NASA NIGHT SKY NOTES FOR APRIL 2020

This Article is distributed by NASA Night Sky Network.  The Night Sky Network program supports astronomy clubs across the USA dedicated to astronomy outreach.  Visit nightsky.jpl.nasa.org  to find local clubs, event and more!

Hubble at 30: Three Decades of Cosmic Discovery

David Prosper

The Hubble Space Telescope celebrates its 30th birthday in orbit around Earth this month! It’s hard to believe how much this telescope has changed the face of astronomy in just three decades. It had a rough start -- an 8-foot mirror just slightly out of focus in the most famous case of spherical aberration of all time. But subsequent repairs and upgrades by space shuttle astronauts made Hubble a symbol of the ingenuity of human spaceflight and one of the most important scientific instruments ever created. Beginning as a twinkle in the eye of the late Nancy Grace Roman, the Hubble Space Telescope’s work over the past thirty years changed the way we view the universe, and more is yet to come!

We’ve all seen the amazing images created by Hubble and its team of scientists, but have you seen Hubble yourself? You actually can! Hubble’s orbit – around 330 miles overhead -- is close enough to Earth that you can see it at night. The best times are within an hour after sunset or before sunrise, when its solar panels are angled best to reflect the light of the Sun back down to Earth. You can’t see the structure of the telescope, but you can identify it as a bright star-like point, moving silently across the night sky. It’s not as bright as the Space Station, which is much larger and whose orbit is closer to Earth (about 220 miles), but it’s still very noticeable as a single steady dot of light, speeding across the sky. Hubble’s orbit brings it directly overhead for observers located near tropical latitudes; observers further north and south can see it closer to the horizon. You can find sighting opportunities using satellite tracking apps for your smartphone or tablet, and dedicated satellite tracking websites. These resources can also help you identify other satellites that you may see passing overhead during your stargazing sessions.

NASA has a dedicated site for Hubble’s 30th’s anniversary at bit.ly/NASAHubble30. The Night Sky Network’s “Why Do We Put Telescopes in Space?” activity can help you and your audiences discover why we launch telescopes into orbit, high above the interference of Earth’s atmosphere, at bit.ly/TelescopesInSpace. Amateur astronomers may especially enjoy Hubble’s images of the beautiful objects found in both the Caldwell and Messier catalogs, at bit.ly/HubbleCaldwell and bit.ly/HubbleMessier. As we celebrate Hubble’s legacy, we look forward to the future, as there is another telescope ramping up that promises to further revolutionize our understanding of the early universe: the James Webb Space Telescope!

 Discover more about the history and future of Hubble and space telescopes at nasa.gov.

Image Credit: NASA

Hubble’s “first light” image. Even with the not-yet-corrected imperfections in its mirror, its images were generally sharper compared to photos taken by ground-based telescopes at the time. Image Credit: NASA

25 years! 

Its been a long time,did not realize how fast the time went since we started our astronomy club back in 1995.  To all members that stuck with us in good and bad times, I thank all of you, without your help we could have not gotten to this point.

Also remember our John Johnson Memorial Star Party in August 2020, in remembrance the loss of our great friend, JJ.

NASA NIGHT SKY NOTES FOR MARCH 2020

This Article is distributed by NASA Night Sky Network.  The Night Sky Network program supports astronomy clubs across the USA dedicated to astronomy outreach.  Visit nightsky.jpl.nasa.org  to find local clubs, event and more!

Dim Delights in Cancer

David Prosper

Cancer the Crab is a dim constellation, yet it contains one of the most beautiful and easy-to-spot star clusters in our sky: the Beehive Cluster. Cancer also possesses one of the most studied exoplanets: the superhot super-Earth, 55 Cancri e.

Find Cancer’s dim stars by looking in between the brighter neighboring constellations of Gemini and Leo. Don’t get frustrated if you can’t find it at first, since Cancer isn’t easily visible from moderately light polluted areas. Once you find Cancer, look for its most famous deep-sky object: the Beehive Cluster! It’s a large open cluster of young stars, three times larger than our Moon in the sky. The Beehive is visible to unaided eyes under good sky conditions as a faint cloudy patch, but is stunning when viewed through binoculars or a wide-field telescope. It was one of the earliest deep-sky objects noticed by ancient astronomers, and so the Beehive has many other names, including Praesepe, Nubilum, M44, the Ghost, and Jishi qi. Take a look at it on a clear night through binoculars. Do these stars look like a hive of buzzing bees? Or do you see something else? There’s no wrong answer, since this large star cluster has intrigued imaginative observers for thousands of years.

55 Cancri is a nearby binary star system, about 41 light years from us and faintly visible under excellent dark sky conditions. The larger star is orbited by at least five planets including 55 Cancri e, (a.k.a. Janssen, named after one of the first telescope makers). Janssen is a “super-earth,” a large rocky world 8 times the mass of our Earth, and orbits its star every 18 hours, giving it one of the shortest years of all known planets! Janssen was the first exoplanet to have its atmosphere successfully analyzed. Both the Hubble and recently-retired Spitzer space telescopes confirmed that the hot world is enveloped by an atmosphere of helium and hydrogen with traces of hydrogen cyanide: not a likely place to find life, especially since the surface is probably scorching hot rock. The NASA Exoplanet Catalog has more details about this and many other exoplanets at bit.ly/nasa55cancrie.

How do astronomers find planets around other star systems? The Night Sky Network’s “How We Find Planets” activity helps demonstrate both the transit and wobble methods of exoplanet detection: bit.ly/findplanets. Notably, 55 Cancri e was discovered via the wobble method in 2004, and then the transit method confirmed the planet’s orbital period in 2011!

Want to learn more about exoplanets? Get the latest NASA news about worlds beyond our solar system at nasa.gov

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Artist concept of 55 Cancri e orbiting its nearby host star. Find details from the Spitzer Space Telescope’s close study of its atmosphere at: bit.ly/spitzer55cancrie  and the Hubble Space Telescope’s observations at bit.ly/hubble55cancrie Credit: NASA/JPL-Caltech

Look for Cancer in between the “Sickle” or “Question Mark” of Leo and the bright twin stars of Gemini. You can’t see the planets around 55 Cancri, but if skies are dark enough you can see the star itself. Can you see the Beehive Cluster?