Over the past quarter century, the Hubble Space Telescope has made more than a million observations. Launched in 1990, the telescope completes 15 orbits a day, 340 miles above Earth. It has changed our fundamental understanding of the universe, and NASA hopes the Hubble will last into the next decade. The successor to the Hubble is the long-awaited James Webb Space Telescope (JWST) that now will launch at least a year later than expected, possibly in May 2020, due to delays and cost overruns. Recently, engineers noted small tears in the telescope's five-layered, tennis-court-sized sun shield, and valves in the spacecraft's propulsion system damaged by a cleaning solvent. The construction of the JWST was bound to be a challenge, as it will have a mirror six times larger than the Hubble and operate at 100 times the sensitivity, and has a total mass of about 13,668 pounds. The builder — Northrop Grumman — had 496 full-time workers on the telescope project — 387 more than planned because of technical challenges and work taking longer than expected. The launch delay will require up to 1,000 employees at a cost as high as $200 million, breaking NASA's $8 billion cost ceiling and forcing NASA to go back to Congress for a new budget authorization. NASA has convened a review board to monitor the JWST construction. Back on Earth, a recent court decision on whether to place a $1.4 billion telescope in Hawaii to further astronomy research has been delayed yet again. The Thirty Meter Telescope (TMT) International Observatory still wants to build the telescope on its preferred site of Mauna Kea, a mountain in Hawaii, but the site has been publicly debated since 2009 as the land is considered sacred by some Native Hawaiians. Two appeals remain before the Hawaii Supreme Court, one challenging the sublease and land use permits issued, and the other stating that proposed use of the land interferes with the right to exercise indigenous cultural practices. An alternative location on the island of La Palma in Spain’s Canary Islands remains under consideration.
Gravity as a Lens
NASA’s Hubble Space Telescope recently was able to pinpoint a star more than halfway across the universe, setting a new distance record. Icarus, a blue supergiant star 9 billion light-years distant is the farthest individual star ever seen. Normally too faint to view, Icarus became visible due to a phenomenon called “gravitational lensing.” Gravity from a closer massive cluster of galaxies acts as a lens in space, amplifying the light from the star, making extremely faint and distant objects bright enough to see. This new way for astronomers to study individual stars in distant galaxies provides a rare, detailed look at how stars evolve. Indeed, Icarus is 100 times farther away than the next individual star that astronomers can study, except for supernovas. In the case of Icarus, the galaxy cluster “MACS J1149+2223” — about 5 billion light-years from Earth — acted as the “magnifying glass" that, coupled with Hubble’s tremendous resolution and sensitivity, allowed astronomers to study Icarus. Astronomers had been using the Hubble to monitor a supernova and spotted a new point of light. Analyzing the light coming from this object, they discovered it was a blue star, possibly hundreds of thousands of times brighter than our sun. At this distance, it would have been much too far away — even for the Hubble — to see without the use of gravitational lensing.
Not Enough Phosphorus?
Scientists have determined what elements are essential for the formation of life, at least under conditions we experience on Earth. One of those elements is phosphorus. Recent findings suggest that it may have been a simple matter of luck that our planet had just enough of the element for life to begin. New observations of the Crab Nebula — first seen in 1054 as a supernova — show that the abundance and distribution of phosphorus in the Milky Way galaxy may be more random than thought. Most of the phosphorus in the universe was created as a result of the death of massive stars or when a massive star exhausted its fuel and exploded, becoming a supernova. While phosphorus normally is difficult to observe, observations of the remains of a supernova Cassiopeia A. in 2013 found up to 100 times more phosphorus than astronomers have observed in the rest of the Milky Way. If the abundance of phosphorus varies significantly across the galaxy, so might also be the possibility of life on other planets. These recent observations only were able to measure parts of the Crab Nebula, and researchers hope eventually to use the European Space Agency's Herschel Space Observatory Telescope to study the rest of the nebula and measure phosphorus in other supernova remnants across the universe.
The Sky for May
Jupiter shines his brightest in May, rising in the southeast evening sky at 8:54 pm on the first. Saturn follows, rising about 45 minutes into the morning of the second, with Mars rising an hour later. Mercury can then be seen rising at 5:30 a.m., almost directly in the east. Venus is conspicuous in the west after sunset, moving from Taurus into Gemini over the month. On the morning of the fifth, Saturn and the waning gibbous moon are less than 2 degrees apart. The Eta Aquariid meteor shower occurs before dawn on May 7. While the shower occasionally peaks at about one a meteor a minute, the radiant of the shower is only above the horizon for the few hours before dawn — and the light from the waning gibbous moon will interfere with this year’s view.
At the Planetarium
The Hoover-Price Planetarium continues to present the periodically updated “The Universe at Large” at 1 p.m. on Saturdays and 2 p.m. on Sundays. The planetarium seats 65 and is located inside the Wm. McKinley Presidential Library & Museum at 800 McKinley Monument Drive NW in Canton. Admission is included with admission to the museum. Children must be 5 years or older to attend, and the First Monday of the month program at 1 p.m. is for adults. For more information, visit the planetarium’s blog on the museum’s website, or call the museum at 330-455-7043.
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