How can I see Southern Cross now?


A reader asked:

When can I see the Southern Cross in Hawaii?

The answer is now – late December and early January – but you’ll have to look for it at just the right place and time of night. Each year at this time, Hawaiians – or those at the latitude of Hawaii – can see the Southern Cross in the southern sky briefly before dawn. The Southern Cross, aka the constellation Crux, stands close to upright, but quite low in the sky, for the latitude of Honolulu. Be sure to find an unobstructed southern horizon. Follow the links below to learn more about the Southern Cross.

How far south do I have to be to see the Southern Cross?

Are there guide stars to the Southern Cross?

How else can I know if the Southern Cross is visible in my sky?

Globe showing Pacific Ocean with arrow to location of Hawaii.

From the latitude of Hawaii (see arrow), or farther south, you can see the Southern Cross before sunrise in late December and early January. Map via WorldAtlas.com.

How far south do I have to be to see the Southern Cross? Hawaii is at 21 degrees north latitude. Other cities at about this same latitude include Mecca in Saudi Arabia, Leon and Guanajuato in Mexico, and Hanoi in Vietnam.

All of you at this latitude will be able to see the Southern Cross before dawn for at least another month.

Are you south of Hawaii’s latitude? Then you can see the Southern Cross, Rigel Kentaurus and Hadar all the higher in the sky before dawn now. From Australia or New Zealand – or South America or South Africa – Crux is circumpolar. That is, it circles around the sky’s southern pole and appears for most, if not all, of the night.

EarthSky 2020 lunar calendars are available! They make great gifts. Order now. Going fast!

Diagram: Guidestars to the Southern Cross.

Rigel Kentaurus (aka Alpha Centauri), Hadar and the Southern Cross.

Are there guide stars to the Southern Cross? Look at the photo at the top of this post, by Jv Noriega in the Philippines. Also look at the chart above. Notice the two stars, Rigel Kentaurus and Hadar, in the constellation Centaurus. Rigel Kentaurus is also known as Alpha Centauri, the star system nearest to Earth, at a little more than 4 light-years away.

Rigel Kentaurus (Alpha Centauri) and Hadar point to the Southern Cross.

Diagram: Milky Way, constellation Cassiopeia, and Polaris.

If you can see the constellation Cassiopeia in your northern sky, then the Southern Cross is below your horizon. Cassiopeia is shaped like the letter M or W.

How else can I know if the Southern Cross is visible in my sky? If you know a bit about the sky, then there is one surefire way to know if the Southern Cross is visible in your sky. When the easy-to-find constellation Cassiopeia the Queen is visible in your sky, the Southern Cross is below your horizon. So, for example, Cassiopeia lights up Hawaiian skies on winter evenings, but it sets beneath Hawaii’s northern horizon several hours before sunrise. As Cassiopeia sets, the Southern Cross rises.

Meanwhile, for latitudes north of Hawaii (for example, most of the continental U.S. – except for southern Florida and Texas), Cassiopeia is circumpolar. It circles endlessly around the sky’s north pole and never sets. Therefore, the Southern Cross never rises as seen from northerly latitudes.

The Southern Cross marks the southern terminus of the glowing band of stars that we call the Milky Way – really the edgewise view into our own Milky Way galaxy. Meanwhile, Cassiopeia lodges at the Milky Way’s northern terminus in our sky.

Night sky above dark trees, with lines between stars showing cross-shaped constellation.

Matthew Chin in Hong Kong caught Crux – aka the Southern Cross – on December 21, 2017.

Bottom line: Late December and early January are a good time for those at northerly latitudes – latitude of Hawaii or comparable latitudes – to look before dawn for the Southern Cross. It is visible briefly before dawn. Hawaii is at 21 degrees north latitude. Other cities at about this same latitude include Mecca in Saudi Arabia, Leon and Guanajuato in Mexico, and Hanoi in Vietnam.

Southern Cross: Signpost of southern skies

Alpha Centauri: Closest star system to our sun

Purchase a planisphere – or guide to the stars – an essential tool for beginning stargazers.



from EarthSky https://ift.tt/2ZiP8Sd

A reader asked:

When can I see the Southern Cross in Hawaii?

