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Deborah Byrd

Where’s the moon? Waxing crescent

The young moon is back in the evening sky, waxing toward a lunar eclipse on January 31.

NASA and NOAA: 2017 was record-setting for warmth

NASA says 2nd-warmest year on record. NOAA says 3rd-warmest. Their methodologies differ slightly, but – by both standards – the 2017 results make the past 4 years the hottest yet recorded.

Saturn moon Titan has a sea level

A new topographic map of Titan, plus a new study showing that Titan’s seas lie at an average elevation – a sea level – just as Earth’s do.

How massive can neutron stars be?

Settling a long debate, astrophysicists at Goethe University Frankfurt now say neutron stars can’t exceed the mass of 2.16 suns.

Supercomputer insights on mysterious black hole jets

Scientists used the Blue Waters supercomputer to show that a black hole’s relativistic jets and accretion disk both may be spinning – and precessing over time – around an axis separate from the black hole itself.

Zooming star points to black hole in globular star cluster

Globular star clusters contain our galaxy’s most ancient stars. Astronomers didn’t expect to find a 4-solar-mass black hole in one, but … voila!

No double moon in 2018, or ever

2018 will be an excellent year to view Mars. The planet will be closer to Earth – and brighter in our sky – than since 2003. But as big as the moon? Heck no.

New moon is January 16-17

This new moon is most nearly between the Earth and sun for this month. It crosses the sky with the sun during the day.

Best photos: Morning planets!

On Sunday morning, Jupiter and Mars were half a moon-diameter apart. Now the moon is sweeping past. Plus Mercury and Saturn are in conjunction this weekend. Photos here.

Achernar marks the end of the River

The bright, southerly star Achernar marks the end of the River in the constellation Eridanus. Many at northerly latitudes make a game of trying to catch a glimpse of it.