have detected temperatures of 10 trillion degrees in the quasar 3C 273, a hundred times hotter than predicted possible by theory.

Supermassive black holes, containing millions to billions times the mass of our Sun, reside at the centers of all massive galaxies. These black holes can drive powerful jets that emit prodigiously, often outshining all the stars in their host galaxies. But there is a limit to how bright these jets can be – when electrons get hotter than about 100 billion degrees, they interact with their own emission to produce X-rays and Gamma-rays and quickly cool down.

Astronomers have just reported a startling violation of this long-standing theoretical limit in the quasar 3C 273. “We measure the effective temperature of the quasar core to be hotter than 10 trillion degrees!” comments Yuri Kovalev (Astro Space Center, Lebedev Physical Institute, Moscow, Russia), the RadioAstron project scientist. “This result is very challenging to explain with our current understanding of how relativistic jets of quasars radiate.”

In addition, the higher resolution of the radio images produced by this space/ground-based array was good enough to see the effect produced by the structure of the interstellar material between here and the quasar.

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Video suggests Hitomi tumbling in orbit

9:17 am

Video taken by an amateur astronomer of Hitomi shows it spinning out of control, another indication that something catastrophic occurred to the newly launched X-ray telescope.

The video shows an object that looks like Hitomi, which lost contact Saturday with the Japan Aerospace Exploration Agency (JAXA), shining and then turning extremely dark in short intervals. The wild changes in brightness might mean its sunlight-reflecting side is moving turbulently. “The fact that it is rotating with extreme variations in brightness indicates that it is not controlled and that some event caused it to begin its rotation,” Paul Maley, a former NASA flight controller who observed Hitomi from the ground in Arizona, was quoted as saying.

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Debris spotted near Hitomi

8:31 am

U.S. military observations have detected debris near the Japanese X-ray telescope Hitomi that has failed to respond to communication signals.

The U.S. Joint Space Operations Center on Sunday said it has spotted five objects floating near Japan’s brand new Hitomi X-ray astronomy satellite that lost communication with Earth the previous day. In a Twitter post, the center, which tracks objects in orbit, said it identified five pieces of “break up” debris in the vicinity of the satellite.

None of this sounds encouraging.

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TMT consortium considers India for telescope

6:10 pm

India is now a second candidate location to replace Hawaii for the Thirty Meter Telescope.

Hanle in Ladakh has been short-listed as a prospective site by the TMT board following major hurdles in Mauna Kea, Hawaii – the first choice for the project. An international team is expected to visit Ladakh in a couple of months. … India is already building edge sensors, actuators and system support support assemblies, besides contributing to the software of TMT. India is expected to invest $212 million in the project.

Not only is India contributing technology and money to the telescope, institutes in the country are also participating in the consortium.

Two major scientific institutions – the Indian Institute of Astrophysics (IIA) Bengaluru and the Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune – along with two government departments having working on the project since 2013. The department of science and technology (DST) and the Department of Atomic Energy (DAE) are the government partners, while IIA is the nodal agency.

I think the odds continue to increase that TMT will abandon Hawaii, especially since the state government there continues to drag its feet.

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New Horizons’ future research goals

9:15 am

On Monday at a planetary science conference Alan Stern, the project scientist for New Horizons, outlined the science goals in studying the Kuiper Belt should the spacecraft’s mission be extened through 2021.

The main goal will be the January 1, 2019 fly-by of Kuiper Belt object 2014 MU69, estimated to be between 12 to 24 miles across. However, the proposal also includes the following:

“In addition to making a close flyby of MU69, we’re also going to be close enough in range to study quite a number of other small KBOs, and some large ones that are on the Pluto scale,” Stern said. New Horizons will be able to study them in ways that could never be accomplished from Earth. The closeness of the spacecraft will enable high resolution observations, and the ability to look for satellites that cannot be seen from Earth observatories or with the Hubble Telescope.

“Because we are looking back on the rest of the solar system, at the Kuiper Belt and the Centaur Population,” Stern said, “we’re going to be able to study another 18 or 20 small bodies to determine whether or not the recently discovered rings around the centaur Chariklo are a common occurrence, or something anomalous. And I don’t know of any other way over the next several years, except through New Horizons, that we can develop a data set like that.”

What I find amazing is that it appears from Stern’s remarks that NASA has not yet approved this proposal. Before the team discovered 2014 MU69, I would have been more skeptical about extending the mission, but since they will be able to do a close fly-by of a type of object never before seen, and considering the time and cost it takes to get to the Kuiper Belt, it seems foolish now to not approve this mission extension.

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TMT leadership looks at alternatives to Hawaii

9:01 am

Though they have refused to comment publicly, the Facebook page for the Thirty Meter Telescope on Monday showed the telescope’s management visiting the Canary Islands, a potential alternative site to Hawaii.

Their Facebook post serves two purposes. It shows that they mean business when they say they must start considering abandoning Hawaii. It also might force the Hawaiian state government to stop dragging its feet in the permitting process that protesters have forced TMT to go through, a second time.

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Hubble finds galaxy with record-breaking redshift

4:01 pm

The uncertainty of science: Using the Hubble Space Telescope astronomers have discovered a galaxy with the largest redshift ever measured, 11.1, making it the most distant object so far measured and only about 400 million years after the Big Bang..

