Wed. Nov. 8 - Observatory closed due to cloud cover. We'll try again next week.
Each fall and spring season, we host a set of public observatory nights on Wednesday evenings. This spring, we're set to start on March 19, weather allowing. Schedule coming soon!
The 2023 Annular Eclipse as seen from Albuquerque, NM // Jordan Martin
Video of the Day!
Hubble has discovered that Jupiter’s red spot - a storm larger than Earth - is wobbling!
We were extremely fortunate to have Jocelyn Bell Burnell as a virtual guest in a women in science class! She was a pleasure to listen to and continues to be an inspiration.
On August 6, 1967, astrophysicist Jocelyn Bell Burnell noticed a blip in her radio telescope data. And then another. Eventually, Bell Burnell figured out that these blips, or pulses, were not from people or machines.
The blips were constant. There was something in space that was pulsing in a regular pattern, and Bell Burnell figured out that it was a pulsar: a rapidly spinning neutron star emitting beams of light. Neutron stars are superdense objects created when a massive star dies. Not only are they dense, but neutron stars can also spin really fast! Every star we observe spins, and due to a property called angular momentum, as a collapsing star gets smaller and denser, it spins faster. It’s like how ice skaters spin faster as they bring their arms closer to their bodies and make the space that they take up smaller.
The pulses of light coming from these whirling stars are like the beacons spinning at the tops of lighthouses that help sailors safely approach the shore. As the pulsar spins, beams of radio waves (and other types of light) are swept out into the universe with each turn. The light appears and disappears from our view each time the star rotates.
After decades of studying pulsars, astronomers wondered—could they serve as cosmic beacons to help future space explorers navigate the universe? To see if it could work, scientists needed to do some testing!
First, it was important to gather more data. NASA’s NICER, or Neutron star Interior Composition Explorer, is a telescope that was installed aboard the International Space Station in 2017. Its goal is to find out things about neutron stars like their sizes and densities, using an array of 56 special X-ray concentrators and sensitive detectors to capture and measure pulsars’ light.
But how can we use these X-ray pulses as navigational tools? Enter SEXTANT, or Station Explorer for X-ray Timing and Navigation Technology. If NICER was your phone, SEXTANT would be like an app on it.
During the first few years of NICER’s observations, SEXTANT created an on-board navigation system using NICER’s pulsar data. It worked by measuring the consistent timing between each pulsar’s pulses to map a set of cosmic beacons.
When calculating position or location, extremely accurate timekeeping is essential. We usually rely on atomic clocks, which use the predictable fluctuations of atoms to tick away the seconds. These atomic clocks can be located on the ground or in space, like the ones on GPS satellites. However, our GPS system only works on or close to Earth, and onboard atomic clocks can be expensive and heavy. Using pulsar observations instead could give us free and reliable “clocks” for navigation. During its experiment, SEXTANT was able to successfully determine the space station’s orbital position!
We can calculate distances using the time taken for a signal to travel between two objects to determine a spacecraft’s approximate location relative to those objects. However, we would need to observe more pulsars to pinpoint a more exact location of a spacecraft. As SEXTANT gathered signals from multiple pulsars, it could more accurately derive its position in space.
So, imagine you are an astronaut on a lengthy journey to the outer solar system. You could use the technology developed by SEXTANT to help plot your course. Since pulsars are reliable and consistent in their spins, you wouldn’t need Wi-Fi or cell service to figure out where you were in relation to your destination. The pulsar-based navigation data could even help you figure out your ETA!
None of these missions or experiments would be possible without Jocelyn Bell Burnell’s keen eye for an odd spot in her radio data decades ago, which set the stage for the idea to use spinning neutron stars as a celestial GPS. Her contribution to the field of astrophysics laid the groundwork for research benefitting the people of the future, who yearn to sail amongst the stars.
Keep up with the latest NICER news by following NASA Universe on X and Facebook and check out the mission’s website. For more on space navigation, follow @NASASCaN on X or visit NASA’s Space Communications and Navigation website.
Make sure to follow us on Tumblr for your regular dose of space!
The Orion You Can Almost See Image Credit & Copyright: Michele Guzzini
Explanation: Do you recognize this constellation? Although it is one of the most recognizable star groupings on the sky, this is a more full Orion than you can see – an Orion only revealed with long exposure digital camera imaging and post- processing. Here the cool red giant Betelgeuse takes on a strong orange tint as the brightest star on the upper left. Orion’s hot blue stars are numerous, with supergiant Rigel balancing Betelgeuse on the lower right, and Bellatrix at the upper right. Lined up in Orion’s belt are three stars all about 1,500 light-years away, born from the constellation’s well-studied interstellar clouds. Just below Orion’s belt is a bright but fuzzy patch that might also look familiar – the stellar nursery known as Orion’s Nebula. Finally, just barely visible to the unaided eye but quite striking here is Barnard’s Loop – a huge gaseous emission nebula surrounding Orion’s Belt and Nebula discovered over 100 years ago by the pioneering Orion photographer E. E. Barnard.
∞ Source: apod.nasa.gov/apod/ap240116.html
The Black Eye Galaxy. Image Credit: Shane Johnson | Jamie Kern | BSU Observatory.
Imaged in luminance and photometric R, V and B filters. Total exposure time ~25 minutes.
The Black Eye Galaxy (M64) is a relatively nearby spiral with an extraordinary amount of dark dust partially obscuring its nucleus. Red hues peeking out in these dust lanes are caused by reddening when the dust scatters the bluer light from stars embedded within it. The color difference between the center and spiral arms is due to an average age difference between the stars in these locations--blue stars have short lives, so as the star population ages the overall color appears more red.
IC 2118: The Witch Head Nebula Image Credit & Copyright: Abdullah Alharbi
Explanation: Does this nebula look like the head of a witch? The nebula is known popularly as the Witch Head Nebula because, it is said, the nebula’s shape resembles a Halloween-style caricature of a witch’s head. Exactly how, though, can be a topic of imaginative speculation. What is clear is that IC 2118 is about 50 light-years across and made of gas and dust that points to – because it has been partly eroded by – the nearby star Rigel. One of the brighter stars in the constellation Orion, Rigel lies below the bottom of the featured image. The blue color of the Witch Head Nebula and is caused not only by Rigel’s intense blue starlight but because the dust grains scatter blue light more efficiently than red. The same physical process causes Earth’s daytime sky to appear blue, although the scatterers in planet Earth’s atmosphere are molecules of nitrogen and oxygen.
∞ Source: apod.nasa.gov/apod/ap231004.html
Wed. Oct. 22: We'll be open tonight from 7 - 8 pm. We expect some clouds, but we should still be able to catch some nice glimpses of the sky. Saturn is still the star of the show!
STEM Education, Astrophysics Research, Astrophotography, and Outreach located at 24 Park Ave., Bridgewater MA. You'll find us on the two outdoor balconies on the 5th floor, and you'll find our official website here: https://www.bridgew.edu/center/case/observatory .
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