As the Spitzer Space Telescope’s 16-year mission ends, we’re celebrating the legacy of our infrared explorer. It was one of four Great Observatories – powerful telescopes also including Hubble, Chandra and Compton – designed to observe the cosmos in different parts of the electromagnetic spectrum.
Light our eyes can see
The part of the spectrum we can see is called, predictably, visible light. But that’s just a small segment of all the wavelengths of the spectrum. The Hubble Space Telescope observes primarily in the visible spectrum. Our Chandra X-ray Observatory is designed to detect (you guessed it) X-ray emissions from very hot regions of the universe, like exploded stars and matter around black holes. Our Compton Gamma Ray Observatory, retired in 2000, produced the first all-sky survey in gamma rays, the most energetic and penetrating form of light.
Then there’s infrared…
Infrared radiation, or infrared light, is another type of energy that we can’t see but can feel as heat. All objects in the universe emit some level of infrared radiation, whether they’re hot or cold. Spitzer used its infrared instrument to make discoveries in our solar system (including Saturn’s largest ring) all the way to the edge of the universe. From stars being born to planets beyond our solar system (like the seven Earth-size exoplanets around the star TRAPPIST-1), Spitzer’s science discoveries will continue to inspire the world for years to come.
Multiple wavelengths
Together, the work of the Great Observatories gave us a more complete view and understanding of our universe.
Hubble and Chandra will continue exploring our universe, and next year they’ll be joined by an even more powerful observatory … the James Webb Space Telescope!
Many of Spitzer’s breakthroughs will be studied more precisely with the Webb Space Telescope. Like Spitzer, Webb is specialized for infrared light. But with its giant gold-coated beryllium mirror and nine new technologies, Webb is about 1,000 times more powerful. The forthcoming telescope will be able to push Spitzer’s science findings to new frontiers, from identifying chemicals in exoplanet atmospheres to locating some of the first galaxies to form after the Big Bang.
We can’t wait for another explorer to join our space telescope superteam!
Why are these meteor trails nearly parallel? Because they were all shed by the same space rock and so can be traced back to the same direction on the sky: the radiant of the Quadrantid Meteor Shower. This direction used to be toward the old constellation of Quadrans Muralis, hence the name Quadrantids, but when the International Astronomical Union formulated its list of modern constellations in 1922, this constellation did not make the list. Even though the meteors are now considered to originate from the recognized constellation of Bootes, the old name stuck. Regardless of the designation, every January the Earth moves through a dust stream and bits of this dust glow as meteors as they heat up in Earth’s atmosphere. The featured image composite was taken on January 4 with a picturesque snowy Slovakian landscape in the foreground, and a deep-exposure sky prominently featuring the constellation Orion in the background. The red star Betelgeuse appears unusually dim – its fading over the past few months is being tracked by astronomers.
President Trump used his first prime-time address from the Oval Office to make the case for his controversial border wall. The president’s demand for $5.7 billion in wall funding — and Democrats’ opposition — has led to a partial shutdown of the federal government.
Here we check some of the arguments made by the president and top Democrats in their response.
Trump’s Speech
Claim 1: Humanitarian and security crisis
“There is a growing humanitarian and security crisis at our Southern border.”
Fact check: Illegal border crossings in the most recent fiscal year (ending in September 2018) were actually lower than either 2016 or 2014 and much lower than at their peak around 2000. The number of unauthorized border-crossers is also dwarfed by the number of people who overstay their visas. But there has been a spike in crossings in the past few months, topping 60,000 in both October and November. And while illegal crossings are still well below the levels of a generation ago, the makeup of the traffic has changed. There are now many more children and families from Central America, who present different challenges than single adults from Mexico.
Many of the Central American migrants are seeking asylum, citing a fear of violence or persecution back home. While the majority of these asylum claims are ultimately rejected, assessing them can take months or years. In the past, asylum-seekers were typically released into the U.S. during this period, a practice the Trump administration criticizes as “catch and release.” The administration wants to detain migrants while their asylum claims are adjudicated. This has led to overcrowded detention centers. And under a court order, young migrants generally cannot be detained for more than about 20 days. (The administration tried to get around that last year with its ill-fated and short-lived family separation policy, to allow indefinite detention of adults while children were turned over to the Health and Human Services Department or resettled with family members.) Importantly, most asylum-seekers turn themselves in to U.S. authorities, which they could do with or without a border wall.
Wednesday was the day astronomers said goodbye to the old Milky Way they had known and loved and hello to a new view of our home galaxy.
A European Space Agency mission called Gaia just released a long-awaited treasure trove of data: precise measurements of 1.7 billion stars.
It’s unprecedented for scientists to know the exact brightness, distances, motions and colors of more than a billion stars. The information will yield the best three-dimensional map of our galaxy ever.
The sun photographed from the same spot, at the same hour throughout different days in a year. This is called an analemma. It is caused by the 23.5 degree tilt of the earth and the elliptical orbit. (Source)(Photographer: Tunc Tezel)
In a much-watched case, a Michigan agency has approved Nestlé’s plan to boost the amount of water it takes from the state. The request attracted a record number of public comments — with 80,945 against and 75 in favor.
Nestlé’s request to the Michigan Department of Environmental Quality to pump 576,000 gallons of water each day from the White Pine Springs well in the Great Lakes Basin was “highly controversial,” member station Michigan Radio reports. But despite deep public opposition, the agency concluded that the company’s plan met with legal standards.
“It is very clear this permit decision is of great interest to not only residents in the surrounding counties, but to Michiganders across the state as well,” MDEQ Director C. Heidi Grether said in approving the permit.
“In full transparency, the majority of the public comments were in opposition of the permit,” Grether added, “but most of them related to issues of public policy which are not, and should not be, part of an administrative permit decision.”
Under the plan, Nestlé will be approved to pump up to 400 gallons of water per minute from the well, rather than the 250 gallons per minute it had been extracting. The company first applied for the new permit in July 2016.