The answer is now – late December and early January – but you’ll have to look for it at just the right place and time of night. Each year at this time, Hawaiians – or those at the latitude of Hawaii – can see the Southern Cross in the southern sky briefly before dawn. The Southern Cross, aka the constellation Crux, stands close to upright, but quite low in the sky, for the latitude of Honolulu. Be sure to find an unobstructed southern horizon. Follow the links below to learn more about the Southern Cross.

How far south do I have to be to see the Southern Cross?

Are there guide stars to the Southern Cross?

How else can I know if the Southern Cross is visible in my sky?

Globe showing Pacific Ocean with arrow to location of Hawaii.

From the latitude of Hawaii (see arrow), or farther south, you can see the Southern Cross before sunrise in late December and early January. Map via WorldAtlas.com.

How far south do I have to be to see the Southern Cross? Hawaii is at 21 degrees north latitude. Other cities at about this same latitude include Mecca in Saudi Arabia, Leon and Guanajuato in Mexico, and Hanoi in Vietnam.

All of you at this latitude will be able to see the Southern Cross before dawn for at least another month.

Are you south of Hawaii’s latitude? Then you can see the Southern Cross, Rigel Kentaurus and Hadar all the higher in the sky before dawn now. From Australia or New Zealand – or South America or South Africa – Crux is circumpolar. That is, it circles around the sky’s southern pole and appears for most, if not all, of the night.

EarthSky 2020 lunar calendars are available! They make great gifts. Order now. Going fast!

Diagram: Guidestars to the Southern Cross.

Rigel Kentaurus (aka Alpha Centauri), Hadar and the Southern Cross.

Are there guide stars to the Southern Cross? Look at the photo at the top of this post, by Jv Noriega in the Philippines. Also look at the chart above. Notice the two stars, Rigel Kentaurus and Hadar, in the constellation Centaurus. Rigel Kentaurus is also known as Alpha Centauri, the star system nearest to Earth, at a little more than 4 light-years away.

Rigel Kentaurus (Alpha Centauri) and Hadar point to the Southern Cross.

Diagram: Milky Way, constellation Cassiopeia, and Polaris.

If you can see the constellation Cassiopeia in your northern sky, then the Southern Cross is below your horizon. Cassiopeia is shaped like the letter M or W.

How else can I know if the Southern Cross is visible in my sky? If you know a bit about the sky, then there is one surefire way to know if the Southern Cross is visible in your sky. When the easy-to-find constellation Cassiopeia the Queen is visible in your sky, the Southern Cross is below your horizon. So, for example, Cassiopeia lights up Hawaiian skies on winter evenings, but it sets beneath Hawaii’s northern horizon several hours before sunrise. As Cassiopeia sets, the Southern Cross rises.

Meanwhile, for latitudes north of Hawaii (for example, most of the continental U.S. – except for southern Florida and Texas), Cassiopeia is circumpolar. It circles endlessly around the sky’s north pole and never sets. Therefore, the Southern Cross never rises as seen from northerly latitudes.

The Southern Cross marks the southern terminus of the glowing band of stars that we call the Milky Way – really the edgewise view into our own Milky Way galaxy. Meanwhile, Cassiopeia lodges at the Milky Way’s northern terminus in our sky.

Night sky above dark trees, with lines between stars showing cross-shaped constellation.

Matthew Chin in Hong Kong caught Crux – aka the Southern Cross – on December 21, 2017.

Bottom line: Late December and early January are a good time for those at northerly latitudes – latitude of Hawaii or comparable latitudes – to look before dawn for the Southern Cross. It is visible briefly before dawn. Hawaii is at 21 degrees north latitude. Other cities at about this same latitude include Mecca in Saudi Arabia, Leon and Guanajuato in Mexico, and Hanoi in Vietnam.

Southern Cross: Signpost of southern skies

Alpha Centauri: Closest star system to our sun

Purchase a planisphere – or guide to the stars – an essential tool for beginning stargazers.



from EarthSky https://ift.tt/2ZiP8Sd

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