The uncertainty is that all theories have said that this galaxy was not supposed to exist at that time.

However, the discovery also raises many new questions as the existence of such a bright and large galaxy is not predicted by theory. “It’s amazing that a galaxy so massive existed only 200 million to 300 million years after the very first stars started to form. It takes really fast growth, producing stars at a huge rate, to have formed a galaxy that is a billion solar masses so soon,” explains Garth Illingworth of the University of California, Santa Cruz.

Marijn Franx, a member of the team from the University of Leiden highlights: “The discovery of GN-z11 was a great surprise to us, as our earlier work had suggested that such bright galaxies should not exist so early in the Universe.” His colleague Ivo Labbe adds: “The discovery of GN-z11 showed us that our knowledge about the early Universe is still very restricted. How GN-z11 was created remains somewhat of a mystery for now.”

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Honing the search for alien civilizations

9:30 am

Worlds without end: In order to increase the odds of contacting extraterrestrial civilizations, astronomers have calculated the area in the sky where an alien-built Kepler could have seen the Earth transit the sun, thus increasing the chances that those alien-astronomers have discovered Earth and have tried to contact us.

“The key point of this strategy is that it confines the search area to a very small part of the sky. As a consequence, it might take us less than a human life span to find out whether or not there are extraterrestrial astronomers who have found the Earth. They may have detected Earth’s biogenic atmosphere and started to contact whoever is home,” explains René Heller from the MPS.

Not every star is equally well suited as a home of extraterrestrial life. The more massive a star, the shorter is its life span. Yet, a long stellar life is considered a prerequisite for the development of higher life forms. Therefore the researchers compiled a list of stars that are not only in the advantageous part of the sky but also offer good chances of hosting evolved forms of life, that is, intelligent life. The researchers compiled a list of 82 nearby Sun-like stars that satisfy their criteria. This catalogue can now serve as an immediate target list for SETI initiatives.

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LISA Pathfinder cubes in freefall

8:38 pm

After a week of testing scientists have now completely released LISA Pathfinder’s two gold-platinum cubes so that they are floating free within the spacecraft.

With the cubes released, the spacecraft is now measuring the position of each cube and using thrusters to adjust its position and keep the cubes floating within it. This success has essentially proven that the technology works, though they now have to see if the technology can be maintained in orbit for a long enough period of time to be worthwhile. If so, this mission will be followed by multiple similar spacecraft, flying in formation while also measuring their positions precisely relative to each other. If a gravitational wave rolls past, they will detect it by the tiny differences of each cube’s position, kind of like beach balls floating on the ocean as a wave rolls past.

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India okays its own LIGO detector

4:32 pm

The Indian government today approved construction of LIGO-India, using some duplicate components already available from the American LIGO gravitational wave detector.

“We have built an exact copy of that instrument that can be used in the LIGO-India Observatory,” says David Shoemaker, leader of the Advanced LIGO Project and director of the MIT LIGO Lab, “ensuring that the new detector can both quickly come up to speed and match the U.S. detector performance.” LIGO will provide Indian researchers with the components and training to build and run the new Advanced LIGO detector, which will then be operated by the Indian team.

What this new instrument will accomplish is to give astronomers more information when a gravitational wave rolls past the Earth. By having detectors half a world apart, they will be able to better triangulate the direction the wave came from, which in turn will help astronomers eventually pinpoint its source event.

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Hubble measures the rotation of an exoplanet

3:03 pm

Worlds without end: Using the Hubble Space Telescope astronomers have measured the daily rotation of a super Jupiter exoplanet 170 light years away.

They estimate, based upon brightness variations attributed to clouds in the upper atmosphere, that the rotation rate is about 10 hours long. We should all recognize however the significant uncertainty of this number. Clouds change, as do weather conditions. The data only gives us a hint at what is going on here.

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Astronomers make first analysis of a SuperEarth’s atmosphere.

9:32 am

Worlds without end: Using the Hubble Space Telescopes astronomers have made the first chemical analysis of a SuperEarth’s atmosphere.

The planet, 55 Cancri e, is estimated to have a mass of eight Earths. Its atmosphere was found to have hydrogen, helium, and the molecule hydrogen cyanide. No water was detected.

Astronomers have used Hubble to detect the components of a number of exoplanets, but these have all been giant planets more like Jupiter. This is the first measurement of an exoplanet whose mass is small enough that it might be rocky, like Earth.

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TMT might abandon Hawaii

9:10 pm

The consortium building the Thirty Meter Telescope (TMT) decided last week that, because of the delays forced on them by protesters in Hawaii, they are going to start identifying alternative locations.

I don’t think they have a choice. They want to start construction no later than 2018, which already involves a three year delay from their original schedule and significant additional costs. I doubt there is any chance that the permit process, which took years the first time they did it, can take anywhere close to that.

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TMT to repeat hearings before state

9:27 pm

After years of doing everything the state of Hawaii demanded in order to get permission to build the Thirty Meter Telescope, a state judge today ordered that the whole process should start over again.

Since this order was instigated by the protesters, and that it appears the government favors those protesters, I expect that there is no chance TMT will ever get approval to build in Hawaii. Though the university consortium building the telescope says they want to go through the new process to get permission, they are wasting their time. It will never happen. The peasants with the pitchforks and burning torches, terrified of new knowledge while preferring the worship of a mountain, are in control in Hawaii.

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